====================
bpf: fix end-of-list detection in cgroup_storage_get_next_key()
list_next_entry() never returns NULL, so the NULL check in
cgroup_storage_get_next_key() is dead code. When iterating past the last
element, the function reads storage->key from a bogus pointer that aliases
internal map fields and copies the result to userspace.
Patch 1 replaces the NULL check with list_entry_is_head() so the function
correctly returns -ENOENT when there are no more entries.
Patch 2 adds a selftest to cover this corner case, as suggested by Sun Jian
and Paul Chaignon.
Weiming Shi [Fri, 3 Apr 2026 13:29:51 +0000 (21:29 +0800)]
selftests/bpf: add get_next_key boundary test for cgroup_storage
Verify that bpf_map__get_next_key() correctly returns -ENOENT when
called on the last (and only) key in a cgroup_storage map. Before the
fix in the previous patch, this would succeed with bogus key data
instead of failing.
Suggested-by: Paul Chaignon <paul.chaignon@gmail.com> Signed-off-by: Weiming Shi <bestswngs@gmail.com> Acked-by: Paul Chaignon <paul.chaignon@gmail.com> Link: https://lore.kernel.org/r/20260403132951.43533-3-bestswngs@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Weiming Shi [Fri, 3 Apr 2026 13:29:50 +0000 (21:29 +0800)]
bpf: fix end-of-list detection in cgroup_storage_get_next_key()
list_next_entry() never returns NULL -- when the current element is the
last entry it wraps to the list head via container_of(). The subsequent
NULL check is therefore dead code and get_next_key() never returns
-ENOENT for the last element, instead reading storage->key from a bogus
pointer that aliases internal map fields and copying the result to
userspace.
Replace it with list_entry_is_head() so the function correctly returns
-ENOENT when there are no more entries.
Fixes: de9cbbaadba5 ("bpf: introduce cgroup storage maps") Reported-by: Xiang Mei <xmei5@asu.edu> Signed-off-by: Weiming Shi <bestswngs@gmail.com> Reviewed-by: Sun Jian <sun.jian.kdev@gmail.com> Acked-by: Paul Chaignon <paul.chaignon@gmail.com> Link: https://lore.kernel.org/r/20260403132951.43533-2-bestswngs@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
====================
bpf: Fix torn writes in non-prealloc htab with BPF_F_LOCK
A torn write issue was reported in htab_map_update_elem() with
BPF_F_LOCK on hash maps. The BPF_F_LOCK fast path performs
a lockless lookup and copies the value under the element's embedded
spin_lock. A concurrent delete can free the element via
bpf_mem_cache_free(), which allows immediate reuse. When
alloc_htab_elem() recycles the same memory, it writes the value with
plain copy_map_value() without taking the spin_lock, racing with the
stale lock holder and producing torn writes.
Patch 1 fixes alloc_htab_elem() to use copy_map_value_locked() when
BPF_F_LOCK is set.
Patch 2 adds a selftest that reliably detects the torn writes on an
unpatched kernel.
selftests/bpf: Add torn write detection test for htab BPF_F_LOCK
Add a consistency subtest to htab_reuse that detects torn writes
caused by the BPF_F_LOCK lockless update racing with element
reallocation in alloc_htab_elem().
The test uses three thread roles started simultaneously via a pipe:
- locked updaters: BPF_F_LOCK|BPF_EXIST in-place updates
- delete+update workers: delete then BPF_ANY|BPF_F_LOCK insert
- locked readers: BPF_F_LOCK lookup checking value consistency
bpf: Use copy_map_value_locked() in alloc_htab_elem() for BPF_F_LOCK
When a BPF_F_LOCK update races with a concurrent delete, the freed
element can be immediately recycled by alloc_htab_elem(). The fast path
in htab_map_update_elem() performs a lockless lookup and then calls
copy_map_value_locked() under the element's spin_lock. If
alloc_htab_elem() recycles the same memory, it overwrites the value
with plain copy_map_value(), without taking the spin_lock, causing
torn writes.
Use copy_map_value_locked() when BPF_F_LOCK is set so the new element's
value is written under the embedded spin_lock, serializing against any
stale lock holders.
v1->v2:
. fixed bugs spotted by Eduard, Mykyta, claude and gemini
. fixed selftests that were failing in unpriv
. gemini(sashiko) found several precision improvements in patch 6,
but they made no difference in real programs.
v1: https://lore.kernel.org/bpf/20260401021635.34636-1-alexei.starovoitov@gmail.com/
First 6 prep patches for static stack liveness.
. do src/dst_reg validation early and remove defensive checks
. sort subprog in topo order. We wanted to do this long ago
to process global subprogs this way and in other cases.
. Add constant folding pass that computes map_ptr, subprog_idx,
loads from readonly maps, and other constants that fit into 32-bit
. Use these constants to eliminate dead code. Replace predicted
conditional branches with "jmp always". That reduces JIT prog size.
. Add two helpers that return access size from their arguments.
====================
bpf: Add helper and kfunc stack access size resolution
The static stack liveness analysis needs to know how many bytes a
helper or kfunc accesses through a stack pointer argument, so it can
precisely mark the affected stack slots as stack 'def' or 'use'.
Add bpf_helper_stack_access_bytes() and bpf_kfunc_stack_access_bytes()
which resolve the access size for a given call argument.
bpf: Add bpf_compute_const_regs() and bpf_prune_dead_branches() passes
Add two passes before the main verifier pass:
bpf_compute_const_regs() is a forward dataflow analysis that tracks
register values in R0-R9 across the program using fixed-point
iteration in reverse postorder. Each register is tracked with
a six-state lattice:
At merge points, if two paths produce the same state and value for
a register, it stays; otherwise it becomes UNKNOWN.
The analysis handles:
- MOV, ADD, SUB, AND with immediate or register operands
- LD_IMM64 for plain constants, map FDs, map values, and subprogs
- LDX from read-only maps: constant-folds the load by reading the
map value directly via bpf_map_direct_read()
Results that fit in 32 bits are stored per-instruction in
insn_aux_data and bitmasks.
bpf_prune_dead_branches() uses the computed constants to evaluate
conditional branches. When both operands of a conditional jump are
known constants, the branch outcome is determined statically and the
instruction is rewritten to an unconditional jump.
The CFG postorder is then recomputed to reflect new control flow.
This eliminates dead edges so that subsequent liveness analysis
doesn't propagate through dead code.
Also add runtime sanity check to validate that precomputed
constants match the verifier's tracked state.
selftests/bpf: Add tests for subprog topological ordering
Add few tests for topo sort:
- linear chain: main -> A -> B
- diamond: main -> A, main -> B, A -> C, B -> C
- mixed global/static: main -> global -> static leaf
- shared callee: main -> leaf, main -> global -> leaf
- duplicate calls: main calls same subprog twice
- no calls: single subprog
bpf: Sort subprogs in topological order after check_cfg()
Add a pass that sorts subprogs in topological order so that iterating
subprog_topo_order[] walks leaf subprogs first, then their callers.
This is computed as a DFS post-order traversal of the CFG.
The pass runs after check_cfg() to ensure the CFG has been validated
before traversing and after postorder has been computed to avoid
walking dead code.
Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Pull bpf fixes from Alexei Starovoitov:
- Fix register equivalence for pointers to packet (Alexei Starovoitov)
- Fix incorrect pruning due to atomic fetch precision tracking (Daniel
Borkmann)
- Fix grace period wait for bpf_link-ed tracepoints (Kumar Kartikeya
Dwivedi)
- Fix use-after-free of sockmap's sk->sk_socket (Kuniyuki Iwashima)
- Reject direct access to nullable PTR_TO_BUF pointers (Qi Tang)
- Reject sleepable kprobe_multi programs at attach time (Varun R
Mallya)
* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
selftests/bpf: Add more precision tracking tests for atomics
bpf: Fix incorrect pruning due to atomic fetch precision tracking
bpf: Reject sleepable kprobe_multi programs at attach time
bpf: reject direct access to nullable PTR_TO_BUF pointers
bpf: sockmap: Fix use-after-free of sk->sk_socket in sk_psock_verdict_data_ready().
bpf: Fix grace period wait for tracepoint bpf_link
bpf: Fix regsafe() for pointers to packet
====================
Fix invariant violations and improve branch detection
This patchset fixes invariant violations on register bounds. These
invariant violations cause a warning and happen when reg_bounds_sync is
trying to refine register bounds while walking an impossible branch.
This patchset takes this situation as an opportunity to improve
verification performance. That is, the verifier will use the invariant
violations as a signal that a branch cannot be taken and process it as
dead code.
This patchset implements this approach and covers it in selftests with
a new invariant violation case. Some of the logic in reg_bounds_sync
likely acts as a duplicate with logic from is_scalar_branch_taken. This
patchset does not attempt to remove superfluous logic from
is_scalar_branch_taken and leaves it to a future patchset (ex. once
syzbot has confirmed that all invariant violations are fixed).
In the future, there is also a potential opportunity to simplify
existing logic by merging reg_bounds_sync and range_bounds_violation
(have reg_bounds_sync error out on invariant violation). That is
however not needed to fix invariant violation, which we focus on in
this patchset.
Changes in v3:
- Rename and refactor the helper functions checking for tnum-related
invariant violations (Mykyta).
- Small changes to comment style in verifier changes and new selftest
(Mykyta).
- Rebased.
Changes in v2:
- Moved tmp registers to env in preparatory commit (Eduard).
- Updated reg_bounds_sync to bail out in case of ill-formed
registers, thus avoiding one set of invariant violation checks in
simulate_both_branches_taken (Eduard).
- Drop the Fixes tag to avoid misleading backporters (Shung-Hsi).
- Improve wording of commit descriptions (Shung-Hsi, Hari).
- Fix error in code comments (AI bot).
- Rebased.
====================
Paul Chaignon [Thu, 2 Apr 2026 15:12:48 +0000 (17:12 +0200)]
selftests/bpf: Remove invariant violation flags
With the changes to the verifier in previous commits, we're not
expecting any invariant violations anymore. We should therefore always
enable BPF_F_TEST_REG_INVARIANTS to fail on invariant violations. Turns
out that's already the case and we've been explicitly setting this flag
in selftests when it wasn't necessary. This commit removes those flags
from selftests, which should hopefully make clearer that it's always
enabled.
Paul Chaignon [Thu, 2 Apr 2026 15:11:41 +0000 (17:11 +0200)]
selftests/bpf: Cover invariant violation case from syzbot
This patch adds a selftest for the change in the previous patch. The
selftest is derived from a syzbot reproducer from [1] (among the 22
reproducers on that page, only 4 still reproduced on latest bpf tree,
all being small variants of the same invariant violation).
The test case failure without the previous patch is shown below.
