kernel/linux.git/lib, branch v6.12.92

test_kprobes: clear kprobes between test runs

2026-06-01T15:46:25+00:00

[ Upstream commit ef5581bb30efb939cc2bf093475c6cc85258e5cd ] Running the kprobes sanity tests twice makes all tests fail and eventually crashes the kernel. [root@martin-riscv-1 ~]# echo 1 > /sys/kernel/debug/kunit/kprobes_test/run ... # Totals: pass:5 fail:0 skip:0 total:5 ok 1 kprobes_test [root@martin-riscv-1 ~]# echo 1 > /sys/kernel/debug/kunit/kprobes_test/run ... # test_kprobe: EXPECTATION FAILED at lib/tests/test_kprobes.c:64 Expected 0 == register_kprobe(&kp), but register_kprobe(&kp) == -22 (0xffffffffffffffea) ... Unable to handle kernel paging request ... The testsuite defines several kprobes and kretprobes as static variables that are preserved across test runs. After register_kprobe and unregister_kprobe, a kprobe contains some leftover data that must be cleared before the kprobe can be registered again. The tests are setting symbol_name to define the probe location. Address and flags must be cleared. The existing code clears some of the probes between subsequent tests, but not between two test runs. The leftover data from a previous test run makes the registrations fail in the next run. Move the cleanups for all kprobes into kprobes_test_init, this function is called before each single test (including the first test of a test run). Link: https://lore.kernel.org/all/20260507134615.1010905-1-martin@kaiser.cx/ Fixes: e44e81c5b90f ("kprobes: convert tests to kunit") Signed-off-by: Martin Kaiser Signed-off-by: Masami Hiramatsu (Google) Signed-off-by: Sasha Levin

kunit: config: KUNIT_DEBUGFS should depend on DEBUG_FS

2026-06-01T15:46:24+00:00

[ Upstream commit 8f80b5b227ef9ea422080487715c841856339aed ] CONFIG_KUNIT_DEBUGFS is totally useless without debugfs, so it should depend on CONFIG_DEBUG_FS. Link: https://lore.kernel.org/r/20260425034155.53913-2-david@davidgow.net Fixes: e2219db280e3 ("kunit: add debugfs /sys/kernel/debug/kunit//results display") Signed-off-by: David Gow Signed-off-by: Shuah Khan Signed-off-by: Sasha Levin

kunit: config: Enable KUNIT_DEBUGFS by default

2026-06-01T15:46:24+00:00

[ Upstream commit 17e4c68ff35090d8cb743e3c82c09f92fda1ebda ] The KUNIT_DEBUGFS option is currently enabled based on the value of KUNIT_ALL_TESTS, but it really doesn't have anything to do with the set of enabled tests, so just enable it by default anyway. In particular, this shouldn't be only visible if KUNIT_ALL_TESTS is set, which is quite confusing. Link: https://lore.kernel.org/r/20260425034155.53913-1-david@davidgow.net Fixes: beaed42c427d ("kunit: default KUNIT_* fragments to KUNIT_ALL_TESTS") Signed-off-by: David Gow Signed-off-by: Shuah Khan Signed-off-by: Sasha Levin

net, treewide: define and use MAC_ADDR_STR_LEN

2026-05-23T11:04:54+00:00

[ Upstream commit 6d6c1ba7824022528dbe3e283fafbd0775424128 ] There are a few places in the tree which compute the length of the string representation of a MAC address as 3 * ETH_ALEN - 1. Define a constant for this and use it where relevant. No functionality changes are expected. Signed-off-by: Uday Shankar Reviewed-by: Michal Swiatkowski Acked-by: Johannes Berg Reviewed-by: Breno Leitao Reviewed-by: Simon Horman Link: https://patch.msgid.link/20250312-netconsole-v6-1-3437933e79b8@purestorage.com Signed-off-by: Paolo Abeni Stable-dep-of: 3bc179bc7146 ("netpoll: fix IPv6 local-address corruption") Signed-off-by: Sasha Levin

lib/scatterlist: fix temp buffer in extract_user_to_sg()

