From df132eff463873e14e019a07f387b4d577d6d1f9 Mon Sep 17 00:00:00 2001 From: Xin Long Date: Mon, 29 Oct 2018 23:10:29 +0800 Subject: sctp: clear the transport of some out_chunk_list chunks in sctp_assoc_rm_peer If a transport is removed by asconf but there still are some chunks with this transport queuing on out_chunk_list, later an use-after-free issue will be caused when accessing this transport from these chunks in sctp_outq_flush(). This is an old bug, we fix it by clearing the transport of these chunks in out_chunk_list when removing a transport in sctp_assoc_rm_peer(). Reported-by: syzbot+56a40ceee5fb35932f4d@syzkaller.appspotmail.com Signed-off-by: Xin Long Signed-off-by: David S. Miller --- net/sctp/associola.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'net/sctp') diff --git a/net/sctp/associola.c b/net/sctp/associola.c index a827a1f562bf..6a28b96e779e 100644 --- a/net/sctp/associola.c +++ b/net/sctp/associola.c @@ -499,8 +499,9 @@ void sctp_assoc_set_primary(struct sctp_association *asoc, void sctp_assoc_rm_peer(struct sctp_association *asoc, struct sctp_transport *peer) { - struct list_head *pos; - struct sctp_transport *transport; + struct sctp_transport *transport; + struct list_head *pos; + struct sctp_chunk *ch; pr_debug("%s: association:%p addr:%pISpc\n", __func__, asoc, &peer->ipaddr.sa); @@ -564,7 +565,6 @@ void sctp_assoc_rm_peer(struct sctp_association *asoc, */ if (!list_empty(&peer->transmitted)) { struct sctp_transport *active = asoc->peer.active_path; - struct sctp_chunk *ch; /* Reset the transport of each chunk on this list */ list_for_each_entry(ch, &peer->transmitted, @@ -586,6 +586,10 @@ void sctp_assoc_rm_peer(struct sctp_association *asoc, sctp_transport_hold(active); } + list_for_each_entry(ch, &asoc->outqueue.out_chunk_list, list) + if (ch->transport == peer) + ch->transport = NULL; + asoc->peer.transport_count--; sctp_transport_free(peer); -- cgit v1.2.3 From 713358369382cebf92f6e98ce2005f94e7344931 Mon Sep 17 00:00:00 2001 From: Xin Long Date: Mon, 29 Oct 2018 23:13:11 +0800 Subject: sctp: check policy more carefully when getting pr status When getting pr_assocstatus and pr_streamstatus by sctp_getsockopt, it doesn't correctly process the case when policy is set with SCTP_PR_SCTP_ALL | SCTP_PR_SCTP_MASK. It even causes a slab-out-of-bounds in sctp_getsockopt_pr_streamstatus(). This patch fixes it by return -EINVAL for this case. Fixes: 0ac1077e3a54 ("sctp: get pr_assoc and pr_stream all status with SCTP_PR_SCTP_ALL") Reported-by: syzbot+5da0d0a72a9e7d791748@syzkaller.appspotmail.com Suggested-by: Marcelo Ricardo Leitner Signed-off-by: Xin Long Signed-off-by: David S. Miller --- net/sctp/socket.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'net/sctp') diff --git a/net/sctp/socket.c b/net/sctp/socket.c index fc0386e8ff23..739f3e50120d 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -7083,14 +7083,15 @@ static int sctp_getsockopt_pr_assocstatus(struct sock *sk, int len, } policy = params.sprstat_policy; - if (!policy || (policy & ~(SCTP_PR_SCTP_MASK | SCTP_PR_SCTP_ALL))) + if (!policy || (policy & ~(SCTP_PR_SCTP_MASK | SCTP_PR_SCTP_ALL)) || + ((policy & SCTP_PR_SCTP_ALL) && (policy & SCTP_PR_SCTP_MASK))) goto out; asoc = sctp_id2assoc(sk, params.sprstat_assoc_id); if (!asoc) goto out; - if (policy & SCTP_PR_SCTP_ALL) { + if (policy == SCTP_PR_SCTP_ALL) { params.sprstat_abandoned_unsent = 0; params.sprstat_abandoned_sent = 0; for (policy = 0; policy <= SCTP_PR_INDEX(MAX); policy++) { @@ -7142,7 +7143,8 @@ static int sctp_getsockopt_pr_streamstatus(struct sock *sk, int len, } policy = params.sprstat_policy; - if (!policy || (policy & ~(SCTP_PR_SCTP_MASK | SCTP_PR_SCTP_ALL))) + if (!policy || (policy & ~(SCTP_PR_SCTP_MASK | SCTP_PR_SCTP_ALL)) || + ((policy & SCTP_PR_SCTP_ALL) && (policy & SCTP_PR_SCTP_MASK))) goto out; asoc = sctp_id2assoc(sk, params.sprstat_assoc_id); -- cgit v1.2.3