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authorAlexander Potapenko <glider@google.com>2023-04-13 15:12:20 +0200
committerAndrew Morton <akpm@linux-foundation.org>2023-04-18 14:22:13 -0700
commit47ebd0310e89c087f56e58c103c44b72a2f6b216 (patch)
tree1296475fde0380d30eb2e5d97305cfbb1d605f02 /include/linux
parenta101482421a318369eef2d0e03f2fcb40a47abad (diff)
mm: kmsan: handle alloc failures in kmsan_vmap_pages_range_noflush()
As reported by Dipanjan Das, when KMSAN is used together with kernel fault injection (or, generally, even without the latter), calls to kcalloc() or __vmap_pages_range_noflush() may fail, leaving the metadata mappings for the virtual mapping in an inconsistent state. When these metadata mappings are accessed later, the kernel crashes. To address the problem, we return a non-zero error code from kmsan_vmap_pages_range_noflush() in the case of any allocation/mapping failure inside it, and make vmap_pages_range_noflush() return an error if KMSAN fails to allocate the metadata. This patch also removes KMSAN_WARN_ON() from vmap_pages_range_noflush(), as these allocation failures are not fatal anymore. Link: https://lkml.kernel.org/r/20230413131223.4135168-1-glider@google.com Fixes: b073d7f8aee4 ("mm: kmsan: maintain KMSAN metadata for page operations") Signed-off-by: Alexander Potapenko <glider@google.com> Reported-by: Dipanjan Das <mail.dipanjan.das@gmail.com> Link: https://lore.kernel.org/linux-mm/CANX2M5ZRrRA64k0hOif02TjmY9kbbO2aCBPyq79es34RXZ=cAw@mail.gmail.com/ Reviewed-by: Marco Elver <elver@google.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Uladzislau Rezki (Sony) <urezki@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'include/linux')
-rw-r--r--include/linux/kmsan.h20
1 files changed, 11 insertions, 9 deletions
diff --git a/include/linux/kmsan.h b/include/linux/kmsan.h
index e38ae3c34618..c7ff3aefc5a1 100644
--- a/include/linux/kmsan.h
+++ b/include/linux/kmsan.h
@@ -134,11 +134,12 @@ void kmsan_kfree_large(const void *ptr);
* @page_shift: page_shift passed to vmap_range_noflush().
*
* KMSAN maps shadow and origin pages of @pages into contiguous ranges in
- * vmalloc metadata address range.
+ * vmalloc metadata address range. Returns 0 on success, callers must check
+ * for non-zero return value.
*/
-void kmsan_vmap_pages_range_noflush(unsigned long start, unsigned long end,
- pgprot_t prot, struct page **pages,
- unsigned int page_shift);
+int kmsan_vmap_pages_range_noflush(unsigned long start, unsigned long end,
+ pgprot_t prot, struct page **pages,
+ unsigned int page_shift);
/**
* kmsan_vunmap_kernel_range_noflush() - Notify KMSAN about a vunmap.
@@ -281,12 +282,13 @@ static inline void kmsan_kfree_large(const void *ptr)
{
}
-static inline void kmsan_vmap_pages_range_noflush(unsigned long start,
- unsigned long end,
- pgprot_t prot,
- struct page **pages,
- unsigned int page_shift)
+static inline int kmsan_vmap_pages_range_noflush(unsigned long start,
+ unsigned long end,
+ pgprot_t prot,
+ struct page **pages,
+ unsigned int page_shift)
{
+ return 0;
}
static inline void kmsan_vunmap_range_noflush(unsigned long start,