When compiling BPF selftests with -O2, GCC reports a maybe-uninitialized
warning in libarena code:
In file included from /bpf-next/tools/testing/selftests/bpf/prog_tests/libarena_asan.c:11:
In function ‘libarena_asan_init’,
inlined from ‘run_test’ at /bpf-next/tools/testing/selftests/bpf/prog_tests/libarena_asan.c:59:8,
inlined from ‘test_libarena_asan’ at /bpf-next/tools/testing/selftests/bpf/prog_tests/libarena_asan.c:91:2:
/bpf-next/tools/testing/selftests/bpf/libarena/include/libarena/userspace.h:126:14: error: ‘globals_pages’ may be used uninitialized [-Werror=maybe-uninitialized]
126 | args = (struct asan_init_args){
| ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
127 | .arena_all_pages = arena_all_pages,
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
128 | .arena_globals_pages = globals_pages,
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
129 | };
| ~
/bpf-next/tools/testing/selftests/bpf/libarena/include/libarena/userspace.h: In function ‘test_libarena_asan’:
/bpf-next/tools/testing/selftests/bpf/libarena/include/libarena/userspace.h:118:13: note: ‘globals_pages’ was declared here
118 | u64 globals_pages;
| ^~~~~~~~~~~~~
Silence the warning by initializing globals_pages to 0.
Fixes: cfc00618b9 ("selftests/bpf: Add ASAN support for libarena selftests")
Signed-off-by: Viktor Malik <vmalik@redhat.com>
Link: https://lore.kernel.org/bpf/9f77a5c05c3c731ab2655fd66716ab9de4478b15.1784112948.git.vmalik@redhat.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
When compiling BPF selftests with -O2, GCC reports an array bounds
violation warning in global_map_resize test:
In function ‘global_map_resize_bss_subtest’,
inlined from ‘test_global_map_resize’ at /bpf-next/tools/testing/selftests/bpf/prog_tests/global_map_resize.c:228:3:
/bpf-next/tools/testing/selftests/bpf/prog_tests/global_map_resize.c:64:33: error: array subscript 1 is above array bounds of ‘int[1]’ [-Werror=array-bounds=]
64 | skel->bss->array[i] = 1;
| ~~~~~~~~~~~~~~~~^~~
In file included from /bpf-next/tools/testing/selftests/bpf/prog_tests/global_map_resize.c:6:
./test_global_map_resize.skel.h: In function ‘test_global_map_resize’:
./test_global_map_resize.skel.h:44:21: note: while referencing ‘array’
44 | int array[1];
| ^~~~~
This is a false positive because `array` (a BPF map) has been resized
from within the BPF program. GCC doesn't know that so let us silence the
warning by accessing the array via a plain pointer.
Fixes: 08b0895675 ("libbpf: Selftests for resizing datasec maps")
Signed-off-by: Viktor Malik <vmalik@redhat.com>
Link: https://lore.kernel.org/bpf/57765bc465a27923c3c093eba222cc24d08d8c40.1784112948.git.vmalik@redhat.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Replace ASSERT_OK_PTR by ASSERT_NEQ(res, NULL, ...) when checking the
result of malloc. It is more accurate since malloc returns NULL, not an
error code, on failure and it also prevents the following false GCC
warning when compiling BPF selftests with -O2:
In file included from /bpf-next/tools/testing/selftests/bpf/prog_tests/sha256.c:4:
/bpf-next/tools/testing/selftests/bpf/prog_tests/sha256.c: In function ‘test_sha256’:
./test_progs.h:393:22: error: ‘data’ may be used uninitialized [-Werror=maybe-uninitialized]
393 | int ___err = libbpf_get_error(___res); \
| ^~~~~~~~~~~~~~~~~~~~~~~~
/bpf-next/tools/testing/selftests/bpf/prog_tests/sha256.c:28:14: note: in expansion of macro ‘ASSERT_OK_PTR’
28 | if (!ASSERT_OK_PTR(data, "malloc"))
| ^~~~~~~~~~~~~
In file included from /bpf-next/tools/testing/selftests/bpf/tools/include/bpf/bpf.h:32,
from ./test_progs.h:37:
/bpf-next/tools/testing/selftests/bpf/tools/include/bpf/libbpf_legacy.h:113:17: note: by argument 1 of type ‘const void *’ to ‘libbpf_get_error’ declared here
113 | LIBBPF_API long libbpf_get_error(const void *ptr);
| ^~~~~~~~~~~~~~~~
Fixes: f09f57c746 ("selftests/bpf: Add test for libbpf_sha256()")
Signed-off-by: Viktor Malik <vmalik@redhat.com>
Link: https://lore.kernel.org/bpf/f9dec09cca0c2aa5eeb4fdcd400a13aa19e2c073.1784112948.git.vmalik@redhat.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Replace ASSERT_OK_PTR by ASSERT_NEQ(res, NULL, ...) when checking the
result of malloc. It is more accurate since malloc returns NULL, not an
error code, on failure and it also prevents the following false GCC
warning when compiling BPF selftests with -O2:
In file included from test_loader.c:6:
test_loader.c: In function ‘verify_stderr’:
/bpf-next/tools/testing/selftests/bpf/test_progs.h:393:22: error: ‘buf’ may be used uninitialized [-Werror=maybe-uninitialized]
393 | int ___err = libbpf_get_error(___res); \
| ^~~~~~~~~~~~~~~~~~~~~~~~
test_loader.c:810:14: note: in expansion of macro ‘ASSERT_OK_PTR’
810 | if (!ASSERT_OK_PTR(buf, "malloc"))
| ^~~~~~~~~~~~~
In file included from /bpf-next/tools/testing/selftests/bpf/tools/include/bpf/bpf.h:32,
from /bpf-next/tools/testing/selftests/bpf/test_progs.h:37:
/bpf-next/tools/testing/selftests/bpf/tools/include/bpf/libbpf_legacy.h:113:17: note: by argument 1 of type ‘const void *’ to ‘libbpf_get_error’ declared here
113 | LIBBPF_API long libbpf_get_error(const void *ptr);
| ^~~~~~~~~~~~~~~~
Fixes: 554e4eb9e4 ("selftests/bpf: Reuse stderr parsing for libarena ASAN tests")
Signed-off-by: Viktor Malik <vmalik@redhat.com>
Link: https://lore.kernel.org/bpf/e25d50805fbcb3632f24b488568ab5ba49b82094.1784112948.git.vmalik@redhat.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Looking up a prog or map by name walks the whole id space. There is a
window between bpf_prog_get_next_id()/bpf_map_get_next_id() and getting
an fd for that id in which an unrelated object can be freed, and the
lookup then fails with ENOENT and aborts the whole command.
Skip such ids and keep walking, the same way do_show() already does.
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Link: https://lore.kernel.org/bpf/20260720071520.396363-1-jiayuan.chen@linux.dev
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Leon Hwang says:
====================
bpf: Disallow interpreter fallback for interpreter-unsupported insns
Sashiko reported two potential issues about interpreter fallback [1]
[2].
After verifying them by patch #7 of v1, I think they are real issues. With
LLM assistance, the interpreter does not support the internal
BPF_PROBE_ATOMIC insn and the gotox insn (used for indirect jumps),
either.
1) the user BPF_ADDR_SPACE_CAST insn
the interpreter just ignores it.
2) the arena ST/STX/LDX insn
the interpreter could hit the BUG_ON() in ___bpf_prog_run().
3) the BPF_MOV64_PERCPU_REG insn
the interpreter could hit page fault, due to loading memory from
invalid __percpu pointer.
4) the internal BPF_PROBE_ATOMIC insn
the interpreter could hit the BUG_ON() in ___bpf_prog_run().
5) the gotox insn used for indirect jumps
the interpreter could hit the BUG_ON() in ___bpf_prog_run(), too.
Reject these insns on interpreter fallback path in
__bpf_prog_select_runtime() by setting 'jit_required = true'.
Link:
[1] https://lore.kernel.org/bpf/20260608151347.2C77D1F00893@smtp.kernel.org/
[2] https://lore.kernel.org/bpf/20260622150759.EC9071F000E9@smtp.kernel.org/
Changes:
v1 -> v2:
* Drop RFC.
* Change target tree to bpf-next to utilize the 'jit_required' bit.
* Set jit_required as true if there's arena map, then all arena-related
insns will be rejected if JIT is not available.
* Set jit_required as true if there's insn_array map, then the gotox
insns will be rejected if JIT is not available.
* Drop the issues-proven patch.
* v1: https://lore.kernel.org/bpf/20260626154330.33619-1-leon.hwang@linux.dev/
====================
Link: https://patch.msgid.link/20260715141122.15783-1-leon.hwang@linux.dev
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
The BPF_MOV64_PERCPU_REG insn requires JIT to emit native code to for
'dst_reg = src_reg + <percpu_base_off>'.
However, the interpreter ignores the 'off' at its ALU64_MOV_X label.
The 'off' indicates the insn is BPF_MOV64_PERCPU_REG insn. Then, when
the interpreter loads memory from the register, it will hit a page
fault.
[ 2.545572] BUG: unable to handle page fault for address: ffffffffacaaf034
[ 2.546485] #PF: supervisor read access in kernel mode
[ 2.547167] #PF: error_code(0x0000) - not-present page
[ 2.547850] PGD 134e63067 P4D 134e63067 PUD 134e64063 PMD 10021c063 PTE 800ffffeca550062
[ 2.548912] Oops: Oops: 0000 [#1] SMP PTI
Set jit_required as true in order to disallow interpreter fallback in
core.c::__bpf_prog_select_runtime(), if any BPF_ADDR_PERCPU insn is
patched to the prog.
BTW, rename the helper bpf_map_supports_cpu_flags() to
bpf_map_is_percpu_map().
Fixes: 7bdbf74463 ("bpf: add special internal-only MOV instruction to resolve per-CPU addrs")
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Link: https://lore.kernel.org/bpf/20260715141122.15783-4-leon.hwang@linux.dev
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
The interpreter does not recognize the BPF_JMP|BPF_JA|BPF_X insn, which
is used for insn_array map. Thereafter, it would hit the BUG_ON() in
___bpf_prog_run() at run time.
[ 2.563726] BPF interpreter: unknown opcode 0d (imm: 0x0)
[ 2.564557] ------------[ cut here ]------------
[ 2.565206] kernel BUG at kernel/bpf/core.c:2349!
[ 2.565882] Oops: invalid opcode: 0000 [#1] SMP PTI
Set jit_required as true when insn_array map is used in the prog in
order to disallow interpreter fallback for gotox insn in
core.c::__bpf_prog_select_runtime().
Fixes: 493d9e0d60 ("bpf, x86: add support for indirect jumps")
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Link: https://lore.kernel.org/bpf/20260715141122.15783-3-leon.hwang@linux.dev
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Since the interpreter does not support the arena-related insns,
interpreter fallback should not be allowed for these insns in
core.c::__bpf_prog_select_runtime().
Currently, when the interpreter executes the arena ST/LDX/STX insns,
it would hit the BUG_ON() in ___bpf_prog_run() at run time.
[ 2.579196] BPF interpreter: unknown opcode a2 (imm: 0x0)
[ 2.579998] ------------[ cut here ]------------
[ 2.580652] kernel BUG at kernel/bpf/core.c:2349!
[ 2.581314] Oops: invalid opcode: 0000 [#1] SMP PTI
Set jit_required as true when arena map is used in the prog to disallow
interpreter fallback for arena-related insns.
Fixes: 6082b6c328 ("bpf: Recognize addr_space_cast instruction in the verifier.")
