diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-10-19 13:37:57 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-10-19 13:37:57 -0700 |
commit | deb521c44fa529b24cc78a64702757a683f82487 (patch) | |
tree | 36423a9de6427ada2eb3393f1d67036902c947a1 /mm | |
parent | 17dbe27d8446232fdc7c69e9818cce5bbc6b3e31 (diff) | |
download | lwn-deb521c44fa529b24cc78a64702757a683f82487.tar.gz lwn-deb521c44fa529b24cc78a64702757a683f82487.zip |
remap_file_pages: correctly handle the case of a NULL vm_ops pointer
In commit 0b173bc4daa8 ("mm: kill vma flag VM_CAN_NONLINEAR") we
replaced the VM_CAN_NONLINEAR test with checking whether the mapping has
a '->remap_pages()' vm operation, but there is no guarantee that there
it even has a vm_ops pointer at all.
Add the appropriate test for NULL vm_ops.
Reported-by: Sasha Levin <levinsasha928@gmail.com>
Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
-rw-r--r-- | mm/fremap.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/fremap.c b/mm/fremap.c index 3899a86851ce..a0aaf0e56800 100644 --- a/mm/fremap.c +++ b/mm/fremap.c @@ -169,7 +169,7 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size, if (vma->vm_private_data && !(vma->vm_flags & VM_NONLINEAR)) goto out; - if (!vma->vm_ops->remap_pages) + if (!vma->vm_ops || !vma->vm_ops->remap_pages) goto out; if (start < vma->vm_start || start + size > vma->vm_end) |