From 4135cce7fd0a0d755665c02728578c7c5afe4726 Mon Sep 17 00:00:00 2001 From: Xin Long Date: Tue, 27 Nov 2018 19:11:50 +0800 Subject: [PATCH] sctp: update frag_point when stream_interleave is set sctp_assoc_update_frag_point() should be called whenever asoc->pathmtu changes, but we missed one place in sctp_association_init(). It would cause frag_point is zero when sending data. As says in Jakub's reproducer, if sp->pathmtu is set by socketopt, the new asoc->pathmtu inherits it in sctp_association_init(). Later when transports are added and their pmtu >= asoc->pathmtu, it will never call sctp_assoc_update_frag_point() to set frag_point. This patch is to fix it by updating frag_point after asoc->pathmtu is set as sp->pathmtu in sctp_association_init(). Note that it moved them after sctp_stream_init(), as stream->si needs to be set first. Frag_point's calculation is also related with datachunk's type, so it needs to update frag_point when stream->si may be changed in sctp_process_init(). v1->v2: - call sctp_assoc_update_frag_point() separately in sctp_process_init and sctp_association_init, per Marcelo's suggestion. Fixes: 2f5e3c9df693 ("sctp: introduce sctp_assoc_update_frag_point") Reported-by: Jakub Audykowicz Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Acked-by: Neil Horman Signed-off-by: David S. Miller --- net/sctp/associola.c | 7 ++++--- net/sctp/sm_make_chunk.c | 3 +++ 2 files changed, 7 insertions(+), 3 deletions(-) diff --git a/net/sctp/associola.c b/net/sctp/associola.c index 6a28b96e779e..dd77ec3892b6 100644 --- a/net/sctp/associola.c +++ b/net/sctp/associola.c @@ -118,9 +118,6 @@ static struct sctp_association *sctp_association_init( asoc->flowlabel = sp->flowlabel; asoc->dscp = sp->dscp; - /* Initialize default path MTU. */ - asoc->pathmtu = sp->pathmtu; - /* Set association default SACK delay */ asoc->sackdelay = msecs_to_jiffies(sp->sackdelay); asoc->sackfreq = sp->sackfreq; @@ -252,6 +249,10 @@ static struct sctp_association *sctp_association_init( 0, gfp)) goto fail_init; + /* Initialize default path MTU. */ + asoc->pathmtu = sp->pathmtu; + sctp_assoc_update_frag_point(asoc); + /* Assume that peer would support both address types unless we are * told otherwise. */ diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c index 4a4fd1971255..f4ac6c592e13 100644 --- a/net/sctp/sm_make_chunk.c +++ b/net/sctp/sm_make_chunk.c @@ -2462,6 +2462,9 @@ int sctp_process_init(struct sctp_association *asoc, struct sctp_chunk *chunk, asoc->c.sinit_max_instreams, gfp)) goto clean_up; + /* Update frag_point when stream_interleave may get changed. */ + sctp_assoc_update_frag_point(asoc); + if (!asoc->temp && sctp_assoc_set_id(asoc, gfp)) goto clean_up; -- 2.30.2