From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Fri, 18 Mar 2011 00:27:27 +0000 (+0000)
Subject: vlan: should take into account needed_headroom
X-Git-Tag: firefly_0821_release~7613^2~1737^2~93
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=d870bfb9d366c5d466c0f5419a4ec95a3f71ea8a;p=firefly-linux-kernel-4.4.55.git

vlan: should take into account needed_headroom

Commit c95b819ad7 (gre: Use needed_headroom)
made gre use needed_headroom instead of hard_header_len

This uncover a bug in vlan code.

We should make sure vlan devices take into account their
real_dev->needed_headroom or we risk a crash in ipgre_header(), because
we dont have enough room to push IP header in skb.

Reported-by: Diddi Oscarsson <diddi@diddi.se>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c
index ae610f046de5..e34ea9e5e28b 100644
--- a/net/8021q/vlan_dev.c
+++ b/net/8021q/vlan_dev.c
@@ -720,6 +720,7 @@ static int vlan_dev_init(struct net_device *dev)
 	dev->fcoe_ddp_xid = real_dev->fcoe_ddp_xid;
 #endif
 
+	dev->needed_headroom = real_dev->needed_headroom;
 	if (real_dev->features & NETIF_F_HW_VLAN_TX) {
 		dev->header_ops      = real_dev->header_ops;
 		dev->hard_header_len = real_dev->hard_header_len;