[69/80] xfs: validate acl count

Greg KH
2011-12-07T16:19:19Z

From: Christoph Hellwig <hch@infradead.org>

commit fa8b18edd752a8b4e9d1ee2cd615b82c93cf8bba upstream.

This prevents in-memory corruption and possible panics if the on-disk
ACL is badly corrupted.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
fs/xfs/linux-2.6/xfs_acl.c | 2 ++
1 file changed, 2 insertions(+)

--- a/fs/xfs/linux-2.6/xfs_acl.c
+++ b/fs/xfs/linux-2.6/xfs_acl.c
@@ -42,6 +42,8 @@ xfs_acl_from_disk(struct xfs_acl *aclp)
int count, i;

count = be32_to_cpu(aclp->acl_cnt);
+ if (count > XFS_ACL_MAX_ENTRIES)
+ return ERR_PTR(-EFSCORRUPTED);

acl = posix_acl_alloc(count, GFP_KERNEL);
if (!acl)