Commit Graph

4134 Commits (09cfd3c52ea76f43b3cb15e570aeddf633d65e80)

Author SHA1 Message Date
Daniel Borkmann f9bb6ffa7f bpf: Fix out-of-bounds dynptr write in bpf_crypto_crypt
Stanislav reported that in bpf_crypto_crypt() the destination dynptr's
size is not validated to be at least as large as the source dynptr's
size before calling into the crypto backend with 'len = src_len'. This
can result in an OOB write when the destination is smaller than the
source.

Concretely, in mentioned function, psrc and pdst are both linear
buffers fetched from each dynptr:

  psrc = __bpf_dynptr_data(src, src_len);
  [...]
  pdst = __bpf_dynptr_data_rw(dst, dst_len);
  [...]
  err = decrypt ?
        ctx->type->decrypt(ctx->tfm, psrc, pdst, src_len, piv) :
        ctx->type->encrypt(ctx->tfm, psrc, pdst, src_len, piv);

The crypto backend expects pdst to be large enough with a src_len length
that can be written. Add an additional src_len > dst_len check and bail
out if it's the case. Note that these kfuncs are accessible under root
privileges only.

Fixes: 3e1c6f3540 ("bpf: make common crypto API for TC/XDP programs")
Reported-by: Stanislav Fort <disclosure@aisle.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Link: https://lore.kernel.org/r/20250829143657.318524-1-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-09-09 15:07:57 -07:00
Marco Crivellari a857210b10 bpf: WQ_PERCPU added to alloc_workqueue users
Currently if a user enqueue a work item using schedule_delayed_work() the
used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use
WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to
schedule_work() that is using system_wq and queue_work(), that makes use
again of WORK_CPU_UNBOUND.
This lack of consistentcy cannot be addressed without refactoring the API.

alloc_workqueue() treats all queues as per-CPU by default, while unbound
workqueues must opt-in via WQ_UNBOUND.

This default is suboptimal: most workloads benefit from unbound queues,
allowing the scheduler to place worker threads where they’re needed and
reducing noise when CPUs are isolated.

This default is suboptimal: most workloads benefit from unbound queues,
allowing the scheduler to place worker threads where they’re needed and
reducing noise when CPUs are isolated.

This patch adds a new WQ_PERCPU flag to explicitly request the use of
the per-CPU behavior. Both flags coexist for one release cycle to allow
callers to transition their calls.

Once migration is complete, WQ_UNBOUND can be removed and unbound will
become the implicit default.

With the introduction of the WQ_PERCPU flag (equivalent to !WQ_UNBOUND),
any alloc_workqueue() caller that doesn’t explicitly specify WQ_UNBOUND
must now use WQ_PERCPU.

All existing users have been updated accordingly.

Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Marco Crivellari <marco.crivellari@suse.com>
Link: https://lore.kernel.org/r/20250905085309.94596-4-marco.crivellari@suse.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-09-08 10:04:37 -07:00
Marco Crivellari 0409819a00 bpf: replace use of system_unbound_wq with system_dfl_wq
Currently if a user enqueue a work item using schedule_delayed_work() the
used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use
WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to
schedule_work() that is using system_wq and queue_work(), that makes use
again of WORK_CPU_UNBOUND.

This lack of consistentcy cannot be addressed without refactoring the API.

system_unbound_wq should be the default workqueue so as not to enforce
locality constraints for random work whenever it's not required.

Adding system_dfl_wq to encourage its use when unbound work should be used.

queue_work() / queue_delayed_work() / mod_delayed_work() will now use the
new unbound wq: whether the user still use the old wq a warn will be
printed along with a wq redirect to the new one.

The old system_unbound_wq will be kept for a few release cycles.

Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Marco Crivellari <marco.crivellari@suse.com>
Link: https://lore.kernel.org/r/20250905085309.94596-3-marco.crivellari@suse.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-09-08 10:04:37 -07:00
Marco Crivellari 34f86083a4 bpf: replace use of system_wq with system_percpu_wq
Currently if a user enqueue a work item using schedule_delayed_work() the
used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use
WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to
schedule_work() that is using system_wq and queue_work(), that makes use
again of WORK_CPU_UNBOUND.

This lack of consistentcy cannot be addressed without refactoring the API.

system_wq is a per-CPU worqueue, yet nothing in its name tells about that
CPU affinity constraint, which is very often not required by users. Make
it clear by adding a system_percpu_wq.

queue_work() / queue_delayed_work() mod_delayed_work() will now use the
new per-cpu wq: whether the user still stick on the old name a warn will
be printed along a wq redirect to the new one.

This patch add the new system_percpu_wq except for mm, fs and net
subsystem, whom are handled in separated patches.

The old wq will be kept for a few release cylces.

Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Marco Crivellari <marco.crivellari@suse.com>
Link: https://lore.kernel.org/r/20250905085309.94596-2-marco.crivellari@suse.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-09-08 10:04:37 -07:00
Rong Tao 19559e8441 bpf: add bpf_strcasecmp kfunc
bpf_strcasecmp() function performs same like bpf_strcmp() except ignoring
the case of the characters.

Signed-off-by: Rong Tao <rongtao@cestc.cn>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Acked-by: Viktor Malik <vmalik@redhat.com>
Link: https://lore.kernel.org/r/tencent_292BD3682A628581AA904996D8E59F4ACD06@qq.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-09-04 09:00:57 -07:00
Feng Yang e4980fa646 bpf: Replace kvfree with kfree for kzalloc memory
These pointers are allocated by kzalloc. Therefore, replace kvfree() with
kfree() to avoid unnecessary is_vmalloc_addr() check in kvfree(). This is
the remaining unmodified part from [1].

Signed-off-by: Feng Yang <yangfeng@kylinos.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20250811123949.552885-1-rongqianfeng@vivo.com [1]
Link: https://lore.kernel.org/bpf/20250827032812.498216-1-yangfeng59949@163.com
2025-09-02 17:29:52 +02:00
Nandakumar Edamana 1df7dad4d5 bpf: Improve the general precision of tnum_mul
Drop the value-mask decomposition technique and adopt straightforward
long-multiplication with a twist: when LSB(a) is uncertain, find the
two partial products (for LSB(a) = known 0 and LSB(a) = known 1) and
take a union.

Experiment shows that applying this technique in long multiplication
improves the precision in a significant number of cases (at the cost
of losing precision in a relatively lower number of cases).

Signed-off-by: Nandakumar Edamana <nandakumar@nandakumar.co.in>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Harishankar Vishwanathan <harishankar.vishwanathan@gmail.com>
Reviewed-by: Harishankar Vishwanathan <harishankar.vishwanathan@gmail.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20250826034524.2159515-1-nandakumar@nandakumar.co.in
2025-08-27 15:00:26 -07:00
Josh Poimboeuf e649bcda25 perf: Remove get_perf_callchain() init_nr argument
The 'init_nr' argument has double duty: it's used to initialize both the
number of contexts and the number of stack entries.  That's confusing
and the callers always pass zero anyway.  Hard code the zero.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Namhyung Kim <Namhyung@kernel.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/r/20250820180428.259565081@kernel.org
2025-08-26 09:51:12 +02:00
Menglong Dong 8e4f0b1ebc bpf: use rcu_read_lock_dont_migrate() for trampoline.c
Use rcu_read_lock_dont_migrate() and rcu_read_unlock_migrate() in
trampoline.c to obtain better performance when PREEMPT_RCU is not enabled.

Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn>
Link: https://lore.kernel.org/r/20250821090609.42508-8-dongml2@chinatelecom.cn
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-08-25 18:52:16 -07:00
Menglong Dong 427a36bb55 bpf: use rcu_read_lock_dont_migrate() for bpf_prog_run_array_cg()
Use rcu_read_lock_dont_migrate() and rcu_read_unlock_migrate() in
bpf_prog_run_array_cg to obtain better performance when PREEMPT_RCU is
not enabled.

Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn>
Link: https://lore.kernel.org/r/20250821090609.42508-7-dongml2@chinatelecom.cn
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-08-25 18:52:16 -07:00
Menglong Dong cf4303b70d bpf: use rcu_read_lock_dont_migrate() for bpf_task_storage_free()
Use rcu_read_lock_dont_migrate() and rcu_read_unlock_migrate() in
bpf_task_storage_free to obtain better performance when PREEMPT_RCU is
not enabled.

Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn>
Link: https://lore.kernel.org/r/20250821090609.42508-6-dongml2@chinatelecom.cn
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-08-25 18:52:16 -07:00
Menglong Dong 68748f0397 bpf: use rcu_read_lock_dont_migrate() for bpf_iter_run_prog()
Use rcu_read_lock_dont_migrate() and rcu_read_unlock_migrate() in
bpf_iter_run_prog to obtain better performance when PREEMPT_RCU is
not enabled.

Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn>
Link: https://lore.kernel.org/r/20250821090609.42508-5-dongml2@chinatelecom.cn
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-08-25 18:52:16 -07:00
Menglong Dong f2fa9b9069 bpf: use rcu_read_lock_dont_migrate() for bpf_inode_storage_free()
Use rcu_read_lock_dont_migrate() and rcu_read_unlock_migrate() in
bpf_inode_storage_free to obtain better performance when PREEMPT_RCU is
not enabled.

Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn>
Link: https://lore.kernel.org/r/20250821090609.42508-4-dongml2@chinatelecom.cn
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-08-25 18:52:16 -07:00
Menglong Dong 8c0afc7c9c bpf: use rcu_read_lock_dont_migrate() for bpf_cgrp_storage_free()
Use rcu_read_lock_dont_migrate() and rcu_read_unlock_migrate() in
bpf_cgrp_storage_free to obtain better performance when PREEMPT_RCU is
not enabled.

Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn>
Link: https://lore.kernel.org/r/20250821090609.42508-3-dongml2@chinatelecom.cn
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-08-25 18:52:16 -07:00
Tao Chen 4223bf833c bpf: Remove preempt_disable in bpf_try_get_buffers
Now BPF program will run with migration disabled, so it is safe
to access this_cpu_inc_return(bpf_bprintf_nest_level).

Fixes: d9c9e4db18 ("bpf: Factorize bpf_trace_printk and bpf_seq_printf")
Signed-off-by: Tao Chen <chen.dylane@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250819125638.2544715-1-chen.dylane@linux.dev
2025-08-22 11:44:09 -07:00
Eric Biggers d47cc4dea1 bpf: Use sha1() instead of sha1_transform() in bpf_prog_calc_tag()
Now that there's a proper SHA-1 library API, just use that instead of
the low-level SHA-1 compression function.  This eliminates the need for
bpf_prog_calc_tag() to implement the SHA-1 padding itself.  No
functional change; the computed tags remain the same.

Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20250811201615.564461-1-ebiggers@kernel.org
2025-08-22 11:40:05 -07:00
Paul Chaignon f41345f47f bpf: Use tnums for JEQ/JNE is_branch_taken logic
In the following toy program (reg states minimized for readability), R0
and R1 always have different values at instruction 6. This is obvious
when reading the program but cannot be guessed from ranges alone as
they overlap (R0 in [0; 0xc0000000], R1 in [1024; 0xc0000400]).

  0: call bpf_get_prandom_u32#7  ; R0_w=scalar()
  1: w0 = w0                     ; R0_w=scalar(var_off=(0x0; 0xffffffff))
  2: r0 >>= 30                   ; R0_w=scalar(var_off=(0x0; 0x3))
  3: r0 <<= 30                   ; R0_w=scalar(var_off=(0x0; 0xc0000000))
  4: r1 = r0                     ; R1_w=scalar(var_off=(0x0; 0xc0000000))
  5: r1 += 1024                  ; R1_w=scalar(var_off=(0x400; 0xc0000000))
  6: if r1 != r0 goto pc+1

Looking at tnums however, we can deduce that R1 is always different from
R0 because their tnums don't agree on known bits. This patch uses this
logic to improve is_scalar_branch_taken in case of BPF_JEQ and BPF_JNE.

This change has a tiny impact on complexity, which was measured with
the Cilium complexity CI test. That test covers 72 programs with
various build and load time configurations for a total of 970 test
cases. For 80% of test cases, the patch has no impact. On the other
test cases, the patch decreases complexity by only 0.08% on average. In
the best case, the verifier needs to walk 3% less instructions and, in
the worst case, 1.5% more. Overall, the patch has a small positive
impact, especially for our largest programs.

Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/be3ee70b6e489c49881cb1646114b1d861b5c334.1755694147.git.paul.chaignon@gmail.com
2025-08-22 18:12:24 +02:00
Martin KaFai Lau 5c42715e63 Merge branch 'bpf-next/skb-meta-dynptr' into 'bpf-next/master'
Merge 'skb-meta-dynptr' branch into 'master' branch. No conflict.

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2025-08-18 17:59:26 -07:00
Jakub Sitnicki 6877cd392b bpf: Enable read/write access to skb metadata through a dynptr
Now that we can create a dynptr to skb metadata, make reads to the metadata
area possible with bpf_dynptr_read() or through a bpf_dynptr_slice(), and
make writes to the metadata area possible with bpf_dynptr_write() or
through a bpf_dynptr_slice_rdwr().

Note that for cloned skbs which share data with the original, we limit the
skb metadata dynptr to be read-only since we don't unclone on a
bpf_dynptr_write to metadata.

Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20250814-skb-metadata-thru-dynptr-v7-2-8a39e636e0fb@cloudflare.com
2025-08-18 10:29:42 -07:00
Jakub Sitnicki 89d912e494 bpf: Add dynptr type for skb metadata
Add a dynptr type, similar to skb dynptr, but for the skb metadata access.

The dynptr provides an alternative to __sk_buff->data_meta for accessing
the custom metadata area allocated using the bpf_xdp_adjust_meta() helper.

