From 02968ccf0125d39b08ecef5946300a8a873c0942 Mon Sep 17 00:00:00 2001 From: Xin Long Date: Sun, 18 Nov 2018 15:07:38 +0800 Subject: sctp: count sk_wmem_alloc by skb truesize in sctp_packet_transmit Now sctp increases sk_wmem_alloc by 1 when doing set_owner_w for the skb allocked in sctp_packet_transmit and decreases by 1 when freeing this skb. But when this skb goes through networking stack, some subcomponents might change skb->truesize and add the same amount on sk_wmem_alloc. However sctp doesn't know the amount to decrease by, it would cause a leak on sk->sk_wmem_alloc and the sock can never be freed. Xiumei found this issue when it hit esp_output_head() by using sctp over ipsec, where skb->truesize is added and so is sk->sk_wmem_alloc. Since sctp has used sk_wmem_queued to count for writable space since Commit cd305c74b0f8 ("sctp: use sk_wmem_queued to check for writable space"), it's ok to fix it by counting sk_wmem_alloc by skb truesize in sctp_packet_transmit. Fixes: cac2661c53f3 ("esp4: Avoid skb_cow_data whenever possible") Reported-by: Xiumei Mu Signed-off-by: Xin Long Signed-off-by: David S. Miller --- net/sctp/output.c | 21 +-------------------- 1 file changed, 1 insertion(+), 20 deletions(-) (limited to 'net/sctp') diff --git a/net/sctp/output.c b/net/sctp/output.c index 67939ad99c01..88dfa6ae1fb4 100644 --- a/net/sctp/output.c +++ b/net/sctp/output.c @@ -396,25 +396,6 @@ finish: return retval; } -static void sctp_packet_release_owner(struct sk_buff *skb) -{ - sk_free(skb->sk); -} - -static void sctp_packet_set_owner_w(struct sk_buff *skb, struct sock *sk) -{ - skb_orphan(skb); - skb->sk = sk; - skb->destructor = sctp_packet_release_owner; - - /* - * The data chunks have already been accounted for in sctp_sendmsg(), - * therefore only reserve a single byte to keep socket around until - * the packet has been transmitted. - */ - refcount_inc(&sk->sk_wmem_alloc); -} - static void sctp_packet_gso_append(struct sk_buff *head, struct sk_buff *skb) { if (SCTP_OUTPUT_CB(head)->last == head) @@ -601,7 +582,7 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp) if (!head) goto out; skb_reserve(head, packet->overhead + MAX_HEADER); - sctp_packet_set_owner_w(head, sk); + skb_set_owner_w(head, sk); /* set sctp header */ sh = skb_push(head, sizeof(struct sctphdr)); -- cgit v1.2.3 From cc3ccf26f0649089b3a34a2781977755ea36e72c Mon Sep 17 00:00:00 2001 From: Xin Long Date: Sun, 18 Nov 2018 15:21:53 +0800 Subject: sctp: not allow to set asoc prsctp_enable by sockopt As rfc7496#section4.5 says about SCTP_PR_SUPPORTED: This socket option allows the enabling or disabling of the negotiation of PR-SCTP support for future associations. For existing associations, it allows one to query whether or not PR-SCTP support was negotiated on a particular association. It means only sctp sock's prsctp_enable can be set. Note that for the limitation of SCTP_{CURRENT|ALL}_ASSOC, we will add it when introducing SCTP_{FUTURE|CURRENT|ALL}_ASSOC for linux sctp in another patchset. v1->v2: - drop the params.assoc_id check as Neil suggested. Fixes: 28aa4c26fce2 ("sctp: add SCTP_PR_SUPPORTED on sctp sockopt") Reported-by: Ying Xu Signed-off-by: Xin Long Signed-off-by: David S. Miller --- net/sctp/socket.c | 26 +++++--------------------- 1 file changed, 5 insertions(+), 21 deletions(-) (limited to 'net/sctp') diff --git a/net/sctp/socket.c b/net/sctp/socket.c index 739f3e50120d..bf618d1b41fd 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -3940,32 +3940,16 @@ static int sctp_setsockopt_pr_supported(struct sock *sk, unsigned int optlen) { struct sctp_assoc_value params; - struct sctp_association *asoc; - int retval = -EINVAL; if (optlen != sizeof(params)) - goto out; - - if (copy_from_user(¶ms, optval, optlen)) { - retval = -EFAULT; - goto out; - } - - asoc = sctp_id2assoc(sk, params.assoc_id); - if (asoc) { - asoc->prsctp_enable = !!params.assoc_value; - } else if (!params.assoc_id) { - struct sctp_sock *sp = sctp_sk(sk); + return -EINVAL; - sp->ep->prsctp_enable = !!params.assoc_value; - } else { - goto out; - } + if (copy_from_user(¶ms, optval, optlen)) + return -EFAULT; - retval = 0; + sctp_sk(sk)->ep->prsctp_enable = !!params.assoc_value; -out: - return retval; + return 0; } static int sctp_setsockopt_default_prinfo(struct sock *sk, -- cgit v1.2.3 From 69fec325a64383667b8a35df5d48d6ce52fb2782 Mon Sep 17 00:00:00 2001 From: Xin Long Date: Sun, 18 Nov 2018 16:14:47 +0800 Subject: Revert "sctp: remove sctp_transport_pmtu_check" This reverts commit 22d7be267eaa8114dcc28d66c1c347f667d7878a. The dst's mtu in transport can be updated by a non sctp place like in xfrm where the MTU information didn't get synced between asoc, transport and dst, so it is still needed to do the pmtu check in sctp_packet_config. Acked-by: Neil Horman Signed-off-by: David S. Miller --- include/net/sctp/sctp.h | 12 ++++++++++++ net/sctp/output.c | 3 +++ 2 files changed, 15 insertions(+) (limited to 'net/sctp') diff --git a/include/net/sctp/sctp.h b/include/net/sctp/sctp.h index 8c2caa370e0f..ab9242e51d9e 100644 --- a/include/net/sctp/sctp.h +++ b/include/net/sctp/sctp.h @@ -608,4 +608,16 @@ static inline __u32 sctp_dst_mtu(const struct dst_entry *dst) SCTP_DEFAULT_MINSEGMENT)); } +static inline bool sctp_transport_pmtu_check(struct sctp_transport *t) +{ + __u32 pmtu = sctp_dst_mtu(t->dst); + + if (t->pathmtu == pmtu) + return true; + + t->pathmtu = pmtu; + + return false; +} + #endif /* __net_sctp_h__ */ diff --git a/net/sctp/output.c b/net/sctp/output.c index 88dfa6ae1fb4..b0e74a3e77ec 100644 --- a/net/sctp/output.c +++ b/net/sctp/output.c @@ -118,6 +118,9 @@ void sctp_packet_config(struct sctp_packet *packet, __u32 vtag, sctp_transport_route(tp, NULL, sp); if (asoc->param_flags & SPP_PMTUD_ENABLE) sctp_assoc_sync_pmtu(asoc); + } else if (!sctp_transport_pmtu_check(tp)) { + if (asoc->param_flags & SPP_PMTUD_ENABLE) + sctp_assoc_sync_pmtu(asoc); } if (asoc->pmtu_pending) { -- cgit v1.2.3 From e1e46479847e66f78f79d8c24d5169a5954b3fc2 Mon Sep 17 00:00:00 2001 From: Xin Long Date: Sun, 18 Nov 2018 21:59:49 +0800 Subject: sctp: not increase stream's incnt before sending addstrm_in request Different from processing the addstrm_out request, The receiver handles an addstrm_in request by sending back an addstrm_out request to the sender who will increase its stream's in and incnt later. Now stream->incnt has been increased since it sent out the addstrm_in request in sctp_send_add_streams(), with the wrong stream->incnt will even cause crash when copying stream info from the old stream's in to the new one's in sctp_process_strreset_addstrm_out(). This patch is to fix it by simply removing the stream->incnt change from sctp_send_add_streams(). Fixes: 242bd2d519d7 ("sctp: implement sender-side procedures for Add Incoming/Outgoing Streams Request Parameter") Reported-by: Jianwen Ji Signed-off-by: Xin Long Signed-off-by: David S. Miller --- net/sctp/stream.c | 1 - 1 file changed, 1 deletion(-) (limited to 'net/sctp') diff --git a/net/sctp/stream.c b/net/sctp/stream.c index ffb940d3b57c..3892e7630f3a 100644 --- a/net/sctp/stream.c +++ b/net/sctp/stream.c @@ -535,7 +535,6 @@ int sctp_send_add_streams(struct sctp_association *asoc, goto out; } - stream->incnt = incnt; stream->outcnt = outcnt; asoc->strreset_outstanding = !!out + !!in; -- cgit v1.2.3