summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2012-10-19 13:37:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-19 13:37:57 -0700
commitdeb521c44fa529b24cc78a64702757a683f82487 (patch)
tree36423a9de6427ada2eb3393f1d67036902c947a1
parent17dbe27d8446232fdc7c69e9818cce5bbc6b3e31 (diff)
downloadlinux-stable-deb521c44fa529b24cc78a64702757a683f82487.tar.gz
linux-stable-deb521c44fa529b24cc78a64702757a683f82487.tar.bz2
linux-stable-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>
-rw-r--r--mm/fremap.c2
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)