More importantly, it abstracts away the fact where the storage for the
custom metadata lives, which opens up the way to persist the metadata by
relocating it as the skb travels through the network stack layers.

Writes to skb metadata invalidate any existing skb payload and metadata
slices. While this is more restrictive that needed at the moment, it leaves
the door open to reallocating the metadata on writes, and should be only a
minor inconvenience to the users.

Only the program types which can access __sk_buff->data_meta today are
allowed to create a dynptr for skb metadata at the moment. We need to
modify the network stack to persist the metadata across layers before
opening up access to other BPF hooks.

Once more BPF hooks gain access to skb_meta dynptr, we will also need to
add a read-only variant of the helper similar to
bpf_dynptr_from_skb_rdonly.

skb_meta dynptr ops are stubbed out and implemented by subsequent changes.

Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: Jesse Brandeburg <jbrandeburg@cloudflare.com>
Link: https://patch.msgid.link/20250814-skb-metadata-thru-dynptr-v7-1-8a39e636e0fb@cloudflare.com
2025-08-18 10:29:42 -07:00
Anton Protopopov dbe99ea541 bpf: Add a verbose message when the BTF limit is reached
When a BPF program which is being loaded reaches the map limit
(MAX_USED_MAPS) or the BTF limit (MAX_USED_BTFS) the -E2BIG is
returned. However, in the former case there is an accompanying
verifier verbose message, and in the latter case there is not.
Add a verbose message to make the behaviour symmetrical.

Reported-by: Kevin Sheldrake <kevin.sheldrake@isovalent.com>
Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20250816151554.902995-1-a.s.protopopov@gmail.com
2025-08-18 17:27:01 +02:00
Fushuai Wang d87fdb1f27 bpf: Replace get_next_cpu() with cpumask_next_wrap()
The get_next_cpu() function was only used in one place to find
the next possible CPU, which can be replaced by cpumask_next_wrap().

Signed-off-by: Fushuai Wang <wangfushuai@baidu.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20250818032344.23229-1-wangfushuai@baidu.com
2025-08-18 15:11:02 +02:00
Jiri Olsa e4414b01c1 bpf: Check the helper function is valid in get_helper_proto
kernel test robot reported verifier bug [1] where the helper func
pointer could be NULL due to disabled config option.

As Alexei suggested we could check on that in get_helper_proto
directly. Marking tail_call helper func with BPF_PTR_POISON,
because it is unused by design.

  [1] https://lore.kernel.org/oe-lkp/202507160818.68358831-lkp@intel.com

Reported-by: kernel test robot <oliver.sang@intel.com>
Reported-by: syzbot+a9ed3d9132939852d0df@syzkaller.appspotmail.com
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Paul Chaignon <paul.chaignon@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20250814200655.945632-1-jolsa@kernel.org
Closes: https://lore.kernel.org/oe-lkp/202507160818.68358831-lkp@intel.com
2025-08-15 11:16:56 +02:00
Jesper Dangaard Brouer 2b986b9e91 bpf, cpumap: Disable page_pool direct xdp_return need larger scope
When running an XDP bpf_prog on the remote CPU in cpumap code
then we must disable the direct return optimization that
xdp_return can perform for mem_type page_pool.  This optimization
assumes code is still executing under RX-NAPI of the original
receiving CPU, which isn't true on this remote CPU.

The cpumap code already disabled this via helpers
xdp_set_return_frame_no_direct() and xdp_clear_return_frame_no_direct(),
but the scope didn't include xdp_do_flush().

When doing XDP_REDIRECT towards e.g devmap this causes the
function bq_xmit_all() to run with direct return optimization
enabled. This can lead to hard to find bugs.  The issue
only happens when bq_xmit_all() cannot ndo_xdp_xmit all
frames and them frees them via xdp_return_frame_rx_napi().

Fix by expanding scope to include xdp_do_flush(). This was found
by Dragos Tatulea.

Fixes: 11941f8a85 ("bpf: cpumap: Implement generic cpumap")
Reported-by: Dragos Tatulea <dtatulea@nvidia.com>
Reported-by: Chris Arges <carges@cloudflare.com>
Signed-off-by: Jesper Dangaard Brouer <hawk@kernel.org>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Chris Arges <carges@cloudflare.com>
Link: https://patch.msgid.link/175519587755.3008742.1088294435150406835.stgit@firesoul
2025-08-15 11:08:08 +02:00
Qianfeng Rong bf0c2a84df bpf: Replace kvfree with kfree for kzalloc memory
The 'backedge' pointer is allocated with kzalloc(), which returns
physically contiguous memory. Using kvfree() to deallocate such
memory is functionally safe but semantically incorrect.

Replace kvfree() with kfree() to avoid unnecessary is_vmalloc_addr()
check in kvfree().

Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20250811123949.552885-1-rongqianfeng@vivo.com
2025-08-12 15:55:01 -07:00
Qianfeng Rong 3e2b799008 bpf: Remove redundant __GFP_NOWARN
Commit 16f5dfbc85 ("gfp: include __GFP_NOWARN in GFP_NOWAIT")
made GFP_NOWAIT implicitly include __GFP_NOWARN.

Therefore, explicit __GFP_NOWARN combined with GFP_NOWAIT
(e.g., `GFP_NOWAIT | __GFP_NOWARN`) is now redundant. Let's clean
up these redundant flags across subsystems.

No functional changes.

Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20250804122731.460158-1-rongqianfeng@vivo.com
2025-08-12 14:56:04 -07:00
Martin KaFai Lau 9e293d47bf Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Cross merge bpf/master after 6.17-rc1.

No conflict.

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2025-08-12 12:14:02 -07:00
Eduard Zingerman 77620d1267 bpf: use realloc in bpf_patch_insn_data
Avoid excessive vzalloc/vfree calls when patching instructions in
do_misc_fixups(). bpf_patch_insn_data() uses vzalloc to allocate new
memory for env->insn_aux_data for each patch as follows:

  struct bpf_prog *bpf_patch_insn_data(env, ...)
  {
    ...
    new_data = vzalloc(... O(program size) ...);
    ...
    adjust_insn_aux_data(env, new_data, ...);
    ...
  }

  void adjust_insn_aux_data(env, new_data, ...)
  {
    ...
    memcpy(new_data, env->insn_aux_data);
    vfree(env->insn_aux_data);
    env->insn_aux_data = new_data;
    ...
  }

The vzalloc/vfree pair is hot in perf report collected for e.g.
pyperf180 test case. It can be replaced with a call to vrealloc in
order to reduce the number of actual memory allocations.

This is a stop-gap solution, as bpf_patch_insn_data is still hot in
the profile. More comprehansive solutions had been discussed before
e.g. as in [1].

[1] https://lore.kernel.org/bpf/CAEf4BzY_E8MSL4mD0UPuuiDcbJhh9e2xQo2=5w+ppRWWiYSGvQ@mail.gmail.com/

Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Tested-by: Anton Protopopov <a.s.protopopov@gmail.com>
Link: https://lore.kernel.org/r/20250807010205.3210608-3-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-08-07 09:17:02 -07:00
Eduard Zingerman cb070a8156 bpf: removed unused 'env' parameter from is_reg64 and insn_has_def32
Parameter 'env' is not used by is_reg64() and insn_has_def32()
functions. Remove the parameter to make it clear that neither function
depends on 'env' state, e.g. env->insn_aux_data.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20250807010205.3210608-2-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-08-07 09:17:02 -07:00
Amery Hung d87a513d09 bpf: Allow struct_ops to get map id by kdata
Add bpf_struct_ops_id() to enable struct_ops implementors to use
struct_ops map id as the unique id of a struct_ops in their subsystem.
A subsystem that wishes to create a mapping between id and struct_ops
instance pointer can update the mapping accordingly during
bpf_struct_ops::reg(), unreg(), and update().

Signed-off-by: Amery Hung <ameryhung@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20250806162540.681679-2-ameryhung@gmail.com
2025-08-06 13:39:58 -07:00
Eduard Zingerman 1b30d44417 bpf: Fix memory leak of bpf_scc_info objects
env->scc_info array contains references to bpf_scc_info objects
allocated lazily in verifier.c:scc_visit_alloc().
env->scc_cnt was supposed to track env->scc_info array size
in order to free referenced objects in verifier.c:free_states().
Fix initialization of env->scc_cnt that was omitted in
verifier.c:compute_scc().

To reproduce the bug:
- build with CONFIG_DEBUG_KMEMLEAK
- boot and load bpf program with loops, e.g.:
  ./veristat -q pyperf180.bpf.o
- initiate memleak scan and check results:
  echo scan > /sys/kernel/debug/kmemleak
  cat /sys/kernel/debug/kmemleak

Fixes: c9e31900b5 ("bpf: propagate read/precision marks over state graph backedges")
Reported-by: Jens Axboe <axboe@kernel.dk>
Closes: https://lore.kernel.org/bpf/CAADnVQKXUWg9uRCPD5ebRXwN4dmBCRUFFM7kN=GxymYz3zU25A@mail.gmail.com/T/
Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Tested-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250801232330.1800436-1-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-08-02 09:04:57 -07:00
Paul Chaignon f914876eec bpf: Improve ctx access verifier error message
We've already had two "error during ctx access conversion" warnings
triggered by syzkaller. Let's improve the error message by dumping the
cnt variable so that we can more easily differentiate between the
different error cases.

Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/cc94316c30dd76fae4a75a664b61a2dbfe68e205.1754039605.git.paul.chaignon@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-08-01 09:22:44 -07:00
Daniel Borkmann abad3d0bad bpf: Fix oob access in cgroup local storage
Lonial reported that an out-of-bounds access in cgroup local storage
can be crafted via tail calls. Given two programs each utilizing a
cgroup local storage with a different value size, and one program
doing a tail call into the other. The verifier will validate each of
the indivial programs just fine. However, in the runtime context
the bpf_cg_run_ctx holds an bpf_prog_array_item which contains the
BPF program as well as any cgroup local storage flavor the program
uses. Helpers such as bpf_get_local_storage() pick this up from the
runtime context:

  ctx = container_of(current->bpf_ctx, struct bpf_cg_run_ctx, run_ctx);
  storage = ctx->prog_item->cgroup_storage[stype];

  if (stype == BPF_CGROUP_STORAGE_SHARED)
    ptr = &READ_ONCE(storage->buf)->data[0];
  else
    ptr = this_cpu_ptr(storage->percpu_buf);

For the second program which was called from the originally attached
one, this means bpf_get_local_storage() will pick up the former
program's map, not its own. With mismatching sizes, this can result
in an unintended out-of-bounds access.

To fix this issue, we need to extend bpf_map_owner with an array of
storage_cookie[] to match on i) the exact maps from the original
program if the second program was using bpf_get_local_storage(), or
ii) allow the tail call combination if the second program was not
using any of the cgroup local storage maps.

Fixes: 7d9c342789 ("bpf: Make cgroup storages shared between programs on the same cgroup")
Reported-by: Lonial Con <kongln9170@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20250730234733.530041-4-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-31 11:30:05 -07:00
Daniel Borkmann fd1c98f0ef bpf: Move bpf map owner out of common struct
Given this is only relevant for BPF tail call maps, it is adding up space
and penalizing other map types. We also need to extend this with further
objects to track / compare to. Therefore, lets move this out into a separate
structure and dynamically allocate it only for BPF tail call maps.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20250730234733.530041-2-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-31 11:30:05 -07:00
Daniel Borkmann 12df58ad29 bpf: Add cookie object to bpf maps
Add a cookie to BPF maps to uniquely identify BPF maps for the timespan
when the node is up. This is different to comparing a pointer or BPF map
id which could get rolled over and reused.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20250730234733.530041-1-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-31 11:30:05 -07:00
Linus Torvalds d9104cec3e bpf-next-6.17
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Merge tag 'bpf-next-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Pull bpf updates from Alexei Starovoitov:

 - Remove usermode driver (UMD) framework (Thomas Weißschuh)

 - Introduce Strongly Connected Component (SCC) in the verifier to
   detect loops and refine register liveness (Eduard Zingerman)

 - Allow 'void *' cast using bpf_rdonly_cast() and corresponding
   '__arg_untrusted' for global function parameters (Eduard Zingerman)

 - Improve precision for BPF_ADD and BPF_SUB operations in the verifier
   (Harishankar Vishwanathan)

 - Teach the verifier that constant pointer to a map cannot be NULL
   (Ihor Solodrai)

 - Introduce BPF streams for error reporting of various conditions
   detected by BPF runtime (Kumar Kartikeya Dwivedi)

 - Teach the verifier to insert runtime speculation barrier (lfence on
   x86) to mitigate speculative execution instead of rejecting the
   programs (Luis Gerhorst)

 - Various improvements for 'veristat' (Mykyta Yatsenko)

 - For CONFIG_DEBUG_KERNEL config warn on internal verifier errors to
   improve bug detection by syzbot (Paul Chaignon)

 - Support BPF private stack on arm64 (Puranjay Mohan)

 - Introduce bpf_cgroup_read_xattr() kfunc to read xattr of cgroup's
   node (Song Liu)

 - Introduce kfuncs for read-only string opreations (Viktor Malik)

 - Implement show_fdinfo() for bpf_links (Tao Chen)

 - Reduce verifier's stack consumption (Yonghong Song)

 - Implement mprog API for cgroup-bpf programs (Yonghong Song)

* tag 'bpf-next-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (192 commits)
  selftests/bpf: Migrate fexit_noreturns case into tracing_failure test suite
  selftests/bpf: Add selftest for attaching tracing programs to functions in deny list
  bpf: Add log for attaching tracing programs to functions in deny list
  bpf: Show precise rejected function when attaching fexit/fmod_ret to __noreturn functions
  bpf: Fix various typos in verifier.c comments
  bpf: Add third round of bounds deduction
  selftests/bpf: Test invariants on JSLT crossing sign
  selftests/bpf: Test cross-sign 64bits range refinement
  selftests/bpf: Update reg_bound range refinement logic
  bpf: Improve bounds when s64 crosses sign boundary
  bpf: Simplify bounds refinement from s32
  selftests/bpf: Enable private stack tests for arm64
  bpf, arm64: JIT support for private stack
  bpf: Move bpf_jit_get_prog_name() to core.c
  bpf, arm64: Fix fp initialization for exception boundary
  umd: Remove usermode driver framework
  bpf/preload: Don't select USERMODE_DRIVER
  selftests/bpf: Fix test dynptr/test_dynptr_memset_xdp_chunks failure
  selftests/bpf: Fix test dynptr/test_dynptr_copy_xdp failure
  selftests/bpf: Increase xdp data size for arm64 64K page size
  ...
2025-07-30 09:58:50 -07:00
Linus Torvalds 8be4d31cb8 Networking changes for 6.17.
Core & protocols
 ----------------
 
  - Wrap datapath globals into net_aligned_data, to avoid false sharing.
 
