e4943fb024
JIRA: https://issues.redhat.com/browse/RHEL-78704 Upstream Status: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git commit 7591c127f3b17d5879f18819cad7058bf3a2e276 Author: Catalin Marinas <catalin.marinas@arm.com> Date: Mon Nov 4 11:19:44 2024 +0000 kmemleak: iommu/iova: fix transient kmemleak false positive The introduction of iova_depot_pop() in 911aa1245da8 ("iommu/iova: Make the rcache depot scale better") confused kmemleak by moving a struct iova_magazine object from a singly linked list to rcache->depot and resetting the 'next' pointer referencing it. Unlike doubly linked lists, the content of the object being referred is never changed on removal from a singly linked list and the kmemleak checksum heuristics do not detect such scenario. This leads to false positives like: unreferenced object 0xffff8881a5301000 (size 1024): comm "softirq", pid 0, jiffies 4306297099 (age 462.991s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 e7 7d 05 00 00 00 00 00 .........}...... 0f b4 05 00 00 00 00 00 b4 96 05 00 00 00 00 00 ................ backtrace: [<ffffffff819f5f08>] __kmem_cache_alloc_node+0x1e8/0x320 [<ffffffff818a239a>] kmalloc_trace+0x2a/0x60 [<ffffffff8231d31e>] free_iova_fast+0x28e/0x4e0 [<ffffffff82310860>] fq_ring_free_locked+0x1b0/0x310 [<ffffffff8231225d>] fq_flush_timeout+0x19d/0x2e0 [<ffffffff813e95ba>] call_timer_fn+0x19a/0x5c0 [<ffffffff813ea16b>] __run_timers+0x78b/0xb80 [<ffffffff813ea5bd>] run_timer_softirq+0x5d/0xd0 [<ffffffff82f1d915>] __do_softirq+0x205/0x8b5 Introduce kmemleak_transient_leak() which resets the object checksum requiring another scan pass before it is reported (if still unreferenced). Call this new API in iova_depot_pop(). Link: https://lkml.kernel.org/r/20241104111944.2207155-1-catalin.marinas@arm.com Link: https://lore.kernel.org/r/ZY1osaGLyT-sdKE8@shredder/ Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Ido Schimmel <idosch@idosch.org> Tested-by: Ido Schimmel <idosch@nvidia.com> Acked-by: Robin Murphy <robin.murphy@arm.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> (cherry picked from commit 7591c127f3b17d5879f18819cad7058bf3a2e276) Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com> |
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| .. | ||
| kunit | ||
| checkpatch.rst | ||
| coccinelle.rst | ||
| gcov.rst | ||
| gdb-kernel-debugging.rst | ||
| index.rst | ||
| kasan.rst | ||
| kcov.rst | ||
| kcsan.rst | ||
| kfence.rst | ||
| kgdb.rst | ||
| kmemleak.rst | ||
| kmsan.rst | ||
| kselftest.rst | ||
| sparse.rst | ||
| testing-overview.rst | ||
| ubsan.rst | ||