[Qemu-devel] [PATCH v4 7/7] block/nbd: NBDReply is used being uninitialized

From: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
To: qemu-devel@nongnu.org, qemu-block@nongnu.org
Cc: kwolf@redhat.com, vsementsov@virtuozzo.com, mreitz@redhat.com,
	andrey.shinkevich@virtuozzo.com, den@openvz.org
Subject: [Qemu-devel] [PATCH v4 7/7] block/nbd: NBDReply is used being uninitialized
Date: Fri, 19 Jul 2019 12:40:04 +0300	[thread overview]
Message-ID: <1563529204-3368-8-git-send-email-andrey.shinkevich@virtuozzo.com> (raw)
In-Reply-To: <1563529204-3368-1-git-send-email-andrey.shinkevich@virtuozzo.com>

In case nbd_co_receive_one_chunk() fails in
nbd_reply_chunk_iter_receive(), 'NBDReply reply' parameter is used in
the check nbd_reply_is_simple() without being initialized. The iotest
083 does not pass under the Valgrind: $./check -nbd -valgrind 083.
The alternative solution is to swap the operands in the condition:
'if (s->quit || nbd_reply_is_simple(reply))'

Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
---
 block/nbd.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/block/nbd.c b/block/nbd.c
index 81edabb..8480ad4 100644
--- a/block/nbd.c
+++ b/block/nbd.c
@@ -786,7 +786,7 @@ static int nbd_co_receive_cmdread_reply(BDRVNBDState *s, uint64_t handle,
                                         int *request_ret, Error **errp)
 {
     NBDReplyChunkIter iter;
-    NBDReply reply;
+    NBDReply reply = {};
     void *payload = NULL;
     Error *local_err = NULL;
 
-- 
1.8.3.1


