From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Date: Fri, 30 Nov 2018 21:13:47 +0000 Subject: Re: [PATCHv2 net] sctp: update frag_point when stream_interleave is set Message-Id: <20181130.131347.930056639766646783.davem@davemloft.net> List-Id: References: <507afa887be8d5be9cc3030f6f21bc40719615e2.1543317110.git.lucien.xin@gmail.com> In-Reply-To: <507afa887be8d5be9cc3030f6f21bc40719615e2.1543317110.git.lucien.xin@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lucien.xin@gmail.com Cc: netdev@vger.kernel.org, linux-sctp@vger.kernel.org, marcelo.leitner@gmail.com, nhorman@tuxdriver.com, jakub.audykowicz@gmail.com From: Xin Long Date: Tue, 27 Nov 2018 19:11:50 +0800 > 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 Applied and queued up for -stable back to v4.18