R5 and R7 are prepared such that their tnums intersection results in a
known constant but that constant isn't within R7's u32 bounds.
is_branch_taken isn't able to detect this case today, so the verifier
walks the impossible fallthrough branch. After regs_refine_cond_op and
reg_bounds_sync refine R5 on the assumption that the branch is taken,
the impossibility becomes apparent and results in an invariant violation
for R5: umin32 is greater than umax32.
The previous patch fixes this by using regs_refine_cond_op and
reg_bounds_sync in is_branch_taken to detect the impossible branch. The
fallthrough branch is therefore correctly detected as dead code.
bpf: Simulate branches to prune based on range violations
This patch fixes the invariant violations that can happen after we
refine ranges & tnum based on an incorrectly-detected branch condition.
For example, the branch is always true, but we miss it in
is_branch_taken; we then refine based on the branch being false and end
up with incoherent ranges (e.g. umax < umin).
To avoid this, we can simulate the refinement on both branches. More
specifically, this patch simulates both branches taken using
regs_refine_cond_op and reg_bounds_sync. If the resulting register
states are ill-formed on one of the branches, is_branch_taken can mark
that branch as "never taken".
On a more formal note, we can deduce a branch is not taken when
regs_refine_cond_op or reg_bounds_sync returns an ill-formed state
because the branch operators are sound (verified with Agni [1]).
Soundness means that the verifier is guaranteed to produce sound
outputs on the taken branches. On the non-taken branch (explored
because of imprecision in the bounds), the verifier is free to produce
any output. We use ill-formedness as a signal that the branch is dead
and prune that branch.
This patch moves the refinement logic for both branches from
reg_set_min_max to their own function, simulate_both_branches_taken,
which is called from is_scalar_branch_taken. As a result,
reg_set_min_max now only runs sanity checks and has been renamed to
reg_bounds_sanity_check_branches to reflect that.
We have had five patches fixing specific cases of invariant violations
in the past, all added with selftests:
- commit fbc7aef517d8 ("bpf: Fix u32/s32 bounds when ranges cross
min/max boundary")
- commit efc11a667878 ("bpf: Improve bounds when tnum has a single
possible value")
- commit f41345f47fb2 ("bpf: Use tnums for JEQ/JNE is_branch_taken
logic")
- commit 00bf8d0c6c9b ("bpf: Improve bounds when s64 crosses sign
boundary")
- commit 6279846b9b25 ("bpf: Forget ranges when refining tnum after
JSET")
To confirm that this patch addresses all invariant violations, we have
also reverted those five commits and verified that their related
selftests don't cause any invariant violation warnings anymore. Those
selftests still fail but only because of misdetected branches or
less-precise bounds than expected. This demonstrates that the current
patch is enough to avoid the invariant violation warning AND that the
previous five patches are still useful to improve branch detection.
In addition to the selftests, this change was also tested with the
Cilium complexity test suite: all programs were successfully loaded and
it didn't change the number of processed instructions.
bpf: Exit early if reg_bounds_sync gets invalid inputs
In the subsequent commit, to prune dead branches we will rely on
detecting ill-formed ranges using range_bounds_violations()
(e.g., umin > umax) after refining register bounds using
regs_refine_cond_op().
However, reg_bounds_sync() can sometimes "repair" ill-formed bounds,
potentially masking a violation that was produced by
regs_refine_cond_op().
This commit modifies reg_bounds_sync() to exit early if an invariant
violation is already present in the input.
This ensures ill-formed reg_states remain ill-formed after
reg_bounds_sync(), allowing simulate_both_branches_taken() to correctly
identify dead branches with a single check to range_bounds_violation().
Suggested-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Harishankar Vishwanathan <harishankar.vishwanathan@gmail.com> Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com> Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/73127d628841c59cb7423d6bdcd204bf90bcdc80.1775142354.git.paul.chaignon@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Paul Chaignon [Thu, 2 Apr 2026 15:09:15 +0000 (17:09 +0200)]
bpf: Use bpf_verifier_env buffers for reg_set_min_max
In a subsequent patch, the regs_refine_cond_op and reg_bounds_sync
functions will be called in is_branch_taken instead of reg_set_min_max,
to simulate each branch's outcome. Since they will run before we branch
out, these two functions will need to work on temporary registers for
the two branches.
This refactoring patch prepares for that change, by introducing the
temporary registers on bpf_verifier_env and using them in
reg_set_min_max.
This change also allows us to save one fake_reg slot as we don't need to
allocate an additional temporary buffer in case of a BPF_K condition.
Finally, you may notice that this patch removes the check for
"false_reg1 == false_reg2" in reg_set_min_max. That check was introduced
in commit d43ad9da8052 ("bpf: Skip bounds adjustment for conditional
jumps on same scalar register") to avoid an invariant violation. Given
that "env->false_reg1 == env->false_reg2" doesn't make sense and
invariant violations are addressed in a subsequent commit, this patch
just removes the check.
Merge tag 'v7.0-p4' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto fixes from Herbert Xu:
- Add missing async markers to tegra
- Fix long hmac key DMA handling in caam
- Fix spurious ENOSPC errors in deflate
- Fix SG chaining in af_alg
- Do not use in-place process in algif_aead
- Fix out-of-place destination overflow in authencesn
* tag 'v7.0-p4' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: authencesn - Do not place hiseq at end of dst for out-of-place decryption
crypto: algif_aead - Revert to operating out-of-place
crypto: af-alg - fix NULL pointer dereference in scatterwalk
crypto: deflate - fix spurious -ENOSPC
crypto: caam - fix overflow on long hmac keys
crypto: caam - fix DMA corruption on long hmac keys
crypto: tegra - Add missing CRYPTO_ALG_ASYNC
====================
Task local data bug fixes and improvement
This patchset fixed three task local data bugs, improved the
memory allocation code, and dropped unnecessary TLD_READ_ONCE. Please
find the detail in each patch's commit msg.
One thing worth mentioning is that Patch 3 allows us to renable task
local data selftests as the library now always calls aligned_alloc()
with size matching alignment under default configuration.
Amery Hung [Tue, 31 Mar 2026 21:35:55 +0000 (14:35 -0700)]
selftests/bpf: Improve task local data documentation and fix potential memory leak
If TLD_FREE_DATA_ON_THREAD_EXIT is not enabled in a translation unit
that calls __tld_create_key() first, another translation unit that
enables it will not get the auto cleanup feature as pthread key is only
created once when allocation metadata. Fix it by always try to create
the pthread key when __tld_create_key() is called.
Also improve the documentation:
- Discourage user from using different options in different translation
units
- Specify calling tld_free() before thread exit as undefined behavior
Amery Hung [Tue, 31 Mar 2026 21:35:54 +0000 (14:35 -0700)]
selftests/bpf: Remove TLD_READ_ONCE() in the user space header
TLD_READ_ONCE() is redundant as the only reference passed to it is
defined as _Atomic. The load is guaranteed to be atomic in C11 standard
(6.2.6.1). Drop the macro.
Amery Hung [Tue, 31 Mar 2026 21:35:53 +0000 (14:35 -0700)]
selftests/bpf: Make sure TLD_DEFINE_KEY runs first
Without specifying constructor priority of the hidden constructor
function defined by TLD_DEFINE_KEY, __tld_create_key(..., dyn_data =
false) may run after tld_get_data() called from other constructors.
Threads calling tld_get_data() before __tld_create_key(..., dyn_data
= false) will not allocate enough memory for all TLDs and later result
in OOB access. Therefore, set it to the lowest value available to
users. Note that lower means higher priority and 0-100 is reserved to
the compiler.
Simplify data allocation by always using aligned_alloc() and passing
size_pot, size rounded up to the closest power of two to alignment.
Currently, aligned_alloc(page_size, size) is only intended to be used
with memory allocators that can fulfill the request without rounding
size up to page_size to conserve memory. This is enabled by defining
TLD_DATA_USE_ALIGNED_ALLOC. The reason to align to page_size is due to
the limitation of UPTR where only a page can be pinned to the kernel.
Otherwise, malloc(size * 2) is used to allocate memory for data.
However, we don't need to call aligned_alloc(page_size, size) to get
a contiguous memory of size bytes within a page. aligned_alloc(size_pot,
...) will also do the trick. Therefore, just use aligned_alloc(size_pot,
...) universally.
As for the size argument, create a new option,
TLD_DONT_ROUND_UP_DATA_SIZE, to specify not rounding up the size.
This preserves the current TLD_DATA_USE_ALIGNED_ALLOC behavior, allowing
memory allocators with low overhead aligned_alloc() to not waste memory.
To enable this, users need to make sure it is not an undefined behavior
for the memory allocator to have size not being an integral multiple of
alignment.
Compared to the current implementation, !TLD_DATA_USE_ALIGNED_ALLOC
used to always waste size-byte of memory due to malloc(size * 2).
Now the worst case becomes size - 1 and the best case is 0 when the size
is already a power of two.
Amery Hung [Tue, 31 Mar 2026 21:35:51 +0000 (14:35 -0700)]
selftests/bpf: Fix task_local_data data allocation size
Currently, when allocating memory for data, size of tld_data_u->start
is not taken into account. This may cause OOB access. Fixed it by adding
the non-flexible array part of tld_data_u.
Besides, explicitly align tld_data_u->data to 8 bytes in case some
fields are added before data in the future. It could break the
assumption that every data field is 8 byte aligned and
sizeof(tld_data_u) will no longer be equal to
offsetof(struct tld_data_u, data), which we use interchangeably.
====================
libbpf: clarify raw-address single kprobe attach behavior
Today libbpf documents single-kprobe attach through func_name, with an
optional offset. For the PMU-based path, func_name = NULL with an
absolute address in offset already works as well, but that is not
described in the API.
This patchset clarifies this behavior. First commit fixes kprobe
and uprobe attach error handling to use direct error codes. Next adds
kprobe API comments for the raw-address form and rejects it explicitly
for legacy tracefs/debugfs kprobes. Last adds PERF and LINK selftests
for the raw-address form, and checks that LEGACY rejects it.
---
Changes in v7:
- Change selftest line wrapping and assertions
Changes in v6:
- Split the kprobe/uprobe direct error-code fix into a separate patch
Changes in v5:
- Add kprobe API docs, use -EOPNOTSUPP, and switch selftests to LIBBPF_OPTS
Changes in v4:
- Inline raw-address error formatting and remove the probe_target buffer
Changes in v3:
- Drop bpf_kprobe_opts.addr and reuse offset when func_name is NULL
- Make legacy tracefs/debugfs kprobes reject the raw-address form
- Update selftests to cover PERF/LINK raw-address attach and LEGACY reject
Changes in v2:
- Fix line wrapping and indentation
====================
Hoyeon Lee [Wed, 1 Apr 2026 14:29:31 +0000 (23:29 +0900)]
selftests/bpf: Add test for raw-address single kprobe attach
Currently, attach_probe covers manual single-kprobe attaches by
func_name, but not the raw-address form that the PMU-based
single-kprobe path can accept.
This commit adds PERF and LINK raw-address coverage. It resolves
SYS_NANOSLEEP_KPROBE_NAME through kallsyms, passes the absolute address
in bpf_kprobe_opts.offset with func_name = NULL, and verifies that
kprobe and kretprobe are still triggered. It also verifies that LEGACY
rejects the same form.
Hoyeon Lee [Wed, 1 Apr 2026 14:29:30 +0000 (23:29 +0900)]
libbpf: Clarify raw-address single kprobe attach behavior
bpf_program__attach_kprobe_opts() documents single-kprobe attach
through func_name, with an optional offset. For the PMU-based path,
func_name = NULL with an absolute address in offset already works as
well, but that is not described in the API.
This commit clarifies this existing non-legacy behavior. For PMU-based
attach, callers can use func_name = NULL with an absolute address in
offset as the raw-address form. For legacy tracefs/debugfs kprobes,
reject this form explicitly.
Hoyeon Lee [Wed, 1 Apr 2026 14:29:29 +0000 (23:29 +0900)]
libbpf: Use direct error codes for kprobe/uprobe attach
perf_event_open_probe() and perf_event_{k,u}probe_open_legacy() helpers
are returning negative error codes directly on failure. This commit
changes bpf_program__attach_{k,u}probe_opts() to use those return
values directly instead of re-reading possibly changed errno.
Align bpf_program__clone() with bpf_object_load_prog() by gating
BTF func/line info on FEAT_BTF_FUNC kernel support, and resolve
caller-provided prog_btf_fd before checking obj->btf so that callers
with their own BTF can use clone() even when the object has no BTF
loaded.
While at it, treat func_info and line_info fields as atomic groups
to prevent mismatches between pointer and count from different sources.
Merge tag 'for-7.0-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fix from David Sterba:
"One more fix for a potential extent tree corruption due to an
unexpected error value.
When the search for an extent item failed, it under some circumstances
was reported as a success to the caller"
* tag 'for-7.0-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: fix incorrect return value after changing leaf in lookup_extent_data_ref()
Daniel Borkmann [Tue, 31 Mar 2026 22:20:20 +0000 (00:20 +0200)]
selftests/bpf: Add more precision tracking tests for atomics
Add verifier precision tracking tests for BPF atomic fetch operations.
Validate that backtrack_insn correctly propagates precision from the
fetch dst_reg to the stack slot for {fetch_add,xchg,cmpxchg} atomics.
For the first two src_reg gets the old memory value, and for the last
one r0. The fetched register is used for pointer arithmetic to trigger
backtracking. Also add coverage for fetch_{or,and,xor} flavors which
exercises the bitwise atomic fetch variants going through the same
insn->imm & BPF_FETCH check but with different imm values.
Add dual-precision regression tests for fetch_add and cmpxchg where
both the fetched value and a reread of the same stack slot are tracked
for precision. After the atomic operation, the stack slot is STACK_MISC,
so the ldx does not set INSN_F_STACK_ACCESS. These tests verify that
stack precision propagates solely through the atomic fetch's load side.
Add map-based tests for fetch_add and cmpxchg which validate that non-
stack atomic fetch completes precision tracking without falling back
to mark_all_scalars_precise. Lastly, add 32-bit variants for {fetch_add,
cmpxchg} on map values to cover the second valid atomic operand size.
Daniel Borkmann [Tue, 31 Mar 2026 22:20:19 +0000 (00:20 +0200)]
bpf: Fix incorrect pruning due to atomic fetch precision tracking
When backtrack_insn encounters a BPF_STX instruction with BPF_ATOMIC
and BPF_FETCH, the src register (or r0 for BPF_CMPXCHG) also acts as
a destination, thus receiving the old value from the memory location.
The current backtracking logic does not account for this. It treats
atomic fetch operations the same as regular stores where the src
register is only an input. This leads the backtrack_insn to fail to
propagate precision to the stack location, which is then not marked
as precise!
Later, the verifier's path pruning can incorrectly consider two states
equivalent when they differ in terms of stack state. Meaning, two
branches can be treated as equivalent and thus get pruned when they
should not be seen as such.
Fix it as follows: Extend the BPF_LDX handling in backtrack_insn to
also cover atomic fetch operations via is_atomic_fetch_insn() helper.
When the fetch dst register is being tracked for precision, clear it,
and propagate precision over to the stack slot. For non-stack memory,
the precision walk stops at the atomic instruction, same as regular
BPF_LDX. This covers all fetch variants.
Merge tag 'net-7.0-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"With fixes from wireless, bluetooth and netfilter included we're back
to each PR carrying 30%+ more fixes than in previous era.
The good news is that so far none of the "extra" fixes are themselves
causing real regressions. Not sure how much comfort that is.
Current release - fix to a fix:
- netdevsim: fix build if SKB_EXTENSIONS=n
- eth: stmmac: skip VLAN restore when VLAN hash ops are missing
Previous releases - regressions:
- wifi: iwlwifi: mvm: don't send a 6E related command when
not supported
Previous releases - always broken:
- some info leak fixes
- add missing clearing of skb->cb[] on ICMP paths from tunnels
- ipv6:
- flowlabel: defer exclusive option free until RCU teardown
- avoid overflows in ip6_datagram_send_ctl()
- mpls: add seqcount to protect platform_labels from OOB access
- bridge: improve safety of parsing ND options
- bluetooth: fix leaks, overflows and races in hci_sync
- netfilter: add more input validation, some to address bugs directly
some to prevent exploits from cooking up broken configurations
- wifi:
- ath: avoid poor performance due to stopping the wrong
aggregation session
- virt_wifi: remove SET_NETDEV_DEV to avoid use-after-free
- eth:
- fec: fix the PTP periodic output sysfs interface
- enetc: safely reinitialize TX BD ring when it has unsent frames"
* tag 'net-7.0-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (95 commits)
eth: fbnic: Increase FBNIC_QUEUE_SIZE_MIN to 64
ipv6: avoid overflows in ip6_datagram_send_ctl()
net: hsr: fix VLAN add unwind on slave errors
net: hsr: serialize seq_blocks merge across nodes
vsock: initialize child_ns_mode_locked in vsock_net_init()
selftests/tc-testing: add tests for cls_fw and cls_flow on shared blocks
net/sched: cls_flow: fix NULL pointer dereference on shared blocks
net/sched: cls_fw: fix NULL pointer dereference on shared blocks
net/x25: Fix overflow when accumulating packets
net/x25: Fix potential double free of skb
bnxt_en: Restore default stat ctxs for ULP when resource is available
bnxt_en: Don't assume XDP is never enabled in bnxt_init_dflt_ring_mode()
bnxt_en: Refactor some basic ring setup and adjustment logic
net/mlx5: Fix switchdev mode rollback in case of failure
net/mlx5: Avoid "No data available" when FW version queries fail
net/mlx5: lag: Check for LAG device before creating debugfs
net: macb: properly unregister fixed rate clocks
net: macb: fix clk handling on PCI glue driver removal
virtio_net: clamp rss_max_key_size to NETDEV_RSS_KEY_LEN
net/sched: sch_netem: fix out-of-bounds access in packet corruption
...
Merge tag 'iommu-fixes-v7.0-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux
Pull iommu fixes from Joerg Roedel:
- IOMMU-PT related compile breakage in for AMD driver
- IOTLB flushing behavior when unmapped region is larger than requested
due to page-sizes
- Fix IOTLB flush behavior with empty gathers
* tag 'iommu-fixes-v7.0-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux:
iommupt/amdv1: mark amdv1pt_install_leaf_entry as __always_inline
iommupt: Fix short gather if the unmap goes into a large mapping
iommu: Do not call drivers for empty gathers
bpf: Reject sleepable kprobe_multi programs at attach time
kprobe.multi programs run in atomic/RCU context and cannot sleep.
However, bpf_kprobe_multi_link_attach() did not validate whether the
program being attached had the sleepable flag set, allowing sleepable
helpers such as bpf_copy_from_user() to be invoked from a non-sleepable
context.
This causes a "sleeping function called from invalid context" splat:
BUG: sleeping function called from invalid context at ./include/linux/uaccess.h:169
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1787, name: sudo
preempt_count: 1, expected: 0
RCU nest depth: 2, expected: 0
Fix this by rejecting sleepable programs early in
bpf_kprobe_multi_link_attach(), before any further processing.
Fixes: 0dcac2725406 ("bpf: Add multi kprobe link") Signed-off-by: Varun R Mallya <varunrmallya@gmail.com> Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Acked-by: Leon Hwang <leon.hwang@linux.dev> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20260401191126.440683-1-varunrmallya@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Merge tag 'sound-7.0-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"People have been so busy for hunting and we're still getting more
changes than wished for, but it doesn't look too scary; almost all
changes are device-specific small fixes.
I guess it's rather a casual bump, and no more Easter eggs are left
for 7.0 (hopefully)...
- Fixes for the recent regression on ctxfi driver
- Fix missing INIT_LIST_HEAD() for ASoC card_aux_list
- Usual HD- and USB-audio, and ASoC AMD quirk updates
- ASoC fixes for AMD and Intel"
* tag 'sound-7.0-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (24 commits)
ASoC: amd: ps: Fix missing leading zeros in subsystem_device SSID log
ALSA: usb-audio: Exclude Scarlett 2i2 1st Gen (8016) from SKIP_IFACE_SETUP
ALSA: hda/realtek: add quirk for Acer Swift SFG14-73
ALSA: hda/realtek: Add quirk for Lenovo Yoga Pro 7 14IMH9
ASoC: Intel: boards: fix unmet dependency on PINCTRL
ASoC: Intel: ehl_rt5660: Use the correct rtd->dev device in hw_params
ALSA: ctxfi: Don't enumerate SPDIF1 at DAIO initialization
ALSA: hda/realtek: Add quirk for Lenovo Yoga Slim 7 14AKP10
ALSA: hda/realtek: add quirk for HP Laptop 15-fc0xxx
ASoC: ep93xx: Fix unchecked clk_prepare_enable() and add rollback on failure
ASoC: soc-core: call missing INIT_LIST_HEAD() for card_aux_list
ALSA: hda/realtek: Add quirk for Samsung Book2 Pro 360 (NP950QED)
ASoC: amd: yc: Add DMI entry for HP Laptop 15-fc0xxx
ASoC: amd: yc: Add DMI quirk for ASUS Vivobook Pro 16X OLED M7601RM
ALSA: hda/realtek: Add quirk for ASUS ROG Strix SCAR 15
ALSA: usb-audio: Exclude Scarlett Solo 1st Gen from SKIP_IFACE_SETUP
ALSA: caiaq: fix stack out-of-bounds read in init_card
ALSA: ctxfi: Check the error for index mapping
ALSA: ctxfi: Fix missing SPDIFI1 index handling
ALSA: hda/realtek: add quirk for HP Victus 15-fb0xxx
...
