[PATCH net-next] net: Skip GSO length estimation if transport header is not set

From: Maxim Mikityanskiy <maximmi@mellanox.com>
To: "David S. Miller" <davem@davemloft.net>,
	Willem de Bruijn <willemb@google.com>,
	Saeed Mahameed <saeedm@mellanox.com>,
	Jason Wang <jasowang@redhat.com>,
	Eric Dumazet <edumazet@google.com>
Cc: "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	Eran Ben Elisha <eranbe@mellanox.com>,
	Tariq Toukan <tariqt@mellanox.com>,
	Maxim Mikityanskiy <maximmi@mellanox.com>
Subject: [PATCH net-next] net: Skip GSO length estimation if transport header is not set
Date: Fri, 22 Feb 2019 12:55:22 +0000	[thread overview]
Message-ID: <20190222125457.8509-1-maximmi@mellanox.com> (raw)
In-Reply-To: <20190221123908.7196-1-maximmi@mellanox.com>

qdisc_pkt_len_init expects transport_header to be set for GSO packets.
Patch [1] skips transport_header validation for GSO packets that don't
have network_header set at the moment of calling virtio_net_hdr_to_skb,
and allows them to pass into the stack. After patch [2] no placeholder
value is assigned to transport_header if dissection fails, so this patch
adds a check to the place where the value of transport_header is used.

[1] https://patchwork.ozlabs.org/patch/1044429/
[2] https://patchwork.ozlabs.org/patch/1046122/

Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com>
---
 net/core/dev.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/core/dev.c b/net/core/dev.c
index a3d13f5e2bfc..8a0da95ff4cc 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3421,7 +3421,7 @@ static void qdisc_pkt_len_init(struct sk_buff *skb)
 	/* To get more precise estimation of bytes sent on wire,
 	 * we add to pkt_len the headers size of all segments
 	 */
-	if (shinfo->gso_size)  {
+	if (shinfo->gso_size && skb_transport_header_was_set(skb)) {
 		unsigned int hdr_len;
 		u16 gso_segs = shinfo->gso_segs;
 
-- 
2.19.1

