| Age | Commit message (Collapse) | Author |
|
git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Pull bpf updates from Alexei Starovoitov:
"Major changes:
- Introduce scalar evolution (SCEV) analysis in the verifier.
It infers how registers and stack slots change in a loop and lets
the verifier check bounded loops with induction variables as ranges
instead of walking every iteration. The number of processed insns
drops ten fold in programs with loops (Eduard Zingerman)
- Add 'callx' instruction: indirect call of a static BPF subprogram.
The address is taken with ld_imm64 or loaded from read-only data.
Supported by x86-64, arm64 and riscv64 JITs (Alexei Starovoitov, Pu
Lehui)
- Add unwind_goto and unwind_exit instructions, so that Rust panic or
C++ exception can run destructors of every frame it passes through.
The normal path is free of unwind code. Supported by x86-64 and
arm64 JITs (Alexei Starovoitov)
- Support programs compiled by rust-bpf: treat load and store through
a number as arena access with BPF_F_ARENA_SCALAR, accept rust names
in BTF (Alexei Starovoitov)
- Raise BPF program stack size from 512 bytes to 2 KiB on x86-64 and
arm64 (Kumar Kartikeya Dwivedi)
- Support struct, union and __int128 up to 16 bytes passed and
returned by value in BPF subprograms and kfuncs, and fix x86-64 and
arm64 trampolines for such arguments (Yonghong Song)
- Introduce a common way to attach struct_ops to a cgroup via
bpf_link. bpf_tcp_ops is the first user and mirrors TCP sock_ops
callbacks (Martin KaFai Lau, Amery Hung)
- Describe inlined functions in BTF. New kinds tell where the inline
sites are and how to fetch the arguments there.
CONFIG_DEBUG_INFO_BTF_INLINE keeps it apart from the main BTF in
.BTF.inline section or in btf_vmlinux_inline.ko (Alan Maguire)
- Fix many memory safety, lifetime and locking bugs in BPF core,
verifier, iterators, local storage, dynptr, devmap, cpumap and
seg6local (Josef Bacik, Alexei Starovoitov)
- Diff stat is dominated by selftests and by removal of
lib/test_bpf.c. Its 16k lines of instruction tests were converted
to BPF selftests that BPF CI runs on every architecture it covers
(Daniel Borkmann)
Other features and fixes:
- Add KASAN checks to memory accesses of JITed programs on x86-64
(Alexis Lothoré)
- Complete unification of helper, kfunc and subprog argument checks
in the verifier (Amery Hung)
- Add bpf_copy_from_user_mm[_str]() kfuncs (Anastasios Papagiannis)
- Various features and fixes (Daniel Borkmann):
- Add .bpf keyring for program signature verification, modelled
after dm-verity keyring, and support ML-DSA in signing tools
- Emit shorter and faster code in x86-64 JIT for patterns that
LLVM generates
- Fix various issues in gotox handling
- Let BPF LSM set xattrs at inode creation with bpf_inode_init_xattr()
(David Windsor, Daniel Borkmann)
- Use sleepable page allocation in sleepable arena paths. Fix races
between arena free, allocation and user page fault (Emil Tsalapatis)
- Switch BPF crypto from lskcipher to AES-CBC and AES-ECB libraries
(Eric Biggers)
- Add bpf_proactive_reclaim() kfunc (Hui Zhu)
- Render decl_tags in libbpf btf_dump and add tests for bpftool C
dump (Ihor Solodrai)
- Speed up tracing_multi attach on x86 (Jiri Olsa)
- Various features and fixes (Kumar Kartikeya Dwivedi):
- Add BPF_PROG_STREAM_OPEN command to read BPF streams through a
file descriptor with poll support
- Let kernel structs publish arena pointers with __arena type tag
- Fix __uninit kfunc output buffers and fastcall rewrite with
indirect stack accesses
- Refuse CO-RE relocations for signed programs
- Add enqueue_rcvq and dequeue_rcvq hooks to bpf_tcp_ops to adjust
sk_rcvlowat and avoid unnecessary wakeups (Kuniyuki Iwashima)
- Add bpf_ksock_sendto() kfunc and allow ksock connect and send from
bpf_wq (Mahe Tardy)
- Fix racy plt target update in arm64 bpf_arch_text_poke()
(Matthew Wood)
- Restructure BPF selftests Makefile as a layered build
(Mykola Lysenko)
- Speed up hash map lookups for u32 and u64 keys (Mykyta Yatsenko)
- Add signed div/mod, movsx, bswap and gotol to MIPS JITs, signed
div/mod to parisc JITs (Nicholas Dudar, Johan Almbladh)
- Fix stack overflow in build ID parser on 32-bit (Nickolai
Zeldovich)
- Add stack arguments, signed arena loads and gotox to riscv64 JIT.