Merge tag 'auxdisplay-v7.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/andy/linux-auxdisplay
Pull auxdisplay fixes from Andy Shevchenko:
- Fix NULL dereference in linedisp_release()
- Fix ht16k33 DT bindings to avoid warnings
- Handle errors in I²C transfers in lcd2s driver
* tag 'auxdisplay-v7.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/andy/linux-auxdisplay:
auxdisplay: line-display: fix NULL dereference in linedisp_release
auxdisplay: lcd2s: add error handling for i2c transfers
dt-bindings: auxdisplay: ht16k33: Use unevaluatedProperties to fix common property warning
====================
bpf: Migrate bpf_task_work and file dynptr to kmalloc_nolock
Now that kmalloc can be used from NMI context via kmalloc_nolock(),
migrate BPF internal allocations away from bpf_mem_alloc to use the
standard slab allocator.
Use kfree_rcu() for deferred freeing, which waits for a regular RCU
grace period before the memory is reclaimed. Sleepable BPF programs
hold rcu_read_lock_trace but not regular rcu_read_lock, so patch 1
adds explicit rcu_read_lock/unlock around the pointer-to-refcount
window to prevent kfree_rcu from freeing memory while a sleepable
program is still between reading the pointer and acquiring a
reference.
Patch 1 migrates bpf_task_work_ctx from bpf_mem_alloc/bpf_mem_free to
kmalloc_nolock/kfree_rcu.
Patch 2 migrates bpf_dynptr_file_impl from bpf_mem_alloc/bpf_mem_free
to kmalloc_nolock/kfree.
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
---
Changes in v2:
- Switch to scoped_guard in patch 1 (Kumar)
- Remove rcu gp wait in patch 2 (Kumar)
- Defer to irq_work when irqs disabled in patch 1
- use bpf_map_kmalloc_nolock() for bpf_task_work
- use kmalloc_nolock() for file dynptr
- Link to v1: https://lore.kernel.org/all/20260325-kmalloc_special-v1-0-269666afb1ea@meta.com/
====================
Mykyta Yatsenko [Mon, 30 Mar 2026 22:27:57 +0000 (15:27 -0700)]
bpf: Migrate dynptr file to kmalloc_nolock
Replace bpf_mem_alloc/bpf_mem_free with kmalloc_nolock/kfree_nolock for
bpf_dynptr_file_impl, continuing the migration away from bpf_mem_alloc
now that kmalloc can be used from NMI context.
freader_cleanup() runs before kfree_nolock() while the dynptr still
holds exclusive access, so plain kfree_nolock() is safe — no concurrent
readers can access the object.
Mykyta Yatsenko [Mon, 30 Mar 2026 22:27:56 +0000 (15:27 -0700)]
bpf: Migrate bpf_task_work to kmalloc_nolock
Replace bpf_mem_alloc/bpf_mem_free with
kmalloc_nolock/kfree_rcu for bpf_task_work_ctx.
Replace guard(rcu_tasks_trace)() with guard(rcu)() in
bpf_task_work_irq(). The function only accesses ctx struct members
(not map values), so tasks trace protection is not needed - regular
RCU is sufficient since ctx is freed via kfree_rcu. The guard in
bpf_task_work_callback() remains as tasks trace since it accesses map
values from process context.
Sleepable BPF programs hold rcu_read_lock_trace but not
regular rcu_read_lock. Since kfree_rcu
waits for a regular RCU grace period, the ctx memory can be freed
while a sleepable program is still running. Add scoped_guard(rcu)
around the pointer read and refcount tryget in
bpf_task_work_acquire_ctx to close this race window.
Since kfree_rcu uses call_rcu internally which is not safe from
NMI context, defer destruction via irq_work when irqs are disabled.
For the lost-cmpxchg path the ctx was never published, so
kfree_nolock is safe.
====================
bpf: Fix abuse of kprobe_write_ctx via freplace
The potential issue of kprobe_write_ctx+freplace was mentioned in
"bpf: Disallow !kprobe_write_ctx progs tail-calling kprobe_write_ctx progs" [1].
It is true issue, that the test in patch #2 verifies that kprobe_write_ctx=false
kprobe progs can be abused to modify struct pt_regs via kprobe_write_ctx=true
freplace progs.
When struct pt_regs is modified, bpf_prog_test_run_opts() gets -EFAULT instead
of 0.
Changes:
v2 -> v3:
* Add comment to the rejection of kprobe_write_ctx (per Jiri).
* Use libbpf_get_error() instead of errno in test (per Jiri).
* Collect Acked-by tags from Jiri and Song, thanks.
v2: https://lore.kernel.org/bpf/20260326141718.17731-1-leon.hwang@linux.dev/
v1 -> v2:
* Drop patch #1 in v1, as it wasn't an issue (per Toke).
* Check kprobe_write_ctx value at attach time instead of at load time, to
prevent attaching kprobe_write_ctx=true freplace progs on
kprobe_write_ctx=false kprobe progs (per Gemini/sashiko).
* Move kprobe_write_ctx test code to attach_probe.c and kprobe_write_ctx.c.
v1: https://lore.kernel.org/bpf/20260324150444.68166-1-leon.hwang@linux.dev/
====================
Leon Hwang [Tue, 31 Mar 2026 14:53:53 +0000 (22:53 +0800)]
selftests/bpf: Add test to verify the fix of kprobe_write_ctx abuse
Add a test to verify the issue: kprobe_write_ctx can be abused to modify
struct pt_regs of kernel functions via kprobe_write_ctx=true freplace
progs.
Without the fix, the issue is verified:
kprobe_write_ctx=true freplace prog is allowed to attach to
kprobe_write_ctx=false kprobe prog. Then, the first arg of
bpf_fentry_test1 will be set as 0, and bpf_prog_test_run_opts() gets
-EFAULT instead of 0.
With the fix, the issue is rejected at attach time.
Leon Hwang [Tue, 31 Mar 2026 14:53:52 +0000 (22:53 +0800)]
bpf: Fix abuse of kprobe_write_ctx via freplace
uprobe programs are allowed to modify struct pt_regs.
Since the actual program type of uprobe is KPROBE, it can be abused to
modify struct pt_regs via kprobe+freplace when the kprobe attaches to
kernel functions.
For example,
SEC("?kprobe")
int kprobe(struct pt_regs *regs)
{
return 0;
}
freplace_kprobe prog will attach to kprobe prog.
kprobe prog will attach to a kernel function.
Without this patch, when the kernel function runs, its first arg will
always be set as 0 via the freplace_kprobe prog.
To fix the abuse of kprobe_write_ctx=true via kprobe+freplace, disallow
attaching freplace programs on kprobe programs with different
kprobe_write_ctx values.
Fixes: 7384893d970e ("bpf: Allow uprobe program to change context registers") Acked-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Song Liu <song@kernel.org> Signed-off-by: Leon Hwang <leon.hwang@linux.dev> Link: https://lore.kernel.org/r/20260331145353.87606-2-leon.hwang@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>
On systems with 64K pages, RX queues will be wedged if users set the
descriptor count to the current minimum (16). Fbnic fragments large
pages into 4K chunks, and scales down the ring size accordingly. With
64K pages and 16 descriptors, the ring size mask is 0 and will never
be filled.
32 descriptors is another special case that wedges the RX rings.
Internally, the rings track pages for the head/tail pointers, not page
fragments. So with 32 descriptors, there's only 1 usable page as one
ring slot is kept empty to disambiguate between an empty/full ring.
As a result, the head pointer never advances and the HW stalls after
consuming 16 page fragments.
Eric Dumazet [Wed, 1 Apr 2026 15:47:21 +0000 (15:47 +0000)]
ipv6: avoid overflows in ip6_datagram_send_ctl()
Yiming Qian reported :
<quote>
I believe I found a locally triggerable kernel bug in the IPv6 sendmsg
ancillary-data path that can panic the kernel via `skb_under_panic()`
(local DoS).
The core issue is a mismatch between:
- a 16-bit length accumulator (`struct ipv6_txoptions::opt_flen`, type
`__u16`) and
- a pointer to the *last* provided destination-options header (`opt->dst1opt`)
when multiple `IPV6_DSTOPTS` control messages (cmsgs) are provided.
- `include/net/ipv6.h`:
- `struct ipv6_txoptions::opt_flen` is `__u16` (wrap possible).
(lines 291-307, especially 298)
- `net/ipv6/datagram.c:ip6_datagram_send_ctl()`:
- Accepts repeated `IPV6_DSTOPTS` and accumulates into `opt_flen`
without rejecting duplicates. (lines 909-933)
- `net/ipv6/ip6_output.c:__ip6_append_data()`:
- Uses `opt->opt_flen + opt->opt_nflen` to compute header
sizes/headroom decisions. (lines 1448-1466, especially 1463-1465)
- `net/ipv6/ip6_output.c:__ip6_make_skb()`:
- Calls `ipv6_push_frag_opts()` if `opt->opt_flen` is non-zero.
(lines 1930-1934)
- `net/ipv6/exthdrs.c:ipv6_push_frag_opts()` / `ipv6_push_exthdr()`:
- Push size comes from `ipv6_optlen(opt->dst1opt)` (based on the
pointed-to header). (lines 1179-1185 and 1206-1211)
1. `opt_flen` is a 16-bit accumulator:
- `include/net/ipv6.h:298` defines `__u16 opt_flen; /* after fragment hdr */`.
2. `ip6_datagram_send_ctl()` accepts *repeated* `IPV6_DSTOPTS` cmsgs
and increments `opt_flen` each time:
- In `net/ipv6/datagram.c:909-933`, for `IPV6_DSTOPTS`:
- It computes `len = ((hdr->hdrlen + 1) << 3);`
- It checks `CAP_NET_RAW` using `ns_capable(net->user_ns,
CAP_NET_RAW)`. (line 922)
- Then it does:
- `opt->opt_flen += len;` (line 927)
- `opt->dst1opt = hdr;` (line 928)
There is no duplicate rejection here (unlike the legacy
`IPV6_2292DSTOPTS` path which rejects duplicates at
`net/ipv6/datagram.c:901-904`).
If enough large `IPV6_DSTOPTS` cmsgs are provided, `opt_flen` wraps
while `dst1opt` still points to a large (2048-byte)
destination-options header.
In the attached PoC (`poc.c`):
- 32 cmsgs with `hdrlen=255` => `len = (255+1)*8 = 2048`
- 1 cmsg with `hdrlen=0` => `len = 8`
- Total increment: `32*2048 + 8 = 65544`, so `(__u16)opt_flen == 8`
- The last cmsg is 2048 bytes, so `dst1opt` points to a 2048-byte header.
3. The transmit path sizes headers using the wrapped `opt_flen`:
- The `IPV6_DSTOPTS` cmsg path requires `CAP_NET_RAW` in the target
netns user namespace (`ns_capable(net->user_ns, CAP_NET_RAW)`).
- Root (or any task with `CAP_NET_RAW`) can trigger this without user
namespaces.
- An unprivileged `uid=1000` user can trigger this if unprivileged
user namespaces are enabled and it can create a userns+netns to obtain
namespaced `CAP_NET_RAW` (the attached PoC does this).
- Local denial of service: kernel BUG/panic (system crash).
- Reproducible with a small userspace PoC.
</quote>
This patch does not reject duplicated options, as this might break
some user applications.
Instead, it makes sure to adjust opt_flen and opt_nflen to correctly
reflect the size of the current option headers, preventing the overflows
and the potential for panics.
This applies to IPV6_DSTOPTS, IPV6_HOPOPTS, and IPV6_RTHDR.
Specifically:
When a new IPV6_DSTOPTS is processed, the length of the old opt->dst1opt
is subtracted from opt->opt_flen before adding the new length.
When a new IPV6_HOPOPTS is processed, the length of the old opt->dst0opt
is subtracted from opt->opt_nflen.
When a new Routing Header (IPV6_RTHDR or IPV6_2292RTHDR) is processed,
the length of the old opt->srcrt is subtracted from opt->opt_nflen.
In the special case within IPV6_2292RTHDR handling where dst1opt is moved
to dst0opt, the length of the old opt->dst0opt is subtracted from
opt->opt_nflen before the new one is added.
Fixes: 333fad5364d6 ("[IPV6]: Support several new sockopt / ancillary data in Advanced API (RFC3542).") Reported-by: Yiming Qian <yimingqian591@gmail.com> Closes: https://lore.kernel.org/netdev/CAL_bE8JNzawgr5OX5m+3jnQDHry2XxhQT5=jThW1zDPtUikRYA@mail.gmail.com/ Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260401154721.3740056-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
====================
net: hsr: fixes for PRP duplication and VLAN unwind
This series addresses two logic bugs in the HSR/PRP implementation
identified during a protocol audit. These are targeted for the 'net'
tree as they fix potential memory corruption and state inconsistency.
The primary change resolves a race condition in the node merging path by
implementing address-based lock ordering. This ensures that concurrent
mutations of sequence blocks do not lead to state corruption or
deadlocks.
An additional fix corrects asymmetric VLAN error unwinding by
implementing a centralized unwind path on slave errors.
====================
Luka Gejak [Wed, 1 Apr 2026 09:22:43 +0000 (11:22 +0200)]
net: hsr: fix VLAN add unwind on slave errors
When vlan_vid_add() fails for a secondary slave, the error path calls
vlan_vid_del() on the failing port instead of the peer slave that had
already succeeded. This results in asymmetric VLAN state across the HSR
pair.
Fix this by switching to a centralized unwind path that removes the VID
from any slave device that was already programmed.
Luka Gejak [Wed, 1 Apr 2026 09:22:42 +0000 (11:22 +0200)]
net: hsr: serialize seq_blocks merge across nodes
During node merging, hsr_handle_sup_frame() walks node_curr->seq_blocks
to update node_real without holding node_curr->seq_out_lock. This
allows concurrent mutations from duplicate registration paths, risking
inconsistent state or XArray/bitmap corruption.
Fix this by locking both nodes' seq_out_lock during the merge.
To prevent ABBA deadlocks, locks are acquired in order of memory
address.
Reviewed-by: Felix Maurer <fmaurer@redhat.com> Fixes: 415e6367512b ("hsr: Implement more robust duplicate discard for PRP") Signed-off-by: Luka Gejak <luka.gejak@linux.dev> Link: https://patch.msgid.link/20260401092243.52121-2-luka.gejak@linux.dev Signed-off-by: Jakub Kicinski <kuba@kernel.org>
vsock: initialize child_ns_mode_locked in vsock_net_init()
The `child_ns_mode_locked` field lives in `struct net`, which persists
across vsock module reloads. When the module is unloaded and reloaded,
`vsock_net_init()` resets `mode` and `child_ns_mode` back to their
default values, but does not reset `child_ns_mode_locked`.
The stale lock from the previous module load causes subsequent writes
to `child_ns_mode` to silently fail: `vsock_net_set_child_mode()` sees
the old lock, skips updating the actual value, and returns success
when the requested mode matches the stale lock. The sysctl handler
reports no error, but `child_ns_mode` remains unchanged.
Steps to reproduce:
$ modprobe vsock
$ echo local > /proc/sys/net/vsock/child_ns_mode
$ cat /proc/sys/net/vsock/child_ns_mode
local
$ modprobe -r vsock
$ modprobe vsock
$ echo local > /proc/sys/net/vsock/child_ns_mode
$ cat /proc/sys/net/vsock/child_ns_mode
global <--- expected "local"
Fix this by initializing `child_ns_mode_locked` to 0 (unlocked) in
`vsock_net_init()`, so the write-once mechanism works correctly after
module reload.
Fixes: 102eab95f025 ("vsock: lock down child_ns_mode as write-once") Reported-by: Jin Liu <jinl@redhat.com> Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> Reviewed-by: Bobby Eshleman <bobbyeshleman@meta.com> Link: https://patch.msgid.link/20260401092153.28462-1-sgarzare@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Xiang Mei [Tue, 31 Mar 2026 05:02:17 +0000 (22:02 -0700)]
selftests/tc-testing: add tests for cls_fw and cls_flow on shared blocks
Regression tests for the shared-block NULL derefs fixed in the previous
two patches:
- fw: attempt to attach an empty fw filter to a shared block and
verify the configuration is rejected with EINVAL.
- flow: create a flow filter on a shared block without a baseclass
and verify the configuration is rejected with EINVAL.
Signed-off-by: Xiang Mei <xmei5@asu.edu> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Reviewed-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20260331050217.504278-3-xmei5@asu.edu Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Xiang Mei [Tue, 31 Mar 2026 05:02:16 +0000 (22:02 -0700)]
net/sched: cls_flow: fix NULL pointer dereference on shared blocks
flow_change() calls tcf_block_q() and dereferences q->handle to derive
a default baseclass. Shared blocks leave block->q NULL, causing a NULL
deref when a flow filter without a fully qualified baseclass is created
on a shared block.
Check tcf_block_shared() before accessing block->q and return -EINVAL
for shared blocks. This avoids the null-deref shown below:
=======================================================================
KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f]
RIP: 0010:flow_change (net/sched/cls_flow.c:508)
Call Trace:
tc_new_tfilter (net/sched/cls_api.c:2432)
rtnetlink_rcv_msg (net/core/rtnetlink.c:6980)
[...]
=======================================================================
Fixes: 1abf272022cf ("net: sched: tcindex, fw, flow: use tcf_block_q helper to get struct Qdisc") Reported-by: Weiming Shi <bestswngs@gmail.com> Signed-off-by: Xiang Mei <xmei5@asu.edu> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://patch.msgid.link/20260331050217.504278-2-xmei5@asu.edu Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Xiang Mei [Tue, 31 Mar 2026 05:02:15 +0000 (22:02 -0700)]
net/sched: cls_fw: fix NULL pointer dereference on shared blocks
The old-method path in fw_classify() calls tcf_block_q() and
dereferences q->handle. Shared blocks leave block->q NULL, causing a
NULL deref when an empty cls_fw filter is attached to a shared block
and a packet with a nonzero major skb mark is classified.
Reject the configuration in fw_change() when the old method (no
TCA_OPTIONS) is used on a shared block, since fw_classify()'s
old-method path needs block->q which is NULL for shared blocks.
The fixed null-ptr-deref calling stack:
KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f]
RIP: 0010:fw_classify (net/sched/cls_fw.c:81)
Call Trace:
tcf_classify (./include/net/tc_wrapper.h:197 net/sched/cls_api.c:1764 net/sched/cls_api.c:1860)
tc_run (net/core/dev.c:4401)
__dev_queue_xmit (net/core/dev.c:4535 net/core/dev.c:4790)
Fixes: 1abf272022cf ("net: sched: tcindex, fw, flow: use tcf_block_q helper to get struct Qdisc") Reported-by: Weiming Shi <bestswngs@gmail.com> Signed-off-by: Xiang Mei <xmei5@asu.edu> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://patch.msgid.link/20260331050217.504278-1-xmei5@asu.edu Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Martin Schiller [Tue, 31 Mar 2026 07:43:17 +0000 (09:43 +0200)]
net/x25: Fix potential double free of skb
When alloc_skb fails in x25_queue_rx_frame it calls kfree_skb(skb) at
line 48 and returns 1 (error).
This error propagates back through the call chain:
x25_queue_rx_frame returns 1
|
v
x25_state3_machine receives the return value 1 and takes the else
branch at line 278, setting queued=0 and returning 0
|
v
x25_process_rx_frame returns queued=0
|
v
x25_backlog_rcv at line 452 sees queued=0 and calls kfree_skb(skb)
again
This would free the same skb twice. Looking at x25_backlog_rcv:
Merge tag 'asoc-fix-v7.0-rc6' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Fixes for v7.0
Another smallish batch of fixes and quirks, these days it's AMD that is
getting all the DMI entries added. We've got one core fix for a missing
list initialisation with auxiliary devices, otherwise it's all fairly
small things.
Jakub Kicinski [Thu, 2 Apr 2026 03:13:00 +0000 (20:13 -0700)]
Merge branch 'bnxt_en-bug-fixes'
Michael Chan says:
====================
bnxt_en: Bug fixes
The first patch is a refactor patch needed by the second patch to
fix XDP ring initialization during FW reset. The third patch
fixes an issue related to stats context reservation for RoCE.
====================
Pavan Chebbi [Tue, 31 Mar 2026 06:51:38 +0000 (23:51 -0700)]
bnxt_en: Restore default stat ctxs for ULP when resource is available
During resource reservation, if the L2 driver does not have enough
MSIX vectors to provide to the RoCE driver, it sets the stat ctxs for
ULP also to 0 so that we don't have to reserve it unnecessarily.
However, subsequently the user may reduce L2 rings thereby freeing up
some resources that the L2 driver can now earmark for RoCE. In this
case, the driver should restore the default ULP stat ctxs to make
sure that all RoCE resources are ready for use.
The RoCE driver may fail to initialize in this scenario without this
fix.
Fixes: d630624ebd70 ("bnxt_en: Utilize ulp client resources if RoCE is not registered") Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com> Signed-off-by: Pavan Chebbi <pavan.chebbi@broadcom.com> Signed-off-by: Michael Chan <michael.chan@broadcom.com> Link: https://patch.msgid.link/20260331065138.948205-4-michael.chan@broadcom.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Michael Chan [Tue, 31 Mar 2026 06:51:37 +0000 (23:51 -0700)]
bnxt_en: Don't assume XDP is never enabled in bnxt_init_dflt_ring_mode()
The original code made the assumption that when we set up the initial
default ring mode, we must be just loading the driver and XDP cannot
be enabled yet. This is not true when the FW goes through a resource
or capability change. Resource reservations will be cancelled and
reinitialized with XDP already enabled. devlink reload with XDP enabled
will also have the same issue. This scenario will cause the ring
arithmetic to be all wrong in the bnxt_init_dflt_ring_mode() path
causing failure:
bnxt_en 0000:a1:00.0 ens2f0np0: bnxt_setup_int_mode err: ffffffea
bnxt_en 0000:a1:00.0 ens2f0np0: bnxt_request_irq err: ffffffea
bnxt_en 0000:a1:00.0 ens2f0np0: nic open fail (rc: ffffffea)
Fix it by properly accounting for XDP in the bnxt_init_dflt_ring_mode()
path by using the refactored helper functions in the previous patch.
Reviewed-by: Andy Gospodarek <andrew.gospodarek@broadcom.com> Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com> Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com> Fixes: ec5d31e3c15d ("bnxt_en: Handle firmware reset status during IF_UP.") Fixes: 228ea8c187d8 ("bnxt_en: implement devlink dev reload driver_reinit") Signed-off-by: Michael Chan <michael.chan@broadcom.com> Link: https://patch.msgid.link/20260331065138.948205-3-michael.chan@broadcom.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Michael Chan [Tue, 31 Mar 2026 06:51:36 +0000 (23:51 -0700)]
bnxt_en: Refactor some basic ring setup and adjustment logic
Refactor out the basic code that trims the default rings, sets up and
adjusts XDP TX rings and CP rings. There is no change in behavior.
This is to prepare for the next bug fix patch.
Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com> Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com> Reviewed-by: Andy Gospodarek <andrew.gospodarek@broadcom.com> Signed-off-by: Michael Chan <michael.chan@broadcom.com> Link: https://patch.msgid.link/20260331065138.948205-2-michael.chan@broadcom.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Saeed Mahameed [Mon, 30 Mar 2026 19:40:15 +0000 (22:40 +0300)]
net/mlx5: Fix switchdev mode rollback in case of failure
If for some internal reason switchdev mode fails, we rollback to legacy
mode, before this patch, rollback will unregister the uplink netdev and
leave it unregistered causing the below kernel bug.
To fix this, we need to avoid netdev unregister by setting the proper
rollback flag 'MLX5_PRIV_FLAGS_SWITCH_LEGACY' to indicate legacy mode.
Saeed Mahameed [Mon, 30 Mar 2026 19:40:14 +0000 (22:40 +0300)]
net/mlx5: Avoid "No data available" when FW version queries fail
Avoid printing the misleading "kernel answers: No data available" devlink
output when querying firmware or pending firmware version fails
(e.g. MLX5 fw state errors / flash failures).
FW can fail on loading the pending flash image and get its version due
to various reasons, examples:
mlxfw: Firmware flash failed: key not applicable, err (7)
mlx5_fw_image_pending: can't read pending fw version while fw state is 1
and the resulting:
$ devlink dev info
kernel answers: No data available
Instead, just report 0 or 0xfff.. versions in case of failure to indicate
a problem, and let other information be shown.
after the fix:
$ devlink dev info
pci/0000:00:06.0:
driver mlx5_core
serial_number xxx...
board.serial_number MT2225300179
versions:
fixed:
fw.psid MT_0000000436
running:
fw.version 22.41.0188
fw 22.41.0188
stored:
fw.version 255.255.65535
fw 255.255.65535
Shay Drory [Mon, 30 Mar 2026 19:40:13 +0000 (22:40 +0300)]
net/mlx5: lag: Check for LAG device before creating debugfs
__mlx5_lag_dev_add_mdev() may return 0 (success) even when an error
occurs that is handled gracefully. Consequently, the initialization
flow proceeds to call mlx5_ldev_add_debugfs() even when there is no
valid LAG context.
mlx5_ldev_add_debugfs() blindly created the debugfs directory and
attributes. This exposed interfaces (like the members file) that rely on
a valid ldev pointer, leading to potential NULL pointer dereferences if
accessed when ldev is NULL.
Add a check to verify that mlx5_lag_dev(dev) returns a valid pointer
before attempting to create the debugfs entries.
Fixes: 7f46a0b7327a ("net/mlx5: Lag, add debugfs to query hardware lag state") Signed-off-by: Shay Drory <shayd@nvidia.com> Reviewed-by: Mark Bloch <mbloch@nvidia.com> Signed-off-by: Tariq Toukan <tariqt@nvidia.com> Link: https://patch.msgid.link/20260330194015.53585-2-tariqt@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Fedor Pchelkin [Mon, 30 Mar 2026 18:45:40 +0000 (21:45 +0300)]
net: macb: fix clk handling on PCI glue driver removal
platform_device_unregister() may still want to use the registered clks
during runtime resume callback.
Note that there is a commit d82d5303c4c5 ("net: macb: fix use after free
on rmmod") that addressed the similar problem of clk vs platform device
unregistration but just moved the bug to another place.
Save the pointers to clks into local variables for reuse after platform
device is unregistered.
BUG: KASAN: use-after-free in clk_prepare+0x5a/0x60
Read of size 8 at addr ffff888104f85e00 by task modprobe/597
Srujana Challa [Thu, 26 Mar 2026 14:23:44 +0000 (19:53 +0530)]
virtio_net: clamp rss_max_key_size to NETDEV_RSS_KEY_LEN
rss_max_key_size in the virtio spec is the maximum key size supported by
the device, not a mandatory size the driver must use. Also the value 40
is a spec minimum, not a spec maximum.
The current code rejects RSS and can fail probe when the device reports a
larger rss_max_key_size than the driver buffer limit. Instead, clamp the
effective key length to min(device rss_max_key_size, NETDEV_RSS_KEY_LEN)
and keep RSS enabled.
This keeps probe working on devices that advertise larger maximum key sizes
while respecting the netdev RSS key buffer size limit.
Fixes: 3f7d9c1964fc ("virtio_net: Add hash_key_length check") Cc: stable@vger.kernel.org Signed-off-by: Srujana Challa <schalla@marvell.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Link: https://patch.msgid.link/20260326142344.1171317-1-schalla@marvell.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Yucheng Lu [Tue, 31 Mar 2026 08:00:21 +0000 (16:00 +0800)]
net/sched: sch_netem: fix out-of-bounds access in packet corruption
In netem_enqueue(), the packet corruption logic uses
get_random_u32_below(skb_headlen(skb)) to select an index for
modifying skb->data. When an AF_PACKET TX_RING sends fully non-linear
packets over an IPIP tunnel, skb_headlen(skb) evaluates to 0.
Passing 0 to get_random_u32_below() takes the variable-ceil slow path
which returns an unconstrained 32-bit random integer. Using this
unconstrained value as an offset into skb->data results in an
out-of-bounds memory access.
Fix this by verifying skb_headlen(skb) is non-zero before attempting
to corrupt the linear data area. Fully non-linear packets will silently
bypass the corruption logic.
Fixes: c865e5d99e25 ("[PKT_SCHED] netem: packet corruption option") Reported-by: Yifan Wu <yifanwucs@gmail.com> Reported-by: Juefei Pu <tomapufckgml@gmail.com> Signed-off-by: Yuan Tan <tanyuan98@outlook.com> Signed-off-by: Xin Liu <bird@lzu.edu.cn> Signed-off-by: Yuhang Zheng <z1652074432@gmail.com> Signed-off-by: Yucheng Lu <kanolyc@gmail.com> Reviewed-by: Stephen Hemminger <stephen@networkplumber.org> Link: https://patch.msgid.link/45435c0935df877853a81e6d06205ac738ec65fa.1774941614.git.kanolyc@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Jakub Kicinski [Thu, 2 Apr 2026 02:19:35 +0000 (19:19 -0700)]
Merge tag 'nf-26-04-01' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains Netfilter fixes for net. Note that most
of the bugs fixed here are >5 years old. The large PR is not due to an
increase in regressions.
1) Flowtable hardware offload support in IPv6 can lead to out-of-bounds
when populating the rule action array when combined with double-tagged
vlan. Bump the maximum number of actions from 16 to 24 and check that
such limit is never reached, otherwise bail out. This bugs stems from
the original flowtable hardware offload support.
2) nfnetlink_log does not include the netlink header size of the trailing
NLMSG_DONE message when calculating the skb size. From Florian Westphal.
3) Reject names in xt_cgroup and xt_rateest extensions which are not
nul-terminated. Also from Florian.
4) Use nla_strcmp in ipset lookup by set name, since IPSET_ATTR_NAME and
IPSET_ATTR_NAMEREF are of NLA_STRING type. From Florian Westphal.
5) When unregistering conntrack helpers, pass the helper that is going
away so the expectation cleanup is done accordingly, otherwise UaF is
possible when accessing expectation that refer to the helper that is
gone. From Qi Tang.
6) Zero expectation NAT fields to address leaking kernel memory through
the expectation netlink dump when unset. Also from Qi Tang.
7) Use the master conntrack helper when creating expectations via
ctnetlink, ignore the suggested helper through CTA_EXPECT_HELP_NAME.
This allows to address a possible read of kernel memory off the
expectation object boundary.
8) Fix incorrect release of the hash bucket logic in ipset when the
bucket is empty, leading to shrinking the hash bucket to size 0
which deals to out-of-bound write in next element additions.
From Yifan Wu.
9) Allow the use of x_tables extensions that explicitly declare
NFPROTO_ARP support only. This is to avoid an incorrect hook number
validation due to non-overlapping arp and inet hook number
definitions.
10) Reject immediate NF_QUEUE verdict in nf_tables. The userspace
nft tool always uses the nft_queue expression for queueing.
This ensures this verdict cannot be used for the arp family,
which does supported this.
* tag 'nf-26-04-01' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
netfilter: nf_tables: reject immediate NF_QUEUE verdict
netfilter: x_tables: restrict xt_check_match/xt_check_target extensions for NFPROTO_ARP
netfilter: ipset: drop logically empty buckets in mtype_del
netfilter: ctnetlink: ignore explicit helper on new expectations
netfilter: ctnetlink: zero expect NAT fields when CTA_EXPECT_NAT absent
netfilter: nf_conntrack_helper: pass helper to expect cleanup
netfilter: ipset: use nla_strcmp for IPSET_ATTR_NAME attr
netfilter: x_tables: ensure names are nul-terminated
netfilter: nfnetlink_log: account for netlink header size
netfilter: flowtable: strictly check for maximum number of actions
====================
bpf: sockmap: Fix use-after-free of sk->sk_socket in sk_psock_verdict_data_ready().
syzbot reported use-after-free of AF_UNIX socket's sk->sk_socket
in sk_psock_verdict_data_ready(). [0]
In unix_stream_sendmsg(), the peer socket's ->sk_data_ready() is
called after dropping its unix_state_lock().
