The error path in prepare_write() was incorrect in the (very rare) event
that the transaction fails to start. The following prevents a NULL
pointer dereference,
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
 
        error = gfs2_trans_begin(sdp, rblocks, 0);
        if (error)
-               goto out;
+               goto out_trans_fail;
 
        if (gfs2_is_stuffed(ip)) {
                if (end > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) {
 out:
        if (error) {
                gfs2_trans_end(sdp);
+out_trans_fail:
                if (alloc_required) {
                        gfs2_inplace_release(ip);
 out_qunlock: