kernel/linux.git/lib, branch v7.0.13

debugobjects: Don't call fill_pool() in early boot hardirq context

2026-06-19T11:48:12+00:00

commit 0d046ae106255cba5eb83b23f78ee93f3620247d upstream. When booting a debug PREEMPT_RT kernel on an ARM64 system, a "inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage" lockdep warning message was reported to the console. During early boot, interrupts are enabled before the scheduler is enabled. In this window (before SYSTEM_SCHEDULING is set) interrupts can fire and in the hard interrupt context handler attempt to fill the pool This can lead to a deadlock when the interrupt occurred when the interrupt hits a region which holds a lock that is required to be taken in the allocation path. Add a new can_fill_pool() helper and reorder the exception rule and forbid this scenario by excluding allocations from hard interrupt context. Fixes: 06e0ae988f6e ("debugobjects: Allow to refill the pool before SYSTEM_SCHEDULING") Suggested-by: Sebastian Andrzej Siewior Suggested-by: Thomas Gleixner Signed-off-by: Waiman Long Signed-off-by: Thomas Gleixner Reviewed-by: Sebastian Andrzej Siewior Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260605173038.495075-1-longman@redhat.com Signed-off-by: Greg Kroah-Hartman

debugobjects: Do not fill_pool() if pi_blocked_on

2026-06-19T11:48:12+00:00

commit 5f41161059fd0f1bbf18c90f3180e38cc45a14eb upstream. On RT enabled kernels, fill_pool() ends up calling rtlock_lock(), which asserts if current::pi_blocked_on is set, because a task can obviously only block on one lock as otherwise the priority inheritenace chain gets corrupted. Prevent this by expanding the conditional to take current::pi_blocked_on into account. Fixes: 4bedcc28469a ("debugobjects: Make them PREEMPT_RT aware") Reported-by: syzbot+b8ca586b9fc235f0c0df@syzkaller.appspotmail.com Signed-off-by: Helen Koike Signed-off-by: Thomas Gleixner Link: https://patch.msgid.link/20260511215359.3351259-1-koike@igalia.com Closes: https://syzkaller.appspot.com/bug?extid=b8ca586b9fc235f0c0df Signed-off-by: Greg Kroah-Hartman

iommu, debugobjects: avoid gcc-16.1 section mismatch warnings

2026-06-09T10:32:39+00:00

commit 4c9ad387aa2d6785299722e54224d34764edaeb3 upstream. gcc-16 has gained some more advanced inter-procedual optimization techniques that enable it to inline the dummy_tlb_add_page() and dummy_tlb_flush() function pointers into a specialized version of __arm_v7s_unmap: WARNING: modpost: vmlinux: section mismatch in reference: __arm_v7s_unmap+0x2cc (section: .text) -> dummy_tlb_add_page (section: .init.text) ERROR: modpost: Section mismatches detected. >From what I can tell, the transformation is correct, as this is only called when __arm_v7s_unmap() is called from arm_v7s_do_selftests(), which is also __init. Since __arm_v7s_unmap() however is not __init, gcc cannot inline the inner function calls directly. In debug_objects_selftest(), the same thing happens. Both the caller and the leaf function are __init, but the IPA pulls it into a non-init one: WARNING: modpost: vmlinux: section mismatch in reference: lookup_object_or_alloc+0x7c (section: .text.lookup_object_or_alloc) -> is_static_object (section: .init.text) Marking the affected functions as not "__init" would reliably avoid this issue but is not a good solution because it removes an otherwise correct annotation. I tried marking the functions as 'noinline', but that ended up not covering all the affected configurations. With some more experimenting, I found that marking these functions as __attribute__((noipa)) is both logical and reliable. In order to keep the syntax readable, add a custom macro for this in include/linux/compiler_attributes.h next to other related macros and use it to annotate both files. Link: https://lore.kernel.org/all/abRB6g-48ZX6Yl2r@willie-the-truck/ Cc: Will Deacon Cc: Thomas Gleixner Cc: Andrew Morton Cc: Miguel Ojeda Cc: linux-kbuild@vger.kernel.org Cc: stable@vger.kernel.org Signed-off-by: Arnd Bergmann Acked-by: Will Deacon Acked-by: Thomas Gleixner Acked-by: Miguel Ojeda Signed-off-by: Joerg Roedel Signed-off-by: Greg Kroah-Hartman

kunit: fix use-after-free in debugfs when using kunit.filter

2026-06-09T10:32:21+00:00

[ Upstream commit fb6988b83b4cafe8db63999c1ddff1b7c66d2ff5 ] When the kernel is booted with a kunit filter (e.g., kunit.filter="speed!=slow"), the kunit executor dynamically allocates copies of the filtered test suites using kmalloc/kmemdup. During the initial boot execution, kunit_debugfs_create_suite() creates debugfs files (such as /sys/kernel/debug/kunit//run) and permanently stores a pointer to the dynamically allocated suite in the inode's i_private field. Previously, the executor freed this dynamically allocated suite_set immediately after executing the boot-time tests. Because the debugfs nodes were not destroyed, any subsequent interaction with the debugfs `run` file from userspace triggered a use-after-free (UAF). On systems with architectural capabilities, like CHERI RISC-V, this resulted in an immediate fatal hardware exception due to the invalidation of the capability tags on the reclaimed memory. On other architectures, it resulted in silent memory corruption. Fix this UAF by properly coupling the lifetime of the filtered suite memory allocation to the lifetime of the kunit subsystem and its associated VFS nodes. Ownership of the boot-time suite_set is now transferred to a global tracker ('kunit_boot_suites'), and the memory is cleanly released in kunit_exit() during module teardown. Link: https://lore.kernel.org/r/20260507084854.233984-1-florian.schmaus@codasip.com Fixes: e2219db280e3 ("kunit: add debugfs /sys/kernel/debug/kunit//results display") Signed-off-by: Florian Schmaus Reviewed-by: Martin Kaiser Reviewed-by: David Gow Signed-off-by: Shuah Khan Signed-off-by: Sasha Levin

test_kprobes: clear kprobes between test runs

2026-06-01T15:54:36+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

2026-06-01T15:54:34+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

2026-06-01T15:54:34+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

lib: kunit_iov_iter: fix memory leaks

2026-05-23T11:09:04+00:00

[ Upstream commit 0b49c7d0ae697fcecd7377cb7dda220f7cd096ff ] Use vfree() instead of vunmap() to free the buffer allocated by iov_kunit_create_buffer() because vunmap() does not honour VM_MAP_PUT_PAGES. In order for this to work the page array itself must not be managed by kunit. Remove the folio_put() when destroying a folioq. This is handled by vfree(), now. Pointed out by sashiko.dev on a previous iteration of this series. Tested by running the kunit test 10000 times in a loop. Link: https://lkml.kernel.org/r/20260326214905.818170-4-lk@c--e.de Fixes: 2d71340ff1d4 ("iov_iter: Kunit tests for copying to/from an iterator") Signed-off-by: Christian A. Ehrhardt Cc: David Howells Cc: David Gow Cc: Kees Cook Cc: Petr Mladek Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin

lib/scatterlist: fix temp buffer in extract_user_to_sg()

2026-05-14T13:31:13+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

2026-05-14T13:31:13+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