From e40fbbf0572c5e41dc87ad79001748ed399ce32d Mon Sep 17 00:00:00 2001 From: Usama Arif Date: Wed, 19 Jan 2022 11:44:40 +0000 Subject: uapi/bpf: Add missing description and returns for helper documentation Both description and returns section will become mandatory for helpers and syscalls in a later commit to generate man pages. This commit also adds in the documentation that BPF_PROG_RUN is an alias for BPF_PROG_TEST_RUN for anyone searching for the syscall in the generated man pages. Signed-off-by: Usama Arif Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220119114442.1452088-1-usama.arif@bytedance.com --- tools/include/uapi/linux/bpf.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'tools/include/uapi') diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index b0383d371b9a..a9c96c21330a 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -330,6 +330,8 @@ union bpf_iter_link_info { * *ctx_out*, *data_in* and *data_out* must be NULL. * *repeat* must be zero. * + * BPF_PROG_RUN is an alias for BPF_PROG_TEST_RUN. + * * Return * Returns zero on success. On error, -1 is returned and *errno* * is set appropriately. @@ -1775,6 +1777,8 @@ union bpf_attr { * 0 on success, or a negative error in case of failure. * * u64 bpf_get_current_pid_tgid(void) + * Description + * Get the current pid and tgid. * Return * A 64-bit integer containing the current tgid and pid, and * created as such: @@ -1782,6 +1786,8 @@ union bpf_attr { * *current_task*\ **->pid**. * * u64 bpf_get_current_uid_gid(void) + * Description + * Get the current uid and gid. * Return * A 64-bit integer containing the current GID and UID, and * created as such: *current_gid* **<< 32 \|** *current_uid*. @@ -2256,6 +2262,8 @@ union bpf_attr { * The 32-bit hash. * * u64 bpf_get_current_task(void) + * Description + * Get the current task. * Return * A pointer to the current task struct. * @@ -2369,6 +2377,8 @@ union bpf_attr { * indicate that the hash is outdated and to trigger a * recalculation the next time the kernel tries to access this * hash or when the **bpf_get_hash_recalc**\ () helper is called. + * Return + * void. * * long bpf_get_numa_node_id(void) * Description @@ -2466,6 +2476,8 @@ union bpf_attr { * A 8-byte long unique number or 0 if *sk* is NULL. * * u32 bpf_get_socket_uid(struct sk_buff *skb) + * Description + * Get the owner UID of the socked associated to *skb*. * Return * The owner UID of the socket associated to *skb*. If the socket * is **NULL**, or if it is not a full socket (i.e. if it is a @@ -3240,6 +3252,9 @@ union bpf_attr { * The id is returned or 0 in case the id could not be retrieved. * * u64 bpf_get_current_cgroup_id(void) + * Description + * Get the current cgroup id based on the cgroup within which + * the current task is running. * Return * A 64-bit integer containing the current cgroup id based * on the cgroup within which the current task is running. -- cgit v1.2.3 From b44123b4a3dcad4664d3a0f72c011ffd4c9c4d93 Mon Sep 17 00:00:00 2001 From: YiFei Zhu Date: Thu, 16 Dec 2021 02:04:27 +0000 Subject: bpf: Add cgroup helpers bpf_{get,set}_retval to get/set syscall return value The helpers continue to use int for retval because all the hooks are int-returning rather than long-returning. The return value of bpf_set_retval is int for future-proofing, in case in the future there may be errors trying to set the retval. After the previous patch, if a program rejects a syscall by returning 0, an -EPERM will be generated no matter if the retval is already set to -err. This patch change it being forced only if retval is not -err. This is because we want to support, for example, invoking bpf_set_retval(-EINVAL) and return 0, and have the syscall return value be -EINVAL not -EPERM. For BPF_PROG_CGROUP_INET_EGRESS_RUN_ARRAY, the prior behavior is that, if the return value is NET_XMIT_DROP, the packet is silently dropped. We preserve this behavior for backward compatibility reasons, so even if an errno is set, the errno does not return to caller. However, setting a non-err to retval cannot propagate so this is not allowed and we return a -EFAULT in that case. Signed-off-by: YiFei Zhu Reviewed-by: Stanislav Fomichev Link: https://lore.kernel.org/r/b4013fd5d16bed0b01977c1fafdeae12e1de61fb.1639619851.git.zhuyifei@google.com Signed-off-by: Alexei Starovoitov --- include/linux/bpf.h | 10 ++++++---- include/uapi/linux/bpf.h | 18 ++++++++++++++++++ kernel/bpf/cgroup.c | 38 +++++++++++++++++++++++++++++++++++++- tools/include/uapi/linux/bpf.h | 18 ++++++++++++++++++ 4 files changed, 79 insertions(+), 5 deletions(-) (limited to 'tools/include/uapi') diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 7b0c11f414d0..dce54eb0aae8 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -1299,7 +1299,7 @@ BPF_PROG_RUN_ARRAY_CG_FLAGS(const struct bpf_prog_array __rcu *array_rcu, while ((prog = READ_ONCE(item->prog))) { run_ctx.prog_item = item; func_ret = run_prog(prog, ctx); - if (!(func_ret & 1)) + if (!(func_ret & 1) && !IS_ERR_VALUE((long)run_ctx.retval)) run_ctx.retval = -EPERM; *(ret_flags) |= (func_ret >> 1); item++; @@ -1329,7 +1329,7 @@ BPF_PROG_RUN_ARRAY_CG(const struct bpf_prog_array __rcu *array_rcu, old_run_ctx = bpf_set_run_ctx(&run_ctx.run_ctx); while ((prog = READ_ONCE(item->prog))) { run_ctx.prog_item = item; - if (!run_prog(prog, ctx)) + if (!run_prog(prog, ctx) && !IS_ERR_VALUE((long)run_ctx.retval)) run_ctx.retval = -EPERM; item++; } @@ -1389,7 +1389,7 @@ out: * 0: NET_XMIT_SUCCESS skb should be transmitted * 1: NET_XMIT_DROP skb should be dropped and cn * 2: NET_XMIT_CN skb should be transmitted and cn - * 3: -EPERM skb should be dropped + * 3: -err skb should be dropped */ #define BPF_PROG_CGROUP_INET_EGRESS_RUN_ARRAY(array, ctx, func) \ ({ \ @@ -1398,10 +1398,12 @@ out: u32 _ret; \ _ret = BPF_PROG_RUN_ARRAY_CG_FLAGS(array, ctx, func, 0, &_flags); \ _cn = _flags & BPF_RET_SET_CN; \ + if (_ret && !IS_ERR_VALUE((long)_ret)) \ + _ret = -EFAULT; \ if (!_ret) \ _ret = (_cn ? NET_XMIT_CN : NET_XMIT_SUCCESS); \ else \ - _ret = (_cn ? NET_XMIT_DROP : -EPERM); \ + _ret = (_cn ? NET_XMIT_DROP : _ret); \ _ret; \ }) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index a9c96c21330a..fe2272defcd9 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -5033,6 +5033,22 @@ union bpf_attr { * * Return * The number of arguments of the traced function. + * + * int bpf_get_retval(void) + * Description + * Get the syscall's return value that will be returned to userspace. + * + * This helper is currently supported by cgroup programs only. + * Return + * The syscall's return value. + * + * int bpf_set_retval(int retval) + * Description + * Set the syscall's return value that will be returned to userspace. + * + * This helper is currently supported by cgroup programs only. + * Return + * 0 on success, or a negative error in case of failure. */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -5221,6 +5237,8 @@ union bpf_attr { FN(get_func_arg), \ FN(get_func_ret), \ FN(get_func_arg_cnt), \ + FN(get_retval), \ + FN(set_retval), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index b6fad0bbf5a7..279ebbed75a5 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -1044,7 +1044,7 @@ int cgroup_bpf_prog_query(const union bpf_attr *attr, * NET_XMIT_DROP (1) - drop packet and notify TCP to call cwr * NET_XMIT_CN (2) - continue with packet output and notify TCP * to call cwr - * -EPERM - drop packet + * -err - drop packet * * For ingress packets, this function will return -EPERM if any * attached program was found and if it returned != 1 during execution. @@ -1080,6 +1080,8 @@ int __cgroup_bpf_run_filter_skb(struct sock *sk, } else { ret = BPF_PROG_RUN_ARRAY_CG(cgrp->bpf.effective[atype], skb, __bpf_prog_run_save_cb, 0); + if (ret && !IS_ERR_VALUE((long)ret)) + ret = -EFAULT; } bpf_restore_data_end(skb, saved_data_end); __skb_pull(skb, offset); @@ -1205,6 +1207,36 @@ int __cgroup_bpf_check_dev_permission(short dev_type, u32 major, u32 minor, return ret; } +BPF_CALL_0(bpf_get_retval) +{ + struct bpf_cg_run_ctx *ctx = + container_of(current->bpf_ctx, struct bpf_cg_run_ctx, run_ctx); + + return ctx->retval; +} + +static const struct bpf_func_proto bpf_get_retval_proto = { + .func = bpf_get_retval, + .gpl_only = false, + .ret_type = RET_INTEGER, +}; + +BPF_CALL_1(bpf_set_retval, int, retval) +{ + struct bpf_cg_run_ctx *ctx = + container_of(current->bpf_ctx, struct bpf_cg_run_ctx, run_ctx); + + ctx->retval = retval; + return 0; +} + +static const struct bpf_func_proto bpf_set_retval_proto = { + .func = bpf_set_retval, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_ANYTHING, +}; + static const struct bpf_func_proto * cgroup_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) { @@ -1217,6 +1249,10 @@ cgroup_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_get_current_cgroup_id_proto; case BPF_FUNC_perf_event_output: return &bpf_event_output_data_proto; + case BPF_FUNC_get_retval: + return &bpf_get_retval_proto; + case BPF_FUNC_set_retval: + return &bpf_set_retval_proto; default: return bpf_base_func_proto(func_id); } diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index a9c96c21330a..fe2272defcd9 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -5033,6 +5033,22 @@ union bpf_attr { * * Return * The number of arguments of the traced function. + * + * int bpf_get_retval(void) + * Description + * Get the syscall's return value that will be returned to userspace. + * + * This helper is currently supported by cgroup programs only. + * Return + * The syscall's return value. + * + * int bpf_set_retval(int retval) + * Description + * Set the syscall's return value that will be returned to userspace. + * + * This helper is currently supported by cgroup programs only. + * Return + * 0 on success, or a negative error in case of failure. */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -5221,6 +5237,8 @@ union bpf_attr { FN(get_func_arg), \ FN(get_func_ret), \ FN(get_func_arg_cnt), \ + FN(get_retval), \ + FN(set_retval), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper -- cgit v1.2.3 From c2f2cdbeffda7b153c19e0f3d73149c41026c0db Mon Sep 17 00:00:00 2001 From: Lorenzo Bianconi Date: Fri, 21 Jan 2022 11:09:52 +0100 Subject: bpf: introduce BPF_F_XDP_HAS_FRAGS flag in prog_flags loading the ebpf program Introduce BPF_F_XDP_HAS_FRAGS and the related field in bpf_prog_aux in order to notify the driver the loaded program support xdp frags. Acked-by: Toke Hoiland-Jorgensen Acked-by: John Fastabend Signed-off-by: Lorenzo Bianconi Link: https://lore.kernel.org/r/db2e8075b7032a356003f407d1b0deb99adaa0ed.1642758637.git.lorenzo@kernel.org Signed-off-by: Alexei Starovoitov --- include/linux/bpf.h | 1 + include/uapi/linux/bpf.h | 5 +++++ kernel/bpf/syscall.c | 4 +++- tools/include/uapi/linux/bpf.h | 5 +++++ 4 files changed, 14 insertions(+), 1 deletion(-) (limited to 'tools/include/uapi') diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 80e3387ea3af..e93ed028a030 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -933,6 +933,7 @@ struct bpf_prog_aux { bool func_proto_unreliable; bool sleepable; bool tail_call_reachable; + bool xdp_has_frags; struct hlist_node tramp_hlist; /* BTF_KIND_FUNC_PROTO for valid attach_btf_id */ const struct btf_type *attach_func_proto; diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index fe2272defcd9..945649c67e03 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -1113,6 +1113,11 @@ enum bpf_link_type { */ #define BPF_F_SLEEPABLE (1U << 4) +/* If BPF_F_XDP_HAS_FRAGS is used in BPF_PROG_LOAD command, the loaded program + * fully support xdp frags. + */ +#define BPF_F_XDP_HAS_FRAGS (1U << 5) + /* When BPF ldimm64's insn[0].src_reg != 0 then this can have * the following extensions: * diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 9e0631f091a6..f29090643c6e 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -2217,7 +2217,8 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr) BPF_F_ANY_ALIGNMENT | BPF_F_TEST_STATE_FREQ | BPF_F_SLEEPABLE | - BPF_F_TEST_RND_HI32)) + BPF_F_TEST_RND_HI32 | + BPF_F_XDP_HAS_FRAGS)) return -EINVAL; if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && @@ -2303,6 +2304,7 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr) prog->aux->dst_prog = dst_prog; prog->aux->offload_requested = !!attr->prog_ifindex; prog->aux->sleepable = attr->prog_flags & BPF_F_SLEEPABLE; + prog->aux->xdp_has_frags = attr->prog_flags & BPF_F_XDP_HAS_FRAGS; err = security_bpf_prog_alloc(prog->aux); if (err) diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index fe2272defcd9..945649c67e03 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -1113,6 +1113,11 @@ enum bpf_link_type { */ #define BPF_F_SLEEPABLE (1U << 4) +/* If BPF_F_XDP_HAS_FRAGS is used in BPF_PROG_LOAD command, the loaded program + * fully support xdp frags. + */ +#define BPF_F_XDP_HAS_FRAGS (1U << 5) + /* When BPF ldimm64's insn[0].src_reg != 0 then this can have * the following extensions: * -- cgit v1.2.3 From 0165cc817075cf701e4289838f1d925ff1911b3e Mon Sep 17 00:00:00 2001 From: Lorenzo Bianconi Date: Fri, 21 Jan 2022 11:09:54 +0100 Subject: bpf: introduce bpf_xdp_get_buff_len helper Introduce bpf_xdp_get_buff_len helper in order to return the xdp buffer total size (linear and paged area) Acked-by: Toke Hoiland-Jorgensen Acked-by: John Fastabend Signed-off-by: Lorenzo Bianconi Link: https://lore.kernel.org/r/aac9ac3504c84026cf66a3c71b7c5ae89bc991be.1642758637.git.lorenzo@kernel.org Signed-off-by: Alexei Starovoitov --- include/net/xdp.h | 14 ++++++++++++++ include/uapi/linux/bpf.h | 7 +++++++ net/core/filter.c | 15 +++++++++++++++ tools/include/uapi/linux/bpf.h | 7 +++++++ 4 files changed, 43 insertions(+) (limited to 'tools/include/uapi') diff --git a/include/net/xdp.h b/include/net/xdp.h index 8463dea8b4db..52b593321956 100644 --- a/include/net/xdp.h +++ b/include/net/xdp.h @@ -145,6 +145,20 @@ xdp_get_shared_info_from_buff(struct xdp_buff *xdp) return (struct skb_shared_info *)xdp_data_hard_end(xdp); } +static __always_inline unsigned int xdp_get_buff_len(struct xdp_buff *xdp) +{ + unsigned int len = xdp->data_end - xdp->data; + struct skb_shared_info *sinfo; + + if (likely(!xdp_buff_has_frags(xdp))) + goto out; + + sinfo = xdp_get_shared_info_from_buff(xdp); + len += sinfo->xdp_frags_size; +out: + return len; +} + struct xdp_frame { void *data; u16 len; diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 945649c67e03..5a28772063f6 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -5054,6 +5054,12 @@ union bpf_attr { * This helper is currently supported by cgroup programs only. * Return * 0 on success, or a negative error in case of failure. + * + * u64 bpf_xdp_get_buff_len(struct xdp_buff *xdp_md) + * Description + * Get the total size of a given xdp buff (linear and paged area) + * Return + * The total size of a given xdp buffer. */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -5244,6 +5250,7 @@ union bpf_attr { FN(get_func_arg_cnt), \ FN(get_retval), \ FN(set_retval), \ + FN(xdp_get_buff_len), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper diff --git a/net/core/filter.c b/net/core/filter.c index f73a84c75970..a7f03bbca465 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -3783,6 +3783,19 @@ static const struct bpf_func_proto sk_skb_change_head_proto = { .arg2_type = ARG_ANYTHING, .arg3_type = ARG_ANYTHING, }; + +BPF_CALL_1(bpf_xdp_get_buff_len, struct xdp_buff*, xdp) +{ + return xdp_get_buff_len(xdp); +} + +static const struct bpf_func_proto bpf_xdp_get_buff_len_proto = { + .func = bpf_xdp_get_buff_len, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, +}; + static unsigned long xdp_get_metalen(const struct xdp_buff *xdp) { return xdp_data_meta_unsupported(xdp) ? 