2026-05-14T13:29:24+00:00

commit 118cf3f55975352ac357fb194405031458186819 upstream. Instead of allocating a temporary buffer for extracted user pages extract_user_to_sg() uses the end of the to be filled scatterlist as a temporary buffer. Fix the calculation of the start address if the scatterlist already contains elements. The unused space starts at sgtable->sgl + sgtable->nents not directly at sgtable->nents and the temporary buffer is placed at the end of this unused space. A subsequent commit will add kunit test cases that demonstrate that the patch is necessary. Pointed out by sashiko.dev on a previous iteration of this series. Link: https://lkml.kernel.org/r/20260326214905.818170-3-lk@c--e.de Fixes: 018584697533 ("netfs: Add a function to extract an iterator into a scatterlist") Signed-off-by: Christian A. Ehrhardt Cc: David Howells Cc: David Gow Cc: Kees Cook Cc: Petr Mladek Cc: [v6.5+] Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

lib/scatterlist: fix length calculations in extract_kvec_to_sg

2026-05-14T13:29:24+00:00

commit 07b7d66e65d9cfe6b9c2c34aa22cfcaac37a5c45 upstream. Patch series "Fix bugs in extract_iter_to_sg()", v3. Fix bugs in the kvec and user variants of extract_iter_to_sg. This series is growing due to useful remarks made by sashiko.dev. The main bugs are: - The length for an sglist entry when extracting from a kvec can exceed the number of bytes in the page. This is obviously not intended. - When extracting a user buffer the sglist is temporarily used as a scratch buffer for extracted page pointers. If the sglist already contains some elements this scratch buffer could overlap with existing entries in the sglist. The series adds test cases to the kunit_iov_iter test that demonstrate all of these bugs. Additionally, there is a memory leak fix for the test itself. The bugs were orignally introduced into kernel v6.3 where the function lived in fs/netfs/iterator.c. It was later moved to lib/scatterlist.c in v6.5. Thus the actual fix is only marked for backports to v6.5+. This patch (of 5): When extracting from a kvec to a scatterlist, do not cross page boundaries. The required length was already calculated but not used as intended. Adjust the copied length if the loop runs out of sglist entries without extracting everything. While there, return immediately from extract_iter_to_sg if there are no sglist entries at all. A subsequent commit will add kunit test cases that demonstrate that the patch is necessary. Link: https://lkml.kernel.org/r/20260326214905.818170-1-lk@c--e.de Link: https://lkml.kernel.org/r/20260326214905.818170-2-lk@c--e.de Fixes: 018584697533 ("netfs: Add a function to extract an iterator into a scatterlist") Signed-off-by: Christian A. Ehrhardt Cc: David Gow Cc: David Howells Cc: Kees Cook Cc: Petr Mladek Cc: [v6.5+] Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

lib/crypto: mpi: Fix integer underflow in mpi_read_raw_from_sgl()

2026-05-14T13:29:24+00:00

commit 8c2f1288250a90a4b5cabed5d888d7e3aeed4035 upstream. Yiming reports an integer underflow in mpi_read_raw_from_sgl() when subtracting "lzeros" from the unsigned "nbytes". For this to happen, the scatterlist "sgl" needs to occupy more bytes than the "nbytes" parameter and the first "nbytes + 1" bytes of the scatterlist must be zero. Under these conditions, the while loop iterating over the scatterlist will count more zeroes than "nbytes", subtract the number of zeroes from "nbytes" and cause the underflow. When commit 2d4d1eea540b ("lib/mpi: Add mpi sgl helpers") originally introduced the bug, it couldn't be triggered because all callers of mpi_read_raw_from_sgl() passed a scatterlist whose length was equal to "nbytes". However since commit 63ba4d67594a ("KEYS: asymmetric: Use new crypto interface without scatterlists"), the underflow can now actually be triggered. When invoking a KEYCTL_PKEY_ENCRYPT system call with a larger "out_len" than "in_len" and filling the "in" buffer with zeroes, crypto_akcipher_sync_prep() will create an all-zero scatterlist used for both the "src" and "dst" member of struct akcipher_request and thereby fulfil the conditions to trigger the bug: sys_keyctl() keyctl_pkey_e_d_s() asymmetric_key_eds_op() software_key_eds_op() crypto_akcipher_sync_encrypt() crypto_akcipher_sync_prep() crypto_akcipher_encrypt() rsa_enc() mpi_read_raw_from_sgl() To the user this will be visible as a DoS as the kernel spins forever, causing soft lockup splats as a side effect. Fix it. Reported-by: Yiming Qian # off-list Fixes: 2d4d1eea540b ("lib/mpi: Add mpi sgl helpers") Signed-off-by: Lukas Wunner Cc: stable@vger.kernel.org # v4.4+ Reviewed-by: Ignat Korchagin Reviewed-by: Jarkko Sakkinen Link: https://lore.kernel.org/r/59eca92ff4f87e2081777f1423a0efaaadcfdb39.1776003111.git.lukas@wunner.de Signed-off-by: Eric Biggers Signed-off-by: Greg Kroah-Hartman

