From 3f20efba41916ee17ce82f0fdd02581ada2872b2 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Wed, 27 Jan 2016 14:52:02 +0100 Subject: [PATCH] ipvs: handle ip_vs_fill_iph_skb_off failure ip_vs_fill_iph_skb_off() may not find an IP header, and gcc has determined that ip_vs_sip_fill_param() then incorrectly accesses the protocol fields: net/netfilter/ipvs/ip_vs_pe_sip.c: In function 'ip_vs_sip_fill_param': net/netfilter/ipvs/ip_vs_pe_sip.c:76:5: error: 'iph.protocol' may be used uninitialized in this function [-Werror=maybe-uninitialized] if (iph.protocol != IPPROTO_UDP) ^ net/netfilter/ipvs/ip_vs_pe_sip.c:81:10: error: 'iph.len' may be used uninitialized in this function [-Werror=maybe-uninitialized] dataoff = iph.len + sizeof(struct udphdr); ^ This adds a check for the ip_vs_fill_iph_skb_off() return code before looking at the ip header data returned from it. Signed-off-by: Arnd Bergmann Fixes: b0e010c527de ("ipvs: replace ip_vs_fill_ip4hdr with ip_vs_fill_iph_skb_off") Acked-by: Julian Anastasov Signed-off-by: Simon Horman --- net/netfilter/ipvs/ip_vs_pe_sip.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/netfilter/ipvs/ip_vs_pe_sip.c b/net/netfilter/ipvs/ip_vs_pe_sip.c index 1b8d594e493a32..c4e9ca016a88ac 100644 --- a/net/netfilter/ipvs/ip_vs_pe_sip.c +++ b/net/netfilter/ipvs/ip_vs_pe_sip.c @@ -70,10 +70,10 @@ ip_vs_sip_fill_param(struct ip_vs_conn_param *p, struct sk_buff *skb) const char *dptr; int retc; - ip_vs_fill_iph_skb(p->af, skb, false, &iph); + retc = ip_vs_fill_iph_skb(p->af, skb, false, &iph); /* Only useful with UDP */ - if (iph.protocol != IPPROTO_UDP) + if (!retc || iph.protocol != IPPROTO_UDP) return -EINVAL; /* todo: IPv6 fragments: * I think this only should be done for the first fragment. /HS