From a5bbcbf29089a1252c201b1a7fd38151de355db9 Mon Sep 17 00:00:00 2001 From: Taehee Yoo Date: Sun, 15 Nov 2020 10:30:41 +0000 Subject: netdevsim: set .owner to THIS_MODULE If THIS_MODULE is not set, the module would be removed while debugfs is being used. It eventually makes kernel panic. Fixes: 82c93a87bf8b ("netdevsim: implement couple of testing devlink health reporters") Fixes: 424be63ad831 ("netdevsim: add UDP tunnel port offload support") Fixes: 4418f862d675 ("netdevsim: implement support for devlink region and snapshots") Fixes: d3cbb907ae57 ("netdevsim: add ACL trap reporting cookie as a metadata") Signed-off-by: Taehee Yoo Link: https://lore.kernel.org/r/20201115103041.30701-1-ap420073@gmail.com Signed-off-by: Jakub Kicinski --- drivers/net/netdevsim/dev.c | 2 ++ drivers/net/netdevsim/health.c | 1 + drivers/net/netdevsim/udp_tunnels.c | 1 + 3 files changed, 4 insertions(+) (limited to 'drivers/net/netdevsim') diff --git a/drivers/net/netdevsim/dev.c b/drivers/net/netdevsim/dev.c index d07061417675..e7972e88ffe0 100644 --- a/drivers/net/netdevsim/dev.c +++ b/drivers/net/netdevsim/dev.c @@ -96,6 +96,7 @@ static const struct file_operations nsim_dev_take_snapshot_fops = { .open = simple_open, .write = nsim_dev_take_snapshot_write, .llseek = generic_file_llseek, + .owner = THIS_MODULE, }; static ssize_t nsim_dev_trap_fa_cookie_read(struct file *file, @@ -188,6 +189,7 @@ static const struct file_operations nsim_dev_trap_fa_cookie_fops = { .read = nsim_dev_trap_fa_cookie_read, .write = nsim_dev_trap_fa_cookie_write, .llseek = generic_file_llseek, + .owner = THIS_MODULE, }; static int nsim_dev_debugfs_init(struct nsim_dev *nsim_dev) diff --git a/drivers/net/netdevsim/health.c b/drivers/net/netdevsim/health.c index 62958b238d50..21e2974660e7 100644 --- a/drivers/net/netdevsim/health.c +++ b/drivers/net/netdevsim/health.c @@ -261,6 +261,7 @@ static const struct file_operations nsim_dev_health_break_fops = { .open = simple_open, .write = nsim_dev_health_break_write, .llseek = generic_file_llseek, + .owner = THIS_MODULE, }; int nsim_dev_health_init(struct nsim_dev *nsim_dev, struct devlink *devlink) diff --git a/drivers/net/netdevsim/udp_tunnels.c b/drivers/net/netdevsim/udp_tunnels.c index 6ab023acefd6..02dc3123eb6c 100644 --- a/drivers/net/netdevsim/udp_tunnels.c +++ b/drivers/net/netdevsim/udp_tunnels.c @@ -124,6 +124,7 @@ static const struct file_operations nsim_udp_tunnels_info_reset_fops = { .open = simple_open, .write = nsim_udp_tunnels_info_reset_write, .llseek = generic_file_llseek, + .owner = THIS_MODULE, }; int nsim_udp_tunnels_info_create(struct nsim_dev *nsim_dev, -- cgit v1.2.3 From 998f17296234aa8d3676b4a13962eb39f4ad24e0 Mon Sep 17 00:00:00 2001 From: Toke Høiland-Jørgensen Date: Wed, 9 Dec 2020 14:57:37 +0100 Subject: xdp: Remove the xdp_attachment_flags_ok() callback MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Since commit 7f0a838254bd ("bpf, xdp: Maintain info on attached XDP BPF programs in net_device"), the XDP program attachment info is now maintained in the core code. This interacts badly with the xdp_attachment_flags_ok() check that prevents unloading an XDP program with different load flags than it was loaded with. In practice, two kinds of failures are seen: - An XDP program loaded without specifying a mode (and which then ends up in driver mode) cannot be unloaded if the program mode is specified on unload. - The dev_xdp_uninstall() hook always calls the driver callback with the mode set to the type of the program but an empty flags argument, which means the flags_ok() check prevents the program from being removed, leading to bpf prog reference leaks. The original reason this check was added was to avoid ambiguity when multiple programs were loaded. With the way the checks are done in the core now, this is quite simple to enforce in the core code, so let's add a check there and get rid of the xdp_attachment_flags_ok() callback entirely. Fixes: 7f0a838254bd ("bpf, xdp: Maintain info on attached