From: Akihiko Odaki <akihiko.odaki@daynix.com>
Date: Sat, 17 Aug 2024 07:00:43 +0000 (+0900)
Subject: net: Check if nc is NULL in qemu_get_vnet_hdr_len()
X-Git-Tag: v9.1.2~53
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=6ea3f1f06b09867615b2069edd1c45ea40474cf5;p=thirdparty%2Fqemu.git

net: Check if nc is NULL in qemu_get_vnet_hdr_len()

A netdev may not have a peer specified, resulting in NULL. We should
make it behave like /dev/null in such a case instead of letting it
cause segmentatin fault.

Fixes: 4b52d63249a5 ("tap: Remove qemu_using_vnet_hdr()")
Cc: qemu-stable@nongnu.org
Reported-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Tested-by; Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
(cherry picked from commit 76240dd2a37c7b361740616a7d6080beafdb8a71)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
---

diff --git a/net/net.c b/net/net.c
index fc1125111ca..264c4e9c5cf 100644
--- a/net/net.c
+++ b/net/net.c
@@ -542,6 +542,10 @@ void qemu_set_offload(NetClientState *nc, int csum, int tso4, int tso6,
 
 int qemu_get_vnet_hdr_len(NetClientState *nc)
 {
+    if (!nc) {
+        return 0;
+    }
+
     return nc->vnet_hdr_len;
 }