sctp: improve the events for sctp stream reset

This patch is to improve sctp stream reset events in 4 places:

  1. In sctp_process_strreset_outreq(), the flag should always be set with
     SCTP_STREAM_RESET_INCOMING_SSN instead of OUTGOING, as receiver's in
     stream is reset here.
  2. In sctp_process_strreset_outreq(), move up SCTP_STRRESET_ERR_WRONG_SSN
     check, as the reset has to succeed after reconf_timer stops for the
     in stream reset request retransmission.
  3. In sctp_process_strreset_inreq(), no event should be sent, as no in
     or out stream is reset here.
  4. In sctp_process_strreset_resp(), SCTP_STREAM_RESET_INCOMING_SSN or
     OUTGOING event should always be sent for stream reset requests, no
     matter it fails or succeeds to process the request.

Fixes: 810544764536 ("sctp: implement receiver-side procedures for the Outgoing SSN Reset Request Parameter")
Fixes: 16e1a91965b0 ("sctp: implement receiver-side procedures for the Incoming SSN Reset Request Parameter")
Fixes: 11ae76e67a17 ("sctp: implement receiver-side procedures for the Reconf Response Parameter")
Reported-by: Ying Xu <yinxu@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/sctp/stream.c b/net/sctp/stream.c
index 3892e76..6c188b0 100644 (file)
--- a/net/sctp/stream.c
+++ b/net/sctp/stream.c
@@ -585,9 +585,9 @@ struct sctp_chunk *sctp_process_strreset_outreq(
        struct sctp_strreset_outreq *outreq = param.v;
        struct sctp_stream *stream = &asoc->stream;
        __u32 result = SCTP_STRRESET_DENIED;
-       __u16 i, nums, flags = 0;
        __be16 *str_p = NULL;
        __u32 request_seq;
+       __u16 i, nums;
 
        request_seq = ntohl(outreq->request_seq);
 
@@ -615,6 +615,15 @@ struct sctp_chunk *sctp_process_strreset_outreq(
        if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
                goto out;
 
+       nums = (ntohs(param.p->length) - sizeof(*outreq)) / sizeof(__u16);
+       str_p = outreq->list_of_streams;
+       for (i = 0; i < nums; i++) {
+               if (ntohs(str_p[i]) >= stream->incnt) {
+                       result = SCTP_STRRESET_ERR_WRONG_SSN;
+                       goto out;
+               }
+       }
+
        if (asoc->strreset_chunk) {
                if (!sctp_chunk_lookup_strreset_param(
                                asoc, outreq->response_seq,
@@ -637,32 +646,19 @@ struct sctp_chunk *sctp_process_strreset_outreq(
                        sctp_chunk_put(asoc->strreset_chunk);
                        asoc->strreset_chunk = NULL;
                }
-
-               flags = SCTP_STREAM_RESET_INCOMING_SSN;
        }
 
-       nums = (ntohs(param.p->length) - sizeof(*outreq)) / sizeof(__u16);
-       if (nums) {
-               str_p = outreq->list_of_streams;
-               for (i = 0; i < nums; i++) {
-                       if (ntohs(str_p[i]) >= stream->incnt) {
-                               result = SCTP_STRRESET_ERR_WRONG_SSN;
-                               goto out;
-                       }
-               }
-
+       if (nums)
                for (i = 0; i < nums; i++)
                        SCTP_SI(stream, ntohs(str_p[i]))->mid = 0;
-       } else {
+       else
                for (i = 0; i < stream->incnt; i++)
                        SCTP_SI(stream, i)->mid = 0;
-       }
 
        result = SCTP_STRRESET_PERFORMED;
 
        *evp = sctp_ulpevent_make_stream_reset_event(asoc,
-               flags | SCTP_STREAM_RESET_OUTGOING_SSN, nums, str_p,
-               GFP_ATOMIC);
+               SCTP_STREAM_RESET_INCOMING_SSN, nums, str_p, GFP_ATOMIC);
 
 out:
        sctp_update_strreset_result(asoc, result);
@@ -738,9 +734,6 @@ struct sctp_chunk *sctp_process_strreset_inreq(
 
        result = SCTP_STRRESET_PERFORMED;
 
-       *evp = sctp_ulpevent_make_stream_reset_event(asoc,
-               SCTP_STREAM_RESET_INCOMING_SSN, nums, str_p, GFP_ATOMIC);
-
 out:
        sctp_update_strreset_result(asoc, result);
 err:
@@ -1036,10 +1029,10 @@ struct sctp_chunk *sctp_process_strreset_resp(
                                        sout->mid_uo = 0;
                                }
                        }
-
-                       flags = SCTP_STREAM_RESET_OUTGOING_SSN;
                }
 
+               flags |= SCTP_STREAM_RESET_OUTGOING_SSN;
+
                for (i = 0; i < stream->outcnt; i++)
                        SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
 
@@ -1058,6 +1051,8 @@ struct sctp_chunk *sctp_process_strreset_resp(
                nums = (ntohs(inreq->param_hdr.length) - sizeof(*inreq)) /
                       sizeof(__u16);
 
+               flags |= SCTP_STREAM_RESET_INCOMING_SSN;
+
                *evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
                        nums, str_p, GFP_ATOMIC);
        } else if (req->type == SCTP_PARAM_RESET_TSN_REQUEST) {