XDP BPF programs in net_device") Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Daniel Borkmann Acked-by: Jakub Kicinski Link: https://lore.kernel.org/bpf/160752225751.110217.10267659521308669050.stgit@toke.dk --- .../net/ethernet/netronome/nfp/nfp_net_common.c | 6 ------ drivers/net/ethernet/ti/cpsw_priv.c | 3 --- drivers/net/netdevsim/bpf.c | 3 --- include/net/xdp.h | 2 -- net/core/dev.c | 22 ++++++++++++++++++++-- net/core/xdp.c | 12 ------------ 6 files changed, 20 insertions(+), 28 deletions(-) (limited to 'drivers/net/netdevsim') diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c index b150da43adb2..437226866ce8 100644 --- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c +++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c @@ -3562,9 +3562,6 @@ static int nfp_net_xdp_setup_drv(struct nfp_net *nn, struct netdev_bpf *bpf) struct nfp_net_dp *dp; int err; - if (!xdp_attachment_flags_ok(&nn->xdp, bpf)) - return -EBUSY; - if (!prog == !nn->dp.xdp_prog) { WRITE_ONCE(nn->dp.xdp_prog, prog); xdp_attachment_setup(&nn->xdp, bpf); @@ -3593,9 +3590,6 @@ static int nfp_net_xdp_setup_hw(struct nfp_net *nn, struct netdev_bpf *bpf) { int err; - if (!xdp_attachment_flags_ok(&nn->xdp_hw, bpf)) - return -EBUSY; - err = nfp_app_xdp_offload(nn->app, nn, bpf->prog, bpf->extack); if (err) return err; diff --git a/drivers/net/ethernet/ti/cpsw_priv.c b/drivers/net/ethernet/ti/cpsw_priv.c index 31c5e36ff706..424e644724e4 100644 --- a/drivers/net/ethernet/ti/cpsw_priv.c +++ b/drivers/net/ethernet/ti/cpsw_priv.c @@ -1265,9 +1265,6 @@ static int cpsw_xdp_prog_setup(struct cpsw_priv *priv, struct netdev_bpf *bpf) if (!priv->xdpi.prog && !prog) return 0; - if (!xdp_attachment_flags_ok(&priv->xdpi, bpf)) - return -EBUSY; - WRITE_ONCE(priv->xdp_prog, prog); xdp_attachment_setup(&priv->xdpi, bpf); diff --git a/drivers/net/netdevsim/bpf.c b/drivers/net/netdevsim/bpf.c index 2e90512f3bbe..85546664bdd5 100644 --- a/drivers/net/netdevsim/bpf.c +++ b/drivers/net/netdevsim/bpf.c @@ -190,9 +190,6 @@ nsim_xdp_set_prog(struct netdevsim *ns, struct netdev_bpf *bpf, { int err; - if (!xdp_attachment_flags_ok(xdp, bpf)) - return -EBUSY; - if (bpf->command == XDP_SETUP_PROG && !ns->bpf_xdpdrv_accept) { NSIM_EA(bpf->extack, "driver XDP disabled in DebugFS"); return -EOPNOTSUPP; diff --git a/include/net/xdp.h b/include/net/xdp.h index 3814fb631d52..9dab2bc6f187 100644 --- a/include/net/xdp.h +++ b/include/net/xdp.h @@ -240,8 +240,6 @@ struct xdp_attachment_info { }; struct netdev_bpf; -bool xdp_attachment_flags_ok(struct xdp_attachment_info *info, - struct netdev_bpf *bpf); void xdp_attachment_setup(struct xdp_attachment_info *info, struct netdev_bpf *bpf); diff --git a/net/core/dev.c b/net/core/dev.c index 8588ade790cb..38412e70f761 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -8917,6 +8917,17 @@ static struct bpf_prog *dev_xdp_prog(struct net_device *dev, return dev->xdp_state[mode].prog; } +static u8 dev_xdp_prog_count(struct net_device *dev) +{ + u8 count = 0; + int i; + + for (i = 0; i < __MAX_XDP_MODE; i++) + if (dev->xdp_state[i].prog || dev->xdp_state[i].link) + count++; + return count; +} + u32 dev_xdp_prog_id(struct net_device *dev, enum bpf_xdp_mode mode) { struct bpf_prog *prog = dev_xdp_prog(dev, mode); @@ -9007,6 +9018,7 @@ static int dev_xdp_attach(struct net_device *dev, struct netlink_ext_ack *extack struct bpf_xdp_link *link, struct bpf_prog *new_prog, struct bpf_prog *old_prog, u32 flags) { + unsigned int num_modes = hweight32(flags & XDP_FLAGS_MODES); struct bpf_prog *cur_prog; enum bpf_xdp_mode mode; bpf_op_t bpf_op; @@ -9022,11 +9034,17 @@ static int dev_xdp_attach(struct net_device *dev, struct netlink_ext_ack *extack NL_SET_ERR_MSG(extack, "Invalid XDP flags for BPF link attachment"); return -EINVAL; } - /* just one XDP mode bit should be set, zero defaults to SKB mode */ - if (hweight32(flags & XDP_FLAGS_MODES) > 1) { + /* just one XDP mode bit should be set, zero defaults to drv/skb mode */ + if (num_modes > 1) { NL_SET_ERR_MSG(extack, "Only one XDP mode flag can be set"); return -EINVAL; } + /* avoid ambiguity if offload + drv/skb mode progs are both loaded */ + if (!num_modes && dev_xdp_prog_count(dev) > 1) { + NL_SET_ERR_MSG(extack, + "More than one program loaded, unset mode is ambiguous"); + return -EINVAL; + } /* old_prog != NULL implies XDP_FLAGS_REPLACE is set */ if (old_prog && !