Although the sender socket holds the peer's refcount, it does not
prevent the peer's sock_orphan(), and the peer's sk_socket might
be freed after one RCU grace period.
Let's fetch the peer's sk->sk_socket and sk->sk_socket->ops under
RCU in sk_psock_verdict_data_ready().
[0]:
BUG: KASAN: slab-use-after-free in sk_psock_verdict_data_ready+0xec/0x590 net/core/skmsg.c:1278
Read of size 8 at addr ffff8880594da860 by task syz.4.1842/11013
Weiming Shi [Mon, 30 Mar 2026 16:32:38 +0000 (00:32 +0800)]
rds: ib: reject FRMR registration before IB connection is established
rds_ib_get_mr() extracts the rds_ib_connection from conn->c_transport_data
and passes it to rds_ib_reg_frmr() for FRWR memory registration. On a
fresh outgoing connection, ic is allocated in rds_ib_conn_alloc() with
i_cm_id = NULL because the connection worker has not yet called
rds_ib_conn_path_connect() to create the rdma_cm_id. When sendmsg() with
RDS_CMSG_RDMA_MAP is called on such a connection, the sendmsg path parses
the control message before any connection establishment, allowing
rds_ib_post_reg_frmr() to dereference ic->i_cm_id->qp and crash the
kernel.
The existing guard in rds_ib_reg_frmr() only checks for !ic (added in
commit 9e630bcb7701), which does not catch this case since ic is allocated
early and is always non-NULL once the connection object exists.
Add a check in rds_ib_get_mr() that verifies ic, i_cm_id, and qp are all
non-NULL before proceeding with FRMR registration, mirroring the guard
already present in rds_ib_post_inv(). Return -ENODEV when the connection
is not ready, which the existing error handling in rds_cmsg_send() converts
to -EAGAIN for userspace retry and triggers rds_conn_connect_if_down() to
start the connection worker.
Fixes: 1659185fb4d0 ("RDS: IB: Support Fastreg MR (FRMR) memory registration mode") Reported-by: Xiang Mei <xmei5@asu.edu> Signed-off-by: Weiming Shi <bestswngs@gmail.com> Reviewed-by: Allison Henderson <achender@kernel.org> Link: https://patch.msgid.link/20260330163237.2752440-2-bestswngs@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When two CPUs process Router Advertisement packets for the same router
simultaneously, they can both arrive at fib6_metric_set() with the same
fib6_info pointer whose fib6_metrics still points to dst_default_metrics.
Fix this by:
- Set val for p->metrics before published via cmpxchg() so the metrics
value is ready before the pointer becomes visible to other CPUs.
- Replace the plain pointer store with cmpxchg() and free the allocation
safely when competition failed.
- Add READ_ONCE()/WRITE_ONCE() for metrics[] setting in the non-default
metrics path to prevent compiler-based data races.
Fixes: d4ead6b34b67 ("net/ipv6: move metrics from dst to rt6_info") Reported-by: Fei Liu <feliu@redhat.com> Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260331-b4-fib6_metric_set-kmemleak-v3-1-88d27f4d8825@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
hkbinbin [Tue, 31 Mar 2026 05:39:16 +0000 (05:39 +0000)]
Bluetooth: hci_sync: fix stack buffer overflow in hci_le_big_create_sync
hci_le_big_create_sync() uses DEFINE_FLEX to allocate a
struct hci_cp_le_big_create_sync on the stack with room for 0x11 (17)
BIS entries. However, conn->num_bis can hold up to HCI_MAX_ISO_BIS (31)
entries — validated against ISO_MAX_NUM_BIS (0x1f) in the caller
hci_conn_big_create_sync(). When conn->num_bis is between 18 and 31,
the memcpy that copies conn->bis into cp->bis writes up to 14 bytes
past the stack buffer, corrupting adjacent stack memory.
This is trivially reproducible: binding an ISO socket with
bc_num_bis = ISO_MAX_NUM_BIS (31) and calling listen() will
eventually trigger hci_le_big_create_sync() from the HCI command
sync worker, causing a KASAN-detectable stack-out-of-bounds write:
BUG: KASAN: stack-out-of-bounds in hci_le_big_create_sync+0x256/0x3b0
Write of size 31 at addr ffffc90000487b48 by task kworker/u9:0/71
Fix this by changing the DEFINE_FLEX count from the incorrect 0x11 to
HCI_MAX_ISO_BIS, which matches the maximum number of BIS entries that
conn->bis can actually carry.
Fixes: 42ecf1947135 ("Bluetooth: ISO: Do not emit LE BIG Create Sync if previous is pending") Cc: stable@vger.kernel.org Signed-off-by: hkbinbin <hkbinbinbin@gmail.com> Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Oleh Konko [Tue, 31 Mar 2026 11:52:13 +0000 (11:52 +0000)]
Bluetooth: SMP: derive legacy responder STK authentication from MITM state
The legacy responder path in smp_random() currently labels the stored
STK as authenticated whenever pending_sec_level is BT_SECURITY_HIGH.
That reflects what the local service requested, not what the pairing
flow actually achieved.
For Just Works/Confirm legacy pairing, SMP_FLAG_MITM_AUTH stays clear
and the resulting STK should remain unauthenticated even if the local
side requested HIGH security. Use the established MITM state when
storing the responder STK so the key metadata matches the pairing result.
This also keeps the legacy path aligned with the Secure Connections code,
which already treats JUST_WORKS/JUST_CFM as unauthenticated.
Fixes: fff3490f4781 ("Bluetooth: Fix setting correct authentication information for SMP STK") Cc: stable@vger.kernel.org Signed-off-by: Oleh Konko <security@1seal.org> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Oleh Konko [Tue, 31 Mar 2026 11:52:12 +0000 (11:52 +0000)]
Bluetooth: SMP: force responder MITM requirements before building the pairing response
smp_cmd_pairing_req() currently builds the pairing response from the
initiator auth_req before enforcing the local BT_SECURITY_HIGH
requirement. If the initiator omits SMP_AUTH_MITM, the response can
also omit it even though the local side still requires MITM.
tk_request() then sees an auth value without SMP_AUTH_MITM and may
select JUST_CFM, making method selection inconsistent with the pairing
policy the responder already enforces.
When the local side requires HIGH security, first verify that MITM can
be achieved from the IO capabilities and then force SMP_AUTH_MITM in the
response in both rsp.auth_req and auth. This keeps the responder auth bits
and later method selection aligned.
Fixes: 2b64d153a0cc ("Bluetooth: Add MITM mechanism to LE-SMP") Cc: stable@vger.kernel.org Suggested-by: Luiz Augusto von Dentz <luiz.dentz@gmail.com> Signed-off-by: Oleh Konko <security@1seal.org> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
mesh_send() currently bounds MGMT_OP_MESH_SEND by total command
length, but it never verifies that the bytes supplied for the
flexible adv_data[] array actually match the embedded adv_data_len
field. MGMT_MESH_SEND_SIZE only covers the fixed header, so a
truncated command can still pass the existing 20..50 byte range
check and later drive the async mesh send path past the end of the
queued command buffer.
Keep rejecting zero-length and oversized advertising payloads, but
validate adv_data_len explicitly and require the command length to
exactly match the flexible array size before queueing the request.
Fixes: b338d91703fa ("Bluetooth: Implement support for Mesh") Reported-by: Keenan Dong <keenanat2000@gmail.com> Signed-off-by: Keenan Dong <keenanat2000@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Pauli Virtanen [Sun, 29 Mar 2026 13:43:02 +0000 (16:43 +0300)]
Bluetooth: hci_event: fix potential UAF in hci_le_remote_conn_param_req_evt
hci_conn lookup and field access must be covered by hdev lock in
hci_le_remote_conn_param_req_evt, otherwise it's possible it is freed
concurrently.
Extend the hci_dev_lock critical section to cover all conn usage.
Fixes: 95118dd4edfec ("Bluetooth: hci_event: Use of a function table to handle LE subevents") Signed-off-by: Pauli Virtanen <pav@iki.fi> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Pauli Virtanen [Sun, 29 Mar 2026 13:43:01 +0000 (16:43 +0300)]
Bluetooth: hci_conn: fix potential UAF in set_cig_params_sync
hci_conn lookup and field access must be covered by hdev lock in
set_cig_params_sync, otherwise it's possible it is freed concurrently.
Take hdev lock to prevent hci_conn from being deleted or modified
concurrently. Just RCU lock is not suitable here, as we also want to
avoid "tearing" in the configuration.
Fixes: a091289218202 ("Bluetooth: hci_conn: Fix hci_le_set_cig_params") Signed-off-by: Pauli Virtanen <pav@iki.fi> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Keenan Dong [Sat, 28 Mar 2026 08:46:47 +0000 (16:46 +0800)]
Bluetooth: MGMT: validate LTK enc_size on load
Load Long Term Keys stores the user-provided enc_size and later uses
it to size fixed-size stack operations when replying to LE LTK
requests. An enc_size larger than the 16-byte key buffer can therefore
overflow the reply stack buffer.
Reject oversized enc_size values while validating the management LTK
record so invalid keys never reach the stored key state.
Fixes: 346af67b8d11 ("Bluetooth: Add MGMT handlers for dealing with SMP LTK's") Reported-by: Keenan Dong <keenanat2000@gmail.com> Signed-off-by: Keenan Dong <keenanat2000@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Commit 5df5dafc171b ("Bluetooth: hci_uart: Fix another race during
initialization") fixed a race for hci commands sent during initialization.
However, there is still a race that happens if an hci event from one of
these commands is received before HCI_UART_REGISTERED has been set at
the end of hci_uart_register_dev(). The event will be ignored which
causes the command to fail with a timeout in the log:
"Bluetooth: hci0: command 0x1003 tx timeout"
This is because the hci event receive path (hci_uart_tty_receive ->
h4_recv) requires HCI_UART_REGISTERED to be set in h4_recv(), while the
hci command transmit path (hci_uart_send_frame -> h4_enqueue) only
requires HCI_UART_PROTO_INIT to be set in hci_uart_send_frame().
The check for HCI_UART_REGISTERED was originally added in commit c2578202919a ("Bluetooth: Fix H4 crash from incoming UART packets")
to fix a crash caused by hu->hdev being null dereferenced. That can no
longer happen: once HCI_UART_PROTO_INIT is set in hci_uart_register_dev()
all pointers (hu, hu->priv and hu->hdev) are valid, and
hci_uart_tty_receive() already calls h4_recv() on HCI_UART_PROTO_INIT
or HCI_UART_PROTO_READY.
Remove the check for HCI_UART_REGISTERED in h4_recv() to fix the race
condition.
Fixes: 5df5dafc171b ("Bluetooth: hci_uart: Fix another race during initialization") Signed-off-by: Jonathan Rissanen <jonathan.rissanen@axis.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Bluetooth: hci_sync: Fix UAF in le_read_features_complete
This fixes the following backtrace caused by hci_conn being freed
before le_read_features_complete but after
hci_le_read_remote_features_sync so hci_conn_del -> hci_cmd_sync_dequeue
is not able to prevent it:
==================================================================
BUG: KASAN: slab-use-after-free in instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
BUG: KASAN: slab-use-after-free in atomic_dec_and_test include/linux/atomic/atomic-instrumented.h:1383 [inline]
BUG: KASAN: slab-use-after-free in hci_conn_drop include/net/bluetooth/hci_core.h:1688 [inline]
BUG: KASAN: slab-use-after-free in le_read_features_complete+0x5b/0x340 net/bluetooth/hci_sync.c:7344
Write of size 4 at addr ffff8880796b0010 by task kworker/u9:0/52
The buggy address belongs to the object at ffff8880796b0000
which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 16 bytes inside of
freed 8192-byte region [ffff8880796b0000, ffff8880796b2000)
Memory state around the buggy address: ffff8880796aff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880796aff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880796b0000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^ ffff8880796b0080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880796b0100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
Fixes: a106e50be74b ("Bluetooth: HCI: Add support for LL Extended Feature Set") Reported-by: syzbot+87badbb9094e008e0685@syzkaller.appspotmail.com Tested-by: syzbot+87badbb9094e008e0685@syzkaller.appspotmail.com Closes: https://syzbot.org/bug?extid=87badbb9094e008e0685 Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Pauli Virtanen <pav@iki.fi>
Pauli Virtanen [Wed, 25 Mar 2026 19:07:43 +0000 (21:07 +0200)]
Bluetooth: hci_sync: hci_cmd_sync_queue_once() return -EEXIST if exists
hci_cmd_sync_queue_once() needs to indicate whether a queue item was
added, so caller can know if callbacks are called, so it can avoid
leaking resources.
Change the function to return -EEXIST if queue item already exists.
Modify all callsites to handle that.
Signed-off-by: Pauli Virtanen <pav@iki.fi> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Oleh Konko [Thu, 26 Mar 2026 17:31:24 +0000 (17:31 +0000)]
Bluetooth: hci_event: move wake reason storage into validated event handlers
hci_store_wake_reason() is called from hci_event_packet() immediately
after stripping the HCI event header but before hci_event_func()
enforces the per-event minimum payload length from hci_ev_table.
This means a short HCI event frame can reach bacpy() before any bounds
check runs.
Rather than duplicating skb parsing and per-event length checks inside
hci_store_wake_reason(), move wake-address storage into the individual
event handlers after their existing event-length validation has
succeeded. Convert hci_store_wake_reason() into a small helper that only
stores an already-validated bdaddr while the caller holds hci_dev_lock().
Use the same helper after hci_event_func() with a NULL address to
preserve the existing unexpected-wake fallback semantics when no
validated event handler records a wake address.
Annotate the helper with __must_hold(&hdev->lock) and add
lockdep_assert_held(&hdev->lock) so future call paths keep the lock
contract explicit.
Call the helper from hci_conn_request_evt(), hci_conn_complete_evt(),
hci_sync_conn_complete_evt(), le_conn_complete_evt(),
hci_le_adv_report_evt(), hci_le_ext_adv_report_evt(),
hci_le_direct_adv_report_evt(), hci_le_pa_sync_established_evt(), and
hci_le_past_received_evt().
Fixes: 2f20216c1d6f ("Bluetooth: Emit controller suspend and resume events") Cc: stable@vger.kernel.org Signed-off-by: Oleh Konko <security@1seal.org> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Cen Zhang [Thu, 26 Mar 2026 15:16:45 +0000 (23:16 +0800)]
Bluetooth: SCO: fix race conditions in sco_sock_connect()
sco_sock_connect() checks sk_state and sk_type without holding
the socket lock. Two concurrent connect() syscalls on the same
socket can both pass the check and enter sco_connect(), leading
to use-after-free.
The buggy scenario involves three participants and was confirmed
with additional logging instrumentation:
Thread A (connect): HCI disconnect: Thread B (connect):
Thread B revives a BT_CLOSED + SOCK_ZAPPED socket back to
BT_CONNECT. Subsequent cleanup triggers double sock_put() and
use-after-free. Meanwhile conn1 is leaked as it was orphaned
when sco_conn_del() cleared the association.
Fix this by:
- Moving lock_sock() before the sk_state/sk_type checks in
sco_sock_connect() to serialize concurrent connect attempts
- Fixing the sk_type != SOCK_SEQPACKET check to actually
return the error instead of just assigning it
- Adding a state re-check in sco_connect() after lock_sock()
to catch state changes during the window between the locks
- Adding sco_pi(sk)->conn check in sco_chan_add() to prevent
double-attach of a socket to multiple connections
- Adding hci_conn_drop() on sco_chan_add failure to prevent
HCI connection leaks
Fixes: 9a8ec9e8ebb5 ("Bluetooth: SCO: Fix possible circular locking dependency on sco_connect_cfm") Signed-off-by: Cen Zhang <zzzccc427@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Pauli Virtanen [Wed, 25 Mar 2026 19:07:46 +0000 (21:07 +0200)]
Bluetooth: hci_sync: call destroy in hci_cmd_sync_run if immediate
hci_cmd_sync_run() may run the work immediately if called from existing
sync work (otherwise it queues a new sync work). In this case it fails
to call the destroy() function.
On immediate run, make it behave same way as if item was queued
successfully: call destroy, and return 0.
The only callsite is hci_abort_conn() via hci_cmd_sync_run_once(), and
this changes its return value. However, its return value is not used
except as the return value for hci_disconnect(), and nothing uses the
return value of hci_disconnect(). Hence there should be no behavior
change anywhere.
Fixes: c898f6d7b093b ("Bluetooth: hci_sync: Introduce hci_cmd_sync_run/hci_cmd_sync_run_once") Signed-off-by: Pauli Virtanen <pav@iki.fi> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Simon Trimmer [Tue, 31 Mar 2026 13:19:16 +0000 (13:19 +0000)]
ASoC: amd: ps: Fix missing leading zeros in subsystem_device SSID log
Ensure that subsystem_device is printed with leading zeros when combined
with subsystem_vendor to form the SSID. Without this, devices with upper
bits unset may appear to have an incorrect SSID in the debug output.
nft_queue is always used from userspace nftables to deliver the NF_QUEUE
verdict. Immediately emitting an NF_QUEUE verdict is never used by the
userspace nft tools, so reject immediate NF_QUEUE verdicts.
The arp family does not provide queue support, but such an immediate
verdict is still reachable. Globally reject NF_QUEUE immediate verdicts
to address this issue.
netfilter: x_tables: restrict xt_check_match/xt_check_target extensions for NFPROTO_ARP
Weiming Shi says:
xt_match and xt_target structs registered with NFPROTO_UNSPEC can be
loaded by any protocol family through nft_compat. When such a
match/target sets .hooks to restrict which hooks it may run on, the
bitmask uses NF_INET_* constants. This is only correct for families
whose hook layout matches NF_INET_*: IPv4, IPv6, INET, and bridge
all share the same five hooks (PRE_ROUTING ... POST_ROUTING).
ARP only has three hooks (IN=0, OUT=1, FORWARD=2) with different
semantics. Because NF_ARP_OUT == 1 == NF_INET_LOCAL_IN, the .hooks
validation silently passes for the wrong reasons, allowing matches to
run on ARP chains where the hook assumptions (e.g. state->in being
set on input hooks) do not hold. This leads to NULL pointer
dereferences; xt_devgroup is one concrete example:
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000044: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000220-0x0000000000000227]
RIP: 0010:devgroup_mt+0xff/0x350
Call Trace:
<TASK>
nft_match_eval (net/netfilter/nft_compat.c:407)
nft_do_chain (net/netfilter/nf_tables_core.c:285)
nft_do_chain_arp (net/netfilter/nft_chain_filter.c:61)
nf_hook_slow (net/netfilter/core.c:623)
arp_xmit (net/ipv4/arp.c:666)
</TASK>
Kernel panic - not syncing: Fatal exception in interrupt
Fix it by restricting arptables to NFPROTO_ARP extensions only.
Note that arptables-legacy only supports:
- arpt_CLASSIFY
- arpt_mangle
- arpt_MARK
that provide explicit NFPROTO_ARP match/target declarations.
Fixes: 9291747f118d ("netfilter: xtables: add device group match") Reported-by: Xiang Mei <xmei5@asu.edu> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Yifan Wu [Mon, 30 Mar 2026 21:39:24 +0000 (14:39 -0700)]
netfilter: ipset: drop logically empty buckets in mtype_del
mtype_del() counts empty slots below n->pos in k, but it only drops the
bucket when both n->pos and k are zero. This misses buckets whose live
entries have all been removed while n->pos still points past deleted slots.
Treat a bucket as empty when all positions below n->pos are unused and
release it directly instead of shrinking it further.
Fixes: 8af1c6fbd923 ("netfilter: ipset: Fix forceadd evaluation path") Cc: stable@vger.kernel.org Reported-by: Juefei Pu <tomapufckgml@gmail.com> Reported-by: Xin Liu <dstsmallbird@foxmail.com> Signed-off-by: Yifan Wu <yifanwucs@gmail.com> Co-developed-by: Yuan Tan <yuantan098@gmail.com> Signed-off-by: Yuan Tan <yuantan098@gmail.com> Reviewed-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
netfilter: ctnetlink: ignore explicit helper on new expectations
Use the existing master conntrack helper, anything else is not really
supported and it just makes validation more complicated, so just ignore
what helper userspace suggests for this expectation.
This was uncovered when validating CTA_EXPECT_CLASS via different helper
provided by userspace than the existing master conntrack helper:
BUG: KASAN: slab-out-of-bounds in nf_ct_expect_related_report+0x2479/0x27c0
Read of size 4 at addr ffff8880043fe408 by task poc/102
Call Trace:
nf_ct_expect_related_report+0x2479/0x27c0
ctnetlink_create_expect+0x22b/0x3b0
ctnetlink_new_expect+0x4bd/0x5c0
nfnetlink_rcv_msg+0x67a/0x950
netlink_rcv_skb+0x120/0x350
Allowing to read kernel memory bytes off the expectation boundary.
CTA_EXPECT_HELP_NAME is still used to offer the helper name to userspace
via netlink dump.
Fixes: bd0779370588 ("netfilter: nfnetlink_queue: allow to attach expectations to conntracks") Reported-by: Qi Tang <tpluszz77@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
projects / thirdparty / kernel / linux.git / log