Pu Lehui is now co-maintainer of riscv BPF JITs (Pu Lehui, Chen
Pei, Feng Jiang)
- Add bpf_call_rcu() and bpf_call_rcu_tasks_trace() kfuncs. Support
fetching and/or/xor atomics in arena on x86-64 (Puranjay Mohan)
- Fix flaky selftests, selftests with clang 23 and bpf-gcc
(Qiliang Yuan, KaFai Wan, Vineet Gupta)
- Fix builds broken by fatal resolve_btfids warnings, BTF generation
on ARC, and define arch_cmpxchg_local() on arc, hexagon and
openrisc (Sasha Levin)
- Reduce memory use of hash maps by up to 50% per element
(T.J. Mercier)
- Mark pointer fields of sched_ext ops arguments as trusted (Tejun
Heo)
- Remove legacy bpf_asm, bpf_dbg and bpf_jit_disasm tools (Xia Yan)
- Fix index overflow in queue and stack maps, arena range tree after
allocation failure, tail call loop after freplace detach, lost
signal in bpf_send_signal() (Yuan Chen)
- Many more fixes and cleanups"
* tag 'bpf-next-7.4' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (660 commits)
selftests/bpf: Time tc_edt from its first packet with data
selftests/bpf: Test unwind_exit of an exception callback
selftests/bpf: Tests for 32-bit scalar evolution bounds computation
bpf: Reject unwind_goto and unwind_exit in offloaded progs
bpf: Support 32-bit linear scalar evolution
bpf: Make unwind_exit of an exception callback exit in JITs
selftests/bpf: Test forbidden bpf_ksock_sendto() LSM attach
selftests/bpf: Test ksock sendto()
bpf: Add bpf_ksock_sendto() kfunc
selftests/bpf: Test unwinding from R0: R2 subprog
selftests/bpf: Add a C++ prog with exceptions
selftests/bpf: Add tests for unwind_goto and unwind_exit
bpf, arm64: Support unwind_goto and unwind_exit
bpf, x86: Support unwind_goto and unwind_exit
bpf: Add unwind_goto and unwind_exit insns
tools/bpf: Remove legacy BPF tools
bpf: Annotate data races on bpf_lru_node type
selftests/bpf: Add arena allocation race tests
bpf: Fix arena race between page free and alloc leading to incoherency
bpf: Revalidate faulted arena pages before installing user mappings
...
|
|
bpf_token_create() allocates a bpffs inode and hands it to
alloc_file_pseudo(). The inode reference only moves to the new file when
that call succeeds: alloc_file_pseudo() leaves the caller's reference alone
on failure, and FD_PREPARE() does not even evaluate the file expression
when it cannot get a descriptor.
Before the conversion to FD_PREPARE() the error path did iput(inode). The
conversion dropped it, so each BPF_TOKEN_CREATE that fails with -EMFILE,
-ENFILE or -ENOMEM at this point leaks an inode. A task that is allowed to
create tokens can hit this at will by lowering RLIMIT_NOFILE, and the
leaked inodes make umount of that bpffs instance complain about busy
inodes.
Put the inode again if no file was created.
