diff options
| author | Pratyush Yadav <pratyush@kernel.org> | 2025-11-03 12:01:57 +0100 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-11-09 21:19:47 -0800 |
| commit | 0b07092d09e54e49b85379a9c60f82d54a881514 (patch) | |
| tree | aeddb3ce6b525bbef845eac7da9cf90abb19b4a5 | |
| parent | bba717bbc466ab24d25964034f5e16ead1720512 (diff) | |
kho: fix out-of-bounds access of vmalloc chunk
The list of pages in a vmalloc chunk is NULL-terminated. So when looping
through the pages in a vmalloc chunk, both kho_restore_vmalloc() and
kho_vmalloc_unpreserve_chunk() rightly make sure to stop when encountering
a NULL page. But when the chunk is full, the loops do not stop and go
past the bounds of chunk->phys, resulting in out-of-bounds memory access,
and possibly the restoration or unpreservation of an invalid page.
Fix this by making sure the processing of chunk stops at the end of the
array.
Link: https://lkml.kernel.org/r/20251103110159.8399-1-pratyush@kernel.org
Fixes: a667300bd53f ("kho: add support for preserving vmalloc allocations")
Signed-off-by: Pratyush Yadav <pratyush@kernel.org>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Alexander Graf <graf@amazon.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | kernel/kexec_handover.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/kexec_handover.c b/kernel/kexec_handover.c index 2a8c20c238a8..36fdce2667c5 100644 --- a/kernel/kexec_handover.c +++ b/kernel/kexec_handover.c @@ -889,7 +889,7 @@ static void kho_vmalloc_unpreserve_chunk(struct kho_vmalloc_chunk *chunk) __kho_unpreserve(track, pfn, pfn + 1); - for (int i = 0; chunk->phys[i]; i++) { + for (int i = 0; i < ARRAY_SIZE(chunk->phys) && chunk->phys[i]; i++) { pfn = PHYS_PFN(chunk->phys[i]); __kho_unpreserve(track, pfn, pfn + 1); } @@ -1012,7 +1012,7 @@ void *kho_restore_vmalloc(const struct kho_vmalloc *preservation) while (chunk) { struct page *page; - for (int i = 0; chunk->phys[i]; i++) { + for (int i = 0; i < ARRAY_SIZE(chunk->phys) && chunk->phys[i]; i++) { phys_addr_t phys = chunk->phys[i]; if (idx + contig_pages > total_pages) |