From 37f47bc90c7481e7959703ad1defc4fc9f5d85e3 Mon Sep 17 00:00:00 2001 From: Marcelo Ricardo Leitner Date: Thu, 11 Jan 2018 14:22:06 -0200 Subject: sctp: avoid compiler warning on implicit fallthru These fall-through are expected. Signed-off-by: Marcelo Ricardo Leitner Acked-by: Neil Horman Reviewed-by: Xin Long Signed-off-by: David S. Miller --- net/sctp/ipv6.c | 1 + net/sctp/outqueue.c | 4 ++-- 2 files changed, 3 insertions(+), 2 deletions(-) (limited to 'net/sctp') diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c index 3b18085e3b10..5d4c15bf66d2 100644 --- a/net/sctp/ipv6.c +++ b/net/sctp/ipv6.c @@ -826,6 +826,7 @@ static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp) case AF_INET: if (!__ipv6_only_sock(sctp_opt2sk(sp))) return 1; + /* fallthru */ default: return 0; } diff --git a/net/sctp/outqueue.c b/net/sctp/outqueue.c index 7d67feeeffc1..c4ec99b20150 100644 --- a/net/sctp/outqueue.c +++ b/net/sctp/outqueue.c @@ -918,9 +918,9 @@ static void sctp_outq_flush(struct sctp_outq *q, int rtx_timeout, gfp_t gfp) break; case SCTP_CID_ABORT: - if (sctp_test_T_bit(chunk)) { + if (sctp_test_T_bit(chunk)) packet->vtag = asoc->c.my_vtag; - } + /* fallthru */ /* The following chunks are "response" chunks, i.e. * they are generated in response to something we * received. If we are sending these, then we can -- cgit v1.2.3 From 625637bf4afa45204bd87e4218645182a919485a Mon Sep 17 00:00:00 2001 From: Xin Long Date: Mon, 15 Jan 2018 17:01:19 +0800 Subject: sctp: reinit stream if stream outcnt has been change by sinit in sendmsg After introducing sctp_stream structure, sctp uses stream->outcnt as the out stream nums instead of c.sinit_num_ostreams. However when users use sinit in cmsg, it only updates c.sinit_num_ostreams in sctp_sendmsg. At that moment, stream->outcnt is still using previous value. If it's value is not updated, the sinit_num_ostreams of sinit could not really work. This patch is to fix it by updating stream->outcnt and reiniting stream if stream outcnt has been change by sinit in sendmsg. Fixes: a83863174a61 ("sctp: prepare asoc stream for stream reconf") Signed-off-by: Xin Long Acked-by: Neil Horman Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller --- net/sctp/socket.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'net/sctp') diff --git a/net/sctp/socket.c b/net/sctp/socket.c index 9b01e994f661..15ae018b386f 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -1883,8 +1883,14 @@ static int sctp_sendmsg(struct sock *sk, struct msghdr *msg, size_t msg_len) */ if (sinit) { if (sinit->sinit_num_ostreams) { - asoc->c.sinit_num_ostreams = - sinit->sinit_num_ostreams; + __u16 outcnt = sinit->sinit_num_ostreams; + + asoc->c.sinit_num_ostreams = outcnt; + /* outcnt has been changed, so re-init stream */ + err = sctp_stream_init(&asoc->stream, outcnt, 0, + GFP_KERNEL); + if (err) + goto out_free; } if (sinit->sinit_max_instreams) { asoc->c.sinit_max_instreams = -- cgit v1.2.3 From a0ff660058b88d12625a783ce9e5c1371c87951f Mon Sep 17 00:00:00 2001 From: Xin Long Date: Mon, 15 Jan 2018 17:01:36 +0800 Subject: sctp: return error if the asoc has been peeled off in sctp_wait_for_sndbuf After commit cea0cc80a677 ("sctp: use the right sk after waking up from wait_buf sleep"), it may change to lock another sk if the asoc has been peeled off in sctp_wait_for_sndbuf. However, the asoc's new sk could be already closed elsewhere, as it's in the sendmsg context of the old sk that can't avoid the new sk's closing. If the sk's last one refcnt is held by this asoc, later on after putting this asoc, the new sk will be freed, while under it's own lock. This patch is to revert that commit, but fix the old issue by returning error under the old sk's lock. Fixes: cea0cc80a677 ("sctp: use the right sk after waking up from wait_buf sleep") Reported-by: syzbot+ac6ea7baa4432811eb50@syzkaller.appspotmail.com Signed-off-by: Xin Long Acked-by: Neil Horman Signed-off-by: David S. Miller --- net/sctp/socket.c | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-) (limited to 'net/sctp') diff --git a/net/sctp/socket.c b/net/sctp/socket.c index 15ae018b386f..feb2ca69827a 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -85,7 +85,7 @@ static int sctp_writeable(struct sock *sk); static void sctp_wfree(struct sk_buff *skb); static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p, - size_t msg_len, struct sock **orig_sk); + size_t msg_len); static int sctp_wait_for_packet(struct sock *sk, int *err, long *timeo_p); static int sctp_wait_for_connect(struct sctp_association *, long *timeo_p); static int sctp_wait_for_accept(struct sock *sk, long timeo); @@ -1977,7 +1977,7 @@ static int sctp_sendmsg(struct sock *sk, struct msghdr *msg, size_t msg_len) timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); if (!sctp_wspace(asoc)) { /* sk can be changed by peel off when waiting for buf. */ - err = sctp_wait_for_sndbuf(asoc, &timeo, msg_len, &sk); + err = sctp_wait_for_sndbuf(asoc, &timeo, msg_len); if (err) { if (err == -ESRCH) { /* asoc is already dead. */ @@ -8022,12 +8022,12 @@ void sctp_sock_rfree(struct sk_buff *skb) /* Helper function to wait for space in the sndbuf. */ static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p, - size_t msg_len, struct sock **orig_sk) + size_t msg_len) { struct sock *sk = asoc->base.sk; - int err = 0; long current_timeo = *timeo_p; DEFINE_WAIT(wait); + int err = 0; pr_debug("%s: asoc:%p, timeo:%ld, msg_len:%zu\n", __func__, asoc, *timeo_p, msg_len); @@ -8056,17 +8056,13 @@ static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p, release_sock(sk); current_timeo = schedule_timeout(current_timeo); lock_sock(sk); - if (sk != asoc->base.sk) { - release_sock(sk); - sk = asoc->base.sk; - lock_sock(sk); - } + if (sk != asoc->base.sk) + goto do_error; *timeo_p = current_timeo; } out: - *orig_sk = sk; finish_wait(&asoc->wait, &wait); /* Release the association's refcnt. */ -- cgit v1.2.3 From c5006b8aa74599ce19104b31d322d2ea9ff887cc Mon Sep 17 00:00:00 2001 From: Xin Long Date: Mon, 15 Jan 2018 17:02:00 +0800 Subject: sctp: do not allow the v4 socket to bind a v4mapped v6 address The check in sctp_sockaddr_af is not robust enough to forbid binding a v4mapped v6 addr on a v4 socket. The worse thing is that v4 socket's bind_verify would not convert this v4mapped v6 addr to a v4 addr. syzbot even reported a crash as the v4 socket bound a v6 addr. This patch is to fix it by doing the common sa.sa_family check first, then AF_INET check for v4mapped v6 addrs. Fixes: 7dab83de50c7 ("sctp: Support ipv6only AF_INET6 sockets.") Reported-by: syzbot+7b7b518b1228d2743963@syzkaller.appspotmail.com Acked-by: Neil Horman Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller --- net/sctp/socket.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) (limited to 'net/sctp') diff --git a/net/sctp/socket.c b/net/sctp/socket.c index feb2ca69827a..039fcb618c34 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -335,16 +335,14 @@ static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt, if (len < sizeof (struct sockaddr)) return NULL; + if (!opt->pf->af_supported(addr->sa.sa_family, opt)) + return NULL; + /* V4 mapped address are really of AF_INET family */ if (addr->sa.sa_family == AF_INET6 && - ipv6_addr_v4mapped(&addr->v6.sin6_addr)) { - if (!opt->pf->af_supported(AF_INET, opt)) - return NULL; - } else { - /* Does this PF support this AF? */ - if (!opt->pf->af_supported(addr->sa.sa_family, opt)) - return NULL; - } + ipv6_addr_v4mapped(&addr->v6.sin6_addr) && + !opt->pf->af_supported(AF_INET, opt)) + return NULL; /* If we get this far, af is valid. */ af = sctp_get_af_specific(addr->sa.sa_family); -- cgit v1.2.3