Fixes: 981bec8f698b ("bpf: convert bpf_token_create() to FD_PREPARE()")
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://patch.msgid.link/20261017163745.3341787-4-alexei.starovoitov@gmail.com
|
|
FD_PREPARE() releases the fd as soon as the file expression fails. The
fd either holds the descriptor or the error. The separate field is
redundant. Make fd and file plain members and struct fd_prepare simpler.
Callers of FD_PREPARE() get a const pointer to the guard. Simplify all
users as they can now easily access the trivial struct.
No functional changes.
Link: https://patch.msgid.link/20260917-work-file-fd_prepare-v1-4-b87534ca49f3@kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
|
|
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
|
|
Add GPL-2.0 SPDX-License-Identifier lines to some files,
and remove a reference to COPYING, and boilerplate warranty
text, from offload.c.
Signed-off-by: Tim Bird <tim.bird@sony.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260115013129.598705-1-tim.bird@sony.com
|
|
Link: https://patch.msgid.link/20251123-work-fd-prepare-v4-24-b6efa1706cfd@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
|
|
The 'commit 35f96de04127 ("bpf: Introduce BPF token object")' added
BPF token as a new kind of BPF kernel object. And BPF_OBJ_GET_INFO_BY_FD
already used to get BPF object info, so we can also get token info with
this cmd.
One usage scenario, when program runs failed with token, because of
the permission failure, we can report what BPF token is allowing with
this API for debugging.
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Tao Chen <chen.dylane@linux.dev>
Link: https://lore.kernel.org/r/20250716134654.1162635-1-chen.dylane@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
some of those used to be needed, some had been cargo-culted for
no reason...
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
|
Keep file reference through the entire thing, don't bother with grabbing
struct path reference and while we are at it, don't confuse the hell out
of readers by random mix of path.dentry->d_sb and path.mnt->mnt_sb uses -
these two are equal, so just put one of those into a local variable and
use that.
Reviewed-by: Christian Brauner <brauner@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
|
|
fdget() is the first thing done in scope, all matching fdput() are
immediately followed by leaving the scope.
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
|
|
For any changes of struct fd representation we need to
turn existing accesses to fields into calls of wrappers.
Accesses to struct fd::flags are very few (3 in linux/file.h,
1 in net/socket.c, 3 in fs/overlayfs/file.c and 3 more in
explicit initializers).
Those can be dealt with in the commit converting to
new layout; accesses to struct fd::file are too many for that.
This commit converts (almost) all of f.file to
fd_file(f). It's not entirely mechanical ('file' is used as
a member name more than just in struct fd) and it does not
even attempt to distinguish the uses in pointer context from
those in boolean context; the latter will be eventually turned
into a separate helper (fd_empty()).
NOTE: mass conversion to fd_empty(), tempting as it
might be, is a bad idea; better do that piecewise in commit
that convert from fdget...() to CLASS(...).
[conflicts in fs/fhandle.c, kernel/bpf/syscall.c, mm/memcontrol.c
caught by git; fs/stat.c one got caught by git grep]
[fs/xattr.c conflict]
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
|
Replace the '(1ULL << *)' with the macro BIT_ULL(nr).
Signed-off-by: Haiyue Wang <haiyue.wang@intel.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240127134901.3698613-1-haiyue.wang@intel.com
|
|
It's quite confusing in practice when it's possible to successfully
create a BPF token from BPF FS that didn't have any of delegate_xxx
mount options set up. While it's not wrong, it's actually more
meaningful to reject BPF_TOKEN_CREATE with specific error code (-ENOENT)
to let user-space know that no token delegation is setup up.
So, instead of creating empty BPF token that will be always ignored
because it doesn't have any of the allow_xxx bits set, reject it with
-ENOENT. If we ever need empty BPF token to be possible, we can support
that with extra flag passed into BPF_TOKEN_CREATE.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Christian Brauner <brauner@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20240124022127.2379740-19-andrii@kernel.org
|
|
Wire up bpf_token_create and bpf_token_free LSM hooks, which allow to
allocate LSM security blob (we add `void *security` field to struct
bpf_token for that), but also control who can instantiate BPF token.
