From c475b33242df2b2d8f6ff82c4c83f72e11a4e96d Mon Sep 17 00:00:00 2001 From: Romain KUNTZ Date: Wed, 16 Jan 2013 12:47:40 +0000 Subject: [PATCH] ipv6: fix header length calculation in ip6_append_data() [ Upstream commit 7efdba5bd9a2f3e2059beeb45c9fa55eefe1bced ] Commit 299b0767 (ipv6: Fix IPsec slowpath fragmentation problem) has introduced a error in the header length calculation that provokes corrupted packets when non-fragmentable extensions headers (Destination Option or Routing Header Type 2) are used. rt->rt6i_nfheader_len is the length of the non-fragmentable extension header, and it should be substracted to rt->dst.header_len, and not to exthdrlen, as it was done before commit 299b0767. This patch reverts to the original and correct behavior. It has been successfully tested with and without IPsec on packets that include non-fragmentable extensions headers. Signed-off-by: Romain Kuntz Acked-by: Steffen Klassert Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- net/ipv6/ip6_output.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index ae98e09ca8e7..3ccd9b226902 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -1284,10 +1284,10 @@ int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to, cork->length = 0; sk->sk_sndmsg_page = NULL; sk->sk_sndmsg_off = 0; - exthdrlen = (opt ? opt->opt_flen : 0) - rt->rt6i_nfheader_len; + exthdrlen = (opt ? opt->opt_flen : 0); length += exthdrlen; transhdrlen += exthdrlen; - dst_exthdrlen = rt->dst.header_len; + dst_exthdrlen = rt->dst.header_len - rt->rt6i_nfheader_len; } else { rt = (struct rt6_info *)cork->dst; fl6 = &inet->cork.fl.u.ip6; -- 2.39.5