From 91705c61b52029ab5da67a15a23eef08667bf40e Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Tue, 23 Jul 2013 14:51:47 +0200 Subject: net: sctp: trivial: update mailing list address The SCTP mailing list address to send patches or questions to is linux-sctp@vger.kernel.org and not lksctp-developers@lists.sourceforge.net anymore. Therefore, update all occurences. Signed-off-by: Daniel Borkmann Acked-by: Neil Horman Acked-by: Vlad Yasevich Signed-off-by: David S. Miller --- net/sctp/chunk.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/sctp/chunk.c') diff --git a/net/sctp/chunk.c b/net/sctp/chunk.c index 5780565f5b7d..b50b90c16a86 100644 --- a/net/sctp/chunk.c +++ b/net/sctp/chunk.c @@ -24,7 +24,7 @@ * * Please send any bug reports or fixes you make to the * email address(es): - * lksctp developers + * lksctp developers * * Or submit a bug report through the following website: * http://www.sf.net/projects/lksctp -- cgit v1.2.3 From 477143e3fece3dc12629bb1ebd7b47e8e6e72b2b Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Tue, 6 Aug 2013 21:18:13 +0200 Subject: net: sctp: trivial: update bug report in header comment With the restructuring of the lksctp.org site, we only allow bug reports through the SCTP mailing list linux-sctp@vger.kernel.org, not via SF, as SF is only used for web hosting and nothing more. While at it, also remove the obvious statement that bugs will be fixed and incooperated into the kernel. Signed-off-by: Daniel Borkmann Acked-by: Vlad Yasevich Signed-off-by: David S. Miller --- net/sctp/chunk.c | 6 ------ 1 file changed, 6 deletions(-) (limited to 'net/sctp/chunk.c') diff --git a/net/sctp/chunk.c b/net/sctp/chunk.c index b50b90c16a86..bd0bdd0ba8f1 100644 --- a/net/sctp/chunk.c +++ b/net/sctp/chunk.c @@ -26,15 +26,9 @@ * email address(es): * lksctp developers * - * Or submit a bug report through the following website: - * http://www.sf.net/projects/lksctp - * * Written or modified by: * Jon Grimm * Sridhar Samudrala - * - * Any bugs reported given to us we will try to fix... any fixes shared will - * be incorporated into the next SCTP release. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt -- cgit v1.2.3 From c08751c851b78514f6ec5f77f7cbebaac63d15c0 Mon Sep 17 00:00:00 2001 From: Alexander Sverdlin Date: Mon, 2 Sep 2013 15:58:25 +0200 Subject: net: sctp: Fix data chunk fragmentation for MTU values which are not multiple of 4 net: sctp: Fix data chunk fragmentation for MTU values which are not multiple of 4 Initially the problem was observed with ipsec, but later it became clear that SCTP data chunk fragmentation algorithm has problems with MTU values which are not multiple of 4. Test program was used which just transmits 2000 bytes long packets to other host. tcpdump was used to observe re-fragmentation in IP layer after SCTP already fragmented data chunks. With MTU 1500: 12:54:34.082904 IP (tos 0x2,ECT(0), ttl 64, id 0, offset 0, flags [DF], proto SCTP (132), length 1500) 10.151.38.153.39303 > 10.151.24.91.54321: sctp (1) [DATA] (B) [TSN: 2366088589] [SID: 0] [SSEQ 1] [PPID 0x0] 12:54:34.082933 IP (tos 0x2,ECT(0), ttl 64, id 0, offset 0, flags [DF], proto SCTP (132), length 