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Link: https://lore.kernel.org/bpf/20260715141122.15783-2-leon.hwang@linux.dev
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Yiyang Chen says:
====================
bpf: Reject arena frees below the arena base
bpf_arena_free_pages() can be called with a scalar arena address. The
runtime reconstructs a full user address from the arena base and the low
32 bits before returning the range to the arena free tree. A scalar one
page below the arena base can otherwise produce an out-of-domain free-tree
offset and make a later allocation return an address below the arena
mapping.
Patch 1 rejects frees whose reconstructed full user address is below
user_vm_start. Patch 2 adds verifier_arena coverage for the
scalar-below-base case.
Changes in v2:
- Add Reviewed-by tags from Emil Tsalapatis.
- Remove the empty inline asm from the selftest.
v1: https://lore.kernel.org/bpf/cover.1782813442.git.chenyy23@mails.tsinghua.edu.cn/
====================
Link: https://patch.msgid.link/20260717-c10-031-public-bpf-next-v2-b4-v2-0-54b555443a7c@mails.tsinghua.edu.cn
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
bpf_arena_free_pages() accepts scalar arena addresses. The runtime
masks the address to the low 32 bits and reconstructs a full user
address from the arena base before returning the range to the arena
free tree.
When the scalar value is below the low 32 bits of the arena base,
full_uaddr falls below user_vm_start. The existing upper-end clipping
then turns this into an out-of-range free-tree offset. A later
allocation can reuse that offset and return an address below the arena
mapping.
Reject such frees before computing the clipped range.
Fixes: 317460317a ("bpf: Introduce bpf_arena.")
Signed-off-by: Yiyang Chen <chenyy23@mails.tsinghua.edu.cn>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/bpf/20260717-c10-031-public-bpf-next-v2-b4-v2-1-54b555443a7c@mails.tsinghua.edu.cn
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
CONFIG_IPV6_SEG6_LWTUNNEL is currently enabled in each arch-specific
config fragment for the BPF selftests. Commit 33a971d549
("selftests/bpf: Add LWT encap tests for skb metadata") has enabled this
config in the generic config as well, resulting in a small warning when
configuring a kernel for selftests:
$ cat tools/testing/selftests/bpf/{config,config.vm,config.x86_64}>.config
$ make olddefconfig
HOSTCC scripts/kconfig/conf.o
HOSTCC scripts/kconfig/confdata.o
HOSTLD scripts/kconfig/conf
config:269:warning: override: reassigning to symbol IPV6_SEG6_LWTUNNEL
#
# configuration written to .config
#
Now that IPV6_SEG6_LWTUNNEL is set in the general config fragment, drop
it from the arch-specific fragments.
Signed-off-by: Alexis Lothoré (eBPF Foundation) <alexis.lothore@bootlin.com>
Link: https://lore.kernel.org/bpf/20260709-testing-fragments-v1-1-65244b0650ff@bootlin.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Jiayuan Chen says:
====================
bpf: Add memory usage for arena and selftest
arena is the only map type whose map_mem_usage() still returns 0, so
bpftool and fdinfo always show 0 memlock for it no matter how many pages
it holds. This series adds the accounting, runs the arena selftests
serially so they don't OOM a small CI VM, and adds a test for it.
v1 -> v2:
- split the scratch_page -> arena refactor into a prep patch (no
functional change)
- use WRITE_ONCE() for nr_pages to pair with the lockless reader
- reword the "run serially" commit message
- selftest: alloc prog returns 0 so the failure check is reached
v1: https://lore.kernel.org/bpf/20260716142746.8794-1-jiayuan.chen@linux.dev/
====================
Link: https://patch.msgid.link/20260717114117.350851-1-jiayuan.chen@linux.dev
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Allocate and free arena pages, both from BPF and via user-space fault-in,
and check that the map's memlock in fdinfo tracks the number of pages that
are actually populated.
Like the other arena tests it runs serially.
test:
./test_progs -a arena_mem_usage
#5 arena_mem_usage:OK
Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/bpf/20260717114117.350851-5-jiayuan.chen@linux.dev
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Every arena reserves a 4GB kernel vmalloc region at creation, and on a
KASAN build that eagerly populates ~512MB of shadow memory per arena. When
several arena tests run in parallel their shadow adds up, exhausts the
memory of a small CI VM and trips the OOM killer during map creation.
Make the dedicated arena tests (arena_* and libarena*) serial so they no
longer pile up in the parallel phase. That alone brings the peak number of
live arenas back within the CI memory budget.
A few other tests such as verifier_arena*, stream and compute_live_registers
create an arena too, but they run inside shared RUN_TESTS()/RUN() suites, so
turning them serial would drag many unrelated subtests along with them.
Leave those as-is.
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/bpf/20260717114117.350851-4-jiayuan.chen@linux.dev
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
arena is the only map type whose map_mem_usage() still returns 0, so
"bpftool map show" and fdinfo always showed 0 memlock for an arena no
matter how many pages it had.
Count the pages that are actually mapped into the arena: bump a counter in
apply_range_set_cb() when a page goes in and drop it in
apply_range_clear_cb() when a page goes out, both under the arena spinlock.
map_mem_usage() then just returns nr_pages << PAGE_SHIFT.
Only real data pages are counted, not the scratch page.
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/bpf/20260717114117.350851-3-jiayuan.chen@linux.dev
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
check_kfunc_call() reads meta.func_name when bpf_fetch_kfunc_arg_meta()
returns -EACCES, but that error can come from fetch_kfunc_meta() (e.g.
fd_array_get_btf() rejecting BTF binding for a signed program) before
meta is memset(), leaving it uninitialized and risking a garbage deref
in verbose().
Move the memset() to the start of bpf_fetch_kfunc_arg_meta() so meta is
zeroed on every error return. The intended "not allowed" -EACCES path
still sets func_name first, so its message is unchanged.
