From f38738e2120851d8378b18a029c4b73e8516b9e0 Mon Sep 17 00:00:00 2001
From: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
Date: Fri, 5 Feb 2016 10:25:22 +0800
Subject: [PATCH] quorum: fix segfault when read fails in fifo mode

Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 block/quorum.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/block/quorum.c b/block/quorum.c
index a5ae4b8..11cc60b 100644
--- a/block/quorum.c
+++ b/block/quorum.c
@@ -286,7 +286,8 @@ static void quorum_aio_cb(void *opaque, int ret)
 
     if (acb->is_read && s->read_pattern == QUORUM_READ_PATTERN_FIFO) {
         /* We try to read next child in FIFO order if we fail to read */
-        if (ret < 0 && ++acb->child_iter < s->num_children) {
+        if (ret < 0 && (acb->child_iter + 1) < s->num_children) {
+            acb->child_iter++;
             read_fifo_child(acb);
             return;
         }
-- 
2.7.4