  - Preserve MSG_ZEROCOPY in forwarding (e.g. out of a container).
 
  - Add SO_INQ and SCM_INQ support to AF_UNIX.
 
  - Add SIOCINQ support to AF_VSOCK.
 
  - Add TCP_MAXSEG sockopt to MPTCP.
 
  - Add IPv6 force_forwarding sysctl to enable forwarding per interface.
 
  - Make TCP validation of whether packet fully fits in the receive
    window and the rcv_buf more strict. With increased use of HW
    aggregation a single "packet" can be multiple 100s of kB.
 
  - Add MSG_MORE flag to optimize large TCP transmissions via sockmap,
    improves latency up to 33% for sockmap users.
 
  - Convert TCP send queue handling from tasklet to BH workque.
 
  - Improve BPF iteration over TCP sockets to see each socket exactly once.
 
  - Remove obsolete and unused TCP RFC3517/RFC6675 loss recovery code.
 
  - Support enabling kernel threads for NAPI processing on per-NAPI
    instance basis rather than a whole device. Fully stop the kernel NAPI
    thread when threaded NAPI gets disabled. Previously thread would stick
    around until ifdown due to tricky synchronization.
 
  - Allow multicast routing to take effect on locally-generated packets.
 
  - Add output interface argument for End.X in segment routing.
 
  - MCTP: add support for gateway routing, improve bind() handling.
 
  - Don't require rtnl_lock when fetching an IPv6 neighbor over Netlink.
 
  - Add a new neighbor flag ("extern_valid"), which cedes refresh
    responsibilities to userspace. This is needed for EVPN multi-homing
    where a neighbor entry for a multi-homed host needs to be synced
    across all the VTEPs among which the host is multi-homed.
 
  - Support NUD_PERMANENT for proxy neighbor entries.
 
  - Add a new queuing discipline for IETF RFC9332 DualQ Coupled AQM.
 
  - Add sequence numbers to netconsole messages. Unregister netconsole's
    console when all net targets are removed. Code refactoring.
    Add a number of selftests.
 
  - Align IPSec inbound SA lookup to RFC 4301. Only SPI and protocol
    should be used for an inbound SA lookup.
 
  - Support inspecting ref_tracker state via DebugFS.
 
  - Don't force bonding advertisement frames tx to ~333 ms boundaries.
    Add broadcast_neighbor option to send ARP/ND on all bonded links.
 
  - Allow providing upcall pid for the 'execute' command in openvswitch.
 
  - Remove DCCP support from Netfilter's conntrack.
 
  - Disallow multiple packet duplications in the queuing layer.
 
  - Prevent use of deprecated iptables code on PREEMPT_RT.
 
 Driver API
 ----------
 
  - Support RSS and hashing configuration over ethtool Netlink.
 
  - Add dedicated ethtool callbacks for getting and setting hashing fields.
 
  - Add support for power budget evaluation strategy in PSE /
    Power-over-Ethernet. Generate Netlink events for overcurrent etc.
 
  - Support DPLL phase offset monitoring across all device inputs.
    Support providing clock reference and SYNC over separate DPLL
    inputs.
 
  - Support traffic classes in devlink rate API for bandwidth management.
 
  - Remove rtnl_lock dependency from UDP tunnel port configuration.
 
 Device drivers
 --------------
 
  - Add a new Broadcom driver for 800G Ethernet (bnge).
 
  - Add a standalone driver for Microchip ZL3073x DPLL.
 
  - Remove IBM's NETIUCV device driver.
 
  - Ethernet high-speed NICs:
    - Broadcom (bnxt):
     - support zero-copy Tx of DMABUF memory
     - take page size into account for page pool recycling rings
    - Intel (100G, ice, idpf):
      - idpf: XDP and AF_XDP support preparations
      - idpf: add flow steering
      - add link_down_events statistic
      - clean up the TSPLL code
      - preparations for live VM migration
    - nVidia/Mellanox:
     - support zero-copy Rx/Tx interfaces (DMABUF and io_uring)
     - optimize context memory usage for matchers
     - expose serial numbers in devlink info
     - support PCIe congestion metrics
    - Meta (fbnic):
      - add 25G, 50G, and 100G link modes to phylink
      - support dumping FW logs
    - Marvell/Cavium:
      - support for CN20K generation of the Octeon chips
    - Amazon:
      - add HW clock (without timestamping, just hypervisor time access)
 
  - Ethernet virtual:
    - VirtIO net:
      - support segmentation of UDP-tunnel-encapsulated packets
    - Google (gve):
      - support packet timestamping and clock synchronization
    - Microsoft vNIC:
      - add handler for device-originated servicing events
      - allow dynamic MSI-X vector allocation
      - support Tx bandwidth clamping
 
  - Ethernet NICs consumer, and embedded:
    - AMD:
      - amd-xgbe: hardware timestamping and PTP clock support
    - Broadcom integrated MACs (bcmgenet, bcmasp):
      - use napi_complete_done() return value to support NAPI polling
      - add support for re-starting auto-negotiation
    - Broadcom switches (b53):
      - support BCM5325 switches
      - add bcm63xx EPHY power control
    - Synopsys (stmmac):
      - lots of code refactoring and cleanups
    - TI:
      - icssg-prueth: read firmware-names from device tree
      - icssg: PRP offload support
    - Microchip:
      - lan78xx: convert to PHYLINK for improved PHY and MAC management
      - ksz: add KSZ8463 switch support
    - Intel:
      - support similar queue priority scheme in multi-queue and
        time-sensitive networking (taprio)
      - support packet pre-emption in both
    - RealTek (r8169):
      - enable EEE at 5Gbps on RTL8126
    - Airoha:
      - add PPPoE offload support
      - MDIO bus controller for Airoha AN7583
 
  - Ethernet PHYs:
    - support for the IPQ5018 internal GE PHY
    - micrel KSZ9477 switch-integrated PHYs:
      - add MDI/MDI-X control support
      - add RX error counters
      - add cable test support
      - add Signal Quality Indicator (SQI) reporting
    - dp83tg720: improve reset handling and reduce link recovery time
    - support bcm54811 (and its MII-Lite interface type)
    - air_en8811h: support resume/suspend
    - support PHY counters for QCA807x and QCA808x
    - support WoL for QCA807x
 
  - CAN drivers:
    - rcar_canfd: support for Transceiver Delay Compensation
    - kvaser: report FW versions via devlink dev info
 
  - WiFi:
    - extended regulatory info support (6 GHz)
    - add statistics and beacon monitor for Multi-Link Operation (MLO)
    - support S1G aggregation, improve S1G support
    - add Radio Measurement action fields
    - support per-radio RTS threshold
    - some work around how FIPS affects wifi, which was wrong (RC4 is used
      by TKIP, not only WEP)
    - improvements for unsolicited probe response handling
 
  - WiFi drivers:
    - RealTek (rtw88):
      - IBSS mode for SDIO devices
    - RealTek (rtw89):
      - BT coexistence for MLO/WiFi7
      - concurrent station + P2P support
      - support for USB devices RTL8851BU/RTL8852BU
    - Intel (iwlwifi):
      - use embedded PNVM in (to be released) FW images to fix
        compatibility issues
      - many cleanups (unused FW APIs, PCIe code, WoWLAN)
      - some FIPS interoperability
    - MediaTek (mt76):
      - firmware recovery improvements
      - more MLO work
    - Qualcomm/Atheros (ath12k):
      - fix scan on multi-radio devices
      - more EHT/Wi-Fi 7 features
      - encapsulation/decapsulation offload
    - Broadcom (brcm80211):
      - support SDIO 43751 device
 
  - Bluetooth:
    - hci_event: add support for handling LE BIG Sync Lost event
    - ISO: add socket option to report packet seqnum via CMSG
    - ISO: support SCM_TIMESTAMPING for ISO TS
 
  - Bluetooth drivers:
    - intel_pcie: support Function Level Reset
    - nxpuart: add support for 4M baudrate
    - nxpuart: implement powerup sequence, reset, FW dump, and FW loading
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-next-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking updates from Jakub Kicinski:
 "Core & protocols:

   - Wrap datapath globals into net_aligned_data, to avoid false sharing

   - Preserve MSG_ZEROCOPY in forwarding (e.g. out of a container)

   - Add SO_INQ and SCM_INQ support to AF_UNIX

   - Add SIOCINQ support to AF_VSOCK

   - Add TCP_MAXSEG sockopt to MPTCP

   - Add IPv6 force_forwarding sysctl to enable forwarding per interface

   - Make TCP validation of whether packet fully fits in the receive
     window and the rcv_buf more strict. With increased use of HW
     aggregation a single "packet" can be multiple 100s of kB

   - Add MSG_MORE flag to optimize large TCP transmissions via sockmap,
     improves latency up to 33% for sockmap users

   - Convert TCP send queue handling from tasklet to BH workque

   - Improve BPF iteration over TCP sockets to see each socket exactly
     once

   - Remove obsolete and unused TCP RFC3517/RFC6675 loss recovery code

   - Support enabling kernel threads for NAPI processing on per-NAPI
     instance basis rather than a whole device. Fully stop the kernel
     NAPI thread when threaded NAPI gets disabled. Previously thread
     would stick around until ifdown due to tricky synchronization

   - Allow multicast routing to take effect on locally-generated packets

   - Add output interface argument for End.X in segment routing

   - MCTP: add support for gateway routing, improve bind() handling

   - Don't require rtnl_lock when fetching an IPv6 neighbor over Netlink

   - Add a new neighbor flag ("extern_valid"), which cedes refresh
     responsibilities to userspace. This is needed for EVPN multi-homing
     where a neighbor entry for a multi-homed host needs to be synced
     across all the VTEPs among which the host is multi-homed

   - Support NUD_PERMANENT for proxy neighbor entries

   - Add a new queuing discipline for IETF RFC9332 DualQ Coupled AQM

   - Add sequence numbers to netconsole messages. Unregister
     netconsole's console when all net targets are removed. Code
     refactoring. Add a number of selftests

   - Align IPSec inbound SA lookup to RFC 4301. Only SPI and protocol
     should be used for an inbound SA lookup

   - Support inspecting ref_tracker state via DebugFS

   - Don't force bonding advertisement frames tx to ~333 ms boundaries.
     Add broadcast_neighbor option to send ARP/ND on all bonded links

   - Allow providing upcall pid for the 'execute' command in openvswitch

   - Remove DCCP support from Netfilter's conntrack

   - Disallow multiple packet duplications in the queuing layer

   - Prevent use of deprecated iptables code on PREEMPT_RT

  Driver API:

   - Support RSS and hashing configuration over ethtool Netlink

   - Add dedicated ethtool callbacks for getting and setting hashing
     fields

   - Add support for power budget evaluation strategy in PSE /
     Power-over-Ethernet. Generate Netlink events for overcurrent etc

   - Support DPLL phase offset monitoring across all device inputs.
     Support providing clock reference and SYNC over separate DPLL
     inputs

   - Support traffic classes in devlink rate API for bandwidth
     management

   - Remove rtnl_lock dependency from UDP tunnel port configuration

  Device drivers:

   - Add a new Broadcom driver for 800G Ethernet (bnge)

   - Add a standalone driver for Microchip ZL3073x DPLL

   - Remove IBM's NETIUCV device driver

   - Ethernet high-speed NICs:
      - Broadcom (bnxt):
         - support zero-copy Tx of DMABUF memory
         - take page size into account for page pool recycling rings
      - Intel (100G, ice, idpf):
         - idpf: XDP and AF_XDP support preparations
         - idpf: add flow steering
         - add link_down_events statistic
         - clean up the TSPLL code
         - preparations for live VM migration
      - nVidia/Mellanox:
         - support zero-copy Rx/Tx interfaces (DMABUF and io_uring)
         - optimize context memory usage for matchers
         - expose serial numbers in devlink info
         - support PCIe congestion metrics
      - Meta (fbnic):
         - add 25G, 50G, and 100G link modes to phylink
         - support dumping FW logs
      - Marvell/Cavium:
         - support for CN20K generation of the Octeon chips
      - Amazon:
         - add HW clock (without timestamping, just hypervisor time access)

   - Ethernet virtual:
      - VirtIO net:
         - support segmentation of UDP-tunnel-encapsulated packets
      - Google (gve):
         - support packet timestamping and clock synchronization
      - Microsoft vNIC:
         - add handler for device-originated servicing events
         - allow dynamic MSI-X vector allocation
         - support Tx bandwidth clamping

   - Ethernet NICs consumer, and embedded:
      - AMD:
         - amd-xgbe: hardware timestamping and PTP clock support
      - Broadcom integrated MACs (bcmgenet, bcmasp):
         - use napi_complete_done() return value to support NAPI polling
         - add support for re-starting auto-negotiation
      - Broadcom switches (b53):
         - support BCM5325 switches
         - add bcm63xx EPHY power control
      - Synopsys (stmmac):
         - lots of code refactoring and cleanups
      - TI:
         - icssg-prueth: read firmware-names from device tree
         - icssg: PRP offload support
      - Microchip:
         - lan78xx: convert to PHYLINK for improved PHY and MAC management
         - ksz: add KSZ8463 switch support
      - Intel:
         - support similar queue priority scheme in multi-queue and
           time-sensitive networking (taprio)
         - support packet pre-emption in both
      - RealTek (r8169):
         - enable EEE at 5Gbps on RTL8126
      - Airoha:
         - add PPPoE offload support
         - MDIO bus controller for Airoha AN7583

   - Ethernet PHYs:
      - support for the IPQ5018 internal GE PHY
      - micrel KSZ9477 switch-integrated PHYs:
         - add MDI/MDI-X control support
         - add RX error counters
         - add cable test support
         - add Signal Quality Indicator (SQI) reporting
      - dp83tg720: improve reset handling and reduce link recovery time
      - support bcm54811 (and its MII-Lite interface type)
      - air_en8811h: support resume/suspend
      - support PHY counters for QCA807x and QCA808x
      - support WoL for QCA807x

   - CAN drivers:
      - rcar_canfd: support for Transceiver Delay Compensation
      - kvaser: report FW versions via devlink dev info

   - WiFi:
      - extended regulatory info support (6 GHz)
      - add statistics and beacon monitor for Multi-Link Operation (MLO)
      - support S1G aggregation, improve S1G support
      - add Radio Measurement action fields
      - support per-radio RTS threshold
      - some work around how FIPS affects wifi, which was wrong (RC4 is
        used by TKIP, not only WEP)
      - improvements for unsolicited probe response handling

   - WiFi drivers:
      - RealTek (rtw88):
         - IBSS mode for SDIO devices
      - RealTek (rtw89):
         - BT coexistence for MLO/WiFi7
         - concurrent station + P2P support
         - support for USB devices RTL8851BU/RTL8852BU
      - Intel (iwlwifi):
         - use embedded PNVM in (to be released) FW images to fix
           compatibility issues
         - many cleanups (unused FW APIs, PCIe code, WoWLAN)
         - some FIPS interoperability
      - MediaTek (mt76):
         - firmware recovery improvements
         - more MLO work
      - Qualcomm/Atheros (ath12k):
         - fix scan on multi-radio devices
         - more EHT/Wi-Fi 7 features
         - encapsulation/decapsulation offload
      - Broadcom (brcm80211):
         - support SDIO 43751 device

   - Bluetooth:
      - hci_event: add support for handling LE BIG Sync Lost event
      - ISO: add socket option to report packet seqnum via CMSG
      - ISO: support SCM_TIMESTAMPING for ISO TS

   - Bluetooth drivers:
      - intel_pcie: support Function Level Reset
      - nxpuart: add support for 4M baudrate
      - nxpuart: implement powerup sequence, reset, FW dump, and FW loading"

* tag 'net-next-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1742 commits)
  dpll: zl3073x: Fix build failure
  selftests: bpf: fix legacy netfilter options
  ipv6: annotate data-races around rt->fib6_nsiblings
  ipv6: fix possible infinite loop in fib6_info_uses_dev()
  ipv6: prevent infinite loop in rt6_nlmsg_size()
  ipv6: add a retry logic in net6_rt_notify()
  vrf: Drop existing dst reference in vrf_ip6_input_dst
  net/sched: taprio: align entry index attr validation with mqprio
  net: fsl_pq_mdio: use dev_err_probe
  selftests: rtnetlink.sh: remove esp4_offload after test
  vsock: remove unnecessary null check in vsock_getname()
  igb: xsk: solve negative overflow of nb_pkts in zerocopy mode
  stmmac: xsk: fix negative overflow of budget in zerocopy mode
  dt-bindings: ieee802154: Convert at86rf230.txt yaml format
  net: dsa: microchip: Disable PTP function of KSZ8463
  net: dsa: microchip: Setup fiber ports for KSZ8463
  net: dsa: microchip: Write switch MAC address differently for KSZ8463
  net: dsa: microchip: Use different registers for KSZ8463
  net: dsa: microchip: Add KSZ8463 switch support to KSZ DSA driver
  dt-bindings: net: dsa: microchip: Add KSZ8463 switch support
  ...
2025-07-30 08:58:55 -07:00
Linus Torvalds 22c5696e3f Driver core changes for 6.17-rc1
- DEBUGFS
 
   - Remove unneeded debugfs_file_{get,put}() instances
 
   - Remove last remnants of debugfs_real_fops()
 
   - Allow storing non-const void * in struct debugfs_inode_info::aux
 
 - SYSFS
 
   - Switch back to attribute_group::bin_attrs (treewide)
 
   - Switch back to bin_attribute::read()/write() (treewide)
 
   - Constify internal references to 'struct bin_attribute'
 
 - Support cache-ids for device-tree systems
 
   - Add arch hook arch_compact_of_hwid()
 
   - Use arch_compact_of_hwid() to compact MPIDR values on arm64
 
 - Rust
 
   - Device
 
     - Introduce CoreInternal device context (for bus internal methods)
 
     - Provide generic drvdata accessors for bus devices
 
     - Provide Driver::unbind() callbacks
 
     - Use the infrastructure above for auxiliary, PCI and platform
 
     - Implement Device::as_bound()
 
     - Rename Device::as_ref() to Device::from_raw() (treewide)
 
     - Implement fwnode and device property abstractions
 
       - Implement example usage in the Rust platform sample driver
 
   - Devres
 
     - Remove the inner reference count (Arc) and use pin-init instead
 
     - Replace Devres::new_foreign_owned() with devres::register()
 
     - Require T to be Send in Devres<T>
 
     - Initialize the data kept inside a Devres last
 
     - Provide an accessor for the Devres associated Device
 
   - Device ID
 
     - Add support for ACPI device IDs and driver match tables
 
     - Split up generic device ID infrastructure
 
     - Use generic device ID infrastructure in net::phy
 
   - DMA
 
     - Implement the dma::Device trait
 
     - Add DMA mask accessors to dma::Device
 
     - Implement dma::Device for PCI and platform devices
 
     - Use DMA masks from the DMA sample module
 
   - I/O
 
     - Implement abstraction for resource regions (struct resource)
 
     - Implement resource-based ioremap() abstractions
 
     - Provide platform device accessors for I/O (remap) requests
 
   - Misc
 
     - Support fallible PinInit types in Revocable
 
     - Implement Wrapper<T> for Opaque<T>
 
     - Merge pin-init blanket dependencies (for Devres)
 
 - Misc
 
   - Fix OF node leak in auxiliary_device_create()
 
   - Use util macros in device property iterators
 
   - Improve kobject sample code
 
   - Add device_link_test() for testing device link flags
 
   - Fix typo in Documentation/ABI/testing/sysfs-kernel-address_bits
 
   - Hint to prefer container_of_const() over container_of()
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Merge tag 'driver-core-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core

Pull driver core updates from Danilo Krummrich:
 "debugfs:
   - Remove unneeded debugfs_file_{get,put}() instances
   - Remove last remnants of debugfs_real_fops()
   - Allow storing non-const void * in struct debugfs_inode_info::aux

  sysfs:
   - Switch back to attribute_group::bin_attrs (treewide)
   - Switch back to bin_attribute::read()/write() (treewide)
   - Constify internal references to 'struct bin_attribute'

  Support cache-ids for device-tree systems:
   - Add arch hook arch_compact_of_hwid()
   - Use arch_compact_of_hwid() to compact MPIDR values on arm64

  Rust:
   - Device:
       - Introduce CoreInternal device context (for bus internal methods)
       - Provide generic drvdata accessors for bus devices
       - Provide Driver::unbind() callbacks
       - Use the infrastructure above for auxiliary, PCI and platform
       - Implement Device::as_bound()
       - Rename Device::as_ref() to Device::from_raw() (treewide)
       - Implement fwnode and device property abstractions
       - Implement example usage in the Rust platform sample driver
   - Devres:
       - Remove the inner reference count (Arc) and use pin-init instead
       - Replace Devres::new_foreign_owned() with devres::register()
       - Require T to be Send in Devres<T>
       - Initialize the data kept inside a Devres last
       - Provide an accessor for the Devres associated Device
   - Device ID:
       - Add support for ACPI device IDs and driver match tables
       - Split up generic device ID infrastructure
       - Use generic device ID infrastructure in net::phy
   - DMA:
       - Implement the dma::Device trait
       - Add DMA mask accessors to dma::Device
       - Implement dma::Device for PCI and platform devices
       - Use DMA masks from the DMA sample module
   - I/O:
       - Implement abstraction for resource regions (struct resource)
       - Implement resource-based ioremap() abstractions
       - Provide platform device accessors for I/O (remap) requests
   - Misc:
       - Support fallible PinInit types in Revocable
       - Implement Wrapper<T> for Opaque<T>
       - Merge pin-init blanket dependencies (for Devres)

  Misc:
   - Fix OF node leak in auxiliary_device_create()
   - Use util macros in device property iterators
   - Improve kobject sample code
   - Add device_link_test() for testing device link flags
   - Fix typo in Documentation/ABI/testing/sysfs-kernel-address_bits
   - Hint to prefer container_of_const() over container_of()"

* tag 'driver-core-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (84 commits)
  rust: io: fix broken intra-doc links to `platform::Device`
  rust: io: fix broken intra-doc link to missing `flags` module
  rust: io: mem: enable IoRequest doc-tests
  rust: platform: add resource accessors
  rust: io: mem: add a generic iomem abstraction
  rust: io: add resource abstraction
  rust: samples: dma: set DMA mask
  rust: platform: implement the `dma::Device` trait
  rust: pci: implement the `dma::Device` trait
  rust: dma: add DMA addressing capabilities
  rust: dma: implement `dma::Device` trait
  rust: net::phy Change module_phy_driver macro to use module_device_table macro
  rust: net::phy represent DeviceId as transparent wrapper over mdio_device_id
  rust: device_id: split out index support into a separate trait
  device: rust: rename Device::as_ref() to Device::from_raw()
  arm64: cacheinfo: Provide helper to compress MPIDR value into u32
  cacheinfo: Add arch hook to compress CPU h/w id into 32 bits for cache-id
  cacheinfo: Set cache 'id' based on DT data
  container_of: Document container_of() is not to be used in new code
  driver core: auxiliary bus: fix OF node leak
  ...
2025-07-29 12:15:39 -07:00
KaFai Wan 863aab3d4d bpf: Add log for attaching tracing programs to functions in deny list
Show the rejected function name when attaching tracing programs to
functions in deny list.

With this change, we know why tracing programs can't attach to functions
like __rcu_read_lock() from log.

$ ./fentry
libbpf: prog '__rcu_read_lock': BPF program load failed: -EINVAL
libbpf: prog '__rcu_read_lock': -- BEGIN PROG LOAD LOG --
Attaching tracing programs to function '__rcu_read_lock' is rejected.

Suggested-by: Leon Hwang <leon.hwang@linux.dev>
Signed-off-by: KaFai Wan <kafai.wan@linux.dev>
Acked-by: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20250724151454.499040-3-kafai.wan@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-28 19:39:29 -07:00
KaFai Wan a5a6b29a70 bpf: Show precise rejected function when attaching fexit/fmod_ret to __noreturn functions
With this change, we know the precise rejected function name when
attaching fexit/fmod_ret to __noreturn functions from log.

$ ./fexit
libbpf: prog 'fexit': BPF program load failed: -EINVAL
libbpf: prog 'fexit': -- BEGIN PROG LOAD LOG --
Attaching fexit/fmod_ret to __noreturn function 'do_exit' is rejected.

Suggested-by: Leon Hwang <leon.hwang@linux.dev>
Signed-off-by: KaFai Wan <kafai.wan@linux.dev>
Acked-by: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20250724151454.499040-2-kafai.wan@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-28 19:39:29 -07:00
Linus Torvalds 13150742b0 Crypto library updates for 6.17
This is the main crypto library pull request for 6.17. The main focus
 this cycle is on reorganizing the SHA-1 and SHA-2 code, providing
 high-quality library APIs for SHA-1 and SHA-2 including HMAC support,
 and establishing conventions for lib/crypto/ going forward:
 
  - Migrate the SHA-1 and SHA-512 code (and also SHA-384 which shares
    most of the SHA-512 code) into lib/crypto/. This includes both the
    generic and architecture-optimized code. Greatly simplify how the
    architecture-optimized code is integrated. Add an easy-to-use
    library API for each SHA variant, including HMAC support. Finally,
    reimplement the crypto_shash support on top of the library API.
 
  - Apply the same reorganization to the SHA-256 code (and also SHA-224
    which shares most of the SHA-256 code). This is a somewhat smaller
    change, due to my earlier work on SHA-256. But this brings in all
    the same additional improvements that I made for SHA-1 and SHA-512.
 
 There are also some smaller changes:
 
  - Move the architecture-optimized ChaCha, Poly1305, and BLAKE2s code
    from arch/$(SRCARCH)/lib/crypto/ to lib/crypto/$(SRCARCH)/. For
    these algorithms it's just a move, not a full reorganization yet.
 
  - Fix the MIPS chacha-core.S to build with the clang assembler.
 
  - Fix the Poly1305 functions to work in all contexts.
 
  - Fix a performance regression in the x86_64 Poly1305 code.
 
  - Clean up the x86_64 SHA-NI optimized SHA-1 assembly code.
 
