Merge branch 'sctp-stream-reconfig-fixes'

Xin Long says:

====================
sctp: a bunch of fixes for stream reconfig

This patchset is to make stream reset and asoc reset work more correctly
for stream reconfig.

Thank to Marcelo making them very clear.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 65 insertions, 12 deletions

diff --git a/net/sctp/stream.c b/net/sctp/stream.c
index a11db21dc8a0..a20145b3a949 100644
--- a/net/sctp/stream.c
+++ b/net/sctp/stream.c
@@ -254,6 +254,30 @@ static int sctp_send_reconf(struct sctp_association *asoc,
         return retval;
 }
 
+static bool sctp_stream_outq_is_empty(struct sctp_stream *stream,
+                                      __u16 str_nums, __be16 *str_list)
+{
+        struct sctp_association *asoc;
+        __u16 i;
+
+        asoc = container_of(stream, struct sctp_association, stream);
+        if (!asoc->outqueue.out_qlen)
+                return true;
+
+        if (!str_nums)
+                return false;
+
+        for (i = 0; i < str_nums; i++) {
+                __u16 sid = ntohs(str_list[i]);
+
+                if (stream->out[sid].ext &&
+                    !list_empty(&stream->out[sid].ext->outq))
+                        return false;
+        }
+
+        return true;
+}
+
 int sctp_send_reset_streams(struct sctp_association *asoc,
                             struct sctp_reset_streams *params)
 {
@@ -317,6 +341,11 @@ int sctp_send_reset_streams(struct sctp_association *asoc,
         for (i = 0; i < str_nums; i++)
                 nstr_list[i] = htons(str_list[i]);
 
+        if (out && !sctp_stream_outq_is_empty(stream, str_nums, nstr_list)) {
+                retval = -EAGAIN;
+                goto out;
+        }
+
         chunk = sctp_make_strreset_req(asoc, str_nums, nstr_list, out, in);
 
         kfree(nstr_list);
@@ -377,6 +406,9 @@ int sctp_send_reset_assoc(struct sctp_association *asoc)
         if (asoc->strreset_outstanding)
                 return -EINPROGRESS;
 
+        if (!sctp_outq_is_empty(&asoc->outqueue))
+                return -EAGAIN;
+
         chunk = sctp_make_strreset_tsnreq(asoc);
         if (!chunk)
                 return -ENOMEM;
@@ -563,7 +595,7 @@ struct sctp_chunk *sctp_process_strreset_outreq(
                 flags = SCTP_STREAM_RESET_INCOMING_SSN;
         }
 
-        nums = (ntohs(param.p->length) - sizeof(*outreq)) / 2;
+        nums = (ntohs(param.p->length) - sizeof(*outreq)) / sizeof(__u16);
         if (nums) {
                 str_p = outreq->list_of_streams;
                 for (i = 0; i < nums; i++) {
@@ -627,7 +659,7 @@ struct sctp_chunk *sctp_process_strreset_inreq(
                 goto out;
         }
 
-        nums = (ntohs(param.p->length) - sizeof(*inreq)) / 2;
+        nums = (ntohs(param.p->length) - sizeof(*inreq)) / sizeof(__u16);
         str_p = inreq->list_of_streams;
         for (i = 0; i < nums; i++) {
                 if (ntohs(str_p[i]) >= stream->outcnt) {
@@ -636,6 +668,12 @@ struct sctp_chunk *sctp_process_strreset_inreq(
                 }
         }
 
+        if (!sctp_stream_outq_is_empty(stream, nums, str_p)) {
+                result = SCTP_STRRESET_IN_PROGRESS;
+                asoc->strreset_inseq--;
+                goto err;
+        }
+
         chunk = sctp_make_strreset_req(asoc, nums, str_p, 1, 0);
         if (!chunk)
                 goto out;
@@ -687,12 +725,18 @@ struct sctp_chunk *sctp_process_strreset_tsnreq(
                 i = asoc->strreset_inseq - request_seq - 1;
                 result = asoc->strreset_result[i];
                 if (result == SCTP_STRRESET_PERFORMED) {
-                        next_tsn = asoc->next_tsn;
+                        next_tsn = asoc->ctsn_ack_point + 1;
                         init_tsn =
                                 sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + 1;
                 }
                 goto err;
         }
+
+        if (!sctp_outq_is_empty(&asoc->outqueue)) {
+                result = SCTP_STRRESET_IN_PROGRESS;
+                goto err;
+        }
+
         asoc->strreset_inseq++;
 
         if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
@@ -703,9 +747,10 @@ struct sctp_chunk *sctp_process_strreset_tsnreq(
                 goto out;
         }
 
-        /* G3: The same processing as though a SACK chunk with no gap report
-         *     and a cumulative TSN ACK of the Sender's Next TSN minus 1 were
-         *     received MUST be performed.
+        /* G4: The same processing as though a FWD-TSN chunk (as defined in
+         *     [RFC3758]) with all streams affected and a new cumulative TSN
+         *     ACK of the Receiver's Next TSN minus 1 were received MUST be
+         *     performed.
          */
         max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
         sctp_ulpq_reasm_flushtsn(&asoc->ulpq, max_tsn_seen);
@@ -720,10 +765,9 @@ struct sctp_chunk *sctp_process_strreset_tsnreq(
         sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
                          init_tsn, GFP_ATOMIC);
 
-        /* G4: The same processing as though a FWD-TSN chunk (as defined in
-         *     [RFC3758]) with all streams affected and a new cumulative TSN
-         *     ACK of the Receiver's Next TSN minus 1 were received MUST be
-         *     performed.
+        /* G3: The same processing as though a SACK chunk with no gap report
+         *     and a cumulative TSN ACK of the Sender's Next TSN minus 1 were
+         *     received MUST be performed.
          */
         sctp_outq_free(&asoc->outqueue);
 
@@ -927,7 +971,8 @@ struct sctp_chunk *sctp_process_strreset_resp(
 
                 outreq = (struct sctp_strreset_outreq *)req;
                 str_p = outreq->list_of_streams;
-                nums = (ntohs(outreq->param_hdr.length) - sizeof(*outreq)) / 2;
+                nums = (ntohs(outreq->param_hdr.length) - sizeof(*outreq)) /
+                       sizeof(__u16);
 
                 if (result == SCTP_STRRESET_PERFORMED) {
                         if (nums) {
@@ -956,7 +1001,8 @@ struct sctp_chunk *sctp_process_strreset_resp(
 
                 inreq = (struct sctp_strreset_inreq *)req;
                 str_p = inreq->list_of_streams;
-                nums = (ntohs(inreq->param_hdr.length) - sizeof(*inreq)) / 2;
+                nums = (ntohs(inreq->param_hdr.length) - sizeof(*inreq)) /
+                       sizeof(__u16);
 
                 *evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
                         nums, str_p, GFP_ATOMIC);
@@ -975,6 +1021,7 @@ struct sctp_chunk *sctp_process_strreset_resp(
                 if (result == SCTP_STRRESET_PERFORMED) {
                         __u32 mtsn = sctp_tsnmap_get_max_tsn_seen(
                                                 &asoc->peer.tsn_map);
+                        LIST_HEAD(temp);
 
                         sctp_ulpq_reasm_flushtsn(&asoc->ulpq, mtsn);
                         sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
@@ -983,7 +1030,13 @@ struct sctp_chunk *sctp_process_strreset_resp(
                                          SCTP_TSN_MAP_INITIAL,
                                          stsn, GFP_ATOMIC);
 
+                        /* Clean up sacked and abandoned queues only. As the
+                         * out_chunk_list may not be empty, splice it to temp,
+                         * then get it back after sctp_outq_free is done.
+                         */
+                        list_splice_init(&asoc->outqueue.out_chunk_list, &temp);
                         sctp_outq_free(&asoc->outqueue);
+                        list_splice_init(&temp, &asoc->outqueue.out_chunk_list);
 
                         asoc->next_tsn = rtsn;
                         asoc->ctsn_ack_point = asoc->next_tsn - 1;