[PATCH 1/1] ocfs2: Fix NULL pointer dereferrence in __ocfs2_change_file_space

[Luis Henriques]

As ocfs2_fallocate() will invoke __ocfs2_change_file_space() with a NULL
as the first parameter (file), it may trigger a NULL pointer dereferrence
due to a missing check.  See http://bugs.launchpad.net/bugs/1006012.

Cc: stable at vger.kernel.org
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 fs/ocfs2/file.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 6e39668..84822a4 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1950,7 +1950,7 @@ static int __ocfs2_change_file_space(struct file *file, struct inode *inode,
 	if (ret < 0)
 		mlog_errno(ret);
 
-	if (file->f_flags & O_SYNC)
+	if (file && (file->f_flags & O_SYNC))
 		handle->h_sync = 1;
 
 	ocfs2_commit_trans(osb, handle);
-- 
1.7.9.5