lib: test_hmm: evict device pages on file close to avoid use-after-free

2026-05-07T04:09:43+00:00

[ Upstream commit 744dd97752ef1076a8d8672bb0d8aa2c7abc1144 ] Patch series "Minor hmm_test fixes and cleanups". Two bugfixes a cleanup for the HMM kernel selftests. These were mostly reported by Zenghui Yu with special thanks to Lorenzo for analysing and pointing out the problems. This patch (of 3): When dmirror_fops_release() is called it frees the dmirror struct but doesn't migrate device private pages back to system memory first. This leaves those pages with a dangling zone_device_data pointer to the freed dmirror. If a subsequent fault occurs on those pages (eg. during coredump) the dmirror_devmem_fault() callback dereferences the stale pointer causing a kernel panic. This was reported [1] when running mm/ksft_hmm.sh on arm64, where a test failure triggered SIGABRT and the resulting coredump walked the VMAs faulting in the stale device private pages. Fix this by calling dmirror_device_evict_chunk() for each devmem chunk in dmirror_fops_release() to migrate all device private pages back to system memory before freeing the dmirror struct. The function is moved earlier in the file to avoid a forward declaration. Link: https://lore.kernel.org/20260331063445.3551404-1-apopple@nvidia.com Link: https://lore.kernel.org/20260331063445.3551404-2-apopple@nvidia.com Fixes: b2ef9f5a5cb3 ("mm/hmm/test: add selftest driver for HMM") Signed-off-by: Alistair Popple Reported-by: Zenghui Yu Closes: https://lore.kernel.org/linux-mm/8bd0396a-8997-4d2e-a13f-5aac033083d7@linux.dev/ Reviewed-by: Balbir Singh Tested-by: Zenghui Yu Cc: David Hildenbrand Cc: Jason Gunthorpe Cc: Leon Romanovsky Cc: Liam Howlett Cc: Lorenzo Stoakes (Oracle) Cc: Michal Hocko Cc: Mike Rapoport Cc: Suren Baghdasaryan Cc: Zenghui Yu Cc: Matthew Brost Cc: Signed-off-by: Andrew Morton [ kept the existing simpler `dmirror_device_evict_chunk()` body instead of the upstream compound-folio version ] Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

lib/ts_kmp: fix integer overflow in pattern length calculation

2026-05-07T04:09:28+00:00

commit 8cdf30813ea8ce881cecc08664144416dbdb3e16 upstream. The ts_kmp algorithm stores its prefix_tbl[] table and pattern in a single allocation sized from the pattern length. If the prefix_tbl[] size calculation wraps, the resulting allocation can be too small and subsequent pattern copies can overflow it. Fix this by rejecting zero-length patterns and by using overflow helpers before calculating the combined allocation size. This fixes a potential heap overflow. The pattern length calculation can wrap during a size_t addition, leading to an undersized allocation. Because the textsearch library is reachable from userspace via Netfilter's xt_string module, this is a security risk that should be backported to LTS kernels. Link: https://lkml.kernel.org/r/20260308202028.2889285-2-objecting@objecting.org Signed-off-by: Josh Law Reviewed-by: Andrew Morton Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

x86-64/arm64/powerpc: clean up and rename __copy_from_user_flushcache

2026-04-22T11:19:02+00:00

commit 809b997a5ce945ab470f70c187048fe4f5df20bf upstream. This finishes the work on these odd functions that were only implemented by a handful of architectures. The 'flushcache' function was only used from the iterator code, and let's make it do the same thing that the nontemporal version does: remove the two underscores and add the user address checking. Yes, yes, the user address checking is also done at iovec import time, but we have long since walked away from the old double-underscore thing where we try to avoid address checking overhead at access time, and these functions shouldn't be so special and old-fashioned. The arm64 version already did the address check, in fact, so there it's just a matter of renaming it. For powerpc and x86-64 we now do the proper user access boilerplate. Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman