From 61e7f09d0f437c9614029445754099383ec2eec4 Mon Sep 17 00:00:00 2001 From: Hannes Frederic Sowa Date: Thu, 19 Dec 2013 02:13:36 +0100 Subject: [PATCH] ipv4: consistent reporting of pmtu data in case of corking We report different pmtu values back on the first write and on further writes on an corked socket. Also don't include the dst.header_len (respectively exthdrlen) as this should already be dealt with by the interface mtu of the outgoing (virtual) interface and policy of that interface should dictate if fragmentation should happen. Instead reduce the pmtu data by IP options as we do for IPv6. Make the same changes for ip_append_data, where we did not care about options or dst.header_len at all. Signed-off-by: Hannes Frederic Sowa Signed-off-by: David S. Miller --- net/ipv4/ip_output.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index 912402752f2f..df184616493f 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -828,7 +828,7 @@ static int __ip_append_data(struct sock *sk, if (cork->length + length > maxnonfragsize - fragheaderlen) { ip_local_error(sk, EMSGSIZE, fl4->daddr, inet->inet_dport, - mtu-exthdrlen); + mtu - (opt ? opt->optlen : 0)); return -EMSGSIZE; } @@ -1151,7 +1151,8 @@ ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page, mtu : 0xFFFF; if (cork->length + size > maxnonfragsize - fragheaderlen) { - ip_local_error(sk, EMSGSIZE, fl4->daddr, inet->inet_dport, mtu); + ip_local_error(sk, EMSGSIZE, fl4->daddr, inet->inet_dport, + mtu - (opt ? opt->optlen : 0)); return -EMSGSIZE; } -- 2.45.2