Signed-off-by: Amery Hung <ameryhung@gmail.com>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://patch.msgid.link/20260715172127.2416388-3-ameryhung@gmail.com
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
For a bloom filter, the value argument of bpf_map_peek_elem() is always
an input. Therefore, the verifier should not allow passing uninitialized
stack memory to it to avoid information leak.
bpf_map_peek_elem() tags its value argument ARG_PTR_TO_MAP_VALUE |
MEM_UNINIT, telling the verifier the callee fills the buffer. This holds
for queue/stack maps, but not for a bloom filter, which reads the buffer
as an input to test set membership and never writes it.
As a result, a program can pass an uninitialized stack buffer to
bpf_map_peek_elem() on a bloom filter. The verifier accepts it and marks
the buffer initialized on return, letting the program read back leftover
kernel stack memory. Bloom maps require CAP_BPF to create, so this is a
CAP_BPF-gated stack infoleak that bypasses the boundary CAP_BPF is meant
to enforce (arbitrary kernel reads are gated behind CAP_PERFMON).
Signed-off-by: Amery Hung <ameryhung@gmail.com>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://patch.msgid.link/20260715172127.2416388-2-ameryhung@gmail.com
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Pull bpf fixes from Kumar Kartikeya Dwivedi:
- Fix a UAF in socket clone early bailout paths (Matt Bobrowski)
- Reject unhashed UDP sockets on sockmap update to prevent refcount
leaks (Michal Luczaj)
- Account for receive queue data in FIONREAD on sockmap sockets without
a verdict program (Mattia Meleleo)
- Reject negative constant offsets for verifier buffer pointers (Sun
Jian)
- Fix for tracing of kfuncs with implicit arguments (Ihor Solodrai)
* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
selftests/bpf: Cover tracing implicit kfunc args
bpf: Fix tracing of kfuncs with implicit args
selftests/bpf: Cover negative buffer pointer offsets
bpf: Reject negative const offsets for buffer pointers
selftests/bpf: Test FIONREAD on a sockmap socket without a verdict program
bpf, sockmap: Account for receive queue in FIONREAD without a verdict program
selftests/bpf: Fail unbound UDP on sockmap update
selftests/bpf: Adapt sockmap update error handling
bpf, sockmap: Reject unhashed UDP sockets on sockmap update
selftests/bpf: Ensure UDP sockets are bound
bpf: Fix UAF in sock clone early bailouts
Pull selinux fix from Paul Moore:
"A single SELinux patch to correct a problem with the overlayfs mmap()
and mprotect() fixes from earlier this year where we inadvertenly
included an additional SELinux execmem permission check on some
operations"
* tag 'selinux-pr-20260717' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
selinux: fix incorrect execmem checks on overlayfs
Pull crypto library fixes from Eric Biggers:
- Fix a build error in certain configurations
- Clarify some parts of the documentation
- Remove unused code that I forgot to remove in commit cf52058dcd
("lib/crypto: powerpc/md5: Drop powerpc optimized MD5 code")
* tag 'libcrypto-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux:
crypto: aes - Fix conditions for selecting MAC dependencies
lib/crypto: docs: Improve introduction sentence
lib/crypto: docs: Fix some sentence fragments
lib/crypto: md5: Remove support for md5_mod_init_arch()
Pull mtd fixes from Miquel Raynal:
"Among the most important fixes that we have here, there are:
- the revert of the uclinux map driver which was presumed to
be no longer used but in fact was
- the use of SPI match data to get chip capabilities in the
mchp23k256 driver
- several fixes addressing the newly introduced virt-concat
support
- a missing build dependency on ndfc
as well as the usual load (if not actually bigger than usual) of
uninitialized variables, leaks, double free, and AI fuzzed issues
being fixed"
* tag 'mtd/fixes-for-7.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux:
Revert "mtd: maps: remove uclinux map driver"
mtd: onenand: samsung: report DMA completion timeouts
mtd: rawnand: fsl_ifc: return errors for failed page reads
mtd: mchp23k256: use SPI match data for chip caps
mtd: rawnand: lpc32xx_slc: fail DMA transfer on completion timeout
mtd: rawnand: lpc32xx_mlc: fail DMA transfers on timeout
mtd: fix double free and WARN_ON in add_mtd_device() error paths
mtd: virt-concat: free duplicate generated name
mtd: nand: mtk-ecc: stop on ECC idle timeouts
mtd: mtdswap: remove debugfs stats file on teardown
mtd: mtdpart: validate partition bounds in mtd_add_partition()
mtd: mtdpart: fix uninitialized erasesize on MTDPART_OFS_RETAIN error path
mtd: rawnand: ndfc: add CONFIG_OF dependency
mtd: spinand: initialize ret in regular page reads
mtd: virt_concat: fix use-after-free in mtd_virt_concat_destroy()
mtd: rawnand: ingenic: handle ECC clock enable failures
mtd: nand: ecc-mtk: handle ECC clock enable failures
mtd: virt_concat: fix use-after-free in mtd_virt_concat_destroy_joins()
mtd: rawnand: ndfc: fix gcc uninitialized var
Pull MMC fixes from Ulf Hansson:
"MMC core:
- Fix RPMB device unregister ordering
- Fix __counted_by handling in mmc_test
MMC host:
- mtk-sd: Document missing clocks for MT8189
- sdhci-esdhc-imx: Fix the support for system suspend/resume for SDIO
- sdhci-of-dwcmshc: Fix error handling for clock prepare/enable
- vub300:
- Fix lockdep issue for the cmd_mutex
- Fix use-after-free on probe failure
MEMSTICK:
- Reject a card that reports too many blocks"
* tag 'mmc-v7.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
mmc: sdhci-esdhc-imx: fix resume error handling
mmc: sdhci-esdhc-imx: make non-fatal errors non-blocking in suspend
mmc: sdhci-esdhc-imx: use pm_runtime_resume_and_get() in suspend
mmc: sdhci-esdhc-imx: disable irq during suspend to fix unhandled interrupt
mmc: sdhci-esdhc-imx: restore pinctrl before restoring ios timing on resume
mmc: sdhci-esdhc-imx: fix esdhc_change_pinstate() to allow default state restore
mmc: sdhci-esdhc-imx: restore DLL override for DDR modes on resume
mmc: sdhci-esdhc-imx: remove unnecessary mmc_card_wake_sdio_irq check for tuning save/restore
mmc: block: fix RPMB device unregister ordering
memstick: ms_block: reject a card that reports too many blocks
dt-bindings: mmc: mtk-sd: Document extra clocks for MT8189
mmc: vub300: defer reset until cmd_mutex is unlocked
mmc: vub300: fix use-after-free on probe failure
mmc: mmc_test: Fix __counted_by handling after kzalloc_flex() conversion
mmc: sdhci-of-dwcmshc: check bus clock enable result in the probe() method
Pull SoC fixes from Arnd Bergmann:
"There are only three devicetree fixes this time: one critical memory
corruption fix for Renesas and three minor corrections for Tegra.