596) 10.151.38.153.39303 > 10.151.24.91.54321: sctp (1) [DATA] (E) [TSN: 2366088590] [SID: 0] [SSEQ 1] [PPID 0x0] 12:54:34.090576 IP (tos 0x2,ECT(0), ttl 63, id 0, offset 0, flags [DF], proto SCTP (132), length 48) 10.151.24.91.54321 > 10.151.38.153.39303: sctp (1) [SACK] [cum ack 2366088590] [a_rwnd 79920] [#gap acks 0] [#dup tsns 0] With MTU 1499: 13:02:49.955220 IP (tos 0x2,ECT(0), ttl 64, id 48215, offset 0, flags [+], proto SCTP (132), length 1492) 10.151.38.153.39084 > 10.151.24.91.54321: sctp[|sctp] 13:02:49.955249 IP (tos 0x2,ECT(0), ttl 64, id 48215, offset 1472, flags [none], proto SCTP (132), length 28) 10.151.38.153 > 10.151.24.91: ip-proto-132 13:02:49.955262 IP (tos 0x2,ECT(0), ttl 64, id 0, offset 0, flags [DF], proto SCTP (132), length 600) 10.151.38.153.39084 > 10.151.24.91.54321: sctp (1) [DATA] (E) [TSN: 404355346] [SID: 0] [SSEQ 1] [PPID 0x0] 13:02:49.956770 IP (tos 0x2,ECT(0), ttl 63, id 0, offset 0, flags [DF], proto SCTP (132), length 48) 10.151.24.91.54321 > 10.151.38.153.39084: sctp (1) [SACK] [cum ack 404355346] [a_rwnd 79920] [#gap acks 0] [#dup tsns 0] Here problem in data portion limit calculation leads to re-fragmentation in IP, which is sub-optimal. The problem is max_data initial value, which doesn't take into account the fact, that data chunk must be padded to 4-bytes boundary. It's enough to correct max_data, because all later adjustments are correctly aligned to 4-bytes boundary. After the fix is applied, everything is fragmented correctly for uneven MTUs: 15:16:27.083881 IP (tos 0x2,ECT(0), ttl 64, id 0, offset 0, flags [DF], proto SCTP (132), length 1496) 10.151.38.153.53417 > 10.151.24.91.54321: sctp (1) [DATA] (B) [TSN: 3077098183] [SID: 0] [SSEQ 1] [PPID 0x0] 15:16:27.083907 IP (tos 0x2,ECT(0), ttl 64, id 0, offset 0, flags [DF], proto SCTP (132), length 600) 10.151.38.153.53417 > 10.151.24.91.54321: sctp (1) [DATA] (E) [TSN: 3077098184] [SID: 0] [SSEQ 1] [PPID 0x0] 15:16:27.085640 IP (tos 0x2,ECT(0), ttl 63, id 0, offset 0, flags [DF], proto SCTP (132), length 48) 10.151.24.91.54321 > 10.151.38.153.53417: sctp (1) [SACK] [cum ack 3077098184] [a_rwnd 79920] [#gap acks 0] [#dup tsns 0] The bug was there for years already, but - is a performance issue, the packets are still transmitted - doesn't show up with default MTU 1500, but possibly with ipsec (MTU 1438) Signed-off-by: Alexander Sverdlin Acked-by: Vlad Yasevich Acked-by: Neil Horman Signed-off-by: David S. Miller --- net/sctp/chunk.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net/sctp/chunk.c') diff --git a/net/sctp/chunk.c b/net/sctp/chunk.c index bd0bdd0ba8f1..7bd5ed4a8657 100644 --- a/net/sctp/chunk.c +++ b/net/sctp/chunk.c @@ -195,9 +195,9 @@ struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *asoc, /* This is the biggest possible DATA chunk that can fit into * the packet */ - max_data = asoc->pathmtu - + max_data = (asoc->pathmtu - sctp_sk(asoc->base.sk)->pf->af->net_header_len - - sizeof(struct sctphdr) - sizeof(struct sctp_data_chunk); + sizeof(struct sctphdr) - sizeof(struct sctp_data_chunk)) & ~3; max = asoc->frag_point; /* If the the peer requested that we authenticate DATA chunks -- cgit v1.2.3