This follows existing pattern for BPF map and BPF prog.
Also add security_bpf_token_allow_cmd() and security_bpf_token_capable()
LSM hooks that allow LSM implementation to control and negate (if
necessary) BPF token's delegation of a specific bpf_cmd and capability,
respectively.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Paul Moore <paul@paul-moore.com>
Link: https://lore.kernel.org/bpf/20240124022127.2379740-12-andrii@kernel.org
|
|
Add basic support of BPF token to BPF_PROG_LOAD. BPF_F_TOKEN_FD flag
should be set in prog_flags field when providing prog_token_fd.
Wire through a set of allowed BPF program types and attach types,
derived from BPF FS at BPF token creation time. Then make sure we
perform bpf_token_capable() checks everywhere where it's relevant.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20240124022127.2379740-7-andrii@kernel.org
|
|
Allow providing token_fd for BPF_MAP_CREATE command to allow controlled
BPF map creation from unprivileged process through delegated BPF token.
New BPF_F_TOKEN_FD flag is added to specify together with BPF token FD
for BPF_MAP_CREATE command.
Wire through a set of allowed BPF map types to BPF token, derived from
BPF FS at BPF token creation time. This, in combination with allowed_cmds
allows to create a narrowly-focused BPF token (controlled by privileged
agent) with a restrictive set of BPF maps that application can attempt
to create.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20240124022127.2379740-5-andrii@kernel.org
|
|
Add new kind of BPF kernel object, BPF token. BPF token is meant to
allow delegating privileged BPF functionality, like loading a BPF
program or creating a BPF map, from privileged process to a *trusted*
unprivileged process, all while having a good amount of control over which
privileged operations could be performed using provided BPF token.
This is achieved through mounting BPF FS instance with extra delegation
mount options, which determine what operations are delegatable, and also
constraining it to the owning user namespace (as mentioned in the
previous patch).
BPF token itself is just a derivative from BPF FS and can be created
through a new bpf() syscall command, BPF_TOKEN_CREATE, which accepts BPF
FS FD, which can be attained through open() API by opening BPF FS mount
point. Currently, BPF token "inherits" delegated command, map types,
prog type, and attach type bit sets from BPF FS as is. In the future,
having an BPF token as a separate object with its own FD, we can allow
to further restrict BPF token's allowable set of things either at the
creation time or after the fact, allowing the process to guard itself
further from unintentionally trying to load undesired kind of BPF
programs. But for now we keep things simple and just copy bit sets as is.
When BPF token is created from BPF FS mount, we take reference to the
BPF super block's owning user namespace, and then use that namespace for
checking all the {CAP_BPF, CAP_PERFMON, CAP_NET_ADMIN, CAP_SYS_ADMIN}
capabilities that are normally only checked against init userns (using
capable()), but now we check them using ns_capable() instead (if BPF
token is provided). See bpf_token_capable() for details.
Such setup means that BPF token in itself is not sufficient to grant BPF
functionality. User namespaced process has to *also* have necessary
combination of capabilities inside that user namespace. So while
previously CAP_BPF was useless when granted within user namespace, now
it gains a meaning and allows container managers and sys admins to have
a flexible control over which processes can and need to use BPF
functionality within the user namespace (i.e., container in practice).
And BPF FS delegation mount options and derived BPF tokens serve as
a per-container "flag" to grant overall ability to use bpf() (plus further
restrict on which parts of bpf() syscalls are treated as namespaced).
Note also, BPF_TOKEN_CREATE command itself requires ns_capable(CAP_BPF)
within the BPF FS owning user namespace, rounding up the ns_capable()
story of BPF token. Also creating BPF token in init user namespace is
currently not supported, given BPF token doesn't have any effect in init
user namespace anyways.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/bpf/20240124022127.2379740-4-andrii@kernel.org
|