From: Daniel Borkmann Date: Mon, 16 Sep 2013 10:36:02 +0000 (+0200) Subject: net: sctp: rfc4443: do not report ICMP redirects to user space X-Git-Tag: v3.11.5~109 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6f4a38bf6dfeda68612299aaf7cb8f0e5f7e1245;p=thirdparty%2Fkernel%2Fstable.git net: sctp: rfc4443: do not report ICMP redirects to user space [ Upstream commit 3f96a532113131d5a65ac9e00fc83cfa31b0295f ] Adapt the same behaviour for SCTP as present in TCP for ICMP redirect messages. For IPv6, RFC4443, section 2.4. says: ... (e) An ICMPv6 error message MUST NOT be originated as a result of receiving the following: ... (e.2) An ICMPv6 redirect message [IPv6-DISC]. ... Therefore, do not report an error to user space, just invoke dst's redirect callback and leave, same for IPv4 as done in TCP as well. The implication w/o having this patch could be that the reception of such packets would generate a poll notification and in worst case it could even tear down the whole connection. Therefore, stop updating sk_err on redirects. Reported-by: Duan Jiong Reported-by: Hannes Frederic Sowa Suggested-by: Vlad Yasevich Signed-off-by: Daniel Borkmann Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- diff --git a/net/sctp/input.c b/net/sctp/input.c index 3fa4d858c35a5..68155e3a6253f 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -648,8 +648,7 @@ void sctp_v4_err(struct sk_buff *skb, __u32 info) break; case ICMP_REDIRECT: sctp_icmp_redirect(sk, transport, skb); - err = 0; - break; + /* Fall through to out_unlock. */ default: goto out_unlock; } diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c index b9ff4f0f9007b..547a461eef06f 100644 --- a/net/sctp/ipv6.c +++ b/net/sctp/ipv6.c @@ -189,7 +189,7 @@ static void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, break; case NDISC_REDIRECT: sctp_icmp_redirect(sk, transport, skb); - break; + goto out_unlock; default: break; }