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| author | Joao Martins <joao.m.martins@oracle.com> | 2021-07-14 21:27:11 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-07-15 10:13:49 -0700 |
| commit | d08af0a59684e18a51aa4bfd24c658994ea3fc5b (patch) | |
| tree | 20183f284e5c2d7f150ed5d359699491ad221af4 /fs | |
| parent | b3b2177a2d795e35dc11597b2609eb1e7e57e570 (diff) | |
| download | linux-d08af0a59684e18a51aa4bfd24c658994ea3fc5b.tar.bz2 | |
mm/hugetlb: fix refs calculation from unaligned @vaddr
Commit 82e5d378b0e47 ("mm/hugetlb: refactor subpage recording")
refactored the count of subpages but missed an edge case when @vaddr is
not aligned to PAGE_SIZE e.g. when close to vma->vm_end. It would then
errousnly set @refs to 0 and record_subpages_vmas() wouldn't set the
@pages array element to its value, consequently causing the reported
null-deref by syzbot.
Fix it by aligning down @vaddr by PAGE_SIZE in @refs calculation.
Link: https://lkml.kernel.org/r/20210713152440.28650-1-joao.m.martins@oracle.com
Fixes: 82e5d378b0e47 ("mm/hugetlb: refactor subpage recording")
Reported-by: syzbot+a3fcd59df1b372066f5a@syzkaller.appspotmail.com
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs')
0 files changed, 0 insertions, 0 deletions