The MAINTAINERS file is updated for a new maintainer of the CIX
platform and two address changes.
The rest is all driver fixes, mostly firmware:
- multiple runtime issues in ARM SCMI and FF-A firmware code, dealing
with error handling for corner cases in firmware.
- multiple fixes for reset drivers, dealing with individual platform
specific mistakes and more error handling
- minor build and runtime fixes for the Tegra SoC drivers"
* tag 'soc-fixes-7.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
arm64: dts: renesas: ironhide: Describe inline ECC carveouts
MAINTAINERS: Update maintainer and git tree for CIX SoC
ARM: Don't let ARMv5 platforms select USE_OF
MAINTAINERS: Update SpacemiT SoC git tree repository
firmware: arm_scmi: Rate-limit queue-full warnings in IRQ context
firmware: arm_scmi: Use 64-bit division for clock rate rounding
reset: imx7: Correct polarity of MIPI CSI resets on i.MX8MQ
reset: sunxi: fix memory region leak on ioremap failure
dt-bindings: reset: altr: add COMBOPHY_RESET for Agilex5
reset: spacemit: k3: fix USB2 ahb reset
firmware: arm_scmi: Grammar s/may needed/may be needed/
firmware: arm_ffa: Fix NULL dereference in ffa_partition_info_get()
firmware: arm_ffa: Respect firmware advertised RX/TX buffer size limits
arm64: tegra: Fix CPU1 node unit-address on Tegra264
arm64: tegra: Fix CPU compatible string to cortex-a78ae on Tegra234
MAINTAINERS: .mailmap: update Jens Wiklander's email address
soc/tegra: fuse: Fix spurious straps warning on SMCCC platforms
soc/tegra: pmc: fix #ifdef block in header
drm/tegra: Fix a strange error handling path
arm64: tegra: Remove fallback compatible for GPCDMA
Pull powerpc fixes from Madhavan Srinivasan:
- Enable CONFIG_VPA_PMU to be used with KVM
- Initialize starttime at boot for native accounting
- Set CPU_FTR_P11_PVR for Power11 and later processors
- fix memory leak on krealloc failure in papr_init
- Misc fixes and cleanups
Thanks to Amit Machhiwal, Christophe Leroy (CS GROUP), Ethan
Nelson-Moore, Gautam Menghani, Harsh Prateek Bora, Junrui Luo, Mukesh
Kumar Chaurasiya (IBM), Ritesh Harjani (IBM), Rosen Penev, Shrikanth
Hegde, Thorsten Blum, and Yuhao Jiang
* tag 'powerpc-7.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc: Remove dead non-preemption code
powerpc/dt_cpu_ftrs: Set CPU_FTR_P11_PVR for Power11 and later processors
powerpc/pseries: fix memory leak on krealloc failure in papr_init
powerpc/uaccess: correct check for CONFIG_PPC_E500 in mask_user_address()
powerpc/vtime: Initialize starttime at boot for native accounting
powerpc/85xx: Add fsl,ifc to common device ids
powerpc/spufs: fix out-of-bounds access in spufs_mem_mmap_access()
powerpc/pseries/Kconfig: Enable CONFIG_VPA_PMU to be used with KVM
On CONFIG_INET=n builds, mpls_valid_fib_dump_req() walks the parsed
attribute table itself instead of calling ip_valid_fib_dump_req(). The
RTA_OIF arm passes tb[RTA_OIF] to nla_get_u32() without checking it is
present, so an RTM_GETROUTE dump for AF_MPLS with strict checking and no
RTA_OIF hits a NULL dereference.
RTM_GETROUTE is RTNL_KIND_GET, which rtnetlink_rcv_msg() permits without
CAP_NET_ADMIN, so an unprivileged user can trigger it.
Oops: general protection fault, probably for non-canonical address
0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
RIP: 0010:mpls_valid_fib_dump_req (net/mpls/af_mpls.c:2189)
Call Trace:
mpls_dump_routes (net/mpls/af_mpls.c:2236)
netlink_dump (net/netlink/af_netlink.c:2331)
__netlink_dump_start (net/netlink/af_netlink.c:2446)
rtnetlink_rcv_msg (net/core/rtnetlink.c:7033)
netlink_rcv_skb (net/netlink/af_netlink.c:2556)
netlink_unicast (net/netlink/af_netlink.c:1345)
netlink_sendmsg (net/netlink/af_netlink.c:1900)
__sock_sendmsg (net/socket.c:790)
____sys_sendmsg (net/socket.c:2684)
___sys_sendmsg (net/socket.c:2738)
__sys_sendmsg (net/socket.c:2770)
do_syscall_64 (arch/x86/entry/syscall_64.c:94)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)
Skip unset attributes, as ip_valid_fib_dump_req() does.