0 : @@ -7533,6 +7546,8 @@ xdp_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_xdp_redirect_map_proto; case BPF_FUNC_xdp_adjust_tail: return &bpf_xdp_adjust_tail_proto; + case BPF_FUNC_xdp_get_buff_len: + return &bpf_xdp_get_buff_len_proto; case BPF_FUNC_fib_lookup: return &bpf_xdp_fib_lookup_proto; case BPF_FUNC_check_mtu: diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 945649c67e03..5a28772063f6 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -5054,6 +5054,12 @@ union bpf_attr { * This helper is currently supported by cgroup programs only. * Return * 0 on success, or a negative error in case of failure. + * + * u64 bpf_xdp_get_buff_len(struct xdp_buff *xdp_md) + * Description + * Get the total size of a given xdp buff (linear and paged area) + * Return + * The total size of a given xdp buffer. */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -5244,6 +5250,7 @@ union bpf_attr { FN(get_func_arg_cnt), \ FN(get_retval), \ FN(set_retval), \ + FN(xdp_get_buff_len), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper -- cgit v1.2.3 From 3f364222d032eea6b245780e845ad213dab28cdd Mon Sep 17 00:00:00 2001 From: Lorenzo Bianconi Date: Fri, 21 Jan 2022 11:10:03 +0100 Subject: net: xdp: introduce bpf_xdp_pointer utility routine Similar to skb_header_pointer, introduce bpf_xdp_pointer utility routine to return a pointer to a given position in the xdp_buff if the requested area (offset + len) is contained in a contiguous memory area otherwise it will be copied in a bounce buffer provided by the caller. Similar to the tc counterpart, introduce the two following xdp helpers: - bpf_xdp_load_bytes - bpf_xdp_store_bytes Reviewed-by: Eelco Chaudron Acked-by: Toke Hoiland-Jorgensen Acked-by: John Fastabend Acked-by: Jakub Kicinski Signed-off-by: Lorenzo Bianconi Link: https://lore.kernel.org/r/ab285c1efdd5b7a9d361348b1e7d3ef49f6382b3.1642758637.git.lorenzo@kernel.org Signed-off-by: Alexei Starovoitov --- include/uapi/linux/bpf.h | 18 +++++ net/core/filter.c | 176 ++++++++++++++++++++++++++++++++--------- tools/include/uapi/linux/bpf.h | 18 +++++ 3 files changed, 174 insertions(+), 38 deletions(-) (limited to 'tools/include/uapi') diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 5a28772063f6..16a7574292a5 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -5060,6 +5060,22 @@ union bpf_attr { * Get the total size of a given xdp buff (linear and paged area) * Return * The total size of a given xdp buffer. + * + * long bpf_xdp_load_bytes(struct xdp_buff *xdp_md, u32 offset, void *buf, u32 len) + * Description + * This helper is provided as an easy way to load data from a + * xdp buffer. It can be used to load *len* bytes from *offset* from + * the frame associated to *xdp_md*, into the buffer pointed by + * *buf*. + * Return + * 0 on success, or a negative error in case of failure. + * + * long bpf_xdp_store_bytes(struct xdp_buff *xdp_md, u32 offset, void *buf, u32 len) + * Description + * Store *len* bytes from buffer *buf* into the frame + * associated to *xdp_md*, at *offset*. + * Return + * 0 on success, or a negative error in case of failure. */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -5251,6 +5267,8 @@ union bpf_attr { FN(get_retval), \ FN(set_retval), \ FN(xdp_get_buff_len), \ + FN(xdp_load_bytes), \ + FN(xdp_store_bytes), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper diff --git a/net/core/filter.c b/net/core/filter.c index e4ce138bf925..945ccaaab3cb 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -3839,6 +3839,138 @@ static const struct bpf_func_proto bpf_xdp_adjust_head_proto = { .arg2_type = ARG_ANYTHING, }; +static void bpf_xdp_copy_buf(struct xdp_buff *xdp, unsigned long off, + void *buf, unsigned long len, bool flush) +{ + unsigned long ptr_len, ptr_off = 0; + skb_frag_t *next_frag, *end_frag; + struct skb_shared_info *sinfo; + void *src, *dst; + u8 *ptr_buf; + + if (likely(xdp->data_end - xdp->data >= off + len)) { + src = flush ? buf : xdp->data + off; + dst = flush ? xdp->data + off : buf; + memcpy(dst, src, len); + return; + } + + sinfo = xdp_get_shared_info_from_buff(xdp); + end_frag = &sinfo->frags[sinfo->nr_frags]; + next_frag = &sinfo->frags[0]; + + ptr_len = xdp->data_end - xdp->data; + ptr_buf = xdp->data; + + while (true) { + if (off < ptr_off + ptr_len) { + unsigned long copy_off = off - ptr_off; + unsigned long copy_len = min(len, ptr_len - copy_off); + + src = flush ? buf : ptr_buf + copy_off; + dst = flush ? ptr_buf + copy_off : buf; + memcpy(dst, src, copy_len); + + off += copy_len; + len -= copy_len; + buf += copy_len; + } + + if (!len || next_frag == end_frag) + break; + + ptr_off += ptr_len; + ptr_buf = skb_frag_address(next_frag); + ptr_len = skb_frag_size(next_frag); + next_frag++; + } +} + +static void *bpf_xdp_pointer(struct xdp_buff *xdp, u32 offset, u32 len) +{ + struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp); + u32 size = xdp->data_end - xdp->data; + void *addr = xdp->data; + int i; + + if (unlikely(offset > 0xffff || len > 0xffff)) + return ERR_PTR(-EFAULT); + + if (offset + len > xdp_get_buff_len(xdp)) + return ERR_PTR(-EINVAL); + + if (offset < size) /* linear area */ + goto out; + + offset -= size; + for (i = 0; i < sinfo->nr_frags; i++) { /* paged area */ + u32 frag_size = skb_frag_size(&sinfo->frags[i]); + + if (offset < frag_size) { + addr = skb_frag_address(&sinfo->frags[i]); + size = frag_size; + break; + } + offset -= frag_size; + } +out: + return offset + len < size ? addr + offset : NULL; +} + +BPF_CALL_4(bpf_xdp_load_bytes, struct xdp_buff *, xdp, u32, offset, + void *, buf, u32, len) +{ + void *ptr; + + ptr = bpf_xdp_pointer(xdp, offset, len); + if (IS_ERR(ptr)) + return PTR_ERR(ptr); + + if (!ptr) + bpf_xdp_copy_buf(xdp, offset, buf, len, false); + else + memcpy(buf, ptr, len); + + return 0; +} + +static const struct bpf_func_proto bpf_xdp_load_bytes_proto = { + .func = bpf_xdp_load_bytes, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, + .arg2_type = ARG_ANYTHING, + .arg3_type = ARG_PTR_TO_UNINIT_MEM, + .arg4_type = ARG_CONST_SIZE, +}; + +BPF_CALL_4(bpf_xdp_store_bytes, struct xdp_buff *, xdp, u32, offset, + void *, buf, u32, len) +{ + void *ptr; + + ptr = bpf_xdp_pointer(xdp, offset, len); + if (IS_ERR(ptr)) + return PTR_ERR(ptr); + + if (!ptr) + bpf_xdp_copy_buf(xdp, offset, buf, len, true); + else + memcpy(ptr, buf, len); + + return 0; +} + +static const struct bpf_func_proto bpf_xdp_store_bytes_proto = { + .func = bpf_xdp_store_bytes, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, + .arg2_type = ARG_ANYTHING, + .arg3_type = ARG_PTR_TO_UNINIT_MEM, + .arg4_type = ARG_CONST_SIZE, +}; + static int bpf_xdp_frags_increase_tail(struct xdp_buff *xdp, int offset) { struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp); @@ -4677,48 +4809,12 @@ static const struct bpf_func_proto bpf_sk_ancestor_cgroup_id_proto = { }; #endif -static unsigned long bpf_xdp_copy(void *dst_buff, const void *ctx, +static unsigned long bpf_xdp_copy(void *dst, const void *ctx, unsigned long off, unsigned long len) { struct xdp_buff *xdp = (struct xdp_buff *)ctx; - unsigned long ptr_len, ptr_off = 0; - skb_frag_t *next_frag, *end_frag; - struct skb_shared_info *sinfo; - u8 *ptr_buf; - - if (likely(xdp->data_end - xdp->data >= off + len)) { - memcpy(dst_buff, xdp->data + off, len); - return 0; - } - - sinfo = xdp_get_shared_info_from_buff(xdp); - end_frag = &sinfo->frags[sinfo->nr_frags]; - next_frag = &sinfo->frags[0]; - - ptr_len = xdp->data_end - xdp->data; - ptr_buf = xdp->data; - - while (true) { - if (off < ptr_off + ptr_len) { - unsigned long copy_off = off - ptr_off; - unsigned long copy_len = min(len, ptr_len - copy_off); - - memcpy(dst_buff, ptr_buf + copy_off, copy_len); - - off += copy_len; - len -= copy_len; - dst_buff += copy_len; - } - - if (!len || next_frag == end_frag) - break; - - ptr_off += ptr_len; - ptr_buf = skb_frag_address(next_frag); - ptr_len = skb_frag_size(next_frag); - next_frag++; - } + bpf_xdp_copy_buf(xdp, off, dst, len, false); return 0; } @@ -7660,6 +7756,10 @@ xdp_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_xdp_adjust_tail_proto; case BPF_FUNC_xdp_get_buff_len: return &bpf_xdp_get_buff_len_proto; + case BPF_FUNC_xdp_load_bytes: + return &bpf_xdp_load_bytes_proto; + case BPF_FUNC_xdp_store_bytes: + return &bpf_xdp_store_bytes_proto; case BPF_FUNC_fib_lookup: return &bpf_xdp_fib_lookup_proto; case BPF_FUNC_check_mtu: diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 5a28772063f6..16a7574292a5 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -5060,6 +5060,22 @@ union bpf_attr { * Get the total size of a given xdp buff (linear and paged area) * Return * The total size of a given xdp buffer. + * + * long bpf_xdp_load_bytes(struct xdp_buff *xdp_md, u32 offset, void *buf, u32 len) + * Description + * This helper is provided as an easy way to load data from a + * xdp buffer. It can be used to load *len* bytes from *offset* from + * the frame associated to *xdp_md*, into the buffer pointed by + * *buf*. + * Return + * 0 on success, or a negative error in case of failure. + * + * long bpf_xdp_store_bytes(struct xdp_buff *xdp_md, u32 offset, void *buf, u32 len) + * Description + * Store *len* bytes from buffer *buf* into the frame + * associated to *xdp_md*, at *offset*. + * Return + * 0 on success, or a negative error in case of failure. */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -5251,6 +5267,8 @@ union bpf_attr { FN(get_retval), \ FN(set_retval), \ FN(xdp_get_buff_len), \ + FN(xdp_load_bytes), \ + FN(xdp_store_bytes), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper -- cgit v1.2.3 From 376040e47334c6dc6a939a32197acceb00fe4acf Mon Sep 17 00:00:00 2001 From: Kenny Yu Date: Mon, 24 Jan 2022 10:54:01 -0800 Subject: bpf: Add bpf_copy_from_user_task() helper This adds a helper for bpf programs to read the memory of other tasks. As an example use case at Meta, we are using a bpf task iterator program and this new helper to print C++ async stack traces for all threads of a given process. Signed-off-by: Kenny Yu Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/r/20220124185403.468466-3-kennyyu@fb.com Signed-off-by: Alexei Starovoitov --- include/linux/bpf.h | 1 + include/uapi/linux/bpf.h | 11 +++++++++++ kernel/bpf/helpers.c | 34 ++++++++++++++++++++++++++++++++++ kernel/trace/bpf_trace.c | 2 ++ tools/include/uapi/linux/bpf.h | 11 +++++++++++ 5 files changed, 59 insertions(+) (limited to 'tools/include/uapi') diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 8c92c974bd12..394305a5e02f 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -2243,6 +2243,7 @@ extern const struct bpf_func_proto bpf_kallsyms_lookup_name_proto; extern const struct bpf_func_proto bpf_find_vma_proto; extern const struct bpf_func_proto bpf_loop_proto; extern const struct bpf_func_proto bpf_strncmp_proto; +extern const struct bpf_func_proto bpf_copy_from_user_task_proto; const struct bpf_func_proto *tracing_prog_func_proto( enum bpf_func_id func_id, const struct bpf_prog *prog); diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 16a7574292a5..4a2f7041ebae 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -5076,6 +5076,16 @@ union bpf_attr { * associated to *xdp_md*, at *offset*. * Return * 0 on success, or a negative error in case of failure. + * + * long bpf_copy_from_user_task(void *dst, u32 size, const void *user_ptr, struct task_struct *tsk, u64 flags) + * Description + * Read *size* bytes from user space address *user_ptr* in *tsk*'s + * address space, and stores the data in *dst*. *flags* is not + * used yet and is provided for future extensibility. This helper + * can only be used by sleepable programs. + * Return + * 0 on success, or a negative error in case of failure. On error + * *dst* buffer is zeroed out. */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -5269,6 +5279,7 @@ union bpf_attr { FN(xdp_get_buff_len), \ FN(xdp_load_bytes), \ FN(xdp_store_bytes), \ + FN(copy_from_user_task), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 01cfdf40c838..ed2780b76cc1 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -16,6 +16,7 @@ #include #include #include +#include #include "../../lib/kstrtox.h" @@ -671,6 +672,39 @@ const struct bpf_func_proto bpf_copy_from_user_proto = { .arg3_type = ARG_ANYTHING, }; +BPF_CALL_5(bpf_copy_from_user_task, void *, dst, u32, size, + const void __user *, user_ptr, struct task_struct *, tsk, u64, flags) +{ + int ret; + + /* flags is not used yet */ + if (unlikely(flags)) + return -EINVAL; + + if (unlikely(!size)) + return 0; + + ret = access_process_vm(tsk, (unsigned long)user_ptr, dst, size, 0); + if (ret == size) + return 0; + + memset(dst, 0, size); + /* Return -EFAULT for partial read */ + return ret < 0 ? ret : -EFAULT; +} + +const struct bpf_func_proto bpf_copy_from_user_task_proto = { + .func = bpf_copy_from_user_task, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_UNINIT_MEM, + .arg2_type = ARG_CONST_SIZE_OR_ZERO, + .arg3_type = ARG_ANYTHING, + .arg4_type = ARG_PTR_TO_BTF_ID, + .arg4_btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK], + .arg5_type = ARG_ANYTHING +}; + BPF_CALL_2(bpf_per_cpu_ptr, const void *, ptr, u32, cpu) { if (cpu >= nr_cpu_ids) diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 06a9e220069e..a2024ba32a20 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -1235,6 +1235,8 @@ bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_get_task_stack_proto; case BPF_FUNC_copy_from_user: return prog->aux->sleepable ? &bpf_copy_from_user_proto : NULL; + case BPF_FUNC_copy_from_user_task: + return prog->aux->sleepable ? &bpf_copy_from_user_task_proto : NULL; case BPF_FUNC_snprintf_btf: return &bpf_snprintf_btf_proto; case BPF_FUNC_per_cpu_ptr: diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 16a7574292a5..4a2f7041ebae 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -5076,6 +5076,16 @@ union bpf_attr { * associated to *xdp_md*, at *offset*. * Return * 0 on success, or a negative error in case of failure. + * + * long bpf_copy_from_user_task(void *dst, u32 size, const void *user_ptr, struct task_struct *tsk, u64 flags) + * Description + * Read *size* bytes from user space address *user_ptr* in *tsk*'s + * address space, and stores the data in *dst*. *flags* is not + * used yet and is provided for future extensibility. This helper + * can only be used by sleepable programs. + * Return + * 0 on success, or a negative error in case of failure. On error + * *dst* buffer is zeroed out. */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -5269,6 +5279,7 @@ union bpf_attr { FN(xdp_get_buff_len), \ FN(xdp_load_bytes), \ FN(xdp_store_bytes), \ + FN(copy_from_user_task), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper -- cgit v1.2.3 From 8f50f16ff39dd4e2d43d1548ca66925652f8aff7 Mon Sep 17 00:00:00 2001 From: Jakub Sitnicki Date: Sun, 30 Jan 2022 12:55:18 +0100 Subject: selftests/bpf: Extend verifier and bpf_sock tests for dst_port loads Add coverage to the verifier tests and tests for reading bpf_sock fields to ensure that 32-bit, 16-bit, and 8-bit loads from dst_port field are allowed only at intended offsets and produce expected values. While 16-bit and 8-bit access to dst_port field is straight-forward, 32-bit wide loads need be allowed and produce a zero-padded 16-bit value for backward compatibility. Signed-off-by: Jakub Sitnicki Link: https://lore.kernel.org/r/20220130115518.213259-3-jakub@cloudflare.com Signed-off-by: Alexei Starovoitov --- tools/include/uapi/linux/bpf.h | 3 +- .../testing/selftests/bpf/prog_tests/sock_fields.c | 58 +++++++++++----- .../testing/selftests/bpf/progs/test_sock_fields.c | 41 +++++++++++ tools/testing/selftests/bpf/verifier/sock.c | 81 +++++++++++++++++++++- 4 files changed, 162 insertions(+), 21 deletions(-) (limited to 'tools/include/uapi') diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 4a2f7041ebae..a7f0ddedac1f 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -5574,7 +5574,8 @@ struct bpf_sock { __u32 src_ip4; __u32 src_ip6[4]; __u32 src_port; /* host byte order */ - __u32 dst_port; /* network byte order */ + __be16 dst_port; /* network byte order */ + __u16 :16; /* zero padding */ __u32 dst_ip4; __u32 dst_ip6[4]; __u32 state; diff --git a/tools/testing/selftests/bpf/prog_tests/sock_fields.c b/tools/testing/selftests/bpf/prog_tests/sock_fields.c index 9fc040eaa482..9d211b5c22c4 100644 --- a/tools/testing/selftests/bpf/prog_tests/sock_fields.c +++ b/tools/testing/selftests/bpf/prog_tests/sock_fields.c @@ -1,9 +1,11 @@ // SPDX-License-Identifier: GPL-2.0 /* Copyright (c) 2019 Facebook */ +#define _GNU_SOURCE #include #include #include +#include #include #include #include @@ -20,6 +22,7 @@ enum bpf_linum_array_idx { EGRESS_LINUM_IDX, INGRESS_LINUM_IDX, + READ_SK_DST_PORT_LINUM_IDX, __NR_BPF_LINUM_ARRAY_IDX, }; @@ -42,8 +45,16 @@ static __u64 child_cg_id; static int linum_map_fd; static __u32 duration; -static __u32 egress_linum_idx = EGRESS_LINUM_IDX; -static __u32 ingress_linum_idx = INGRESS_LINUM_IDX; +static bool create_netns(void) +{ + if (!ASSERT_OK(unshare(CLONE_NEWNET), "create netns")) + return false; + + if (!ASSERT_OK(system("ip link set dev lo up"), "bring up lo")) + return false; + + return true; +} static void print_sk(const struct bpf_sock *sk, const char *prefix) { @@ -91,19 +102,24 @@ static void check_result(void) { struct bpf_tcp_sock srv_tp, cli_tp, listen_tp; struct bpf_sock srv_sk, cli_sk, listen_sk; - __u32 ingress_linum, egress_linum; + __u32 idx, ingress_linum, egress_linum, linum; int err; - err = bpf_map_lookup_elem(linum_map_fd, &egress_linum_idx, - &egress_linum); + idx = EGRESS_LINUM_IDX; + err = bpf_map_lookup_elem(linum_map_fd, &idx, &egress_linum); CHECK(err < 0, "bpf_map_lookup_elem(linum_map_fd)", "err:%d errno:%d\n", err, errno); - err = bpf_map_lookup_elem(linum_map_fd, &ingress_linum_idx, - &ingress_linum); + idx = INGRESS_LINUM_IDX; + err = bpf_map_lookup_elem(linum_map_fd, &idx, &ingress_linum); CHECK(err < 0, "bpf_map_lookup_elem(linum_map_fd)", "err:%d errno:%d\n", err, errno); + idx = READ_SK_DST_PORT_LINUM_IDX; + err = bpf_map_lookup_elem(linum_map_fd, &idx, &linum); + ASSERT_OK(err, "bpf_map_lookup_elem(linum_map_fd, READ_SK_DST_PORT_IDX)"); + ASSERT_EQ(linum, 0, "failure in read_sk_dst_port on line"); + memcpy(&srv_sk, &skel->bss->srv_sk, sizeof(srv_sk)); memcpy(&srv_tp, &skel->bss->srv_tp, sizeof(srv_tp)); memcpy(&cli_sk, &skel->bss->cli_sk, sizeof(cli_sk)); @@ -262,7 +278,7 @@ static void test(void) char buf[DATA_LEN]; /* Prepare listen_fd */ - listen_fd = start_server(AF_INET6, SOCK_STREAM, "::1", 0, 0); + listen_fd = start_server(AF_INET6, SOCK_STREAM, "::1", 0xcafe, 0); /* start_server() has logged the error details */ if (CHECK_FAIL(listen_fd == -1)) goto done; @@ -330,8 +346,12 @@ done: void serial_test_sock_fields(void) { - struct bpf_link *egress_link = NULL, *ingress_link = NULL; int parent_cg_fd = -1, child_cg_fd = -1; + struct bpf_link *link; + + /* Use a dedicated netns to have a fixed listen port */ + if (!create_netns()) + return; /* Create a cgroup, get fd, and join it */ parent_cg_fd = test__join_cgroup(PARENT_CGROUP); @@ -352,15 +372,20 @@ void serial_test_sock_fields(void) if (CHECK(!skel, "test_sock_fields__open_and_load", "failed\n")) goto done; - egress_link = bpf_program__attach_cgroup(skel->progs.egress_read_sock_fields, - child_cg_fd); - if (!ASSERT_OK_PTR(egress_link, "attach_cgroup(egress)")) + link = bpf_program__attach_cgroup(skel->progs.egress_read_sock_fields, child_cg_fd); + if (!ASSERT_OK_PTR(link, "attach_cgroup(egress_read_sock_fields)")) + goto done; + skel->links.egress_read_sock_fields = link; + + link = bpf_program__attach_cgroup(skel->progs.ingress_read_sock_fields, child_cg_fd); + if (!ASSERT_OK_PTR(link, "attach_cgroup(ingress_read_sock_fields)")) goto done; + skel->links.ingress_read_sock_fields = link; - ingress_link = bpf_program__attach_cgroup(skel->progs.ingress_read_sock_fields, - child_cg_fd); - if (!ASSERT_OK_PTR(ingress_link, "attach_cgroup(ingress)")) + link = bpf_program__attach_cgroup(skel->progs.read_sk_dst_port, child_cg_fd); + if (!ASSERT_OK_PTR(link, "attach_cgroup(read_sk_dst_port")) goto done; + skel->links.read_sk_dst_port = link; linum_map_fd = bpf_map__fd(skel->maps.linum_map); sk_pkt_out_cnt_fd = bpf_map__fd(skel->maps.sk_pkt_out_cnt); @@ -369,8 +394,7 @@ void serial_test_sock_fields(void) test(); done: - bpf_link__destroy(egress_link); - bpf_link__destroy(ingress_link); + test_sock_fields__detach(skel); test_sock_fields__destroy(skel); if (child_cg_fd >= 0) close(child_cg_fd); diff --git a/tools/testing/selftests/bpf/progs/test_sock_fields.c b/tools/testing/selftests/bpf/progs/test_sock_fields.c index 81b57b9aaaea..246f1f001813 100644 --- a/tools/testing/selftests/bpf/progs/test_sock_fields.c +++ b/tools/testing/selftests/bpf/progs/test_sock_fields.c @@ -12,6 +12,7 @@ enum bpf_linum_array_idx { EGRESS_LINUM_IDX, INGRESS_LINUM_IDX, + READ_SK_DST_PORT_LINUM_IDX, __NR_BPF_LINUM_ARRAY_IDX, }; @@ -250,4 +251,44 @@ int ingress_read_sock_fields(struct __sk_buff *skb) return CG_OK; } +static __noinline bool sk_dst_port__load_word(struct bpf_sock *sk) +{ + __u32 *word = (__u32 *)&sk->dst_port; + return word[0] == bpf_htonl(0xcafe0000); +} + +static __noinline bool sk_dst_port__load_half(struct bpf_sock *sk) +{ + __u16 *half = (__u16 *)&sk->dst_port; + return half[0] == bpf_htons(0xcafe); +} + +static __noinline bool sk_dst_port__load_byte(struct bpf_sock *sk) +{ + __u8 *byte = (__u8 *)&sk->dst_port; + return byte[0] == 0xca && byte[1] == 0xfe; +} + +SEC("cgroup_skb/egress") +int read_sk_dst_port(struct __sk_buff *skb) +{ + __u32 linum, linum_idx; + struct bpf_sock *sk; + + linum_idx = READ_SK_DST_PORT_LINUM_IDX; + + sk = skb->sk; + if (!sk) + RET_LOG(); + + if (!sk_dst_port__load_word(sk)) + RET_LOG(); + if (!sk_dst_port__load_half(sk)) + RET_LOG(); + if (!sk_dst_port__load_byte(sk)) + RET_LOG(); + + return CG_OK; +} + char _license[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/verifier/sock.c b/tools/testing/selftests/bpf/verifier/sock.c index ce13ece08d51..8c224eac93df 100644 --- a/tools/testing/selftests/bpf/verifier/sock.c +++ b/tools/testing/selftests/bpf/verifier/sock.c @@ -121,7 +121,25 @@ .result = ACCEPT, }, { - "sk_fullsock(skb->sk): sk->dst_port [narrow load]", + "sk_fullsock(skb->sk): sk->dst_port [word load] (backward compatibility)", + .insns = { + BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_1, offsetof(struct __sk_buff, sk)), + BPF_JMP_IMM(BPF_JNE, BPF_REG_1, 0, 2), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + BPF_EMIT_CALL(BPF_FUNC_sk_fullsock), + BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 2), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_0, offsetof(struct bpf_sock, dst_port)), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_CGROUP_SKB, + .result = ACCEPT, +}, +{ + "sk_fullsock(skb->sk): sk->dst_port [half load]", .insns = { BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_1, offsetof(struct __sk_buff, sk)), BPF_JMP_IMM(BPF_JNE, BPF_REG_1, 0, 2), @@ -139,7 +157,64 @@ .result = ACCEPT, }, { - "sk_fullsock(skb->sk): sk->dst_port [load 2nd byte]", + "sk_fullsock(skb->sk): sk->dst_port [half load] (invalid)", + .insns = { + BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_1, offsetof(struct __sk_buff, sk)), + BPF_JMP_IMM(BPF_JNE, BPF_REG_1, 0, 2), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + BPF_EMIT_CALL(BPF_FUNC_sk_fullsock), + BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 2), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_0, offsetof(struct bpf_sock, dst_port) + 2), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_CGROUP_SKB, + .result = REJECT, + .errstr = "invalid sock access", +}, +{ + "sk_fullsock(skb->sk): sk->dst_port [byte load]", + .insns = { + BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_1, offsetof(struct __sk_buff, sk)), + BPF_JMP_IMM(BPF_JNE, BPF_REG_1, 0, 2), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + BPF_EMIT_CALL(BPF_FUNC_sk_fullsock), + BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 2), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + BPF_LDX_MEM(BPF_B, BPF_REG_2, BPF_REG_0, offsetof(struct bpf_sock, dst_port)), + BPF_LDX_MEM(BPF_B, BPF_REG_2, BPF_REG_0, offsetof(struct bpf_sock, dst_port) + 1), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_CGROUP_SKB, + .result = ACCEPT, +}, +{ + "sk_fullsock(skb->sk): sk->dst_port [byte load] (invalid)", + .insns = { + BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_1, offsetof(struct __sk_buff, sk)), + BPF_JMP_IMM(BPF_JNE, BPF_REG_1, 0, 2), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + BPF_EMIT_CALL(BPF_FUNC_sk_fullsock), + BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 2), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_0, offsetof(struct bpf_sock, dst_port) + 2), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_CGROUP_SKB, + .result = REJECT, + .errstr = "invalid sock access", +}, +{ + "sk_fullsock(skb->sk): past sk->dst_port [half load] (invalid)", .insns = { BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_1, offsetof(struct __sk_buff, sk)), BPF_JMP_IMM(BPF_JNE, BPF_REG_1, 0, 2), @@ -149,7 +224,7 @@ BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 2), BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), - BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_0, offsetof(struct bpf_sock, dst_port) + 1), + BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_0, offsetofend(struct bpf_sock, dst_port)), BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), }, -- cgit v1.2.3 From 2ed0dc5937d38f282841d22c5a5354ec264c7b8d Mon Sep 17 00:00:00 2001 From: Jakub Sitnicki Date: Wed, 9 Feb 2022 19:43:33 +0100 Subject: selftests/bpf: Cover 4-byte load from remote_port in bpf_sk_lookup Extend the context access tests for sk_lookup prog to cover the surprising case of a 4-byte load from the remote_port field, where the expected value is actually shifted by 16 bits. Signed-off-by: Jakub Sitnicki Signed-off-by: Alexei Starovoitov Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20220209184333.654927-3-jakub@cloudflare.com --- tools/include/uapi/linux/bpf.h | 3 ++- tools/testing/selftests/bpf/progs/test_sk_lookup.c | 6 ++++++ 2 files changed, 8 insertions(+), 1 deletion(-) (limited to 'tools/include/uapi') diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index a7f0ddedac1f..afe3d0d7f5f2 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -6453,7 +6453,8 @@ struct bpf_sk_lookup { __u32 protocol; /* IP protocol (IPPROTO_TCP, IPPROTO_UDP) */ __u32 remote_ip4; /* Network byte order */ __u32 remote_ip6[4]; /* Network byte order */ - __u32 remote_port; /* Network byte order */ + __be16 remote_port; /* Network byte order */ + __u16 :16; /* Zero padding */ __u32 local_ip4; /* Network byte order */ __u32 local_ip6[4]; /* Network byte order */ __u32 local_port; /* Host byte order */ diff --git a/tools/testing/selftests/bpf/progs/test_sk_lookup.c b/tools/testing/selftests/bpf/progs/test_sk_lookup.c index 83b0aaa52ef7..bf5b7caefdd0 100644 --- a/tools/testing/selftests/bpf/progs/test_sk_lookup.c +++ b/tools/testing/selftests/bpf/progs/test_sk_lookup.c @@ -392,6 +392,7 @@ int ctx_narrow_access(struct bpf_sk_lookup *ctx) { struct bpf_sock *sk; int err, family; + __u32 val_u32; bool v4; v4 = (ctx->family == AF_INET); @@ -418,6 +419,11 @@ int ctx_narrow_access(struct bpf_sk_lookup *ctx) if (LSW(ctx->remote_port, 0) != SRC_PORT) return SK_DROP; + /* Load from remote_port field with zero padding (backward compatibility) */ + val_u32 = *(__u32 *)&ctx->remote_port; + if (val_u32 != bpf_htonl(bpf_ntohs(SRC_PORT) << 16)) + return SK_DROP; + /* Narrow loads from local_port field. Expect DST_PORT. */ if (LSB(ctx->local_port, 0) != ((DST_PORT >> 0) & 0xff) || LSB(ctx->local_port, 1) != ((DST_PORT >> 8) & 0xff) || -- cgit v1.2.3 From 129e3c1bab24d27d0fa6e505a472345a92d7a2b0 Mon Sep 17 00:00:00 2001 From: Hangbin Liu Date: Mon, 21 Feb 2022 13:54:57 +0800 Subject: bonding: add new option ns_ip6_target This patch add a new bonding option ns_ip6_target, which correspond to the arp_ip_target. With this we set IPv6 targets and send IPv6 NS request to determine the health of the link. For other related options like the validation, we still use arp_validate, and will change to ns_validate later. Note: the sysfs configuration support was removed based on https://lore.kernel.org/netdev/8863.1645071997@famine Signed-off-by: Hangbin Liu Signed-off-by: David S. Miller --- Documentation/networking/bonding.rst | 11 ++++++ drivers/net/bonding/bond_netlink.c | 59 +++++++++++++++++++++++++++++ drivers/net/bonding/bond_options.c | 72 ++++++++++++++++++++++++++++++++++++ include/net/bond_options.h | 4 ++ include/net/bonding.h | 7 ++++ include/uapi/linux/if_link.h | 1 + tools/include/uapi/linux/if_link.h | 1 + 7 files changed, 155 insertions(+) (limited to 'tools/include/uapi') diff --git a/Documentation/networking/bonding.rst b/Documentation/networking/bonding.rst index ab98373535ea..525e6842dd33 100644 --- a/Documentation/networking/bonding.rst +++ b/Documentation/networking/bonding.rst @@ -313,6 +313,17 @@ arp_ip_target maximum number of targets that can be specified is 16. The default value is no IP addresses. +ns_ip6_target + + Specifies the IPv6 addresses to use as IPv6 monitoring peers when + arp_interval is > 0. These are the targets of the NS request + sent to determine the health of the link to the targets. + Specify these values in ffff:ffff::ffff:ffff format. Multiple IPv6 + addresses must be separated by a comma. At least one IPv6 + address must be given for NS/NA monitoring to function. The + maximum number of targets that can be specified is 16. The + default value is no IPv6 addresses. + arp_validate Specifies whether or not ARP probes and replies should be diff --git a/drivers/net/bonding/bond_netlink.c b/drivers/net/bonding/bond_netlink.c index 1007bf6d385d..f427fa1737c7 100644 --- a/drivers/net/bonding/bond_netlink.c +++ b/drivers/net/bonding/bond_netlink.c @@ -14,6 +14,7 @@ #include #include #include +#include static size_t bond_get_slave_size(const struct net_device *bond_dev, const struct net_device *slave_dev) @@ -111,6 +112,7 @@ static const struct nla_policy bond_policy[IFLA_BOND_MAX + 1] = { [IFLA_BOND_TLB_DYNAMIC_LB] = { .type = NLA_U8 }, [IFLA_BOND_PEER_NOTIF_DELAY] = { .type = NLA_U32 }, [IFLA_BOND_MISSED_MAX] = { .type = NLA_U8 }, + [IFLA_BOND_NS_IP6_TARGET] = { .type = NLA_NESTED }, }; static const struct nla_policy bond_slave_policy[IFLA_BOND_SLAVE_MAX + 1] = { @@ -272,6 +274,40 @@ static int bond_changelink(struct net_device *bond_dev, struct nlattr *tb[], if (err) return err; } +#if IS_ENABLED(CONFIG_IPV6) + if (data[IFLA_BOND_NS_IP6_TARGET]) { + struct nlattr *attr; + int i = 0, rem; + + bond_option_ns_ip6_targets_clear(bond); + nla_for_each_nested(attr, data[IFLA_BOND_NS_IP6_TARGET], rem) { + struct in6_addr addr6; + + if (nla_len(attr) < sizeof(addr6)) { + NL_SET_ERR_MSG(extack, "Invalid IPv6 address"); + return -EINVAL; + } + + addr6 = nla_get_in6_addr(attr); + + if (ipv6_addr_type(&addr6) & IPV6_ADDR_LINKLOCAL) { + NL_SET_ERR_MSG(extack, "Invalid IPv6 addr6"); + return -EINVAL; + } + + bond_opt_initextra(&newval, &addr6, sizeof(addr6)); + err = __bond_opt_set(bond, BOND_OPT_NS_TARGETS, + &newval); + if (err) + break; + i++; + } + if (i == 0 && bond->params.arp_interval) + netdev_warn(bond->dev, "Removing last ns target with arp_interval on\n"); + if (err) + return err; + } +#endif if (data[IFLA_BOND_ARP_VALIDATE]) { int arp_validate = nla_get_u32(data[IFLA_BOND_ARP_VALIDATE]); @@ -526,6 +562,9 @@ static size_t bond_get_size(const struct net_device *bond_dev) nla_total_size(sizeof(u8)) + /* IFLA_BOND_TLB_DYNAMIC_LB */ nla_total_size(sizeof(u32)) + /* IFLA_BOND_PEER_NOTIF_DELAY */ nla_total_size(sizeof(u8)) + /* IFLA_BOND_MISSED_MAX */ + /* IFLA_BOND_NS_IP6_TARGET */ + nla_total_size(sizeof(struct nlattr)) + + nla_total_size(sizeof(struct in6_addr)) * BOND_MAX_NS_TARGETS + 0; } @@ -603,6 +642,26 @@ static int bond_fill_info(struct sk_buff *skb, bond->params.arp_all_targets)) goto nla_put_failure; +#if IS_ENABLED(CONFIG_IPV6) + targets = nla_nest_start(skb, IFLA_BOND_NS_IP6_TARGET); + if (!targets) + goto nla_put_failure; + + targets_added = 0; + for (i = 0; i < BOND_MAX_NS_TARGETS; i++) { + if (!ipv6_addr_any(&bond->params.ns_targets[i])) { + if (nla_put_in6_addr(skb, i, &bond->params.ns_targets[i])) + goto nla_put_failure; + targets_added = 1; + } + } + + if (targets_added) + nla_nest_end(skb, targets); + else + nla_nest_cancel(skb, targets); +#endif + primary = rtnl_dereference(bond->primary_slave); if (primary && nla_put_u32(skb, IFLA_BOND_PRIMARY, primary->dev->ifindex)) diff --git a/drivers/net/bonding/bond_options.c b/drivers/net/bonding/bond_options.c