(flags & XDP_FLAGS_REPLACE)) { NL_SET_ERR_MSG(extack, "XDP_FLAGS_REPLACE is not specified"); diff --git a/net/core/xdp.c b/net/core/xdp.c index 491ad569a79c..d900cebc0acd 100644 --- a/net/core/xdp.c +++ b/net/core/xdp.c @@ -403,18 +403,6 @@ void __xdp_release_frame(void *data, struct xdp_mem_info *mem) } EXPORT_SYMBOL_GPL(__xdp_release_frame); -bool xdp_attachment_flags_ok(struct xdp_attachment_info *info, - struct netdev_bpf *bpf) -{ - if (info->prog && (bpf->flags ^ info->flags) & XDP_FLAGS_MODES) { - NL_SET_ERR_MSG(bpf->extack, - "program loaded with different flags"); - return false; - } - return true; -} -EXPORT_SYMBOL_GPL(xdp_attachment_flags_ok); - void xdp_attachment_setup(struct xdp_attachment_info *info, struct netdev_bpf *bpf) { -- cgit v1.2.3 From e4ff5aa469403462091eb22e2b0843b894167e10 Mon Sep 17 00:00:00 2001 From: Toke Høiland-Jørgensen Date: Wed, 9 Dec 2020 14:57:39 +0100 Subject: netdevsim: Add debugfs toggle to reject BPF programs in verifier MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This adds a new debugfs toggle ('bpf_bind_verifier_accept') that can be used to make netdevsim reject BPF programs from being accepted by the verifier. If this toggle (which defaults to true) is set to false, nsim_bpf_verify_insn() will return EOPNOTSUPP on the last instruction (after outputting the 'Hello from netdevsim' verifier message). This makes it possible to check the verification callback in the driver from test_offload.py in selftests, since the verifier now clears the verifier log on a successful load, hiding the message from the driver. Fixes: 6f8a57ccf851 ("bpf: Make verifier log more relevant by default") Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Daniel Borkmann Acked-by: Jakub Kicinski Link: https://lore.kernel.org/bpf/160752225964.110217.12584017165318065332.stgit@toke.dk --- drivers/net/netdevsim/bpf.c | 12 ++++++++++-- drivers/net/netdevsim/netdevsim.h | 1 + 2 files changed, 11 insertions(+), 2 deletions(-) (limited to 'drivers/net/netdevsim') diff --git a/drivers/net/netdevsim/bpf.c b/drivers/net/netdevsim/bpf.c index 85546664bdd5..90aafb56f140 100644 --- a/drivers/net/netdevsim/bpf.c +++ b/drivers/net/netdevsim/bpf.c @@ -63,15 +63,20 @@ static int nsim_bpf_verify_insn(struct bpf_verifier_env *env, int insn_idx, int prev_insn) { struct nsim_bpf_bound_prog *state; + int ret = 0; state = env->prog->aux->offload->dev_priv; if (state->nsim_dev->bpf_bind_verifier_delay && !insn_idx) msleep(state->nsim_dev->bpf_bind_verifier_delay); - if (insn_idx == env->prog->len - 1) + if (insn_idx == env->prog->len - 1) { pr_vlog(env, "Hello from netdevsim!\n"); - return 0; + if (!state->nsim_dev->bpf_bind_verifier_accept) + ret = -EOPNOTSUPP; + } + + return ret; } static int nsim_bpf_finalize(struct bpf_verifier_env *env) @@ -595,6 +600,9 @@ int nsim_bpf_dev_init(struct nsim_dev *nsim_dev) &nsim_dev->bpf_bind_accept); debugfs_create_u32("bpf_bind_verifier_delay", 0600, nsim_dev->ddir, &nsim_dev->bpf_bind_verifier_delay); + nsim_dev->bpf_bind_verifier_accept = true; + debugfs_create_bool("bpf_bind_verifier_accept", 0600, nsim_dev->ddir, + &nsim_dev->bpf_bind_verifier_accept); return 0; } diff --git a/drivers/net/netdevsim/netdevsim.h b/drivers/net/netdevsim/netdevsim.h index 827fc80f50a0..c4e7ad2a1964 100644 --- a/drivers/net/netdevsim/netdevsim.h +++ b/drivers/net/netdevsim/netdevsim.h @@ -189,6 +189,7 @@ struct nsim_dev { struct dentry *take_snapshot; struct bpf_offload_dev *bpf_dev; bool bpf_bind_accept; + bool bpf_bind_verifier_accept; u32 bpf_bind_verifier_delay; struct dentry *ddir_bpf_bound_progs; u32 prog_id_gen; -- cgit v1.2.3