Fixes: 196cfebf89 ("net/mpls: Handle kernel side filtering of route dumps")
Assisted-by: Claude:claude-opus-4-8
Reported-by: Xiang Mei <xmei5@asu.edu>
Signed-off-by: Weiming Shi <bestswngs@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20260711114958.1009619-3-bestswngs@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
llc_sap_add_socket() takes a SAP reference for each socket added to a SAP,
and llc_sap_remove_socket() releases it. llc_create_incoming_sock() takes
an additional SAP reference after adding the child socket.
This extra reference was balanced by an explicit llc_sap_put() in
llc_ui_release() until commit 3100aa9d74 ("llc: fix SAP reference
counting w.r.t. socket handling") removed that put. The corresponding hold
in the accept path was left behind.
When such a child socket is removed, only the reference taken by
llc_sap_add_socket() is released. The extra reference keeps the SAP alive
after its last socket is removed. Remove the obsolete hold.
Fixes: 3100aa9d74 ("llc: fix SAP reference counting w.r.t. socket handling")
Cc: stable@vger.kernel.org
Signed-off-by: Xuanqiang Luo <luoxuanqiang@kylinos.cn>
Link: https://patch.msgid.link/20260712130343.518797-1-xuanqiang.luo@linux.dev
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
bnxt_aux_devices_init() calls auxiliary_device_init() before all fields
used by bnxt_aux_dev_release() are initialized. After
auxiliary_device_init() succeeds, later errors must unwind with
auxiliary_device_uninit(), which invokes the release callback.
The release callback assumes that aux_priv->id, aux_priv->edev,
edev->net and edev->ulp_tbl are all populated. If allocation fails
after auxiliary_device_init(), the release path can otherwise dereference
or clear partially initialized state.
Allocate and attach the bnxt_en_dev and ULP table before calling
auxiliary_device_init(), so the release callback only sees a fully
initialized auxiliary private object. If auxiliary_device_init() itself
fails, free those allocations directly because device_initialize() has not
run and the release callback will not be invoked.
This issue was found by a static analysis checker and confirmed by manual
source review.
Fixes: 194fad5b27 ("bnxt_en: Refactor bnxt_rdma_aux_device_init/uninit functions")
Signed-off-by: Ruoyu Wang <ruoyuw560@gmail.com>
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Link: https://patch.msgid.link/20260711163716.3996929-1-ruoyuw560@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The auth_hmacs array in struct sctp_cookie is supposed to store a complete
SCTP_AUTH_HMAC_ALGO parameter, which consists of a struct sctp_paramhdr
followed by N HMAC identifiers.
However, the array size was calculated using an extra 2 bytes instead of
sizeof(struct sctp_paramhdr), which is 4 bytes. When four HMAC identifiers
are configured, the HMAC-ALGO parameter stored in the endpoint is larger
than the auth_hmacs buffer in the cookie.
As a result, sctp_association_init() copies beyond the end of auth_hmacs
when initializing the association, corrupting the adjacent auth_chunks
field. This can lead to an invalid HMAC identifier being accepted and later
cause an out-of-bounds read in sctp_auth_get_hmac().
Fix the array size calculation by including the full SCTP parameter header
size.
Fixes: 1f485649f5 ("[SCTP]: Implement SCTP-AUTH internals")
Reported-by: Yuan Tan <yuantan098@gmail.com>
Reported-by: Xin Liu <dstsmallbird@foxmail.com>
Reported-by: Zihan Xi <xizh2024@lzu.edu.cn>
Reported-by: Ren Wei <enjou1224z@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/634a0de0d5de29532915e6d47c92a0cbc206e03f.1783707155.git.lucien.xin@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
When a dpll_pin is shared across multiple dpll_device instances and
those devices are being unregistered (e.g. during driver module removal),
a NULL pointer dereference can occur in dpll_msg_add_pin_ref_sync().
This happens under the following conditions:
- A pin is registered with two or more dpll devices (dpll_A, dpll_B)
- The pin has ref_sync pairs with other pins
- During unregistration of dpll_A's pins, a ref_sync partner pin is
unregistered first, removing it from dpll_A->pin_refs
- But since the partner pin is still registered with dpll_B, its
dpll_refs is not empty, so dpll_pin_ref_sync_pair_del() does NOT
run and the partner stays in the pin's ref_sync_pins xarray
- When the pin itself is then unregistered from dpll_A, the delete
notification calls dpll_msg_add_pin_ref_sync() which finds the
partner in ref_sync_pins, passes dpll_pin_available() (partner is
still registered with dpll_B), but dpll_pin_on_dpll_priv(dpll_A,
partner) returns NULL because partner was already removed from
dpll_A->pin_refs
- The NULL priv pointer is passed to the driver's ref_sync_get
callback, which dereferences it
BUG: kernel NULL pointer dereference, address: 0000000000000034
Oops: Oops: 0000 [#1] SMP NOPTI
RIP: 0010:zl3073x_dpll_input_pin_ref_sync_get+0x73/0x80 [zl3073x]
Call Trace:
dpll_msg_add_pin_ref_sync+0xb8/0x200
dpll_cmd_pin_get_one+0x3b6/0x4b0
dpll_pin_event_send+0x72/0x140
__dpll_pin_unregister+0x5a/0x2b0
dpll_pin_unregister+0x49/0x70
Fix this by skipping ref_sync pins whose priv pointer cannot be resolved
for the current dpll device.
Fixes: 58256a26bf ("dpll: add reference sync get/set")
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://patch.msgid.link/20260710193625.1378822-1-ivecera@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Workloads that repeatedly allocate and release mkeys carrying TPH
steering-tag hints (e.g. churning RDMA MRs) leak one
struct mlx5_st_idx_data per cycle; kmemleak flags it as unreferenced
and the kmalloc slab grows over time.