index ab575135b626..64f7db2627ce 100644 --- a/drivers/net/bonding/bond_options.c +++ b/drivers/net/bonding/bond_options.c @@ -34,6 +34,10 @@ static int bond_option_arp_ip_target_add(struct bonding *bond, __be32 target); static int bond_option_arp_ip_target_rem(struct bonding *bond, __be32 target); static int bond_option_arp_ip_targets_set(struct bonding *bond, const struct bond_opt_value *newval); +#if IS_ENABLED(CONFIG_IPV6) +static int bond_option_ns_ip6_targets_set(struct bonding *bond, + const struct bond_opt_value *newval); +#endif static int bond_option_arp_validate_set(struct bonding *bond, const struct bond_opt_value *newval); static int bond_option_arp_all_targets_set(struct bonding *bond, @@ -295,6 +299,15 @@ static const struct bond_option bond_opts[BOND_OPT_LAST] = { .flags = BOND_OPTFLAG_RAWVAL, .set = bond_option_arp_ip_targets_set }, +#if IS_ENABLED(CONFIG_IPV6) + [BOND_OPT_NS_TARGETS] = { + .id = BOND_OPT_NS_TARGETS, + .name = "ns_ip6_target", + .desc = "NS targets in ffff:ffff::ffff:ffff form", + .flags = BOND_OPTFLAG_RAWVAL, + .set = bond_option_ns_ip6_targets_set + }, +#endif [BOND_OPT_DOWNDELAY] = { .id = BOND_OPT_DOWNDELAY, .name = "downdelay", @@ -1184,6 +1197,65 @@ static int bond_option_arp_ip_targets_set(struct bonding *bond, return ret; } +#if IS_ENABLED(CONFIG_IPV6) +static void _bond_options_ns_ip6_target_set(struct bonding *bond, int slot, + struct in6_addr *target, + unsigned long last_rx) +{ + struct in6_addr *targets = bond->params.ns_targets; + struct list_head *iter; + struct slave *slave; + + if (slot >= 0 && slot < BOND_MAX_NS_TARGETS) { + bond_for_each_slave(bond, slave, iter) + slave->target_last_arp_rx[slot] = last_rx; + targets[slot] = *target; + } +} + +void bond_option_ns_ip6_targets_clear(struct bonding *bond) +{ + struct in6_addr addr_any = in6addr_any; + int i; + + for (i = 0; i < BOND_MAX_NS_TARGETS; i++) + _bond_options_ns_ip6_target_set(bond, i, &addr_any, 0); +} + +static int bond_option_ns_ip6_targets_set(struct bonding *bond, + const struct bond_opt_value *newval) +{ + struct in6_addr *target = (struct in6_addr *)newval->extra; + struct in6_addr *targets = bond->params.ns_targets; + struct in6_addr addr_any = in6addr_any; + int index; + + if (!bond_is_ip6_target_ok(target)) { + netdev_err(bond->dev, "invalid NS target %pI6c specified for addition\n", + target); + return -EINVAL; + } + + if (bond_get_targets_ip6(targets, target) != -1) { /* dup */ + netdev_err(bond->dev, "NS target %pI6c is already present\n", + target); + return -EINVAL; + } + + index = bond_get_targets_ip6(targets, &addr_any); /* first free slot */ + if (index == -1) { + netdev_err(bond->dev, "NS target table is full!\n"); + return -EINVAL; + } + + netdev_dbg(bond->dev, "Adding NS target %pI6c\n", target); + + _bond_options_ns_ip6_target_set(bond, index, target, jiffies); + + return 0; +} +#endif + static int bond_option_arp_validate_set(struct bonding *bond, const struct bond_opt_value *newval) { diff --git a/include/net/bond_options.h b/include/net/bond_options.h index 286b29c6c451..61b49063791c 100644 --- a/include/net/bond_options.h +++ b/include/net/bond_options.h @@ -66,6 +66,7 @@ enum { BOND_OPT_PEER_NOTIF_DELAY, BOND_OPT_LACP_ACTIVE, BOND_OPT_MISSED_MAX, + BOND_OPT_NS_TARGETS, BOND_OPT_LAST }; @@ -140,5 +141,8 @@ static inline void __bond_opt_init(struct bond_opt_value *optval, __bond_opt_init(optval, NULL, ULLONG_MAX, extra, extra_len) void bond_option_arp_ip_targets_clear(struct bonding *bond); +#if IS_ENABLED(CONFIG_IPV6) +void bond_option_ns_ip6_targets_clear(struct bonding *bond); +#endif #endif /* _NET_BOND_OPTIONS_H */ diff --git a/include/net/bonding.h b/include/net/bonding.h index f3b986f6b6e4..d0dfe727e0b1 100644 --- a/include/net/bonding.h +++ b/include/net/bonding.h @@ -503,6 +503,13 @@ static inline int bond_is_ip_target_ok(__be32 addr) return !ipv4_is_lbcast(addr) && !ipv4_is_zeronet(addr); } +static inline int bond_is_ip6_target_ok(struct in6_addr *addr) +{ + return !ipv6_addr_any(addr) && + !ipv6_addr_loopback(addr) && + !ipv6_addr_is_multicast(addr); +} + /* Get the oldest arp which we've received on this slave for bond's * arp_targets. */ diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h index 6218f93f5c1a..e1ba2d51b717 100644 --- a/include/uapi/linux/if_link.h +++ b/include/uapi/linux/if_link.h @@ -860,6 +860,7 @@ enum { IFLA_BOND_PEER_NOTIF_DELAY, IFLA_BOND_AD_LACP_ACTIVE, IFLA_BOND_MISSED_MAX, + IFLA_BOND_NS_IP6_TARGET, __IFLA_BOND_MAX, }; diff --git a/tools/include/uapi/linux/if_link.h b/tools/include/uapi/linux/if_link.h index 6218f93f5c1a..e1ba2d51b717 100644 --- a/tools/include/uapi/linux/if_link.h +++ b/tools/include/uapi/linux/if_link.h @@ -860,6 +860,7 @@ enum { IFLA_BOND_PEER_NOTIF_DELAY, IFLA_BOND_AD_LACP_ACTIVE, IFLA_BOND_MISSED_MAX, + IFLA_BOND_NS_IP6_TARGET, __IFLA_BOND_MAX, }; -- cgit v1.2.3 From 8d21ec0e46ed6e39994accff8eb4f2be3d2e76b5 Mon Sep 17 00:00:00 2001 From: Martin KaFai Lau Date: Wed, 2 Mar 2022 11:56:34 -0800 Subject: bpf: Add __sk_buff->delivery_time_type and bpf_skb_set_skb_delivery_time() * __sk_buff->delivery_time_type: This patch adds __sk_buff->delivery_time_type. It tells if the delivery_time is stored in __sk_buff->tstamp or not. It will be most useful for ingress to tell if the __sk_buff->tstamp has the (rcv) timestamp or delivery_time. If delivery_time_type is 0 (BPF_SKB_DELIVERY_TIME_NONE), it has the (rcv) timestamp. Two non-zero types are defined for the delivery_time_type, BPF_SKB_DELIVERY_TIME_MONO and BPF_SKB_DELIVERY_TIME_UNSPEC. For UNSPEC, it can only happen in egress because only mono delivery_time can be forwarded to ingress now. The clock of UNSPEC delivery_time can be deduced from the skb->sk->sk_clockid which is how the sch_etf doing it also. * Provide forwarded delivery_time to tc-bpf@ingress: With the help of the new delivery_time_type, the tc-bpf has a way to tell if the __sk_buff->tstamp has the (rcv) timestamp or the delivery_time. During bpf load time, the verifier will learn if the bpf prog has accessed the new __sk_buff->delivery_time_type. If it does, it means the tc-bpf@ingress is expecting the skb->tstamp could have the delivery_time. The kernel will then read the skb->tstamp as-is during bpf insn rewrite without checking the skb->mono_delivery_time. This is done by adding a new prog->delivery_time_access bit. The same goes for writing skb->tstamp. * bpf_skb_set_delivery_time(): The bpf_skb_set_delivery_time() helper is added to allow setting both delivery_time and the delivery_time_type at the same time. If the tc-bpf does not need to change the delivery_time_type, it can directly write to the __sk_buff->tstamp as the existing tc-bpf has already been doing. It will be most useful at ingress to change the __sk_buff->tstamp from the (rcv) timestamp to a mono delivery_time and then bpf_redirect_*(). bpf only has mono clock helper (bpf_ktime_get_ns), and the current known use case is the mono EDT for fq, and only mono delivery time can be kept during forward now, so bpf_skb_set_delivery_time() only supports setting BPF_SKB_DELIVERY_TIME_MONO. It can be extended later when use cases come up and the forwarding path also supports other clock bases. Signed-off-by: Martin KaFai Lau Signed-off-by: David S. Miller --- include/linux/filter.h | 3 +- include/uapi/linux/bpf.h | 41 +++++++++- net/core/filter.c | 169 ++++++++++++++++++++++++++++++++--------- tools/include/uapi/linux/bpf.h | 41 +++++++++- 4 files changed, 216 insertions(+), 38 deletions(-) (limited to 'tools/include/uapi') diff --git a/include/linux/filter.h b/include/linux/filter.h index 1cb1af917617..9bf26307247f 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -572,7 +572,8 @@ struct bpf_prog { has_callchain_buf:1, /* callchain buffer allocated? */ enforce_expected_attach_type:1, /* Enforce expected_attach_type checking at attach time */ call_get_stack:1, /* Do we call bpf_get_stack() or bpf_get_stackid() */ - call_get_func_ip:1; /* Do we call get_func_ip() */ + call_get_func_ip:1, /* Do we call get_func_ip() */ + delivery_time_access:1; /* Accessed __sk_buff->delivery_time_type */ enum bpf_prog_type type; /* Type of BPF program */ enum bpf_attach_type expected_attach_type; /* For some prog types */ u32 len; /* Number of filter blocks */ diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index afe3d0d7f5f2..4eebea830613 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -5086,6 +5086,37 @@ union bpf_attr { * Return * 0 on success, or a negative error in case of failure. On error * *dst* buffer is zeroed out. + * + * long bpf_skb_set_delivery_time(struct sk_buff *skb, u64 dtime, u32 dtime_type) + * Description + * Set a *dtime* (delivery time) to the __sk_buff->tstamp and also + * change the __sk_buff->delivery_time_type to *dtime_type*. + * + * When setting a delivery time (non zero *dtime*) to + * __sk_buff->tstamp, only BPF_SKB_DELIVERY_TIME_MONO *dtime_type* + * is supported. It is the only delivery_time_type that will be + * kept after bpf_redirect_*(). + * + * If there is no need to change the __sk_buff->delivery_time_type, + * the delivery time can be directly written to __sk_buff->tstamp + * instead. + * + * *dtime* 0 and *dtime_type* BPF_SKB_DELIVERY_TIME_NONE + * can be used to clear any delivery time stored in + * __sk_buff->tstamp. + * + * Only IPv4 and IPv6 skb->protocol are supported. + * + * This function is most useful when it needs to set a + * mono delivery time to __sk_buff->tstamp and then + * bpf_redirect_*() to the egress of an iface. For example, + * changing the (rcv) timestamp in __sk_buff->tstamp at + * ingress to a mono delivery time and then bpf_redirect_*() + * to sch_fq@phy-dev. + * Return + * 0 on success. + * **-EINVAL** for invalid input + * **-EOPNOTSUPP** for unsupported delivery_time_type and protocol */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -5280,6 +5311,7 @@ union bpf_attr { FN(xdp_load_bytes), \ FN(xdp_store_bytes), \ FN(copy_from_user_task), \ + FN(skb_set_delivery_time), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper @@ -5469,6 +5501,12 @@ union { \ __u64 :64; \ } __attribute__((aligned(8))) +enum { + BPF_SKB_DELIVERY_TIME_NONE, + BPF_SKB_DELIVERY_TIME_UNSPEC, + BPF_SKB_DELIVERY_TIME_MONO, +}; + /* user accessible mirror of in-kernel sk_buff. * new fields can only be added to the end of this structure */ @@ -5509,7 +5547,8 @@ struct __sk_buff { __u32 gso_segs; __bpf_md_ptr(struct bpf_sock *, sk); __u32 gso_size; - __u32 :32; /* Padding, future use. */ + __u8 delivery_time_type; + __u32 :24; /* Padding, future use. */ __u64 hwtstamp; }; diff --git a/net/core/filter.c b/net/core/filter.c index 5072733743e9..88767f7da150 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -7388,6 +7388,43 @@ static const struct bpf_func_proto bpf_sock_ops_reserve_hdr_opt_proto = { .arg3_type = ARG_ANYTHING, }; +BPF_CALL_3(bpf_skb_set_delivery_time, struct sk_buff *, skb, + u64, dtime, u32, dtime_type) +{ + /* skb_clear_delivery_time() is done for inet protocol */ + if (skb->protocol != htons(ETH_P_IP) && + skb->protocol != htons(ETH_P_IPV6)) + return -EOPNOTSUPP; + + switch (dtime_type) { + case BPF_SKB_DELIVERY_TIME_MONO: + if (!dtime) + return -EINVAL; + skb->tstamp = dtime; + skb->mono_delivery_time = 1; + break; + case BPF_SKB_DELIVERY_TIME_NONE: + if (dtime) + return -EINVAL; + skb->tstamp = 0; + skb->mono_delivery_time = 0; + break; + default: + return -EOPNOTSUPP; + } + + return 0; +} + +static const struct bpf_func_proto bpf_skb_set_delivery_time_proto = { + .func = bpf_skb_set_delivery_time, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, + .arg2_type = ARG_ANYTHING, + .arg3_type = ARG_ANYTHING, +}; + #endif /* CONFIG_INET */ bool bpf_helper_changes_pkt_data(void *func) @@ -7749,6 +7786,8 @@ tc_cls_act_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_tcp_gen_syncookie_proto; case BPF_FUNC_sk_assign: return &bpf_sk_assign_proto; + case BPF_FUNC_skb_set_delivery_time: + return &bpf_skb_set_delivery_time_proto; #endif default: return bpf_sk_base_func_proto(func_id); @@ -8088,7 +8127,9 @@ static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type return false; info->reg_type = PTR_TO_SOCK_COMMON_OR_NULL; break; - case offsetofend(struct __sk_buff, gso_size) ... offsetof(struct __sk_buff, hwtstamp) - 1: + case offsetof(struct __sk_buff, delivery_time_type): + return false; + case offsetofend(struct __sk_buff, delivery_time_type) ... offsetof(struct __sk_buff, hwtstamp) - 1: /* Explicitly prohibit access to padding in __sk_buff. */ return false; default: @@ -8443,6 +8484,15 @@ static bool tc_cls_act_is_valid_access(int off, int size, break; case bpf_ctx_range_till(struct __sk_buff, family, local_port): return false; + case offsetof(struct __sk_buff, delivery_time_type): + /* The convert_ctx_access() on reading and writing + * __sk_buff->tstamp depends on whether the bpf prog + * has used __sk_buff->delivery_time_type or not. + * Thus, we need to set prog->delivery_time_access + * earlier during is_valid_access() here. + */ + ((struct bpf_prog *)prog)->delivery_time_access = 1; + return size == sizeof(__u8); } return bpf_skb_is_valid_access(off, size, type, prog, info); @@ -8838,6 +8888,45 @@ static u32 flow_dissector_convert_ctx_access(enum bpf_access_type type, return insn - insn_buf; } +static struct bpf_insn *bpf_convert_dtime_type_read(const struct bpf_insn *si, + struct bpf_insn *insn) +{ + __u8 value_reg = si->dst_reg; + __u8 skb_reg = si->src_reg; + __u8 tmp_reg = BPF_REG_AX; + + *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, + SKB_MONO_DELIVERY_TIME_OFFSET); + *insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, + SKB_MONO_DELIVERY_TIME_MASK); + *insn++ = BPF_JMP32_IMM(BPF_JEQ, tmp_reg, 0, 2); + /* value_reg = BPF_SKB_DELIVERY_TIME_MONO */ + *insn++ = BPF_MOV32_IMM(value_reg, BPF_SKB_DELIVERY_TIME_MONO); + *insn++ = BPF_JMP_A(IS_ENABLED(CONFIG_NET_CLS_ACT) ? 10 : 5); + + *insn++ = BPF_LDX_MEM(BPF_DW, tmp_reg, skb_reg, + offsetof(struct sk_buff, tstamp)); + *insn++ = BPF_JMP_IMM(BPF_JNE, tmp_reg, 0, 2); + /* value_reg = BPF_SKB_DELIVERY_TIME_NONE */ + *insn++ = BPF_MOV32_IMM(value_reg, BPF_SKB_DELIVERY_TIME_NONE); + *insn++ = BPF_JMP_A(IS_ENABLED(CONFIG_NET_CLS_ACT) ? 