 Note that since the new organization of the SHA code is much simpler,
 the diffstat of this pull request is negative, despite the addition of
 new fully-documented library APIs for multiple SHA and HMAC-SHA
 variants. These APIs will allow further simplifications across the
 kernel as users start using them instead of the old-school crypto API.
 (I've already written a lot of such conversion patches, removing over
 1000 more lines of code. But most of those will target 6.18 or later.)
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Merge tag 'libcrypto-updates-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux

Pull crypto library updates from Eric Biggers:
 "This is the main crypto library pull request for 6.17. The main focus
  this cycle is on reorganizing the SHA-1 and SHA-2 code, providing
  high-quality library APIs for SHA-1 and SHA-2 including HMAC support,
  and establishing conventions for lib/crypto/ going forward:

   - Migrate the SHA-1 and SHA-512 code (and also SHA-384 which shares
     most of the SHA-512 code) into lib/crypto/. This includes both the
     generic and architecture-optimized code. Greatly simplify how the
     architecture-optimized code is integrated. Add an easy-to-use
     library API for each SHA variant, including HMAC support. Finally,
     reimplement the crypto_shash support on top of the library API.

   - Apply the same reorganization to the SHA-256 code (and also SHA-224
     which shares most of the SHA-256 code). This is a somewhat smaller
     change, due to my earlier work on SHA-256. But this brings in all
     the same additional improvements that I made for SHA-1 and SHA-512.

  There are also some smaller changes:

   - Move the architecture-optimized ChaCha, Poly1305, and BLAKE2s code
     from arch/$(SRCARCH)/lib/crypto/ to lib/crypto/$(SRCARCH)/. For
     these algorithms it's just a move, not a full reorganization yet.

   - Fix the MIPS chacha-core.S to build with the clang assembler.

   - Fix the Poly1305 functions to work in all contexts.

   - Fix a performance regression in the x86_64 Poly1305 code.

   - Clean up the x86_64 SHA-NI optimized SHA-1 assembly code.

  Note that since the new organization of the SHA code is much simpler,
  the diffstat of this pull request is negative, despite the addition of
  new fully-documented library APIs for multiple SHA and HMAC-SHA
  variants.

  These APIs will allow further simplifications across the kernel as
  users start using them instead of the old-school crypto API. (I've
  already written a lot of such conversion patches, removing over 1000
  more lines of code. But most of those will target 6.18 or later)"

* tag 'libcrypto-updates-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux: (67 commits)
  lib/crypto: arm64/sha512-ce: Drop compatibility macros for older binutils
  lib/crypto: x86/sha1-ni: Convert to use rounds macros
  lib/crypto: x86/sha1-ni: Minor optimizations and cleanup
  crypto: sha1 - Remove sha1_base.h
  lib/crypto: x86/sha1: Migrate optimized code into library
  lib/crypto: sparc/sha1: Migrate optimized code into library
  lib/crypto: s390/sha1: Migrate optimized code into library
  lib/crypto: powerpc/sha1: Migrate optimized code into library
  lib/crypto: mips/sha1: Migrate optimized code into library
  lib/crypto: arm64/sha1: Migrate optimized code into library
  lib/crypto: arm/sha1: Migrate optimized code into library
  crypto: sha1 - Use same state format as legacy drivers
  crypto: sha1 - Wrap library and add HMAC support
  lib/crypto: sha1: Add HMAC support
  lib/crypto: sha1: Add SHA-1 library functions
  lib/crypto: sha1: Rename sha1_init() to sha1_init_raw()
  crypto: x86/sha1 - Rename conflicting symbol
  lib/crypto: sha2: Add hmac_sha*_init_usingrawkey()
  lib/crypto: arm/poly1305: Remove unneeded empty weak function
  lib/crypto: x86/poly1305: Fix performance regression on short messages
  ...
2025-07-28 17:58:52 -07:00
Linus Torvalds 7e7bc8335b vfs-6.17-rc1.bpf
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Merge tag 'vfs-6.17-rc1.bpf' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs bpf updates from Christian Brauner:
 "These changes allow bpf to read extended attributes from cgroupfs.

  This is useful in redirecting AF_UNIX socket connections based on
  cgroup membership of the socket. One use-case is the ability to
  implement log namespaces in systemd so services and containers are
  redirected to different journals"

* tag 'vfs-6.17-rc1.bpf' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  selftests/kernfs: test xattr retrieval
  selftests/bpf: Add tests for bpf_cgroup_read_xattr
  bpf: Mark cgroup_subsys_state->cgroup RCU safe
  bpf: Introduce bpf_cgroup_read_xattr to read xattr of cgroup's node
  kernfs: remove iattr_mutex
2025-07-28 14:42:31 -07:00
Suchit Karunakaran 5b4c54ac49 bpf: Fix various typos in verifier.c comments
This patch fixes several minor typos in comments within the BPF verifier.
No changes in functionality.

Signed-off-by: Suchit Karunakaran <suchitkarunakaran@gmail.com>
Link: https://lore.kernel.org/r/20250727081754.15986-1-suchitkarunakaran@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-28 10:02:57 -07:00
Paul Chaignon 5dbb19b16a bpf: Add third round of bounds deduction
Commit d7f0087381 ("bpf: try harder to deduce register bounds from
different numeric domains") added a second call to __reg_deduce_bounds
in reg_bounds_sync because a single call wasn't enough to converge to a
fixed point in terms of register bounds.

With patch "bpf: Improve bounds when s64 crosses sign boundary" from
this series, Eduard noticed that calling __reg_deduce_bounds twice isn't
enough anymore to converge. The first selftest added in "selftests/bpf:
Test cross-sign 64bits range refinement" highlights the need for a third
call to __reg_deduce_bounds. After instruction 7, reg_bounds_sync
performs the following bounds deduction:

  reg_bounds_sync entry:          scalar(smin=-655,smax=0xeffffeee,smin32=-783,smax32=-146)
  __update_reg_bounds:            scalar(smin=-655,smax=0xeffffeee,smin32=-783,smax32=-146)
  __reg_deduce_bounds:
      __reg32_deduce_bounds:      scalar(smin=-655,smax=0xeffffeee,smin32=-783,smax32=-146,umin32=0xfffffcf1,umax32=0xffffff6e)
      __reg64_deduce_bounds:      scalar(smin=-655,smax=0xeffffeee,smin32=-783,smax32=-146,umin32=0xfffffcf1,umax32=0xffffff6e)
      __reg_deduce_mixed_bounds:  scalar(smin=-655,smax=0xeffffeee,umin=umin32=0xfffffcf1,umax=0xffffffffffffff6e,smin32=-783,smax32=-146,umax32=0xffffff6e)
  __reg_deduce_bounds:
      __reg32_deduce_bounds:      scalar(smin=-655,smax=0xeffffeee,umin=umin32=0xfffffcf1,umax=0xffffffffffffff6e,smin32=-783,smax32=-146,umax32=0xffffff6e)
      __reg64_deduce_bounds:      scalar(smin=-655,smax=smax32=-146,umin=0xfffffffffffffd71,umax=0xffffffffffffff6e,smin32=-783,umin32=0xfffffcf1,umax32=0xffffff6e)
      __reg_deduce_mixed_bounds:  scalar(smin=-655,smax=smax32=-146,umin=0xfffffffffffffd71,umax=0xffffffffffffff6e,smin32=-783,umin32=0xfffffcf1,umax32=0xffffff6e)
  __reg_bound_offset:             scalar(smin=-655,smax=smax32=-146,umin=0xfffffffffffffd71,umax=0xffffffffffffff6e,smin32=-783,umin32=0xfffffcf1,umax32=0xffffff6e,var_off=(0xfffffffffffffc00; 0x3ff))
  __update_reg_bounds:            scalar(smin=-655,smax=smax32=-146,umin=0xfffffffffffffd71,umax=0xffffffffffffff6e,smin32=-783,umin32=0xfffffcf1,umax32=0xffffff6e,var_off=(0xfffffffffffffc00; 0x3ff))

In particular, notice how:
1. In the first call to __reg_deduce_bounds, __reg32_deduce_bounds
   learns new u32 bounds.
2. __reg64_deduce_bounds is unable to improve bounds at this point.
3. __reg_deduce_mixed_bounds derives new u64 bounds from the u32 bounds.
4. In the second call to __reg_deduce_bounds, __reg64_deduce_bounds
   improves the smax and umin bounds thanks to patch "bpf: Improve
   bounds when s64 crosses sign boundary" from this series.
5. Subsequent functions are unable to improve the ranges further (only
   tnums). Yet, a better smin32 bound could be learned from the smin
   bound.

__reg32_deduce_bounds is able to improve smin32 from smin, but for that
we need a third call to __reg_deduce_bounds.

As discussed in [1], there may be a better way to organize the deduction
rules to learn the same information with less calls to the same
functions. Such an optimization requires further analysis and is
orthogonal to the present patchset.

Link: https://lore.kernel.org/bpf/aIKtSK9LjQXB8FLY@mail.gmail.com/ [1]
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Co-developed-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Link: https://lore.kernel.org/r/79619d3b42e5525e0e174ed534b75879a5ba15de.1753695655.git.paul.chaignon@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-28 10:02:13 -07:00
Paul Chaignon 00bf8d0c6c bpf: Improve bounds when s64 crosses sign boundary
__reg64_deduce_bounds currently improves the s64 range using the u64
range and vice versa, but only if it doesn't cross the sign boundary.

This patch improves __reg64_deduce_bounds to cover the case where the
s64 range crosses the sign boundary but overlaps with the u64 range on
only one end. In that case, we can improve both ranges. Consider the
following example, with the s64 range crossing the sign boundary:

    0                                                   U64_MAX
    |  [xxxxxxxxxxxxxx u64 range xxxxxxxxxxxxxx]              |
    |----------------------------|----------------------------|
    |xxxxx s64 range xxxxxxxxx]                       [xxxxxxx|
    0                     S64_MAX S64_MIN                    -1

The u64 range overlaps only with positive portion of the s64 range. We
can thus derive the following new s64 and u64 ranges.

    0                                                   U64_MAX
    |  [xxxxxx u64 range xxxxx]                               |
    |----------------------------|----------------------------|
    |  [xxxxxx s64 range xxxxx]                               |
    0                     S64_MAX S64_MIN                    -1

The same logic can probably apply to the s32/u32 ranges, but this patch
doesn't implement that change.

In addition to the selftests, the __reg64_deduce_bounds change was
also tested with Agni, the formal verification tool for the range
analysis [1].

Link: https://github.com/bpfverif/agni [1]
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Link: https://lore.kernel.org/r/933bd9ce1f36ded5559f92fdc09e5dbc823fa245.1753695655.git.paul.chaignon@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-28 10:02:12 -07:00
Paul Chaignon 5345e64760 bpf: Simplify bounds refinement from s32
During the bounds refinement, we improve the precision of various ranges
by looking at other ranges. Among others, we improve the following in
this order (other things happen between 1 and 2):

  1. Improve u32 from s32 in __reg32_deduce_bounds.
  2. Improve s/u64 from u32 in __reg_deduce_mixed_bounds.
  3. Improve s/u64 from s32 in __reg_deduce_mixed_bounds.

In particular, if the s32 range forms a valid u32 range, we will use it
to improve the u32 range in __reg32_deduce_bounds. In
__reg_deduce_mixed_bounds, under the same condition, we will use the s32
range to improve the s/u64 ranges.

If at (1) we were able to learn from s32 to improve u32, we'll then be
able to use that in (2) to improve s/u64. Hence, as (3) happens under
the same precondition as (1), it won't improve s/u64 ranges further than
(1)+(2) did. Thus, we can get rid of (3).

In addition to the extensive suite of selftests for bounds refinement,
this patch was also tested with the Agni formal verification tool [1].

Additionally, Eduard mentioned:

  The argument appears to be as follows:

  Under precondition `(u32)reg->s32_min <= (u32)reg->s32_max`
  __reg32_deduce_bounds produces:

    reg->u32_min = max_t(u32, reg->s32_min, reg->u32_min);
    reg->u32_max = min_t(u32, reg->s32_max, reg->u32_max);

  And then first part of __reg_deduce_mixed_bounds assigns:

    a. reg->umin umax= (reg->umin & ~0xffffffffULL) | max_t(u32, reg->s32_min, reg->u32_min);
    b. reg->umax umin= (reg->umax & ~0xffffffffULL) | min_t(u32, reg->s32_max, reg->u32_max);

  And then second part of __reg_deduce_mixed_bounds assigns:

    c. reg->umin umax= (reg->umin & ~0xffffffffULL) | (u32)reg->s32_min;
    d. reg->umax umin= (reg->umax & ~0xffffffffULL) | (u32)reg->s32_max;

  But assignment (c) is a noop because:

     max_t(u32, reg->s32_min, reg->u32_min) >= (u32)reg->s32_min

  Hence RHS(a) >= RHS(c) and umin= does nothing.

  Also assignment (d) is a noop because:

    min_t(u32, reg->s32_max, reg->u32_max) <= (u32)reg->s32_max

  Hence RHS(b) <= RHS(d) and umin= does nothing.

  Plus the same reasoning for the part dealing with reg->s{min,max}_value:

    e. reg->smin_value smax= (reg->smin_value & ~0xffffffffULL) | max_t(u32, reg->s32_min_value, reg->u32_min_value);
    f. reg->smax_value smin= (reg->smax_value & ~0xffffffffULL) | min_t(u32, reg->s32_max_value, reg->u32_max_value);

      vs

    g. reg->smin_value smax= (reg->smin_value & ~0xffffffffULL) | (u32)reg->s32_min_value;
    h. reg->smax_value smin= (reg->smax_value & ~0xffffffffULL) | (u32)reg->s32_max_value;

      RHS(e) >= RHS(g) and RHS(f) <= RHS(h), hence smax=,smin= do nothing.