When the last reference to an ST table entry is dropped,
mlx5_st_dealloc_index() removed the entry from idx_xa but the backing
mlx5_st_idx_data allocation was never freed.
Free idx_data after the xa_erase() so the lifetime of the bookkeeping
struct matches the lifetime of the ST entry it tracks.
Cc: stable@vger.kernel.org
Fixes: 888a7776f4 ("net/mlx5: Add support for device steering tag")
Reviewed-by: Michael Gur <michaelgur@nvidia.com>
Signed-off-by: Zhiping Zhang <zhipingz@meta.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/20260702222507.1234467-1-zhipingz@meta.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Marc Kleine-Budde says:
====================
pull-request: can 2026-07-16
this is a pull request of 19 patches for net/main.
The first patch is by Alexander Hölzl and fixes the Kconfig
description of the vxcan driver.
Next patch by Fan Wu fixes the tear down order in the esd_usb driver.
Followed by a patch by Oliver Hartkopp that adds missing locking for
the raw flags in the CAN_RAW protocol.
Shuhao Fu's patch for the j1939 protocol fix lockless
local-destination check.
Stéphane Grosjean updates their email address.
The next 11 patches all target the CAM Broadcast Manager protocol. One
contributed by Lee Jones the remaining ones by Oliver Hartkopp. They
fix several concurrency and locking issues found by various bots.
The last 3 patches are also by Oliver Hartkopp fixing concurrency and
locking issues found by various bots in the CAN ISO Transport
Protocol.
linux-can-fixes-for-7.2-20260716
* tag 'linux-can-fixes-for-7.2-20260716' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can:
can: isotp: serialize TX state transitions under so->rx_lock
can: isotp: fix use-after-free race with concurrent NETDEV_UNREGISTER
can: isotp: use unconditional synchronize_rcu() in isotp_release()
can: bcm: track a single source interface for ANYDEV timeout/throttle ops
can: bcm: fix data race on rx_stamp/rx_ifindex in bcm_rx_handler()
can: bcm: fix stale rx/tx ops after device removal
can: bcm: add missing device refcount for CAN filter removal
can: bcm: validate frame length in bcm_rx_setup() for RTR replies
can: bcm: extend bcm_tx_lock usage for data and timer updates
can: bcm: add missing rcu list annotations and operations
can: bcm: fix CAN frame rx/tx statistics
can: bcm: add locking when updating filter and timer values
can: bcm: fix lockless bound/ifindex race and silent RX_SETUP failure
can: bcm: defer rx_op deallocation to workqueue to fix thrtimer UAF
can: peak: Modification of references to email accounts being deleted
can: j1939: fix lockless local-destination check
can: raw: add locking for raw flags bitfield
can: esd_usb: kill anchored URBs before freeing netdevs
can: vxcan: Kconfig: fix description stating no local echo provided
====================
Link: https://patch.msgid.link/20260716155528.809908-1-mkl@pengutronix.de
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Florian Westphal says:
====================
netfilter: updates for net
The following patchset contains Netfilter fixes for *net*.
These are fixes for bugs except patches 6 and 9 which fix issues added in
last PR and 7.1-rc1.
1) Reject unsupported target families in xt_nat_checkentry().
From Wyatt Feng.
2) Fix inverted time_after() check in ecache_work_evict_list().
Causes pointless work rescheds and thus way longer time to
clear the pending event backlog. From Yizhou Zhao.
3) Fix a use-after-free in br_ip6_fragment() caused by a dangling prevhdr
pointer. From Xiang Mei.
4) Fix incorrect conntrack zone comparison in nf_conncount tuple
deduplication. Pass IP_CT_DIR_ORIGINAL, not zone direction.
From Yizhou Zhao.
5) Add bridge tunnel flowtable regression test for a bug that
got fixed in the previous PR. From Zhengyang Chen.
6) Use the correct direction when setting up tunnel routes in the flowtable
xmit path. From Pablo Neira Ayuso. This fixes a bug added in the
previous PR.
7) Reload IP header after potential skb head reallocation in IPVS.
8) Fix incorrect IPv6 transport offsets in TCP application code. Correct the
ICMPv6 header offset to ensure proper checksumming with extension headers,
from Julian Anastasov. this is a followup to the previous PR.
9) Remove null-termination requirement for xt_physdev masks, this broke
device names with 15 characters.
netfilter pull request nf-26-07-10
* tag 'nf-26-07-10' of https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
netfilter: xt_physdev: masks are not c-strings
ipvs: fix more places with wrong ipv6 transport offsets
ipvs: reload ip header after head reallocation
netfilter: flowtable: use correct direction to set up tunnel route
selftests: netfilter: add bridge tunnel flowtable regression
netfilter: nf_conncount: fix zone comparison in tuple dedup
netfilter: bridge: fix stale prevhdr pointer in br_ip6_fragment()
netfilter: ecache: fix inverted time_after() check
netfilter: xt_nat: reject unsupported target families
====================
Link: https://patch.msgid.link/20260710143733.29741-1-fw@strlen.de
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Some JIT compilers, such as x86_64, rely on a register to pass the TCC.
When subprograms of synchronous callback invoke tailcall, C helpers
invoking bpf callback clobber this register, and the corrupted TCC may
bypass the TCC limit, leading to infinite tailcall.
Fix this by rejecting tailcall inside all subprogs of sync callback.
This also cleanly consolidates the existing async and exception callback
checks into a single unified `is_cb` check.
Reported-by: Sashiko <sashiko-bot@kernel.org>
Reported-by: Björn Töpel <bjorn@kernel.org>
Signed-off-by: Pu Lehui <pulehui@huawei.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://patch.msgid.link/20260716120157.835937-3-pulehui@huaweicloud.com
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Currently in check_max_stack_depth_subprog, when the verifier enters a
new callee branch, the local tail_call_reachable is not properly
synchronized with the callee's state.
Consider a main prog branching into multiple subprogs:
subprog0 -> tailcall
main <
subprog1 -> subprog2
When the verifier finishes checking subprog0 and backtracks to main
prog, the local tail_call_reachable state is left as true. As it
proceeds to subprog1, this uncleared state leaks into the new branch,
falsely marking subprog1 and subprog2 as tailcall reachable.
Fix this by explicitly syncing tail_call_reachable with the callee's
has_tail_call state on entry. The caller's state is safely preserved and
restored via the existing backtracking logic.
Fixes: ebf7d1f508 ("bpf, x64: rework pro/epilogue and tailcall handling in JIT")
Reported-by: Sashiko <sashiko-bot@kernel.org>
Signed-off-by: Pu Lehui <pulehui@huawei.com>
Link: https://patch.msgid.link/20260716120157.835937-2-pulehui@huaweicloud.com
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Pull smb client fixes from Steve French:
- fallocate fixes
- unit test fixes
- fix allocation size after duplicate extents
- fix check for overlapping data areas
* tag 'v7.2-rc3-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
smb/client: flush dirty data before punching a hole
smb/client: Use EXPORT_SYMBOL_IF_KUNIT() to export symbols in SMB2
smb/client: Use EXPORT_SYMBOL_IF_KUNIT() to export symbols
smb: client: reject overlapping data areas in SMB2 responses
smb/client: refresh allocation after EOF-extending fallocate
smb/client: emulate small EOF-extending mode 0 fallocate ranges
smb/client: reduce fallocate zero buffer allocation
smb/client: handle overlapping allocated ranges in fallocate
smb/client: refresh allocation size after duplicate extents
smb: client: use kvzalloc() for megabyte buffer in simple fallocate
Ihor Solodrai says:
====================
bpf: Fix tracing of kfuncs with implicit args
Tejun reported an issue where a BPF program tracing a kfunc with
KF_IMPLICIT_ARGS can crash the kernel [1]. This is caused by a bug in
bpf_check_attach_target(): the btf_func_model for such a kfunc is
computed from a wrong BTF prototype. For more details see the commit
message of patch #1.
The second patch adds a selftest that can catch this situation.
The fix is a candidate for 7.1 backport.
[1] https://github.com/sched-ext/scx/issues/3687#issuecomment-4906694106
---
v2->v3:
* Replace btf_kfunc_accumulated_flags() with btf_kfunc_check_flag()
following a discussion with Eduard. Inlining the hook walk is a
worse option than a helper, because BTF_KFUNC_HOOK_MAX and co are
internal to btf.c and exposing them is uglier.
* remove reduntant btf_is_func check (Jiri)
* formatting nit (Eduard)
v2: https://lore.kernel.org/bpf/20260710192940.3020280-1-ihor.solodrai@linux.dev/
v1->v2:
* Take a module reference in btf_attach_func_proto() around the
btf_kfunc_accumulated_flags() call (sashiko)
v1: https://lore.kernel.org/bpf/20260710005902.2234832-1-ihor.solodrai@linux.dev/
---
====================
Link: https://patch.msgid.link/20260713235223.1639022-1-ihor.solodrai@linux.dev
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
KF_IMPLICIT_ARGS kfuncs have a BPF-call prototype and a real kernel
target prototype. Add a tracing selftest that attaches fentry and fexit
programs to bpf_kfunc_implicit_arg(), runs a syscall BPF program that
calls it, and checks that the tracing context exposes both the explicit
argument and the implicit prog aux pointer.
Co-developed-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Link: https://patch.msgid.link/20260713235223.1639022-3-ihor.solodrai@linux.dev
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
A kfunc marked with KF_IMPLICIT_ARGS flag takes implicit arguments
(such as bpf_prog_aux) that the verifier injects at load time.
resolve_btfids strips those from the kfunc's BTF-visible prototype and
keeps the real kernel ABI in a counterpart _impl prototype [1].
fentry/fexit/fmod_ret/fsession programs may attach to the BPF kernel
functions, including those with implicit args. However
bpf_check_attach_target() and bpf_check_attach_btf_id_multi() extract
the struct btf_func_model from the wrong BTF prototype of the
kfunc. The btf_func_model is later read to construct the trampoline,
which then causes the injected implicit argument to be clobbered and
the kfunc dereferencing garbage.
Add btf_attach_func_proto() to resolve the real ABI prototype of the
kfunc the way the call site does: by looking up the _impl prototype
for a KF_IMPLICIT_ARGS kfunc. Use it at both attach-target model
construction sites.
To enable this, make two supporting changes:
* pass bpf_verifier_log instead of bpf_verifier_env to
find_kfunc_impl_proto(), so it can be reused from the attach path
* add btf_kfunc_check_flag() to test a flag across all of a kfunc's
hook sets, because a program attaching to a kfunc is not in the
kfunc's call-set
KF_IMPLICIT_ARGS must be consistent across the sets, so
btf_kfunc_check_flag() returns -EINVAL on inconsistency.
btf_kfunc_check_flag() reads the kfunc's flags from the target's
kfunc_set_tab. For a module BTF that table is stable only after the
module is live, so take a module reference around the read, mirroring
how the kfunc call path gates the same lookup with btf_try_get_module().
The remaining call sites of btf_distill_func_proto() are safe as
is. The BPF_TRACE_ITER case distills a registered iterator's
prototype, and bpf_struct_ops_desc_init() distills the
function-pointer members of a struct_ops type. Neither is a kfunc, and
so can't have implicit arguments.
[1] https://lore.kernel.org/all/20260120222638.3976562-1-ihor.solodrai@linux.dev/
Fixes: 64e1360524 ("bpf: Verifier support for KF_IMPLICIT_ARGS")
Reported-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Link: https://github.com/sched-ext/scx/issues/3687#issuecomment-4906694106
Link: https://patch.msgid.link/20260713235223.1639022-2-ihor.solodrai@linux.dev
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
