GFS2: Fix uninitialized VFS inode in gfs2_create_inode

When gfs2_create_inode() fails due to quota violation, the VFS
inode is not completely uninitialized. This can cause a list
corruption error.

This patch correctly uninitializes the VFS inode when a quota
violation occurs in the gfs2_create_inode codepath.

Resolves: rhbz#1059808
Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c
index a08c66e..29cacd5 100644
--- a/fs/gfs2/super.c
+++ b/fs/gfs2/super.c
@@ -1248,7 +1248,7 @@
 {
 	struct gfs2_inode *ip = GFS2_I(inode);
 
-	if (inode->i_nlink) {
+	if (!test_bit(GIF_FREE_VFS_INODE, &ip->i_flags) && inode->i_nlink) {
 		struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
 		if (gl && test_bit(GLF_DEMOTE, &gl->gl_flags))
 			clear_nlink(inode);
@@ -1463,6 +1463,11 @@
 	struct gfs2_holder gh;
 	int error;
 
+	if (test_bit(GIF_FREE_VFS_INODE, &ip->i_flags)) {
+		clear_inode(inode);
+		return;
+	}
+
 	if (inode->i_nlink || (sb->s_flags & MS_RDONLY))
 		goto out;