  This appears to be correct.

Also, Shung-Hsi:

  Beside going through the reasoning, I also played with CBMC a bit to
  double check that as far as a single run of __reg_deduce_bounds() is
  concerned (and that the register state matches certain handwavy
  expectations), the change indeed still preserve the original behavior.

Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://github.com/bpfverif/agni [1]
Link: https://lore.kernel.org/bpf/aIJwnFnFyUjNsCNa@mail.gmail.com
2025-07-27 19:23:29 +02:00
Puranjay Mohan 3ba58312e6 bpf: Move bpf_jit_get_prog_name() to core.c
bpf_jit_get_prog_name() will be used by all JITs when enabling support
for private stack. This function is currently implemented in the x86
JIT.

Move the function to core.c so that other JITs can easily use it in
their implementation of private stack.

Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/bpf/20250724120257.7299-2-puranjay@kernel.org
2025-07-26 21:26:51 +02:00
Thomas Weißschuh b7b3500bd4 umd: Remove usermode driver framework
The code is unused since 98e20e5e13 ("bpfilter: remove bpfilter"),
therefore remove it.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Link: https://lore.kernel.org/bpf/20250721-remove-usermode-driver-v1-2-0d0083334382@linutronix.de
2025-07-26 21:03:04 +02:00
Thomas Weißschuh 2b03164eee bpf/preload: Don't select USERMODE_DRIVER
The usermode driver framework is not used anymore by the BPF
preload code.

Fixes: cb80ddc671 ("bpf: Convert bpf_preload.ko to use light skeleton.")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/bpf/20250721-remove-usermode-driver-v1-1-0d0083334382@linutronix.de
2025-07-26 21:02:48 +02:00
Samiullah Khawaja 71c52411c5 net: Create separate gro_flush_normal function
Move multiple copies of same code snippet doing `gro_flush` and
`gro_normal_list` into separate helper function.

Signed-off-by: Samiullah Khawaja <skhawaja@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250723013031.2911384-2-skhawaja@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-24 18:34:55 -07:00
Jakub Kicinski a4f5759b6f bpf-next-for-netdev
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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Martin KaFai Lau says:

====================
pull-request: bpf-next 2025-07-24

We've added 3 non-merge commits during the last 3 day(s) which contain
a total of 4 files changed, 40 insertions(+), 15 deletions(-).

The main changes are:

1) Improved verifier error message for incorrect narrower load from
   pointer field in ctx, from Paul Chaignon.

2) Disabled migration in nf_hook_run_bpf to address a syzbot report,
   from Kuniyuki Iwashima.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next:
  selftests/bpf: Test invalid narrower ctx load
  bpf: Reject narrower access to pointer ctx fields
  bpf: Disable migration in nf_hook_run_bpf().
====================

Link: https://patch.msgid.link/20250724173306.3578483-1-martin.lau@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-24 18:02:24 -07:00
Paul Chaignon e09299225d bpf: Reject narrower access to pointer ctx fields
The following BPF program, simplified from a syzkaller repro, causes a
kernel warning:

    r0 = *(u8 *)(r1 + 169);
    exit;

With pointer field sk being at offset 168 in __sk_buff. This access is
detected as a narrower read in bpf_skb_is_valid_access because it
doesn't match offsetof(struct __sk_buff, sk). It is therefore allowed
and later proceeds to bpf_convert_ctx_access. Note that for the
"is_narrower_load" case in the convert_ctx_accesses(), the insn->off
is aligned, so the cnt may not be 0 because it matches the
offsetof(struct __sk_buff, sk) in the bpf_convert_ctx_access. However,
the target_size stays 0 and the verifier errors with a kernel warning:

    verifier bug: error during ctx access conversion(1)

This patch fixes that to return a proper "invalid bpf_context access
off=X size=Y" error on the load instruction.

The same issue affects multiple other fields in context structures that
allow narrow access. Some other non-affected fields (for sk_msg,
sk_lookup, and sockopt) were also changed to use bpf_ctx_range_ptr for
consistency.

Note this syzkaller crash was reported in the "Closes" link below, which
used to be about a different bug, fixed in
commit fce7bd8e38 ("bpf/verifier: Handle BPF_LOAD_ACQ instructions
in insn_def_regno()"). Because syzbot somehow confused the two bugs,
the new crash and repro didn't get reported to the mailing list.

Fixes: f96da09473 ("bpf: simplify narrower ctx access")
Fixes: 0df1a55afa ("bpf: Warn on internal verifier errors")
Reported-by: syzbot+0ef84a7bdf5301d4cbec@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=0ef84a7bdf5301d4cbec
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://patch.msgid.link/3b8dcee67ff4296903351a974ddd9c4dca768b64.1753194596.git.paul.chaignon@gmail.com
2025-07-23 19:33:49 -07:00
Yonghong Song 95993dc303 bpf: Use ERR_CAST instead of ERR_PTR(PTR_ERR(...))
Intel linux test robot reported a warning that ERR_CAST can be used
for error pointer casting instead of more-complicated/rarely-used
ERR_PTR(PTR_ERR(...)) style.

There is no functionality change, but still let us replace two such
instances as it improves consistency and readability.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202507201048.bceHy8zX-lkp@intel.com/
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://patch.msgid.link/20250720164754.3999140-1-yonghong.song@linux.dev
2025-07-21 17:27:09 -07:00
Alexei Starovoitov beb1097ec8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf after rc6
Cross-merge BPF and other fixes after downstream PR.

No conflicts.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-18 12:15:59 -07:00
Lorenz Bauer 2e2713ae1a btf: Fix virt_to_phys() on arm64 when mmapping BTF
Breno Leitao reports that arm64 emits the following warning
with CONFIG_DEBUG_VIRTUAL:

    [   58.896157] virt_to_phys used for non-linear address: 000000009fea9737
      (__start_BTF+0x0/0x685530)
    [   23.988669] WARNING: CPU: 25 PID: 1442 at arch/arm64/mm/physaddr.c:15
      __virt_to_phys (arch/arm64/mm/physaddr.c:?)

        ...

    [   24.075371] Tainted: [E]=UNSIGNED_MODULE, [N]=TEST
    [   24.080276] Hardware name: Quanta S7GM 20S7GCU0010/S7G MB (CG1), BIOS 3D22
      07/03/2024
    [   24.088295] pstate: 63400009 (nZCv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
    [   24.098440] pc : __virt_to_phys (arch/arm64/mm/physaddr.c:?)
    [   24.105398] lr : __virt_to_phys (arch/arm64/mm/physaddr.c:?)

	...

    [   24.197257] Call trace:
    [   24.199761] __virt_to_phys (arch/arm64/mm/physaddr.c:?) (P)
    [   24.206883] btf_sysfs_vmlinux_mmap (kernel/bpf/sysfs_btf.c:27)
    [   24.214264] sysfs_kf_bin_mmap (fs/sysfs/file.c:179)
    [   24.218536] kernfs_fop_mmap (fs/kernfs/file.c:462)
    [   24.222461] mmap_region (./include/linux/fs.h:? mm/internal.h:167
       mm/vma.c:2405 mm/vma.c:2467 mm/vma.c:2622 mm/vma.c:2692)

It seems that the memory layout on arm64 maps the kernel image in vmalloc space
which is different than x86. This makes virt_to_phys emit the warning.

Fix this by translating the address using __pa_symbol as suggested by
Breno instead.

Reported-by: Breno Leitao <leitao@debian.org>
Closes: https://lore.kernel.org/bpf/g2gqhkunbu43awrofzqb4cs4sxkxg2i4eud6p4qziwrdh67q4g@mtw3d3aqfgmb/
Signed-off-by: Lorenz Bauer <lmb@isovalent.com>
Tested-by: Breno Leitao <leitao@debian>
Fixes: a539e2a6d5 ("btf: Allow mmap of vmlinux btf")
Link: https://lore.kernel.org/r/20250717-vmlinux-mmap-pa-symbol-v1-1-970be6681158@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-17 11:33:52 -07:00
Tao Chen 19d18fdfc7 bpf: Add struct bpf_token_info
The 'commit 35f96de041 ("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>
2025-07-16 18:38:05 -07:00
Feng Yang 62ef449b8d bpf: Clean up individual BTF_ID code
Use BTF_ID_LIST_SINGLE(a, b, c) instead of
BTF_ID_LIST(a)
BTF_ID(b, c)

Signed-off-by: Feng Yang <yangfeng@kylinos.cn>
Link: https://lore.kernel.org/r/20250710055419.70544-1-yangfeng59949@163.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-16 18:34:42 -07:00
Ilya Leoshkevich 1f489662fb bpf: Update iterators.lskel-big-endian.h
The last iterators update (commit 515ee52b22 ("bpf: make preloaded
map iterators to display map elements count")) missed the big-endian
skeleton. Update it by running "make big" with Debian clang version
21.0.0 (++20250706105601+01c97b4953e8-1~exp1~20250706225612.1558).

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/r/20250710100907.45880-1-iii@linux.ibm.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-16 18:29:18 -07:00
Eric Biggers 9503ca2cca lib/crypto: sha1: Rename sha1_init() to sha1_init_raw()
Rename the existing sha1_init() to sha1_init_raw(), since it conflicts
with the upcoming library function.  This will later be removed, but
this keeps the kernel building for the introduction of the library.

Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20250712232329.818226-3-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
2025-07-14 08:22:31 -07:00
Tao Chen 0eeeebdcc5 bpf: Remove attach_type in bpf_tracing_link
Use attach_type in bpf_link, and remove it in bpf_tracing_link.

Signed-off-by: Tao Chen <chen.dylane@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20250710032038.888700-7-chen.dylane@linux.dev
2025-07-11 11:01:08 -07:00
Tao Chen 2a76a80c7f bpf: Remove attach_type in bpf_netns_link
Use attach_type in bpf_link, and remove it in bpf_netns_link.
And move netns_type field to the end to fill the byte hole.

Signed-off-by: Tao Chen <chen.dylane@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20250710032038.888700-6-chen.dylane@linux.dev
2025-07-11 11:01:04 -07:00
Tao Chen 6e816e1c05 bpf: Remove location field in tcx_link
Use attach_type in bpf_link to replace the location filed, and
remove location field in tcx_link.

Signed-off-by: Tao Chen <chen.dylane@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20250710032038.888700-5-chen.dylane@linux.dev
2025-07-11 11:00:57 -07:00
Tao Chen 9b8d543dc2 bpf: Remove attach_type in bpf_cgroup_link
Use attach_type in bpf_link, and remove it in bpf_cgroup_link.

Signed-off-by: Tao Chen <chen.dylane@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20250710032038.888700-3-chen.dylane@linux.dev
2025-07-11 10:51:55 -07:00
Tao Chen b725441f02 bpf: Add attach_type field to bpf_link
Attach_type will be set when a link is created by user. It is better to
record attach_type in bpf_link generically and have it available
universally for all link types. So add the attach_type field in bpf_link
and move the sleepable field to avoid unnecessary gap padding.

Signed-off-by: Tao Chen <chen.dylane@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20250710032038.888700-2-chen.dylane@linux.dev
2025-07-11 10:51:55 -07:00
Paul Chaignon 6279846b9b bpf: Forget ranges when refining tnum after JSET
Syzbot reported a kernel warning due to a range invariant violation on
the following BPF program.

  0: call bpf_get_netns_cookie
  1: if r0 == 0 goto <exit>
  2: if r0 & Oxffffffff goto <exit>

The issue is on the path where we fall through both jumps.

That path is unreachable at runtime: after insn 1, we know r0 != 0, but
with the sign extension on the jset, we would only fallthrough insn 2
if r0 == 0. Unfortunately, is_branch_taken() isn't currently able to
figure this out, so the verifier walks all branches. The verifier then
refines the register bounds using the second condition and we end
up with inconsistent bounds on this unreachable path:

  1: if r0 == 0 goto <exit>
    r0: u64=[0x1, 0xffffffffffffffff] var_off=(0, 0xffffffffffffffff)
  2: if r0 & 0xffffffff goto <exit>
    r0 before reg_bounds_sync: u64=[0x1, 0xffffffffffffffff] var_off=(0, 0)
    r0 after reg_bounds_sync:  u64=[0x1, 0] var_off=(0, 0)

Improving the range refinement for JSET to cover all cases is tricky. We
also don't expect many users to rely on JSET given LLVM doesn't generate
those instructions. So instead of improving the range refinement for
JSETs, Eduard suggested we forget the ranges whenever we're narrowing
tnums after a JSET. This patch implements that approach.

Reported-by: syzbot+c711ce17dd78e5d4fdcf@syzkaller.appspotmail.com
Suggested-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Link: https://lore.kernel.org/r/9d4fd6432a095d281f815770608fdcd16028ce0b.1752171365.git.paul.chaignon@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-11 10:45:25 -07:00
Emil Tsalapatis 8fc3d2d8b5 bpf/arena: add bpf_arena_reserve_pages kfunc
Add a new BPF arena kfunc for reserving a range of arena virtual
addresses without backing them with pages. This prevents the range from
being populated using bpf_arena_alloc_pages().

Acked-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Emil Tsalapatis <emil@etsalapatis.com>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20250709191312.29840-2-emil@etsalapatis.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-11 10:43:54 -07:00
Tao Chen 3413bc0cf1 bpf: Clean code with bpf_copy_to_user()
No logic change, use bpf_copy_to_user() to clean code.

Signed-off-by: Tao Chen <chen.dylane@linux.dev>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20250703163700.677628-1-chen.dylane@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-07 08:53:59 -07:00
Luis Gerhorst dadb59104c bpf: Fix aux usage after do_check_insn()
We must terminate the speculative analysis if the just-analyzed insn had
nospec_result set. Using cur_aux() here is wrong because insn_idx might
have been incremented by do_check_insn(). Therefore, introduce and use
insn_aux variable.

