diff options
| author | Duoming Zhou <duoming@zju.edu.cn> | 2024-03-12 03:59:05 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-05-30 10:49:45 +0300 |
| commit | ce47e8ead9a72834cc68431d53f8092ce69bebb7 (patch) | |
| tree | 8dc8cb1d8752e8691c142049e6ef2b33aa3c885b | |
| parent | 264dd6fe25b64e5189bd8a2151d24e205b02d927 (diff) | |
| download | linux-ce47e8ead9a72834cc68431d53f8092ce69bebb7.tar.xz | |
lib/test_hmm.c: handle src_pfns and dst_pfns allocation failure
[ Upstream commit c2af060d1c18beaec56351cf9c9bcbbc5af341a3 ]
The kcalloc() in dmirror_device_evict_chunk() will return null if the
physical memory has run out. As a result, if src_pfns or dst_pfns is
dereferenced, the null pointer dereference bug will happen.
Moreover, the device is going away. If the kcalloc() fails, the pages
mapping a chunk could not be evicted. So add a __GFP_NOFAIL flag in
kcalloc().
Finally, as there is no need to have physically contiguous memory, Switch
kcalloc() to kvcalloc() in order to avoid failing allocations.
Link: https://lkml.kernel.org/r/20240312005905.9939-1-duoming@zju.edu.cn
Fixes: b2ef9f5a5cb3 ("mm/hmm/test: add selftest driver for HMM")
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Cc: Jérôme Glisse <jglisse@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | lib/test_hmm.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/lib/test_hmm.c b/lib/test_hmm.c index 717dcb830127..b823ba7cb6a1 100644 --- a/lib/test_hmm.c +++ b/lib/test_hmm.c @@ -1226,8 +1226,8 @@ static void dmirror_device_evict_chunk(struct dmirror_chunk *chunk) unsigned long *src_pfns; unsigned long *dst_pfns; - src_pfns = kcalloc(npages, sizeof(*src_pfns), GFP_KERNEL); - dst_pfns = kcalloc(npages, sizeof(*dst_pfns), GFP_KERNEL); + src_pfns = kvcalloc(npages, sizeof(*src_pfns), GFP_KERNEL | __GFP_NOFAIL); + dst_pfns = kvcalloc(npages, sizeof(*dst_pfns), GFP_KERNEL | __GFP_NOFAIL); migrate_device_range(src_pfns, start_pfn, npages); for (i = 0; i < npages; i++) { @@ -1250,8 +1250,8 @@ static void dmirror_device_evict_chunk(struct dmirror_chunk *chunk) } migrate_device_pages(src_pfns, dst_pfns, npages); migrate_device_finalize(src_pfns, dst_pfns, npages); - kfree(src_pfns); - kfree(dst_pfns); + kvfree(src_pfns); + kvfree(dst_pfns); } /* Removes free pages from the free list so they can't be re-allocated */ |