From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, YOSHIFUJI Hideaki , Hannes Frederic Sowa , "David S. Miller" Subject: [ 12/23] ipv6: drop packets with multiple fragmentation headers Date: Thu, 12 Sep 2013 10:45:08 -0700 Message-Id: <20130912174453.073781422@linuxfoundation.org> In-Reply-To: <20130912174451.748805761@linuxfoundation.org> References: <20130912174451.748805761@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Hannes Frederic Sowa [ Upstream commit f46078cfcd77fa5165bf849f5e568a7ac5fa569c ] It is not allowed for an ipv6 packet to contain multiple fragmentation headers. So discard packets which were already reassembled by fragmentation logic and send back a parameter problem icmp. The updates for RFC 6980 will come in later, I have to do a bit more research here. Cc: YOSHIFUJI Hideaki Signed-off-by: Hannes Frederic Sowa Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- include/linux/ipv6.h | 1 + net/ipv6/reassembly.c | 5 +++++ 2 files changed, 6 insertions(+) --- a/include/linux/ipv6.h +++ b/include/linux/ipv6.h @@ -260,6 +260,7 @@ struct inet6_skb_parm { #define IP6SKB_XFRM_TRANSFORMED 1 #define IP6SKB_FORWARDED 2 #define IP6SKB_REROUTED 4 +#define IP6SKB_FRAGMENTED 16 }; #define IP6CB(skb) ((struct inet6_skb_parm*)((skb)->cb)) --- a/net/ipv6/reassembly.c +++ b/net/ipv6/reassembly.c @@ -516,6 +516,7 @@ static int ip6_frag_reasm(struct frag_qu head->tstamp = fq->q.stamp; ipv6_hdr(head)->payload_len = htons(payload_len); IP6CB(head)->nhoff = nhoff; + IP6CB(head)->flags |= IP6SKB_FRAGMENTED; /* Yes, and fold redundant checksum back. 8) */ if (head->ip_summed == CHECKSUM_COMPLETE) @@ -551,6 +552,9 @@ static int ipv6_frag_rcv(struct sk_buff const struct ipv6hdr *hdr = ipv6_hdr(skb); struct net *net = dev_net(skb_dst(skb)->dev); + if (IP6CB(skb)->flags & IP6SKB_FRAGMENTED) + goto fail_hdr; + IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMREQDS); /* Jumbo payload inhibits frag. header */ @@ -571,6 +575,7 @@ static int ipv6_frag_rcv(struct sk_buff ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMOKS); IP6CB(skb)->nhoff = (u8 *)fhdr - skb_network_header(skb); + IP6CB(skb)->flags |= IP6SKB_FRAGMENTED; return 1; }