Also change cur_aux(env)->nospec in case do_check_insn() ever manages to
increment insn_idx but still fail.

Change the warning to check the insn class (which prevents it from
triggering for ldimm64, for which nospec_result would not be
problematic) and use verifier_bug_if().

In line with Eduard's suggestion, do not introduce prev_aux() because
that requires one to understand that after do_check_insn() call what was
current became previous. This would at-least require a comment.

Fixes: d6f1c85f22 ("bpf: Fall back to nospec for Spectre v1")
Reported-by: Paul Chaignon <paul.chaignon@gmail.com>
Reported-by: Eduard Zingerman <eddyz87@gmail.com>
Reported-by: syzbot+dc27c5fb8388e38d2d37@syzkaller.appspotmail.com
Link: https://lore.kernel.org/bpf/685b3c1b.050a0220.2303ee.0010.GAE@google.com/
Link: https://lore.kernel.org/bpf/4266fd5de04092aa4971cbef14f1b4b96961f432.camel@gmail.com/
Suggested-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Luis Gerhorst <luis.gerhorst@fau.de>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250705190908.1756862-2-luis.gerhorst@fau.de
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-07 08:32:34 -07:00
Kumar Kartikeya Dwivedi bfa2bb9abd bpf: Fix improper int-to-ptr cast in dump_stack_cb
On 32-bit platforms, we'll try to convert a u64 directly to a pointer
type which is 32-bit, which causes the compiler to complain about cast
from an integer of a different size to a pointer type. Cast to long
before casting to the pointer type to match the pointer width.

Reported-by: kernelci.org bot <bot@kernelci.org>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Fixes: d7c431cafc ("bpf: Add dump_stack() analogue to print to BPF stderr")
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20250705053035.3020320-3-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-07 08:30:15 -07:00
Kumar Kartikeya Dwivedi 116c8f4747 bpf: Fix bounds for bpf_prog_get_file_line linfo loop
We may overrun the bounds because linfo and jited_linfo are already
advanced to prog->aux->linfo_idx, hence we must only iterate the
remaining elements until we reach prog->aux->nr_linfo. Adjust the
nr_linfo calculation to fix this. Reported in [0].

  [0]: https://lore.kernel.org/bpf/f3527af3b0620ce36e299e97e7532d2555018de2.camel@gmail.com

Reported-by: Eduard Zingerman <eddyz87@gmail.com>
Fixes: 0e521efaf3 ("bpf: Add function to extract program source info")
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250705053035.3020320-2-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-07 08:30:15 -07:00
Eduard Zingerman c4aa454c64 bpf: support for void/primitive __arg_untrusted global func params
Allow specifying __arg_untrusted for void */char */int */long *
parameters. Treat such parameters as
PTR_TO_MEM|MEM_RDONLY|PTR_UNTRUSTED of size zero.
Intended usage is as follows:

  int memcmp(char *a __arg_untrusted, char *b __arg_untrusted, size_t n) {
    bpf_for(i, 0, n) {
      if (a[i] - b[i])      // load at any offset is allowed
        return a[i] - b[i];
    }
    return 0;
  }

Allocate register id for ARG_PTR_TO_MEM parameters only when
PTR_MAYBE_NULL is set. Register id for PTR_TO_MEM is used only to
propagate non-null status after conditionals.

Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250704230354.1323244-8-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-07 08:25:07 -07:00
Eduard Zingerman 182f7df704 bpf: attribute __arg_untrusted for global function parameters
Add support for PTR_TO_BTF_ID | PTR_UNTRUSTED global function
parameters. Anything is allowed to pass to such parameters, as these
are read-only and probe read instructions would protect against
invalid memory access.

Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250704230354.1323244-5-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-07 08:25:06 -07:00
Eduard Zingerman 2d5c91e1cc bpf: rdonly_untrusted_mem for btf id walk pointer leafs
When processing a load from a PTR_TO_BTF_ID, the verifier calculates
the type of the loaded structure field based on the load offset.
For example, given the following types:

  struct foo {
    struct foo *a;
    int *b;
  } *p;

The verifier would calculate the type of `p->a` as a pointer to
`struct foo`. However, the type of `p->b` is currently calculated as a
SCALAR_VALUE.

This commit updates the logic for processing PTR_TO_BTF_ID to instead
calculate the type of p->b as PTR_TO_MEM|MEM_RDONLY|PTR_UNTRUSTED.
This change allows further dereferencing of such pointers (using probe
memory instructions).

Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250704230354.1323244-3-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-07 08:25:06 -07:00
Eduard Zingerman b9d44bc9fd bpf: make makr_btf_ld_reg return error for unexpected reg types
Non-functional change:
mark_btf_ld_reg() expects 'reg_type' parameter to be either
SCALAR_VALUE or PTR_TO_BTF_ID. Next commit expands this set, so update
this function to fail if unexpected type is passed. Also update
callers to propagate the error.

Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250704230354.1323244-2-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-07 08:25:06 -07:00
Yonghong Song 82bc4abf28 bpf: Avoid putting struct bpf_scc_callchain variables on the stack
Add a 'struct bpf_scc_callchain callchain_buf' field in bpf_verifier_env.
This way, the previous bpf_scc_callchain local variables can be
replaced by taking address of env->callchain_buf. This can reduce stack
usage and fix the following error:
    kernel/bpf/verifier.c:19921:12: error: stack frame size (1368) exceeds limit (1280) in 'do_check'
        [-Werror,-Wframe-larger-than]

Reported-by: Arnd Bergmann <arnd@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20250703141117.1485108-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-03 19:31:30 -07:00
Yonghong Song 45e9cd38aa bpf: Reduce stack frame size by using env->insn_buf for bpf insns
Arnd Bergmann reported an issue ([1]) where clang compiler (less than
llvm18) may trigger an error where the stack frame size exceeds the limit.
I can reproduce the error like below:
  kernel/bpf/verifier.c:24491:5: error: stack frame size (2552) exceeds limit (1280) in 'bpf_check'
      [-Werror,-Wframe-larger-than]
  kernel/bpf/verifier.c:19921:12: error: stack frame size (1368) exceeds limit (1280) in 'do_check'
      [-Werror,-Wframe-larger-than]

Use env->insn_buf for bpf insns instead of putting these insns on the
stack. This can resolve the above 'bpf_check' error. The 'do_check' error
will be resolved in the next patch.

  [1] https://lore.kernel.org/bpf/20250620113846.3950478-1-arnd@kernel.org/

Reported-by: Arnd Bergmann <arnd@kernel.org>
Tested-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20250703141111.1484521-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-03 19:31:29 -07:00
Yonghong Song 3b87251439 bpf: Simplify assignment to struct bpf_insn pointer in do_misc_fixups()
In verifier.c, the following code patterns (in two places)
  struct bpf_insn *patch = &insn_buf[0];
can be simplified to
  struct bpf_insn *patch = insn_buf;
which is easier to understand.

Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20250703141106.1483216-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-03 19:31:29 -07:00
Paul Chaignon 032547272e bpf: Avoid warning on unexpected map for tail call
Before handling the tail call in record_func_key(), we check that the
map is of the expected type and log a verifier error if it isn't. Such
an error however doesn't indicate anything wrong with the verifier. The
check for map<>func compatibility is done after record_func_key(), by
check_map_func_compatibility().

Therefore, this patch logs the error as a typical reject instead of a
verifier error.

Fixes: d2e4c1e6c2 ("bpf: Constant map key tracking for prog array pokes")
Fixes: 0df1a55afa ("bpf: Warn on internal verifier errors")
Reported-by: syzbot+efb099d5833bca355e51@syzkaller.appspotmail.com
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/1f395b74e73022e47e04a31735f258babf305420.1751578055.git.paul.chaignon@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-03 19:30:54 -07:00
Kumar Kartikeya Dwivedi ecec5b5743 bpf: Report rqspinlock deadlocks/timeout to BPF stderr
Begin reporting rqspinlock deadlocks and timeout to BPF program's
stderr.

Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20250703204818.925464-9-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-03 19:30:07 -07:00
Kumar Kartikeya Dwivedi e8d0133022 bpf: Report may_goto timeout to BPF stderr
Begin reporting may_goto timeouts to BPF program's stderr stream.

Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20250703204818.925464-8-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-03 19:30:07 -07:00
Kumar Kartikeya Dwivedi d7c431cafc bpf: Add dump_stack() analogue to print to BPF stderr
Introduce a kernel function which is the analogue of dump_stack()
printing some useful information and the stack trace. This is not
exposed to BPF programs yet, but can be made available in the future.

When we have a program counter for a BPF program in the stack trace,
also additionally output the filename and line number to make the trace
helpful. The rest of the trace can be passed into ./decode_stacktrace.sh
to obtain the line numbers for kernel symbols.

Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20250703204818.925464-7-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-03 19:30:07 -07:00
Kumar Kartikeya Dwivedi f0c53fd4a7 bpf: Add function to find program from stack trace
In preparation of figuring out the closest program that led to the
current point in the kernel, implement a function that scans through the
stack trace and finds out the closest BPF program when walking down the
stack trace.

Special care needs to be taken to skip over kernel and BPF subprog
frames. We basically scan until we find a BPF main prog frame. The
assumption is that if a program calls into us transitively, we'll
hit it along the way. If not, we end up returning NULL.

Contextually the function will be used in places where we know the
program may have called into us.

Due to reliance on arch_bpf_stack_walk(), this function only works on
x86 with CONFIG_UNWINDER_ORC, arm64, and s390. Remove the warning from
arch_bpf_stack_walk as well since we call it outside bpf_throw()
context.

Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20250703204818.925464-6-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-03 19:30:06 -07:00
Kumar Kartikeya Dwivedi d090326860 bpf: Ensure RCU lock is held around bpf_prog_ksym_find
Add a warning to ensure RCU lock is held around tree lookup, and then
fix one of the invocations in bpf_stack_walker. The program has an
active stack frame and won't disappear. Use the opportunity to remove
unneeded invocation of is_bpf_text_address.

Fixes: f18b03faba ("bpf: Implement BPF exceptions")
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20250703204818.925464-5-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-03 19:30:06 -07:00
Kumar Kartikeya Dwivedi 0e521efaf3 bpf: Add function to extract program source info
Prepare a function for use in future patches that can extract the file
info, line info, and the source line number for a given BPF program
provided it's program counter.

Only the basename of the file path is provided, given it can be
excessively long in some cases.

This will be used in later patches to print source info to the BPF
stream.

Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20250703204818.925464-4-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-03 19:30:06 -07:00
Kumar Kartikeya Dwivedi 5ab154f146 bpf: Introduce BPF standard streams
Add support for a stream API to the kernel and expose related kfuncs to
BPF programs. Two streams are exposed, BPF_STDOUT and BPF_STDERR. These
can be used for printing messages that can be consumed from user space,
thus it's similar in spirit to existing trace_pipe interface.

The kernel will use the BPF_STDERR stream to notify the program of any
errors encountered at runtime. BPF programs themselves may use both
streams for writing debug messages. BPF library-like code may use
BPF_STDERR to print warnings or errors on misuse at runtime.

The implementation of a stream is as follows. Everytime a message is
emitted from the kernel (directly, or through a BPF program), a record
is allocated by bump allocating from per-cpu region backed by a page
obtained using alloc_pages_nolock(). This ensures that we can allocate
memory from any context. The eventual plan is to discard this scheme in
favor of Alexei's kmalloc_nolock() [0].

This record is then locklessly inserted into a list (llist_add()) so
that the printing side doesn't require holding any locks, and works in
any context. Each stream has a maximum capacity of 4MB of text, and each
printed message is accounted against this limit.

Messages from a program are emitted using the bpf_stream_vprintk kfunc,
which takes a stream_id argument in addition to working otherwise
similar to bpf_trace_vprintk.

The bprintf buffer helpers are extracted out to be reused for printing
the string into them before copying it into the stream, so that we can
(with the defined max limit) format a string and know its true length
before performing allocations of the stream element.

For consuming elements from a stream, we expose a bpf(2) syscall command
named BPF_PROG_STREAM_READ_BY_FD, which allows reading data from the
stream of a given prog_fd into a user space buffer. The main logic is
implemented in bpf_stream_read(). The log messages are queued in
bpf_stream::log by the bpf_stream_vprintk kfunc, and then pulled and
ordered correctly in the stream backlog.

For this purpose, we hold a lock around bpf_stream_backlog_peek(), as
llist_del_first() (if we maintained a second lockless list for the
backlog) wouldn't be safe from multiple threads anyway. Then, if we
fail to find something in the backlog log, we splice out everything from
the lockless log, and place it in the backlog log, and then return the
head of the backlog. Once the full length of the element is consumed, we
will pop it and free it.

The lockless list bpf_stream::log is a LIFO stack. Elements obtained
using a llist_del_all() operation are in LIFO order, thus would break
the chronological ordering if printed directly. Hence, this batch of
messages is first reversed. Then, it is stashed into a separate list in
the stream, i.e. the backlog_log. The head of this list is the actual
message that should always be returned to the caller. All of this is
done in bpf_stream_backlog_fill().

From the kernel side, the writing into the stream will be a bit more
involved than the typical printk. First, the kernel typically may print
a collection of messages into the stream, and parallel writers into the
stream may suffer from interleaving of messages. To ensure each group of
messages is visible atomically, we can lift the advantage of using a
lockless list for pushing in messages.