6 : 1); + +#ifdef CONFIG_NET_CLS_ACT + *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, TC_AT_INGRESS_OFFSET); + *insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, TC_AT_INGRESS_MASK); + *insn++ = BPF_JMP32_IMM(BPF_JEQ, tmp_reg, 0, 2); + /* At ingress, value_reg = 0 */ + *insn++ = BPF_MOV32_IMM(value_reg, 0); + *insn++ = BPF_JMP_A(1); +#endif + + /* value_reg = BPF_SKB_DELIVERYT_TIME_UNSPEC */ + *insn++ = BPF_MOV32_IMM(value_reg, BPF_SKB_DELIVERY_TIME_UNSPEC); + + /* 15 insns with CONFIG_NET_CLS_ACT */ + return insn; +} + static struct bpf_insn *bpf_convert_shinfo_access(const struct bpf_insn *si, struct bpf_insn *insn) { @@ -8859,29 +8948,32 @@ static struct bpf_insn *bpf_convert_shinfo_access(const struct bpf_insn *si, return insn; } -static struct bpf_insn *bpf_convert_tstamp_read(const struct bpf_insn *si, +static struct bpf_insn *bpf_convert_tstamp_read(const struct bpf_prog *prog, + const struct bpf_insn *si, struct bpf_insn *insn) { __u8 value_reg = si->dst_reg; __u8 skb_reg = si->src_reg; #ifdef CONFIG_NET_CLS_ACT - __u8 tmp_reg = BPF_REG_AX; - - *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, TC_AT_INGRESS_OFFSET); - *insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, TC_AT_INGRESS_MASK); - *insn++ = BPF_JMP32_IMM(BPF_JEQ, tmp_reg, 0, 5); - /* @ingress, read __sk_buff->tstamp as the (rcv) timestamp, - * so check the skb->mono_delivery_time. - */ - *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, - SKB_MONO_DELIVERY_TIME_OFFSET); - *insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, - SKB_MONO_DELIVERY_TIME_MASK); - *insn++ = BPF_JMP32_IMM(BPF_JEQ, tmp_reg, 0, 2); - /* skb->mono_delivery_time is set, read 0 as the (rcv) timestamp. */ - *insn++ = BPF_MOV64_IMM(value_reg, 0); - *insn++ = BPF_JMP_A(1); + if (!prog->delivery_time_access) { + __u8 tmp_reg = BPF_REG_AX; + + *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, TC_AT_INGRESS_OFFSET); + *insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, TC_AT_INGRESS_MASK); + *insn++ = BPF_JMP32_IMM(BPF_JEQ, tmp_reg, 0, 5); + /* @ingress, read __sk_buff->tstamp as the (rcv) timestamp, + * so check the skb->mono_delivery_time. + */ + *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, + SKB_MONO_DELIVERY_TIME_OFFSET); + *insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, + SKB_MONO_DELIVERY_TIME_MASK); + *insn++ = BPF_JMP32_IMM(BPF_JEQ, tmp_reg, 0, 2); + /* skb->mono_delivery_time is set, read 0 as the (rcv) timestamp. */ + *insn++ = BPF_MOV64_IMM(value_reg, 0); + *insn++ = BPF_JMP_A(1); + } #endif *insn++ = BPF_LDX_MEM(BPF_DW, value_reg, skb_reg, @@ -8889,27 +8981,30 @@ static struct bpf_insn *bpf_convert_tstamp_read(const struct bpf_insn *si, return insn; } -static struct bpf_insn *bpf_convert_tstamp_write(const struct bpf_insn *si, +static struct bpf_insn *bpf_convert_tstamp_write(const struct bpf_prog *prog, + const struct bpf_insn *si, struct bpf_insn *insn) { __u8 value_reg = si->src_reg; __u8 skb_reg = si->dst_reg; #ifdef CONFIG_NET_CLS_ACT - __u8 tmp_reg = BPF_REG_AX; - - *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, TC_AT_INGRESS_OFFSET); - *insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, TC_AT_INGRESS_MASK); - *insn++ = BPF_JMP32_IMM(BPF_JEQ, tmp_reg, 0, 3); - /* Writing __sk_buff->tstamp at ingress as the (rcv) timestamp. - * Clear the skb->mono_delivery_time. - */ - *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, - SKB_MONO_DELIVERY_TIME_OFFSET); - *insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, - ~SKB_MONO_DELIVERY_TIME_MASK); - *insn++ = BPF_STX_MEM(BPF_B, skb_reg, tmp_reg, - SKB_MONO_DELIVERY_TIME_OFFSET); + if (!prog->delivery_time_access) { + __u8 tmp_reg = BPF_REG_AX; + + *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, TC_AT_INGRESS_OFFSET); + *insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, TC_AT_INGRESS_MASK); + *insn++ = BPF_JMP32_IMM(BPF_JEQ, tmp_reg, 0, 3); + /* Writing __sk_buff->tstamp at ingress as the (rcv) timestamp. + * Clear the skb->mono_delivery_time. + */ + *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, + SKB_MONO_DELIVERY_TIME_OFFSET); + *insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, + ~SKB_MONO_DELIVERY_TIME_MASK); + *insn++ = BPF_STX_MEM(BPF_B, skb_reg, tmp_reg, + SKB_MONO_DELIVERY_TIME_OFFSET); + } #endif /* skb->tstamp = tstamp */ @@ -9226,9 +9321,13 @@ static u32 bpf_convert_ctx_access(enum bpf_access_type type, BUILD_BUG_ON(sizeof_field(struct sk_buff, tstamp) != 8); if (type == BPF_WRITE) - insn = bpf_convert_tstamp_write(si, insn); + insn = bpf_convert_tstamp_write(prog, si, insn); else - insn = bpf_convert_tstamp_read(si, insn); + insn = bpf_convert_tstamp_read(prog, si, insn); + break; + + case offsetof(struct __sk_buff, delivery_time_type): + insn = bpf_convert_dtime_type_read(si, insn); break; case offsetof(struct __sk_buff, gso_segs): diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index afe3d0d7f5f2..4eebea830613 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -5086,6 +5086,37 @@ union bpf_attr { * Return * 0 on success, or a negative error in case of failure. On error * *dst* buffer is zeroed out. + * + * long bpf_skb_set_delivery_time(struct sk_buff *skb, u64 dtime, u32 dtime_type) + * Description + * Set a *dtime* (delivery time) to the __sk_buff->tstamp and also + * change the __sk_buff->delivery_time_type to *dtime_type*. + * + * When setting a delivery time (non zero *dtime*) to + * __sk_buff->tstamp, only BPF_SKB_DELIVERY_TIME_MONO *dtime_type* + * is supported. It is the only delivery_time_type that will be + * kept after bpf_redirect_*(). + * + * If there is no need to change the __sk_buff->delivery_time_type, + * the delivery time can be directly written to __sk_buff->tstamp + * instead. + * + * *dtime* 0 and *dtime_type* BPF_SKB_DELIVERY_TIME_NONE + * can be used to clear any delivery time stored in + * __sk_buff->tstamp. + * + * Only IPv4 and IPv6 skb->protocol are supported. + * + * This function is most useful when it needs to set a + * mono delivery time to __sk_buff->tstamp and then + * bpf_redirect_*() to the egress of an iface. For example, + * changing the (rcv) timestamp in __sk_buff->tstamp at + * ingress to a mono delivery time and then bpf_redirect_*() + * to sch_fq@phy-dev. + * Return + * 0 on success. + * **-EINVAL** for invalid input + * **-EOPNOTSUPP** for unsupported delivery_time_type and protocol */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -5280,6 +5311,7 @@ union bpf_attr { FN(xdp_load_bytes), \ FN(xdp_store_bytes), \ FN(copy_from_user_task), \ + FN(skb_set_delivery_time), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper @@ -5469,6 +5501,12 @@ union { \ __u64 :64; \ } __attribute__((aligned(8))) +enum { + BPF_SKB_DELIVERY_TIME_NONE, + BPF_SKB_DELIVERY_TIME_UNSPEC, + BPF_SKB_DELIVERY_TIME_MONO, +}; + /* user accessible mirror of in-kernel sk_buff. * new fields can only be added to the end of this structure */ @@ -5509,7 +5547,8 @@ struct __sk_buff { __u32 gso_segs; __bpf_md_ptr(struct bpf_sock *, sk); __u32 gso_size; - __u32 :32; /* Padding, future use. */ + __u8 delivery_time_type; + __u32 :24; /* Padding, future use. */ __u64 hwtstamp; }; -- cgit v1.2.3 From b530e9e1063ed2b817eae7eec6ed2daa8be11608 Mon Sep 17 00:00:00 2001 From: Toke Høiland-Jørgensen Date: Wed, 9 Mar 2022 11:53:42 +0100 Subject: bpf: Add "live packet" mode for XDP in BPF_PROG_RUN MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This adds support for running XDP programs through BPF_PROG_RUN in a mode that enables live packet processing of the resulting frames. Previous uses of BPF_PROG_RUN for XDP returned the XDP program return code and the modified packet data to userspace, which is useful for unit testing of XDP programs. The existing BPF_PROG_RUN for XDP allows userspace to set the ingress ifindex and RXQ number as part of the context object being passed to the kernel. This patch reuses that code, but adds a new mode with different semantics, which can be selected with the new BPF_F_TEST_XDP_LIVE_FRAMES flag. When running BPF_PROG_RUN in this mode, the XDP program return codes will be honoured: returning XDP_PASS will result in the frame being injected into the networking stack as if it came from the selected networking interface, while returning XDP_TX and XDP_REDIRECT will result in the frame being transmitted out that interface. XDP_TX is translated into an XDP_REDIRECT operation to the same interface, since the real XDP_TX action is only possible from within the network drivers themselves, not from the process context where BPF_PROG_RUN is executed. Internally, this new mode of operation creates a page pool instance while setting up the test run, and feeds pages from that into the XDP program. The setup cost of this is amortised over the number of repetitions specified by userspace. To support the performance testing use case, we further optimise the setup step so that all pages in the pool are pre-initialised with the packet data, and pre-computed context and xdp_frame objects stored at the start of each page. This makes it possible to entirely avoid touching the page content on each XDP program invocation, and enables sending up to 9 Mpps/core on my test box. Because the data pages are recycled by the page pool, and the test runner doesn't re-initialise them for each run, subsequent invocations of the XDP program will see the packet data in the state it was after the last time it ran on that particular page. This means that an XDP program that modifies the packet before redirecting it has to be careful about which assumptions it makes about the packet content, but that is only an issue for the most naively written programs. Enabling the new flag is only allowed when not setting ctx_out and data_out in the test specification, since using it means frames will be redirected somewhere else, so they can't be returned. Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Alexei Starovoitov Acked-by: Martin KaFai Lau Link: https://lore.kernel.org/bpf/20220309105346.100053-2-toke@redhat.com --- include/uapi/linux/bpf.h | 3 + kernel/bpf/Kconfig | 1 + kernel/bpf/syscall.c | 2 +- net/bpf/test_run.c | 334 +++++++++++++++++++++++++++++++++++++++-- tools/include/uapi/linux/bpf.h | 3 + 5 files changed, 328 insertions(+), 15 deletions(-) (limited to 'tools/include/uapi') diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 4eebea830613..bc23020b638d 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -1232,6 +1232,8 @@ enum { /* If set, run the test on the cpu specified by bpf_attr.test.cpu */ #define BPF_F_TEST_RUN_ON_CPU (1U << 0) +/* If set, XDP frames will be transmitted after processing */ +#define BPF_F_TEST_XDP_LIVE_FRAMES (1U << 1) /* type for BPF_ENABLE_STATS */ enum bpf_stats_type { @@ -1393,6 +1395,7 @@ union bpf_attr { __aligned_u64 ctx_out; __u32 flags; __u32 cpu; + __u32 batch_size; } test; struct { /* anonymous struct used by BPF_*_GET_*_ID */ diff --git a/kernel/bpf/Kconfig b/kernel/bpf/Kconfig index c3cf0b86eeb2..d56ee177d5f8 100644 --- a/kernel/bpf/Kconfig +++ b/kernel/bpf/Kconfig @@ -30,6 +30,7 @@ config BPF_SYSCALL select TASKS_TRACE_RCU select BINARY_PRINTF select NET_SOCK_MSG if NET + select PAGE_POOL if NET default n help Enable the bpf() system call that allows to manipulate BPF programs diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index db402ebc5570..9beb585be5a6 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -3336,7 +3336,7 @@ static int bpf_prog_query(const union bpf_attr *attr, } } -#define BPF_PROG_TEST_RUN_LAST_FIELD test.cpu +#define BPF_PROG_TEST_RUN_LAST_FIELD test.batch_size static int bpf_prog_test_run(const union bpf_attr *attr, union bpf_attr __user *uattr) diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c index ba410b069824..25169908be4a 100644 --- a/net/bpf/test_run.c +++ b/net/bpf/test_run.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include #include @@ -53,10 +54,11 @@ static void bpf_test_timer_leave(struct bpf_test_timer *t) rcu_read_unlock(); } -static bool bpf_test_timer_continue(struct bpf_test_timer *t, u32 repeat, int *err, u32 *duration) +static bool bpf_test_timer_continue(struct bpf_test_timer *t, int iterations, + u32 repeat, int *err, u32 *duration) __must_hold(rcu) { - t->i++; + t->i += iterations; if (t->i >= repeat) { /* We're done. */ t->time_spent += ktime_get_ns() - t->time_start; @@ -88,6 +90,286 @@ reset: return false; } +/* We put this struct at the head of each page with a context and frame + * initialised when the page is allocated, so we don't have to do this on each + * repetition of the test run. + */ +struct xdp_page_head { + struct xdp_buff orig_ctx; + struct xdp_buff ctx; + struct xdp_frame frm; + u8 data[]; +}; + +struct xdp_test_data { + struct xdp_buff *orig_ctx; + struct xdp_rxq_info rxq; + struct net_device *dev; + struct page_pool *pp; + struct xdp_frame **frames; + struct sk_buff **skbs; + u32 batch_size; + u32 frame_cnt; +}; + +#define TEST_XDP_FRAME_SIZE (PAGE_SIZE - sizeof(struct xdp_page_head) \ + - sizeof(struct skb_shared_info)) +#define TEST_XDP_MAX_BATCH 256 + +static void xdp_test_run_init_page(struct page *page, void *arg) +{ + struct xdp_page_head *head = phys_to_virt(page_to_phys(page)); + struct xdp_buff *new_ctx, *orig_ctx; + u32 headroom = XDP_PACKET_HEADROOM; + struct xdp_test_data *xdp = arg; + size_t frm_len, meta_len; + struct xdp_frame *frm; + void *data; + + orig_ctx = xdp->orig_ctx; + frm_len = orig_ctx->data_end - orig_ctx->data_meta; + meta_len = orig_ctx->data - orig_ctx->data_meta; + headroom -= meta_len; + + new_ctx = &head->ctx; + frm = &head->frm; + data = &head->data; + memcpy(data + headroom, orig_ctx->data_meta, frm_len); + + xdp_init_buff(new_ctx, TEST_XDP_FRAME_SIZE, &xdp->rxq); + xdp_prepare_buff(new_ctx, data, headroom, frm_len, true); + new_ctx->data = new_ctx->data_meta + meta_len; + + xdp_update_frame_from_buff(new_ctx, frm); + frm->mem = new_ctx->rxq->mem; + + memcpy(&head->orig_ctx, new_ctx, sizeof(head->orig_ctx)); +} + +static int xdp_test_run_setup(struct xdp_test_data *xdp, struct xdp_buff *orig_ctx) +{ + struct xdp_mem_info mem = {}; + struct page_pool *pp; + int err = -ENOMEM; + struct page_pool_params pp_params = { + .order = 0, + .flags = 0, + .pool_size = xdp->batch_size, + .nid = NUMA_NO_NODE, + .max_len = TEST_XDP_FRAME_SIZE, + .init_callback = xdp_test_run_init_page, + .init_arg = xdp, + }; + + xdp->frames = kvmalloc_array(xdp->batch_size, sizeof(void *), GFP_KERNEL); + if (!xdp->frames) + return -ENOMEM; + + xdp->skbs = kvmalloc_array(xdp->batch_size, sizeof(void *), GFP_KERNEL); + if (!xdp->skbs) + goto err_skbs; + + pp = page_pool_create(&pp_params); + if (IS_ERR(pp)) { + err = PTR_ERR(pp); + goto err_pp; + } + + /* will copy 'mem.id' into pp->xdp_mem_id */ + err = xdp_reg_mem_model(&mem, MEM_TYPE_PAGE_POOL, pp); + if (err) + goto err_mmodel; + + xdp->pp = pp; + + /* We create a 'fake' RXQ referencing the original dev, but with an + * xdp_mem_info pointing to our page_pool + */ + xdp_rxq_info_reg(&xdp->rxq, orig_ctx->rxq->dev, 0, 0); + xdp->rxq.mem.type = MEM_TYPE_PAGE_POOL; + xdp->rxq.mem.id = pp->xdp_mem_id; + xdp->dev = orig_ctx->rxq->dev; + xdp->orig_ctx = orig_ctx; + + return 0; + +err_mmodel: + page_pool_destroy(pp); +err_pp: + kfree(xdp->skbs); +err_skbs: + kfree(xdp->frames); + return err; +} + +static void xdp_test_run_teardown(struct xdp_test_data *xdp) +{ + page_pool_destroy(xdp->pp); + kfree(xdp->frames); + kfree(xdp->skbs); +} + +static bool ctx_was_changed(struct xdp_page_head *head) +{ + return head->orig_ctx.data != head->ctx.data || + head->orig_ctx.data_meta != head->ctx.data_meta || + head->orig_ctx.data_end != head->ctx.data_end; +} + +static void reset_ctx(struct xdp_page_head *head) +{ + if (likely(!ctx_was_changed(head))) + return; + + head->ctx.data = head->orig_ctx.data; + head->ctx.data_meta = head->orig_ctx.data_meta; + head->ctx.data_end = head->orig_ctx.data_end; + xdp_update_frame_from_buff(&head->ctx, &head->frm); +} + +static int xdp_recv_frames(struct xdp_frame **frames, int nframes, + struct sk_buff **skbs, + struct net_device *dev) +{ + gfp_t gfp = __GFP_ZERO | GFP_ATOMIC; + int i, n; + LIST_HEAD(list); + + n = kmem_cache_alloc_bulk(skbuff_head_cache, gfp, nframes, (void **)skbs); + if (unlikely(n == 0)) { + for (i = 0; i < nframes; i++) + xdp_return_frame(frames[i]); + return -ENOMEM; + } + + for (i = 0; i < nframes; i++) { + struct xdp_frame *xdpf = frames[i]; + struct sk_buff *skb = skbs[i]; + + skb = __xdp_build_skb_from_frame(xdpf, skb, dev); + if (!skb) { + xdp_return_frame(xdpf); + continue; + } + + list_add_tail(&skb->list, &list); + } + netif_receive_skb_list(&list); + + return 0; +} + +static int xdp_test_run_batch(struct xdp_test_data *xdp, struct bpf_prog *prog, + u32 repeat) +{ + struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); + int err = 0, act, ret, i, nframes = 0, batch_sz; + struct xdp_frame **frames = xdp->frames; + struct xdp_page_head *head; + struct xdp_frame *frm; + bool redirect = false; + struct xdp_buff *ctx; + struct page *page; + + batch_sz = min_t(u32, repeat, xdp->batch_size); + + local_bh_disable(); + xdp_set_return_frame_no_direct(); + + for (i = 0; i < batch_sz; i++) { + page = page_pool_dev_alloc_pages(xdp->pp); + if (!page) { + err = -ENOMEM; + goto out; + } + + head = phys_to_virt(page_to_phys(page)); + reset_ctx(head); + ctx = &head->ctx; + frm = &head->frm; + xdp->frame_cnt++; + + act = bpf_prog_run_xdp(prog, ctx); + + /* if program changed pkt bounds we need to update the xdp_frame */ + if (unlikely(ctx_was_changed(head))) { + ret = xdp_update_frame_from_buff(ctx, frm); + if (ret) { + xdp_return_buff(ctx); + continue; + } + } + + switch (act) { + case XDP_TX: + /* we can't do a real XDP_TX since we're not in the + * driver, so turn it into a REDIRECT back to the same + * index + */ + ri->tgt_index = xdp->dev->ifindex; + ri->map_id = INT_MAX; + ri->map_type = BPF_MAP_TYPE_UNSPEC; + fallthrough; + case XDP_REDIRECT: + redirect = true; + ret = xdp_do_redirect_frame(xdp->dev, ctx, frm, prog); + if (ret) + xdp_return_buff(ctx); + break; + case XDP_PASS: + frames[nframes++] = frm; + break; + default: + bpf_warn_invalid_xdp_action(NULL, prog, act); + fallthrough; + case XDP_DROP: + xdp_return_buff(ctx); + break; + } + } + +out: + if (redirect) + xdp_do_flush(); + if (nframes) { + ret = xdp_recv_frames(frames, nframes, xdp->skbs, xdp->dev); + if (ret) + err = ret; + } + + xdp_clear_return_frame_no_direct(); + local_bh_enable(); + return err; +} + +static int bpf_test_run_xdp_live(struct bpf_prog *prog, struct xdp_buff *ctx, + u32 repeat, u32 batch_size, u32 *time) + +{ + struct xdp_test_data xdp = { .batch_size = batch_size }; + struct bpf_test_timer t = { .mode = NO_MIGRATE }; + int ret; + + if (!repeat) + repeat = 1; + + ret = xdp_test_run_setup(&xdp, ctx); + if (ret) + return ret; + + bpf_test_timer_enter(&t); + do { + xdp.frame_cnt = 0; + ret = xdp_test_run_batch(&xdp, prog, repeat - t.i); + if (unlikely(ret < 0)) + break; + } while (bpf_test_timer_continue(&t, xdp.frame_cnt, repeat, &ret, time)); + bpf_test_timer_leave(&t); + + xdp_test_run_teardown(&xdp); + return ret; +} + static int bpf_test_run(struct bpf_prog *prog, void *ctx, u32 repeat, u32 *retval, u32 *time, bool xdp) { @@ -119,7 +401,7 @@ static int bpf_test_run(struct bpf_prog *prog, void *ctx, u32 repeat, *retval = bpf_prog_run_xdp(prog, ctx); else *retval = bpf_prog_run(prog, ctx); - } while (bpf_test_timer_continue(&t, repeat, &ret, time)); + } while (bpf_test_timer_continue(&t, 1, repeat, &ret, time)); bpf_reset_run_ctx(old_ctx); bpf_test_timer_leave(&t); @@ -446,7 +728,7 @@ int bpf_prog_test_run_tracing(struct bpf_prog *prog, int b = 2, err = -EFAULT; u32 retval = 0; - if (kattr->test.flags || kattr->test.cpu) + if (kattr->test.flags || kattr->test.cpu || kattr->test.batch_size) return -EINVAL; switch (prog->expected_attach_type) { @@ -510,7 +792,7 @@ int bpf_prog_test_run_raw_tp(struct bpf_prog *prog, /* doesn't support data_in/out, ctx_out, duration, or repeat */ if (kattr->test.data_in || kattr->test.data_out || kattr->test.ctx_out || kattr->test.duration || - kattr->test.repeat) + kattr->test.repeat || kattr->test.batch_size) return -EINVAL; if (ctx_size_in < prog->aux->max_ctx_offset || @@ -741,7 +1023,7 @@ int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr, void *data; int ret; - if (kattr->test.flags || kattr->test.cpu) + if (kattr->test.flags || kattr->test.cpu || kattr->test.batch_size) return -EINVAL; data = bpf_test_init(kattr, kattr->test.data_size_in, @@ -922,7 +1204,9 @@ static void xdp_convert_buff_to_md(struct xdp_buff *xdp, struct xdp_md *xdp_md) int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr, union bpf_attr __user *uattr) { + bool do_live = (kattr->test.flags & BPF_F_TEST_XDP_LIVE_FRAMES); u32 tailroom = SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); + u32 batch_size = kattr->test.batch_size; u32 size = kattr->test.data_size_in; u32 headroom = XDP_PACKET_HEADROOM; u32 retval, duration, max_data_sz; @@ -938,6 +1222,18 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr, prog->expected_attach_type == BPF_XDP_CPUMAP) return -EINVAL; + if (kattr->test.flags & ~BPF_F_TEST_XDP_LIVE_FRAMES) + return -EINVAL; + + if (do_live) { + if (!batch_size) + batch_size = NAPI_POLL_WEIGHT; + else if (batch_size > TEST_XDP_MAX_BATCH) + return -E2BIG; + } else if (batch_size) { + return -EINVAL; + } + ctx = bpf_ctx_init(kattr, sizeof(struct xdp_md)); if (IS_ERR(ctx)) return PTR_ERR(ctx); @@ -946,14 +1242,20 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr, /* There can't be user provided data before the meta data */ if (ctx->data_meta || ctx->data_end != size || ctx->data > ctx->data_end || - unlikely(xdp_metalen_invalid(ctx->data))) + unlikely(xdp_metalen_invalid(ctx->data)) || + (do_live && (kattr->test.data_out || kattr->test.ctx_out))) goto free_ctx; /* Meta data is allocated from the headroom */ headroom -= ctx->data; } max_data_sz = 4096 - headroom - tailroom; - size = min_t(u32, size, max_data_sz); + if (size > max_data_sz) { + /* disallow live data mode for jumbo frames */ + if (do_live) + goto free_ctx; + size = max_data_sz; + } data = bpf_test_init(kattr, size, max_data_sz, headroom, tailroom); if (IS_ERR(data)) { @@ -1011,7 +1313,10 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr, if (repeat > 1) bpf_prog_change_xdp(NULL, prog); - ret = bpf_test_run(prog, &xdp, repeat, &retval, &duration, true); + if (do_live) + ret = bpf_test_run_xdp_live(prog, &xdp, repeat, batch_size, &duration); + else + ret = bpf_test_run(prog, &xdp, repeat, &retval, &duration, true); /* We convert the xdp_buff back to an xdp_md before checking the return * code so the reference count of any held netdevice will be decremented * even if the test run failed. @@ -1073,7 +1378,7 @@ int bpf_prog_test_run_flow_dissector(struct bpf_prog *prog, if (prog->type != BPF_PROG_TYPE_FLOW_DISSECTOR) return -EINVAL; - if (kattr->test.flags || kattr->test.cpu) + if (kattr->test.flags || kattr->test.cpu || kattr->test.batch_size) return -EINVAL; if (size < ETH_HLEN) @@ -1108,7 +1413,7 @@ int bpf_prog_test_run_flow_dissector(struct bpf_prog *prog, do { retval = bpf_flow_dissect(prog, &ctx, eth->h_proto, ETH_HLEN, size, flags); - } while (bpf_test_timer_continue(&t, repeat, &ret, &duration)); + } while (bpf_test_timer_continue(&t, 1, repeat, &ret, &duration)); bpf_test_timer_leave(&t); if (ret < 0) @@ -1140,7 +1445,7 @@ int bpf_prog_test_run_sk_lookup(struct bpf_prog *prog, const union bpf_attr *kat if (prog->type != BPF_PROG_TYPE_SK_LOOKUP) return -EINVAL; - if (kattr->test.flags || kattr->test.cpu) + if (kattr->test.flags || kattr->test.cpu || kattr->test.batch_size) return -EINVAL; if (kattr->test.data_in || kattr->test.data_size_in || kattr->test.data_out || @@ -1203,7 +1508,7 @@ int bpf_prog_test_run_sk_lookup(struct bpf_prog *prog, const union bpf_attr *kat do { ctx.selected_sk = NULL; retval = BPF_PROG_SK_LOOKUP_RUN_ARRAY(progs, ctx, bpf_prog_run); - } while (bpf_test_timer_continue(&t, repeat, &ret, &duration)); + } while (bpf_test_timer_continue(&t, 1, repeat, &ret, &duration)); bpf_test_timer_leave(&t); if (ret < 0) @@ -1242,7 +1547,8 @@ int bpf_prog_test_run_syscall(struct bpf_prog *prog, /* doesn't support data_in/out, ctx_out, duration, or repeat or flags */ if (kattr->test.data_in || kattr->test.data_out || kattr->test.ctx_out || kattr->test.duration || - kattr->test.repeat || kattr->test.flags) + kattr->test.repeat || kattr->test.flags || + kattr->test.batch_size) return -EINVAL; if (ctx_size_in < prog->aux->max_ctx_offset || diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 4eebea830613..bc23020b638d 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -1232,6 +1232,8 @@ enum { /* If set, run the test on the cpu specified by bpf_attr.test.cpu */ #define BPF_F_TEST_RUN_ON_CPU (1U << 0) +/* If set, XDP frames will be transmitted after processing */ +#define BPF_F_TEST_XDP_LIVE_FRAMES (1U << 1) /* type for BPF_ENABLE_STATS */ enum bpf_stats_type { @@ -1393,6 +1395,7 @@ union bpf_attr { __aligned_u64 ctx_out; __u32 flags; __u32 cpu; + __u32 batch_size; } test; struct { /* anonymous struct used by BPF_*_GET_*_ID */ -- cgit v1.2.3 From 9bb984f28d5bcb917d35d930fcfb89f90f9449fd Mon Sep 17 00:00:00 2001 From: Martin KaFai Lau Date: Wed, 9 Mar 2022 01:05:09 -0800 Subject: bpf: Remove BPF_SKB_DELIVERY_TIME_NONE and rename s/delivery_time_/tstamp_/ This patch is to simplify the uapi bpf.h regarding to the tstamp type and use a similar way as the kernel to describe the value stored in __sk_buff->tstamp. My earlier thought was to avoid describing the semantic and clock base for the rcv timestamp until there is more clarity on the use case, so the __sk_buff->delivery_time_type naming instead of __sk_buff->tstamp_type. With some thoughts, it can reuse the UNSPEC naming. This patch first removes BPF_SKB_DELIVERY_TIME_NONE and also rename BPF_SKB_DELIVERY_TIME_UNSPEC to BPF_SKB_TSTAMP_UNSPEC and BPF_SKB_DELIVERY_TIME_MONO to BPF_SKB_TSTAMP_DELIVERY_MONO. The semantic of BPF_SKB_TSTAMP_DELIVERY_MONO is the same: __sk_buff->tstamp has delivery time in mono clock base. BPF_SKB_TSTAMP_UNSPEC means __sk_buff->tstamp has the (rcv) tstamp at ingress and the delivery time at egress. At egress, the clock base could be found from skb->sk->sk_clockid. __sk_buff->tstamp == 0 naturally means NONE, so NONE is not needed. With BPF_SKB_TSTAMP_UNSPEC for the rcv tstamp at ingress, the __sk_buff->delivery_time_type is also renamed to __sk_buff->tstamp_type which was also suggested in the earlier discussion: https://lore.kernel.org/bpf/b181acbe-caf8-502d-4b7b-7d96b9fc5d55@iogearbox.net/ The above will then make __sk_buff->tstamp and __sk_buff->tstamp_type the same as its kernel skb->tstamp and skb->mono_delivery_time counter part. The internal kernel function bpf_skb_convert_dtime_type_read() is then renamed to bpf_skb_convert_tstamp_type_read() and it can be simplified with the BPF_SKB_DELIVERY_TIME_NONE gone. A BPF_ALU32_IMM(BPF_AND) insn is also saved by using BPF_JMP32_IMM(BPF_JSET). The bpf helper bpf_skb_set_delivery_time() is also renamed to bpf_skb_set_tstamp(). The arg name is changed from dtime to tstamp also. It only allows setting tstamp 0 for BPF_SKB_TSTAMP_UNSPEC and it could be relaxed later if there is use case to change mono delivery time to non mono. prog->delivery_time_access is also renamed to prog->tstamp_type_access. Signed-off-by: Martin KaFai Lau Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20220309090509.3712315-1-kafai@fb.com --- include/linux/filter.h | 2 +- include/uapi/linux/bpf.h | 40 ++++++++++--------- net/core/filter.c | 88 ++++++++++++++++-------------------------- tools/include/uapi/linux/bpf.h | 40 ++++++++++--------- 4 files changed, 77 insertions(+), 93 deletions(-) (limited to 'tools/include/uapi') diff --git a/include/linux/filter.h b/include/linux/filter.h index 9bf26307247f..05ed9bd31b45 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -573,7 +573,7 @@ struct bpf_prog { enforce_expected_attach_type:1, /* Enforce expected_attach_type checking at attach time */ call_get_stack:1, /* Do we call bpf_get_stack() or bpf_get_stackid() */ call_get_func_ip:1, /* Do we call get_func_ip() */ - delivery_time_access:1; /* Accessed __sk_buff->delivery_time_type */ + tstamp_type_access:1; /* Accessed __sk_buff->tstamp_type */ enum bpf_prog_type type; /* Type of BPF program */ enum bpf_attach_type expected_attach_type; /* For some prog types */ u32 len; /* Number of filter blocks */ diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index bc23020b638d..d288a0a9f797 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -5090,23 +5090,22 @@ union bpf_attr { * 0 on success, or a negative error in case of failure. On error * *dst* buffer is zeroed out. * - * long bpf_skb_set_delivery_time(struct sk_buff *skb, u64 dtime, u32 dtime_type) + * long bpf_skb_set_tstamp(struct sk_buff *skb, u64 tstamp, u32 tstamp_type) * Description - * Set a *dtime* (delivery time) to the __sk_buff->tstamp and also - * change the __sk_buff->delivery_time_type to *dtime_type*. + * Change the __sk_buff->tstamp_type to *tstamp_type* + * and set *tstamp* to the __sk_buff->tstamp together. * - * When setting a delivery time (non zero *dtime*) to - * __sk_buff->tstamp, only BPF_SKB_DELIVERY_TIME_MONO *dtime_type* - * is supported. It is the only delivery_time_type that will be - * kept after bpf_redirect_*(). - * - * If there is no need to change the __sk_buff->delivery_time_type, - * the delivery time can be directly written to __sk_buff->tstamp + * If there is no need to change the __sk_buff->tstamp_type, + * the tstamp value can be directly written to __sk_buff->tstamp * instead. * - * *dtime* 0 and *dtime_type* BPF_SKB_DELIVERY_TIME_NONE - * can be used to clear any delivery time stored in - * __sk_buff->tstamp. + * BPF_SKB_TSTAMP_DELIVERY_MONO is the only tstamp that + * will be kept during bpf_redirect_*(). A non zero + * *tstamp* must be used with the BPF_SKB_TSTAMP_DELIVERY_MONO + * *tstamp_type*. + * + * A BPF_SKB_TSTAMP_UNSPEC *tstamp_type* can only be used + * with a zero *tstamp*. * * Only IPv4 and IPv6 skb->protocol are supported. * @@ -5119,7 +5118,7 @@ union bpf_attr { * Return * 0 on success. * **-EINVAL** for invalid input - * **-EOPNOTSUPP** for unsupported delivery_time_type and protocol + * **-EOPNOTSUPP** for unsupported protocol */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -5314,7 +5313,7 @@ union bpf_attr { FN(xdp_load_bytes), \ FN(xdp_store_bytes), \ FN(copy_from_user_task), \ - FN(skb_set_delivery_time), \ + FN(skb_set_tstamp), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper @@ -5505,9 +5504,12 @@ union { \ } __attribute__((aligned(8))) enum { - BPF_SKB_DELIVERY_TIME_NONE, - BPF_SKB_DELIVERY_TIME_UNSPEC, - BPF_SKB_DELIVERY_TIME_MONO, + BPF_SKB_TSTAMP_UNSPEC, + BPF_SKB_TSTAMP_DELIVERY_MONO, /* tstamp has mono delivery time */ + /* For any BPF_SKB_TSTAMP_* that the bpf prog cannot handle, + * the bpf prog should handle it like BPF_SKB_TSTAMP_UNSPEC + * and try to deduce it by ingress, egress or skb->sk->sk_clockid. + */ }; /* user accessible mirror of in-kernel sk_buff. @@ -5550,7 +5552,7 @@ struct __sk_buff { __u32 gso_segs; __bpf_md_ptr(struct bpf_sock *, sk); __u32 gso_size; - __u8 delivery_time_type; + __u8 tstamp_type; __u32 :24; /* Padding, future use. */ __u64 hwtstamp; }; diff --git a/net/core/filter.c b/net/core/filter.c index f914e4b13b18..03655f2074ae 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -7388,36 +7388,36 @@ static const struct bpf_func_proto bpf_sock_ops_reserve_hdr_opt_proto = { .arg3_type = ARG_ANYTHING, }; -BPF_CALL_3(bpf_skb_set_delivery_time, struct sk_buff *, skb, - u64, dtime, u32, dtime_type) +BPF_CALL_3(bpf_skb_set_tstamp, struct sk_buff *, skb, + u64, tstamp, u32, tstamp_type) { /* skb_clear_delivery_time() is done for inet protocol */ if (skb->protocol != htons(ETH_P_IP) && skb->protocol != htons(ETH_P_IPV6)) return -EOPNOTSUPP; - switch (dtime_type) { - case BPF_SKB_DELIVERY_TIME_MONO: - if (!dtime) + switch (tstamp_type) { + case BPF_SKB_TSTAMP_DELIVERY_MONO: + if (!tstamp) return -EINVAL; - skb->tstamp = dtime; + skb->tstamp = tstamp; skb->mono_delivery_time = 1; break; - case BPF_SKB_DELIVERY_TIME_NONE: - if (dtime) + case BPF_SKB_TSTAMP_UNSPEC: + if (tstamp) return -EINVAL; skb->tstamp = 0; skb->mono_delivery_time = 0; break; default: - return -EOPNOTSUPP; + return -EINVAL; } return 0; } -static const struct bpf_func_proto bpf_skb_set_delivery_time_proto = { - .func = bpf_skb_set_delivery_time, +static const struct bpf_func_proto bpf_skb_set_tstamp_proto = { + .func = bpf_skb_set_tstamp, .gpl_only = false, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, @@ -7786,8 +7786,8 @@ tc_cls_act_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_tcp_gen_syncookie_proto; case BPF_FUNC_sk_assign: return &bpf_sk_assign_proto; - case BPF_FUNC_skb_set_delivery_time: - return &bpf_skb_set_delivery_time_proto; + case BPF_FUNC_skb_set_tstamp: + return &bpf_skb_set_tstamp_proto; #endif default: return bpf_sk_base_func_proto(func_id); @@ -8127,9 +8127,9 @@ static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type return false; info->reg_type = PTR_TO_SOCK_COMMON_OR_NULL; break; - case offsetof(struct __sk_buff, delivery_time_type): + case offsetof(struct __sk_buff, tstamp_type): return false; - case offsetofend(struct __sk_buff, delivery_time_type) ... offsetof(struct __sk_buff, hwtstamp) - 1: + case offsetofend(struct __sk_buff, tstamp_type) ... offsetof(struct __sk_buff, hwtstamp) - 1: /* Explicitly prohibit access to padding in __sk_buff. */ return false; default: @@ -8484,14 +8484,14 @@ static bool tc_cls_act_is_valid_access(int off, int size, break; case bpf_ctx_range_till(struct __sk_buff, family, local_port): return false; - case offsetof(struct __sk_buff, delivery_time_type): + case offsetof(struct __sk_buff, tstamp_type): /* The convert_ctx_access() on reading and writing * __sk_buff->tstamp depends on whether the bpf prog - * has used __sk_buff->delivery_time_type or not. - * Thus, we need to set prog->delivery_time_access + * has used __sk_buff->tstamp_type or not. + * Thus, we need to set prog->tstamp_type_access * earlier during is_valid_access() here. */ - ((struct bpf_prog *)prog)->delivery_time_access = 1; + ((struct bpf_prog *)prog)->tstamp_type_access = 1; return size == sizeof(__u8); } @@ -8888,42 +8888,22 @@ static u32 flow_dissector_convert_ctx_access(enum bpf_access_type type, return insn - insn_buf; } -static struct bpf_insn *bpf_convert_dtime_type_read(const struct bpf_insn *si, - struct bpf_insn *insn) +static struct bpf_insn *bpf_convert_tstamp_type_read(const struct bpf_insn *si, + struct bpf_insn *insn) { __u8 value_reg = si->dst_reg; __u8 skb_reg = si->src_reg; + /* AX is needed because src_reg and dst_reg could be the same */ __u8 tmp_reg = BPF_REG_AX; *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, PKT_VLAN_PRESENT_OFFSET); - *insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, - SKB_MONO_DELIVERY_TIME_MASK); - *insn++ = BPF_JMP32_IMM(BPF_JEQ, tmp_reg, 0, 2); - /* value_reg = BPF_SKB_DELIVERY_TIME_MONO */ - *insn++ = BPF_MOV32_IMM(value_reg, BPF_SKB_DELIVERY_TIME_MONO); - *insn++ = BPF_JMP_A(IS_ENABLED(CONFIG_NET_CLS_ACT) ? 10 : 5); - - *insn++ = BPF_LDX_MEM(BPF_DW, tmp_reg, skb_reg, - offsetof(struct sk_buff, tstamp)); - *insn++ = BPF_JMP_IMM(BPF_JNE, tmp_reg, 0, 2); - /* value_reg = BPF_SKB_DELIVERY_TIME_NONE */ - *insn++ = BPF_MOV32_IMM(value_reg, BPF_SKB_DELIVERY_TIME_NONE); - *insn++ = BPF_JMP_A(IS_ENABLED(CONFIG_NET_CLS_ACT) ? 6 : 1); - -#ifdef CONFIG_NET_CLS_ACT - *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, PKT_VLAN_PRESENT_OFFSET); - *insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, TC_AT_INGRESS_MASK); - *insn++ = BPF_JMP32_IMM(BPF_JEQ, tmp_reg, 0, 2); - /* At ingress, value_reg = 0 */ - *insn++ = BPF_MOV32_IMM(value_reg, 0); + *insn++ = BPF_JMP32_IMM(BPF_JSET, tmp_reg, + SKB_MONO_DELIVERY_TIME_MASK, 2); + *insn++ = BPF_MOV32_IMM(value_reg, BPF_SKB_TSTAMP_UNSPEC); *insn++ = BPF_JMP_A(1); -#endif - - /* value_reg = BPF_SKB_DELIVERYT_TIME_UNSPEC */ - *insn++ = BPF_MOV32_IMM(value_reg, BPF_SKB_DELIVERY_TIME_UNSPEC); + *insn++ = BPF_MOV32_IMM(value_reg, BPF_SKB_TSTAMP_DELIVERY_MONO); - /* 15 insns with CONFIG_NET_CLS_ACT */ return insn; } @@ -8956,11 +8936,11 @@ static struct bpf_insn *bpf_convert_tstamp_read(const struct bpf_prog *prog, __u8 skb_reg = si->src_reg; #ifdef CONFIG_NET_CLS_ACT - /* If the delivery_time_type is read, + /* If the tstamp_type is read, * the bpf prog is aware the tstamp could have delivery time. - * Thus, read skb->tstamp as is if delivery_time_access is true. + * Thus, read skb->tstamp as is if tstamp_type_access is true. */ - if (!prog->delivery_time_access) { + if (!prog->tstamp_type_access) { /* AX is needed because src_reg and dst_reg could be the same */ __u8 tmp_reg = BPF_REG_AX; @@ -8990,13 +8970,13 @@ static struct bpf_insn *bpf_convert_tstamp_write(const struct bpf_prog *prog, __u8 skb_reg = si->dst_reg; #ifdef CONFIG_NET_CLS_ACT - /* If the delivery_time_type is read, + /* If the tstamp_type is read, * the bpf prog is aware the tstamp could have delivery time. - * Thus, write skb->tstamp as is if delivery_time_access is true. + * Thus, write skb->tstamp as is if tstamp_type_access is true. * Otherwise, writing at ingress will have to clear the * mono_delivery_time bit also. */ - if (!prog->delivery_time_access) { + if (!prog->tstamp_type_access) { __u8 tmp_reg = BPF_REG_AX; *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, PKT_VLAN_PRESENT_OFFSET); @@ -9329,8 +9309,8 @@ static u32 bpf_convert_ctx_access(enum bpf_access_type type, insn = bpf_convert_tstamp_read(prog, si, insn); break; - case offsetof(struct __sk_buff, delivery_time_type): - insn = bpf_convert_dtime_type_read(si, insn); + case offsetof(struct __sk_buff, tstamp_type): + insn = bpf_convert_tstamp_type_read(si, insn); break; case offsetof(struct __sk_buff, gso_segs): diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index bc23020b638d..d288a0a9f797 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -5090,23 +5090,22 @@ union bpf_attr { * 0 on success, or a negative error in case of failure. On error * *dst* buffer is zeroed out. * - * long bpf_skb_set_delivery_time(struct sk_buff *skb, u64 dtime, u32 dtime_type) + * long bpf_skb_set_tstamp(struct sk_buff *skb, u64 tstamp, u32 tstamp_type) * Description - * Set a *dtime* (delivery time) to the __sk_buff->tstamp and also - * change the __sk_buff->delivery_time_type to *dtime_type*. + * Change the __sk_buff->tstamp_type to *tstamp_type* + * and set *tstamp* to the __sk_buff->tstamp together. * - * When setting a delivery time (non zero *dtime*) to - * __sk_buff->tstamp, only BPF_SKB_DELIVERY_TIME_MONO *dtime_type* - * is supported. It is the only delivery_time_type that will be - * kept after bpf_redirect_*(). - * - * If there is no need to change the __sk_buff->delivery_time_type, - * the delivery time can be directly written to __sk_buff->tstamp + * If there is no need to change the __sk_buff->tstamp_type, + * the tstamp value can be directly written to __sk_buff->tstamp * instead. * - * *dtime* 0 and *dtime_type* BPF_SKB_DELIVERY_TIME_NONE - * can be used to clear any delivery time stored in - * __sk_buff->tstamp. + * BPF_SKB_TSTAMP_DELIVERY_MONO is the only tstamp that + * will be kept during bpf_redirect_*(). A non zero + * *tstamp* must be used with the BPF_SKB_TSTAMP_DELIVERY_MONO + * *tstamp_type*. + * + * A BPF_SKB_TSTAMP_UNSPEC *tstamp_type* can only be used + * with a zero *tstamp*. * * Only IPv4 and IPv6 skb->protocol are supported. * @@ -5119,7 +5118,7 @@ union bpf_attr { * Return * 0 on success. * **-EINVAL** for invalid input - * **-EOPNOTSUPP** for unsupported delivery_time_type and protocol + * **-EOPNOTSUPP** for unsupported protocol */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -5314,7 +5313,7 @@ union bpf_attr { FN(xdp_load_bytes), \ FN(xdp_store_bytes), \ FN(copy_from_user_task), \ - FN(skb_set_delivery_time), \ + FN(skb_set_tstamp), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper @@ -5505,9 +5504,12 @@ union { \ } __attribute__((aligned(8))) enum { - BPF_SKB_DELIVERY_TIME_NONE, - BPF_SKB_DELIVERY_TIME_UNSPEC, - BPF_SKB_DELIVERY_TIME_MONO, + BPF_SKB_TSTAMP_UNSPEC, + BPF_SKB_TSTAMP_DELIVERY_MONO, /* tstamp has mono delivery time */ + /* For any BPF_SKB_TSTAMP_* that the bpf prog cannot handle, + * the bpf prog should handle it like BPF_SKB_TSTAMP_UNSPEC + * and try to deduce it by ingress, egress or skb->sk->sk_clockid. + */ }; /* user accessible mirror of in-kernel sk_buff. @@ -5550,7 +5552,7 @@ struct __sk_buff { __u32 gso_segs; __bpf_md_ptr(struct bpf_sock *, sk); __u32 gso_size; - __u8 delivery_time_type; + __u8 tstamp_type; __u32 :24; /* Padding, future use. */ __u64 hwtstamp; }; -- cgit v1.2.3 From 58617014405ad5c9f94f464444f4972dabb71ca7 Mon Sep 17 00:00:00 2001 From: Hengqi Chen Date: Thu, 10 Mar 2022 23:53:35 +0800 Subject: bpf: Fix comment for helper bpf_current_task_under_cgroup() Fix the descriptions of the return values of helper bpf_current_task_under_cgroup(). Fixes: c6b5fb8690fa ("bpf: add documentation for eBPF helpers (42-50)") Signed-off-by: Hengqi Chen Signed-off-by: Daniel Borkmann Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20220310155335.1278783-1-hengqi.chen@gmail.com --- include/uapi/linux/bpf.h | 4 ++-- tools/include/uapi/linux/bpf.h | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) (limited to 'tools/include/uapi') diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index d288a0a9f797..e9978a916c3e 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -2302,8 +2302,8 @@ union bpf_attr { * Return * The return value depends on the result of the test, and can be: * - * * 0, if current task belongs to the cgroup2. - * * 1, if current task does not belong to the cgroup2. + * * 1, if current task belongs to the cgroup2. + * * 0, if current task does not belong to the cgroup2. * * A negative error code, if an error occurred. * * long bpf_skb_change_tail(struct sk_buff *skb, u32 len, u64 flags) diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index d288a0a9f797..e9978a916c3e 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -2302,8 +2302,8 @@ union bpf_attr { * Return * The return value depends on the result of the test, and can be: * - * * 0, if current task belongs to the cgroup2. - * * 1, if current task does not belong to the cgroup2. + * * 1, if current task belongs to the cgroup2. + * * 0, if current task does not belong to the cgroup2. * * A negative error code, if an error occurred. * * long bpf_skb_change_tail(struct sk_buff *skb, u32 len, u64 flags) -- cgit v1.2.3 From 174b16946e39ebd369097e0f773536c91a8c1a4c Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Wed, 2 Mar 2022 12:13:58 +0100 Subject: bpf-lsm: Introduce new helper bpf_ima_file_hash() ima_file_hash() has been modified to calculate the measurement of a file on demand, if it has not been already performed by IMA or the measurement is not fresh. For compatibility reasons, ima_inode_hash() remains unchanged. Keep the same approach in eBPF and introduce the new helper bpf_ima_file_hash() to take advantage of the modified behavior of ima_file_hash(). Signed-off-by: Roberto Sassu Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20220302111404.193900-4-roberto.sassu@huawei.com --- include/uapi/linux/bpf.h | 11 +++++++++++ kernel/bpf/bpf_lsm.c | 20 ++++++++++++++++++++ tools/include/uapi/linux/bpf.h | 11 +++++++++++ 3 files changed, 42 insertions(+) (limited to 'tools/include/uapi') diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index e9978a916c3e..99fab54ae9c0 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -5119,6 +5119,16 @@ union bpf_attr { * 0 on success. * **-EINVAL** for invalid input * **-EOPNOTSUPP** for unsupported protocol + * + * long bpf_ima_file_hash(struct file *file, void *dst, u32 size) + * Description + * Returns a calculated IMA hash of the *file*. + * If the hash is larger than *size*, then only *size* + * bytes will be copied to *dst* + * Return + * The **hash_algo** is returned on success, + * **-EOPNOTSUP** if the hash calculation failed or **-EINVAL** if + * invalid arguments are passed. */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -5314,6 +5324,7 @@ union bpf_attr { FN(xdp_store_bytes), \ FN(copy_from_user_task), \ FN(skb_set_tstamp), \ + FN(ima_file_hash), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper diff --git a/kernel/bpf/bpf_lsm.c b/kernel/bpf/bpf_lsm.c index 9e4ecc990647..e8d27af5bbcc 100644 --- a/kernel/bpf/bpf_lsm.c +++ b/kernel/bpf/bpf_lsm.c @@ -99,6 +99,24 @@ static const struct bpf_func_proto bpf_ima_inode_hash_proto = { .allowed = bpf_ima_inode_hash_allowed, }; +BPF_CALL_3(bpf_ima_file_hash, struct file *, file, void *, dst, u32, size) +{ + return ima_file_hash(file, dst, size); +} + +BTF_ID_LIST_SINGLE(bpf_ima_file_hash_btf_ids, struct, file) + +static const struct bpf_func_proto bpf_ima_file_hash_proto = { + .func = bpf_ima_file_hash, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_BTF_ID, + .arg1_btf_id = &bpf_ima_file_hash_btf_ids[0], + .arg2_type = ARG_PTR_TO_UNINIT_MEM, + .arg3_type = ARG_CONST_SIZE, + .allowed = bpf_ima_inode_hash_allowed, +}; + static const struct bpf_func_proto * bpf_lsm_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) { @@ -121,6 +139,8 @@ bpf_lsm_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_bprm_opts_set_proto; case BPF_FUNC_ima_inode_hash: return prog->aux->sleepable ? &bpf_ima_inode_hash_proto : NULL; + case BPF_FUNC_ima_file_hash: + return prog->aux->sleepable ? &bpf_ima_file_hash_proto : NULL; default: return tracing_prog_func_proto(func_id, prog); } diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index e9978a916c3e..99fab54ae9c0 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -5119,6 +5119,16 @@ union bpf_attr { * 0 on success. * **-EINVAL** for invalid input * **-EOPNOTSUPP** for unsupported protocol + * + * long bpf_ima_file_hash(struct file *file, void *dst, u32 size) + * Description + * Returns a calculated IMA hash of the *file*. + * If the hash is larger than *size*, then only *size* + * bytes will be copied to *dst* + * Return + * The **hash_algo** is returned on success, + * **-EOPNOTSUP** if the hash calculation failed or **-EINVAL** if + * invalid arguments are passed. */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -5314,6 +5324,7 @@ union bpf_attr { FN(xdp_store_bytes), \ FN(copy_from_user_task), \ FN(skb_set_tstamp), \ + FN(ima_file_hash), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper -- cgit v1.2.3 From 0dcac272540613d41c05e89679e4ddb978b612f1 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Wed, 16 Mar 2022 13:24:09 +0100 Subject: bpf: Add multi kprobe link Adding new link type BPF_LINK_TYPE_KPROBE_MULTI that attaches kprobe program through fprobe API. The fprobe API allows to attach probe on multiple functions at once very fast, because it works on top of ftrace. On the other hand this limits the probe point to the function entry or return. The kprobe program gets the same pt_regs input ctx as when it's attached through the perf API. Adding new attach type BPF_TRACE_KPROBE_MULTI that allows attachment kprobe to multiple function with new link. User provides array of addresses or symbols with count to attach the kprobe program to. The new link_create uapi interface looks like: struct { __u32 flags; __u32 cnt; __aligned_u64 syms; __aligned_u64 addrs; } kprobe_multi; The flags field allows single BPF_TRACE_KPROBE_MULTI bit to create return multi kprobe. Signed-off-by: Masami Hiramatsu Signed-off-by: Jiri Olsa Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220316122419.933957-4-jolsa@kernel.org --- include/linux/bpf_types.h | 1 + include/linux/trace_events.h | 7 ++ include/uapi/linux/bpf.h | 13 +++ kernel/bpf/syscall.c | 26 ++++- kernel/trace/bpf_trace.c | 211 +++++++++++++++++++++++++++++++++++++++++ tools/include/uapi/linux/bpf.h | 13 +++ 6 files changed, 266 insertions(+), 5 deletions(-) (limited to 'tools/include/uapi') diff --git a/include/linux/bpf_types.h b/include/linux/bpf_types.h index 48a91c51c015..3e24ad0c4b3c 100644 --- a/include/linux/bpf_types.h +++ b/include/linux/bpf_types.h @@ -140,3 +140,4 @@ BPF_LINK_TYPE(BPF_LINK_TYPE_XDP, xdp) #ifdef CONFIG_PERF_EVENTS BPF_LINK_TYPE(BPF_LINK_TYPE_PERF_EVENT, perf) #endif +BPF_LINK_TYPE(BPF_LINK_TYPE_KPROBE_MULTI, kprobe_multi) diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index dcea51fb60e2..8f0e9e7cb493 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -15,6 +15,7 @@ struct array_buffer; struct tracer; struct dentry; struct bpf_prog; +union bpf_attr; const char *trace_print_flags_seq(struct trace_seq *p, const char *delim, unsigned long flags, @@ -738,6 +739,7 @@ void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp); int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id, u32 *fd_type, const char **buf, u64 *probe_offset, u64 *probe_addr); +int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog); #else static inline unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx) { @@ -779,6 +781,11 @@ static inline int bpf_get_perf_event_info(const struct perf_event *event, { return -EOPNOTSUPP; } +static inline int +bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) +{ + return -EOPNOTSUPP; +} #endif enum { diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 99fab54ae9c0..d77f47af7752 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -997,6 +997,7 @@ enum bpf_attach_type { BPF_SK_REUSEPORT_SELECT, BPF_SK_REUSEPORT_SELECT_OR_MIGRATE, BPF_PERF_EVENT, + BPF_TRACE_KPROBE_MULTI, __MAX_BPF_ATTACH_TYPE }; @@ -1011,6 +1012,7 @@ enum bpf_link_type { BPF_LINK_TYPE_NETNS = 5, BPF_LINK_TYPE_XDP = 6, BPF_LINK_TYPE_PERF_EVENT = 7, + BPF_LINK_TYPE_KPROBE_MULTI = 8, MAX_BPF_LINK_TYPE, }; @@ -1118,6 +1120,11 @@ enum bpf_link_type { */ #define BPF_F_XDP_HAS_FRAGS (1U << 5) +/* link_create.kprobe_multi.flags used in LINK_CREATE command for + * BPF_TRACE_KPROBE_MULTI attach type to create return probe. + */ +#define BPF_F_KPROBE_MULTI_RETURN (1U << 0) + /* When BPF ldimm64's insn[0].src_reg != 0 then this can have * the following extensions: * @@ -1475,6 +1482,12 @@ union bpf_attr { */ __u64 bpf_cookie; } perf_event; + struct { + __u32 flags; + __u32 cnt; + __aligned_u64 syms; + __aligned_u64 addrs; + } kprobe_multi; }; } link_create; diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 9beb585be5a6..b8bb67ee6c57 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -32,6 +32,7 @@ #include #include #include +#include #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \ (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \ @@ -3022,6 +3023,11 @@ out_put_file: fput(perf_file); return err; } +#else +static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) +{ + return -EOPNOTSUPP; +} #endif /* CONFIG_PERF_EVENTS */ #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd @@ -4255,7 +4261,7 @@ static int tracing_bpf_link_attach(const union bpf_attr *attr, bpfptr_t uattr, return -EINVAL; } -#define BPF_LINK_CREATE_LAST_FIELD link_create.iter_info_len +#define BPF_LINK_CREATE_LAST_FIELD link_create.kprobe_multi.addrs static int link_create(union bpf_attr *attr, bpfptr_t uattr) { enum bpf_prog_type ptype; @@ -4279,7 +4285,6 @@ static int link_create(union bpf_attr *attr, bpfptr_t uattr) ret = tracing_bpf_link_attach(attr, uattr, prog); goto out; case BPF_PROG_TYPE_PERF_EVENT: - case BPF_PROG_TYPE_KPROBE: case BPF_PROG_TYPE_TRACEPOINT: if (attr->link_create.attach_type != BPF_PERF_EVENT) { ret = -EINVAL; @@ -4287,6 +4292,14 @@ static int link_create(union bpf_attr *attr, bpfptr_t uattr) } ptype = prog->type; break; + case BPF_PROG_TYPE_KPROBE: + if (attr->link_create.attach_type != BPF_PERF_EVENT && + attr->link_create.attach_type != BPF_TRACE_KPROBE_MULTI) { + ret = -EINVAL; + goto out; + } + ptype = prog->type; + break; default: ptype = attach_type_to_prog_type(attr->link_create.attach_type); if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type) { @@ -4318,13 +4331,16 @@ static int link_create(union bpf_attr *attr, bpfptr_t uattr) ret = bpf_xdp_link_attach(attr, prog); break; #endif -#ifdef CONFIG_PERF_EVENTS case BPF_PROG_TYPE_PERF_EVENT: case BPF_PROG_TYPE_TRACEPOINT: - case BPF_PROG_TYPE_KPROBE: ret = bpf_perf_link_attach(attr, prog); break; -#endif + case BPF_PROG_TYPE_KPROBE: + if (attr->link_create.attach_type == BPF_PERF_EVENT) + ret = bpf_perf_link_attach(attr, prog); + else + ret = bpf_kprobe_multi_link_attach(attr, prog); + break; default: ret = -EINVAL; } diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index a2024ba32a20..fffa2171fae4 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -17,6 +17,7 @@ #include #include #include +#include #include @@ -2181,3 +2182,213 @@ static int __init bpf_event_init(void) fs_initcall(bpf_event_init); #endif /* CONFIG_MODULES */ + +#ifdef CONFIG_FPROBE +struct bpf_kprobe_multi_link { + struct bpf_link link; + struct fprobe fp; + unsigned long *addrs; +}; + +static void bpf_kprobe_multi_link_release(struct bpf_link *link) +{ + struct bpf_kprobe_multi_link *kmulti_link; + + kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link); + unregister_fprobe(&kmulti_link->fp); +} + +static void bpf_kprobe_multi_link_dealloc(struct bpf_link *link) +{ + struct bpf_kprobe_multi_link *kmulti_link; + + kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link); + kvfree(kmulti_link->addrs); + kfree(kmulti_link); +} + +static const struct bpf_link_ops bpf_kprobe_multi_link_lops = { + .release = bpf_kprobe_multi_link_release, + .dealloc = bpf_kprobe_multi_link_dealloc, +}; + +static int +kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link *link, + struct pt_regs *regs) +{ + int err; + + if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) { + err = 0; + goto out; + } + + migrate_disable(); + rcu_read_lock(); + err = bpf_prog_run(link->link.prog, regs); + rcu_read_unlock(); + migrate_enable(); + + out: + __this_cpu_dec(bpf_prog_active); + return err; +} + +static void +kprobe_multi_link_handler(struct fprobe *fp, unsigned long entry_ip, + struct pt_regs *regs) +{ + unsigned long saved_ip = instruction_pointer(regs); + struct bpf_kprobe_multi_link *link; + + /* + * Because fprobe's regs->ip is set to the next instruction of + * dynamic-ftrace instruction, correct entry ip must be set, so + * that the bpf program can access entry address via regs as same + * as kprobes. + * + * Both kprobe and kretprobe see the entry ip of traced function + * as instruction pointer. + */ + instruction_pointer_set(regs, entry_ip); + + link = container_of(fp, struct bpf_kprobe_multi_link, fp); + kprobe_multi_link_prog_run(link, regs); + + instruction_pointer_set(regs, saved_ip); +} + +static int +kprobe_multi_resolve_syms(const void *usyms, u32 cnt, + unsigned long *addrs) +{ + unsigned long addr, size; + const char **syms; + int err = -ENOMEM; + unsigned int i; + char *func; + + size = cnt * sizeof(*syms); + syms = kvzalloc(size, GFP_KERNEL); + if (!syms) + return -ENOMEM; + + func = kmalloc(KSYM_NAME_LEN, GFP_KERNEL); + if (!func) + goto error; + + if (copy_from_user(syms, usyms, size)) { + err = -EFAULT; + goto error; + } + + for (i = 0; i < cnt; i++) { + err = strncpy_from_user(func, syms[i], KSYM_NAME_LEN); + if (err == KSYM_NAME_LEN) + err = -E2BIG; + if (err < 0) + goto error; + err = -EINVAL; + addr = kallsyms_lookup_name(func); + if (!addr) + goto error; + if (!kallsyms_lookup_size_offset(addr, &size, NULL)) + goto error; + addr = ftrace_location_range(addr, addr + size - 1); + if (!addr) + goto error; + addrs[i] = addr; + } + + err = 0; +error: + kvfree(syms); + kfree(func); + return err; +} + +int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) +{ + struct bpf_kprobe_multi_link *link = NULL; + struct bpf_link_primer link_primer; + unsigned long *addrs; + u32 flags, cnt, size; + void __user *uaddrs; + void __user *usyms; + int err; + + /* no support for 32bit archs yet */ + if (sizeof(u64) != sizeof(void *)) + return -EOPNOTSUPP; + + if (prog->expected_attach_type != BPF_TRACE_KPROBE_MULTI) + return -EINVAL; + + flags = attr->link_create.kprobe_multi.flags; + if (flags & ~BPF_F_KPROBE_MULTI_RETURN) + return -EINVAL; + + uaddrs = u64_to_user_ptr(attr->link_create.kprobe_multi.addrs); + usyms = u64_to_user_ptr(attr->link_create.kprobe_multi.syms); + if (!!uaddrs == !!usyms) + return -EINVAL; + + cnt = attr->link_create.kprobe_multi.cnt; + if (!cnt) + return -EINVAL; + + size = cnt * sizeof(*addrs); + addrs = kvmalloc(size, GFP_KERNEL); + if (!addrs) + return -ENOMEM; + + if (uaddrs) { + if (copy_from_user(addrs, uaddrs, size)) { + err = -EFAULT; + goto error; + } + } else { + err = kprobe_multi_resolve_syms(usyms, cnt, addrs); + if (err) + goto error; + } + + link = kzalloc(sizeof(*link), GFP_KERNEL); + if (!link) { + err = -ENOMEM; + goto error; + } + + bpf_link_init(&link->link, BPF_LINK_TYPE_KPROBE_MULTI, + &bpf_kprobe_multi_link_lops, prog); + + err = bpf_link_prime(&link->link, &link_primer); + if (err) + goto error; + + if (flags & BPF_F_KPROBE_MULTI_RETURN) + link->fp.exit_handler = kprobe_multi_link_handler; + else + link->fp.entry_handler = kprobe_multi_link_handler; + + link->addrs = addrs; + + err = register_fprobe_ips(&link->fp, addrs, cnt); + if (err) { + bpf_link_cleanup(&link_primer); + return err; + } + + return bpf_link_settle(&link_primer); + +error: + kfree(link); + kvfree(addrs); + return err; +} +#else /* !CONFIG_FPROBE */ +int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) +{ + return -EOPNOTSUPP; +} +#endif diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 99fab54ae9c0..d77f47af7752 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -997,6 +997,7 @@ enum bpf_attach_type { BPF_SK_REUSEPORT_SELECT, BPF_SK_REUSEPORT_SELECT_OR_MIGRATE, BPF_PERF_EVENT, + BPF_TRACE_KPROBE_MULTI, __MAX_BPF_ATTACH_TYPE }; @@ -1011,6 +1012,7 @@ enum bpf_link_type { BPF_LINK_TYPE_NETNS = 5, BPF_LINK_TYPE_XDP = 6, BPF_LINK_TYPE_PERF_EVENT = 7, + BPF_LINK_TYPE_KPROBE_MULTI = 8, MAX_BPF_LINK_TYPE, }; @@ -1118,6 +1120,11 @@ enum bpf_link_type { */ #define BPF_F_XDP_HAS_FRAGS (1U << 5) +/* link_create.kprobe_multi.flags used in LINK_CREATE command for + * BPF_TRACE_KPROBE_MULTI attach type to create return probe. + */ +#define BPF_F_KPROBE_MULTI_RETURN (1U << 0) + /* When BPF ldimm64's insn[0].src_reg != 0 then this can have * the following extensions: * @@ -1475,6 +1482,12 @@ union bpf_attr { */ __u64 bpf_cookie; } perf_event; + struct { + __u32 flags; + __u32 cnt; + __aligned_u64 syms; + __aligned_u64 addrs; + } kprobe_multi; }; } link_create; -- cgit v1.2.3 From ca74823c6e16dd42b7cf60d9fdde80e2a81a67bb Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Wed, 16 Mar 2022 13:24:12 +0100 Subject: bpf: Add cookie support to programs attached with kprobe multi link Adding support to call bpf_get_attach_cookie helper from kprobe programs attached with kprobe multi link. The cookie is provided by array of u64 values, where each value is paired with provided function address or symbol with the same array index. When cookie array is provided it's sorted together with addresses (check bpf_kprobe_multi_cookie_swap). This way we can find cookie based on the address in bpf_get_attach_cookie helper. Suggested-by: Andrii Nakryiko Signed-off-by: Jiri Olsa Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20220316122419.933957-7-jolsa@kernel.org --- include/uapi/linux/bpf.h | 1 + kernel/bpf/syscall.c | 2 +- kernel/trace/bpf_trace.c | 114 ++++++++++++++++++++++++++++++++++++++++- tools/include/uapi/linux/bpf.h | 1 + 4 files changed, 116 insertions(+), 2 deletions(-) (limited to 'tools/include/uapi') diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index d77f47af7752..7604e7d5438f 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -1487,6 +1487,7 @@ union bpf_attr { __u32 cnt; __aligned_u64 syms; __aligned_u64 addrs; + __aligned_u64 cookies; } kprobe_multi; }; } link_create; diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index b8bb67ee6c57..cdaa1152436a 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -4261,7 +4261,7 @@ static int tracing_bpf_link_attach(const union bpf_attr *attr, bpfptr_t uattr, return -EINVAL; } -#define BPF_LINK_CREATE_LAST_FIELD link_create.kprobe_multi.addrs +#define BPF_LINK_CREATE_LAST_FIELD link_create.kprobe_multi.cookies static int link_create(union bpf_attr *attr, bpfptr_t uattr) { enum bpf_prog_type ptype; diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 0e7f8c9bc756..9a7b6be655e4 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -18,6 +18,8 @@ #include #include #include +#include +#include #include @@ -78,6 +80,7 @@ u64 bpf_get_stack(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5); static int bpf_btf_printf_prepare(struct btf_ptr *ptr, u32 btf_ptr_size, u64 flags, const struct btf **btf, s32 *btf_id); +static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx, u64 ip); /** * trace_call_bpf - invoke BPF program @@ -1050,6 +1053,18 @@ static const struct bpf_func_proto bpf_get_func_ip_proto_kprobe_multi = { .arg1_type = ARG_PTR_TO_CTX, }; +BPF_CALL_1(bpf_get_attach_cookie_kprobe_multi, struct pt_regs *, regs) +{ + return bpf_kprobe_multi_cookie(current->bpf_ctx, instruction_pointer(regs)); +} + +static const struct bpf_func_proto bpf_get_attach_cookie_proto_kmulti = { + .func = bpf_get_attach_cookie_kprobe_multi, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, +}; + BPF_CALL_1(bpf_get_attach_cookie_trace, void *, ctx) { struct bpf_trace_run_ctx *run_ctx; @@ -1297,7 +1312,9 @@ kprobe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) &bpf_get_func_ip_proto_kprobe_multi : &bpf_get_func_ip_proto_kprobe; case BPF_FUNC_get_attach_cookie: - return &bpf_get_attach_cookie_proto_trace; + return prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI ? + &bpf_get_attach_cookie_proto_kmulti : + &bpf_get_attach_cookie_proto_trace; default: return bpf_tracing_func_proto(func_id, prog); } @@ -2203,6 +2220,13 @@ struct bpf_kprobe_multi_link { struct bpf_link link; struct fprobe fp; unsigned long *addrs; + /* + * The run_ctx here is used to get struct bpf_kprobe_multi_link in + * get_attach_cookie helper, so it can't be used to store data. + */ + struct bpf_run_ctx run_ctx; + u64 *cookies; + u32 cnt; }; static void bpf_kprobe_multi_link_release(struct bpf_link *link) @@ -2219,6 +2243,7 @@ static void bpf_kprobe_multi_link_dealloc(struct bpf_link *link) kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link); kvfree(kmulti_link->addrs); + kvfree(kmulti_link->cookies); kfree(kmulti_link); } @@ -2227,10 +2252,60 @@ static const struct bpf_link_ops bpf_kprobe_multi_link_lops = { .dealloc = bpf_kprobe_multi_link_dealloc, }; +static void bpf_kprobe_multi_cookie_swap(void *a, void *b, int size, const void *priv) +{ + const struct bpf_kprobe_multi_link *link = priv; + unsigned long *addr_a = a, *addr_b = b; + u64 *cookie_a, *cookie_b; + unsigned long tmp1; + u64 tmp2; + + cookie_a = link->cookies + (addr_a - link->addrs); + cookie_b = link->cookies + (addr_b - link->addrs); + + /* swap addr_a/addr_b and cookie_a/cookie_b values */ + tmp1 = *addr_a; *addr_a = *addr_b; *addr_b = tmp1; + tmp2 = *cookie_a; *cookie_a = *cookie_b; *cookie_b = tmp2; +} + +static int __bpf_kprobe_multi_cookie_cmp(const void *a, const void *b) +{ + const unsigned long *addr_a = a, *addr_b = b; + + if (*addr_a == *addr_b) + return 0; + return *addr_a < *addr_b ? -1 : 1; +} + +static int bpf_kprobe_multi_cookie_cmp(const void *a, const void *b, const void *priv) +{ + return __bpf_kprobe_multi_cookie_cmp(a, b); +} + +static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx, u64 ip) +{ + struct bpf_kprobe_multi_link *link; + unsigned long *addr; + u64 *cookie; + + if (WARN_ON_ONCE(!ctx)) + return 0; + link = container_of(ctx, struct bpf_kprobe_multi_link, run_ctx); + if (!link->cookies) + return 0; + addr = bsearch(&ip, link->addrs, link->cnt, sizeof(ip), + __bpf_kprobe_multi_cookie_cmp); + if (!addr) + return 0; + cookie = link->cookies + (addr - link->addrs); + return *cookie; +} + static int kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link *link, struct pt_regs *regs) { + struct bpf_run_ctx *old_run_ctx; int err; if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) { @@ -2240,7 +2315,9 @@ kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link *link, migrate_disable(); rcu_read_lock(); + old_run_ctx = bpf_set_run_ctx(&link->run_ctx); err = bpf_prog_run(link->link.prog, regs); + bpf_reset_run_ctx(old_run_ctx); rcu_read_unlock(); migrate_enable(); @@ -2326,9 +2403,11 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr { struct bpf_kprobe_multi_link *link = NULL; struct bpf_link_primer link_primer; + void __user *ucookies; unsigned long *addrs; u32 flags, cnt, size; void __user *uaddrs; + u64 *cookies = NULL; void __user *usyms; int err; @@ -2368,6 +2447,19 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr goto error; } + ucookies = u64_to_user_ptr(attr->link_create.kprobe_multi.cookies); + if (ucookies) { + cookies = kvmalloc(size, GFP_KERNEL); + if (!cookies) { + err = -ENOMEM; + goto error; + } + if (copy_from_user(cookies, ucookies, size)) { + err = -EFAULT; + goto error; + } + } + link = kzalloc(sizeof(*link), GFP_KERNEL); if (!link) { err = -ENOMEM; @@ -2387,6 +2479,21 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr link->fp.entry_handler = kprobe_multi_link_handler; link->addrs = addrs; + link->cookies = cookies; + link->cnt = cnt; + + if (cookies) { + /* + * Sorting addresses will trigger sorting cookies as well + * (check bpf_kprobe_multi_cookie_swap). This way we can + * find cookie based on the address in bpf_get_attach_cookie + * helper. + */ + sort_r(addrs, cnt, sizeof(*addrs), + bpf_kprobe_multi_cookie_cmp, + bpf_kprobe_multi_cookie_swap, + link); + } err = register_fprobe_ips(&link->fp, addrs, cnt); if (err) { @@ -2399,6 +2506,7 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr error: kfree(link); kvfree(addrs); + kvfree(cookies); return err; } #else /* !CONFIG_FPROBE */ @@ -2406,4 +2514,8 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr { return -EOPNOTSUPP; } +static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx, u64 ip) +{ + return 0; +} #endif diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index d77f47af7752..7604e7d5438f 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -1487,6 +1487,7 @@ union bpf_attr { __u32 cnt; __aligned_u64 syms; __aligned_u64 addrs; + __aligned_u64 cookies; } kprobe_multi; }; } link_create; -- cgit v1.2.3