From 1574639411b3ce311b846cae7fda56bf1af7d027 Mon Sep 17 00:00:00 2001 From: Colin Ian King Date: Wed, 21 Mar 2018 19:34:58 +0000 Subject: [PATCH] gre: fix TUNNEL_SEQ bit check on sequence numbering The current logic of flags | TUNNEL_SEQ is always non-zero and hence sequence numbers are always incremented no matter the setting of the TUNNEL_SEQ bit. Fix this by using & instead of |. Detected by CoverityScan, CID#1466039 ("Operands don't affect result") Fixes: 77a5196a804e ("gre: add sequence number for collect md mode.") Signed-off-by: Colin Ian King Acked-by: William Tu Signed-off-by: David S. Miller --- net/ipv4/ip_gre.c | 2 +- net/ipv6/ip6_gre.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index 2fa2ef2..9ab1aa2 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -550,7 +550,7 @@ static void gre_fb_xmit(struct sk_buff *skb, struct net_device *dev, (TUNNEL_CSUM | TUNNEL_KEY | TUNNEL_SEQ); gre_build_header(skb, tunnel_hlen, flags, proto, tunnel_id_to_key32(tun_info->key.tun_id), - (flags | TUNNEL_SEQ) ? htonl(tunnel->o_seqno++) : 0); + (flags & TUNNEL_SEQ) ? htonl(tunnel->o_seqno++) : 0); df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0; diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c index 7d8775c..6adbcf4 100644 --- a/net/ipv6/ip6_gre.c +++ b/net/ipv6/ip6_gre.c @@ -724,7 +724,7 @@ static netdev_tx_t __gre6_xmit(struct sk_buff *skb, gre_build_header(skb, tunnel->tun_hlen, flags, protocol, tunnel_id_to_key32(tun_info->key.tun_id), - (flags | TUNNEL_SEQ) ? htonl(tunnel->o_seqno++) + (flags & TUNNEL_SEQ) ? htonl(tunnel->o_seqno++) : 0); } else { -- 2.7.4