To enable this, we add a bpf_stream_stage() macro, and require kernel
users to use bpf_stream_printk statements for the passed expression to
write into the stream. Underneath the macro, we have a message staging
API, where a bpf_stream_stage object on the stack accumulates the
messages being printed into a local llist_head, and then a commit
operation splices the whole batch into the stream's lockless log list.

This is especially pertinent for rqspinlock deadlock messages printed to
program streams. After this change, we see each deadlock invocation as a
non-interleaving contiguous message without any confusion on the
reader's part, improving their user experience in debugging the fault.

While programs cannot benefit from this staged stream writing API, they
could just as well hold an rqspinlock around their print statements to
serialize messages, hence this is kept kernel-internal for now.

Overall, this infrastructure provides NMI-safe any context printing of
messages to two dedicated streams.

Later patches will add support for printing splats in case of BPF arena
page faults, rqspinlock deadlocks, and cond_break timeouts, and
integration of this facility into bpftool for dumping messages to user
space.

  [0]: https://lore.kernel.org/bpf/20250501032718.65476-1-alexei.starovoitov@gmail.com

Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20250703204818.925464-3-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-03 19:30:06 -07:00
Kumar Kartikeya Dwivedi 0426729f46 bpf: Refactor bprintf buffer support
Refactor code to be able to get and put bprintf buffers and use
bpf_printf_prepare independently. This will be used in the next patch to
implement BPF streams support, particularly as a staging buffer for
strings that need to be formatted and then allocated and pushed into a
stream.

Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20250703204818.925464-2-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-03 19:30:06 -07:00
Tao Chen 803f0700a3 bpf: Show precise link_type for {uprobe,kprobe}_multi fdinfo
Alexei suggested, 'link_type' can be more precise and differentiate
for human in fdinfo. In fact BPF_LINK_TYPE_KPROBE_MULTI includes
kretprobe_multi type, the same as BPF_LINK_TYPE_UPROBE_MULTI, so we
can show it more concretely.

link_type:	kprobe_multi
link_id:	1
prog_tag:	d2b307e915f0dd37
...
link_type:	kretprobe_multi
link_id:	2
prog_tag:	ab9ea0545870781d
...
link_type:	uprobe_multi
link_id:	9
prog_tag:	e729f789e34a8eca
...
link_type:	uretprobe_multi
link_id:	10
prog_tag:	7db356c03e61a4d4

Co-developed-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Tao Chen <chen.dylane@linux.dev>
Link: https://lore.kernel.org/r/20250702153958.639852-1-chen.dylane@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-03 19:29:42 -07:00
Ihor Solodrai 5fc5d8fded bpf: Add bpf_dynptr_memset() kfunc
Currently there is no straightforward way to fill dynptr memory with a
value (most commonly zero). One can do it with bpf_dynptr_write(), but
a temporary buffer is necessary for that.

Implement bpf_dynptr_memset() - an analogue of memset() from libc.

Signed-off-by: Ihor Solodrai <isolodrai@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250702210309.3115903-2-isolodrai@meta.com
2025-07-03 15:21:20 -07:00
Paul Chaignon 65fdafd676 bpf: Avoid warning on multiple referenced args in call
The description of full helper calls in syzkaller [1] and the addition of
kernel warnings in commit 0df1a55afa ("bpf: Warn on internal verifier
errors") allowed syzbot to reach a verifier state that was thought to
indicate a verifier bug [2]:

    12: (85) call bpf_tcp_raw_gen_syncookie_ipv4#204
    verifier bug: more than one arg with ref_obj_id R2 2 2

This error can be reproduced with the program from the previous commit:

    0: (b7) r2 = 20
    1: (b7) r3 = 0
    2: (18) r1 = 0xffff92cee3cbc600
    4: (85) call bpf_ringbuf_reserve#131
    5: (55) if r0 == 0x0 goto pc+3
    6: (bf) r1 = r0
    7: (bf) r2 = r0
    8: (85) call bpf_tcp_raw_gen_syncookie_ipv4#204
    9: (95) exit

bpf_tcp_raw_gen_syncookie_ipv4 expects R1 and R2 to be
ARG_PTR_TO_FIXED_SIZE_MEM (with a size of at least sizeof(struct iphdr)
for R1). R0 is a ring buffer payload of 20B and therefore matches this
requirement.

The verifier reaches the check on ref_obj_id while verifying R2 and
rejects the program because the helper isn't supposed to take two
referenced arguments.

This case is a legitimate rejection and doesn't indicate a kernel bug,
so we shouldn't log it as such and shouldn't emit a kernel warning.

Link: https://github.com/google/syzkaller/pull/4313 [1]
Link: https://lore.kernel.org/all/686491d6.a70a0220.3b7e22.20ea.GAE@google.com/T/ [2]
Fixes: 457f44363a ("bpf: Implement BPF ring buffer and verifier support for it")
Fixes: 0df1a55afa ("bpf: Warn on internal verifier errors")
Reported-by: syzbot+69014a227f8edad4d8c6@syzkaller.appspotmail.com
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Link: https://lore.kernel.org/r/cd09afbfd7bef10bbc432d72693f78ffdc1e8ee5.1751463262.git.paul.chaignon@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
2025-07-02 10:43:38 -07:00
Eduard Zingerman c3b9faac9b bpf: avoid jump misprediction for PTR_TO_MEM | PTR_UNTRUSTED
Commit f2362a57ae ("bpf: allow void* cast using bpf_rdonly_cast()")
added a notion of PTR_TO_MEM | MEM_RDONLY | PTR_UNTRUSTED type.
This simultaneously introduced a bug in jump prediction logic for
situations like below:

  p = bpf_rdonly_cast(..., 0);
  if (p) a(); else b();

Here verifier would wrongly predict that else branch cannot be taken.
This happens because:
- Function reg_not_null() assumes that PTR_TO_MEM w/o PTR_MAYBE_NULL
  flag cannot be zero.
- The call to bpf_rdonly_cast() returns a rdonly_untrusted_mem value
  w/o PTR_MAYBE_NULL flag.

Tracking of PTR_MAYBE_NULL flag for untrusted PTR_TO_MEM does not make
sense, as the main purpose of the flag is to catch null pointer access
errors. Such errors are not possible on load of PTR_UNTRUSTED values
and verifier makes sure that PTR_UNTRUSTED can't be passed to helpers
or kfuncs.

Hence, modify reg_not_null() to assume that nullness of untrusted
PTR_TO_MEM is not known.

Fixes: f2362a57ae ("bpf: allow void* cast using bpf_rdonly_cast()")
Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250702073620.897517-1-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
2025-07-02 10:43:10 -07:00
Song Liu 5bc9557c9f
bpf: Mark cgroup_subsys_state->cgroup RCU safe
Mark struct cgroup_subsys_state->cgroup as safe under RCU read lock. This
will enable accessing css->cgroup from a bpf css iterator.

Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/20250623063854.1896364-4-song@kernel.org
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-02 14:18:20 +02:00
Song Liu b95ee9049c
bpf: Introduce bpf_cgroup_read_xattr to read xattr of cgroup's node
BPF programs, such as LSM and sched_ext, would benefit from tags on
cgroups. One common practice to apply such tags is to set xattrs on
cgroupfs folders.

Introduce kfunc bpf_cgroup_read_xattr, which allows reading cgroup's
xattr.

Note that, we already have bpf_get_[file|dentry]_xattr. However, these
two APIs are not ideal for reading cgroupfs xattrs, because:

  1) These two APIs only works in sleepable contexts;
  2) There is no kfunc that matches current cgroup to cgroupfs dentry.

bpf_cgroup_read_xattr is generic and can be useful for many program
types. It is also safe, because it requires trusted or rcu protected
argument (KF_RCU). Therefore, we make it available to all program types.

Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/20250623063854.1896364-3-song@kernel.org
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-02 14:18:20 +02:00
Paul Chaignon f824274587 bpf: Reject %p% format string in bprintf-like helpers
static const char fmt[] = "%p%";
    bpf_trace_printk(fmt, sizeof(fmt));

The above BPF program isn't rejected and causes a kernel warning at
runtime:

    Please remove unsupported %\x00 in format string
    WARNING: CPU: 1 PID: 7244 at lib/vsprintf.c:2680 format_decode+0x49c/0x5d0

This happens because bpf_bprintf_prepare skips over the second %,
detected as punctuation, while processing %p. This patch fixes it by
not skipping over punctuation. %\x00 is then processed in the next
iteration and rejected.

Reported-by: syzbot+e2c932aec5c8a6e1d31c@syzkaller.appspotmail.com
Fixes: 48cac3f4a9 ("bpf: Implement formatted output helpers with bstr_printf")
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Link: https://lore.kernel.org/r/a0e06cc479faec9e802ae51ba5d66420523251ee.1751395489.git.paul.chaignon@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-01 15:22:46 -07:00
Paul Chaignon 0df1a55afa bpf: Warn on internal verifier errors
This patch is a follow up to commit 1cb0f56d96 ("bpf: WARN_ONCE on
verifier bugs"). It generalizes the use of verifier_error throughout
the verifier, in particular for logs previously marked "verifier
internal error". As a consequence, all of those verifier bugs will now
come with a kernel warning (under CONFIG_DBEUG_KERNEL) detectable by
fuzzers.

While at it, some error messages that were too generic (ex., "bpf
verifier is misconfigured") have been reworded.

Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Link: https://lore.kernel.org/r/aGQqnzMyeagzgkCK@Tunnel
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-01 12:38:30 -07:00
Eduard Zingerman a5a7b25d75 bpf: guard BTF_ID_FLAGS(bpf_cgroup_read_xattr) with CONFIG_BPF_LSM
Function bpf_cgroup_read_xattr is defined in fs/bpf_fs_kfuncs.c,
which is compiled only when CONFIG_BPF_LSM is set. Add CONFIG_BPF_LSM
check to bpf_cgroup_read_xattr spec in common_btf_ids in
kernel/bpf/helpers.c to avoid build failures for configs w/o
CONFIG_BPF_LSM.

Build failure example:

    BTF     .tmp_vmlinux1.btf.o
  btf_encoder__tag_kfunc: failed to find kfunc 'bpf_cgroup_read_xattr' in BTF
  ...
  WARN: resolve_btfids: unresolved symbol bpf_cgroup_read_xattr
  make[2]: *** [scripts/Makefile.vmlinux:91: vmlinux.unstripped] Error 255

Fixes: 535b070f4a ("bpf: Introduce bpf_cgroup_read_xattr to read xattr of cgroup's node")
Reported-by: Jake Hillion <jakehillion@meta.com>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250627175309.2710973-1-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-06-27 12:18:42 -07:00
Viktor Malik 5272b51367 bpf: Fix string kfuncs names in doc comments
Documentation comments for bpf_strnlen and bpf_strcspn contained
incorrect function names.

Fixes: e91370550f ("bpf: Add kfuncs for read-only string operations")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Closes: https://lore.kernel.org/bpf/20250627174759.3a435f86@canb.auug.org.au/T/#u
Signed-off-by: Viktor Malik <vmalik@redhat.com>
Link: https://lore.kernel.org/r/20250627082001.237606-1-vmalik@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-06-27 08:48:06 -07:00
Alexei Starovoitov 48d998af99 Merge branch 'vfs-6.17.bpf' of https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Merge branch 'vfs-6.17.bpf' from vfs tree into bpf-next/master
and resolve conflicts.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-06-26 19:01:04 -07:00
Alexei Starovoitov 886178a33a Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf after rc3
Cross-merge BPF, perf and other fixes after downstream PRs.
It restores BPF CI to green after critical fix
commit bc4394e5e7 ("perf: Fix the throttle error of some clock events")

No conflicts.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-06-26 09:49:39 -07:00
Viktor Malik e91370550f bpf: Add kfuncs for read-only string operations
String operations are commonly used so this exposes the most common ones
to BPF programs. For now, we limit ourselves to operations which do not
copy memory around.

Unfortunately, most in-kernel implementations assume that strings are
%NUL-terminated, which is not necessarily true, and therefore we cannot
use them directly in the BPF context. Instead, we open-code them using
__get_kernel_nofault instead of plain dereference to make them safe and
limit the strings length to XATTR_SIZE_MAX to make sure the functions
terminate. When __get_kernel_nofault fails, functions return -EFAULT.
Similarly, when the size bound is reached, the functions return -E2BIG.
In addition, we return -ERANGE when the passed strings are outside of
the kernel address space.

Note that thanks to these dynamic safety checks, no other constraints
are put on the kfunc args (they are marked with the "__ign" suffix to
skip any verifier checks for them).

All of the functions return integers, including functions which normally
(in kernel or libc) return pointers to the strings. The reason is that
since the strings are generally treated as unsafe, the pointers couldn't
be dereferenced anyways. So, instead, we return an index to the string
and let user decide what to do with it. This also nicely fits with
returning various error codes when necessary (see above).

Suggested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Viktor Malik <vmalik@redhat.com>
Link: https://lore.kernel.org/r/4b008a6212852c1b056a413f86e3efddac73551c.1750917800.git.vmalik@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-06-26 09:44:45 -07:00
Anton Protopopov d83caf7c8d bpf: add btf_type_is_i{32,64} helpers
There are places in BPF code which check if a BTF type is an integer
of particular size. This code can be made simpler by using helpers.
Add new btf_type_is_i{32,64} helpers, and simplify code in a few
files. (Suggested by Eduard for a patch which copy-pasted such a
check [1].)

  v1 -> v2:
    * export less generic helpers (Eduard)
    * make subject less generic than in [v1] (Eduard)

[1] https://lore.kernel.org/bpf/7edb47e73baa46705119a23c6bf4af26517a640f.camel@gmail.com/
[v1] https://lore.kernel.org/bpf/20250624193655.733050-1-a.s.protopopov@gmail.com/

Suggested-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250625151621.1000584-1-a.s.protopopov@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-06-25 15:15:49 -07:00