[PATCH 4.20 14/80] sctp: improve the events for sctp stream reset

Greg Kroah-Hartman
2019-02-04T10:57:33Z

From: Xin Long <lucien.xin@gmail.com>

[ Upstream commit 2e6dc4d95110becfe0ff4c3d4749c33ea166e9e7 ]

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/sctp/stream.c | 39 +++++++++++++++++----------------------
1 file changed, 17 insertions(+), 22 deletions(-)

--- a/net/sctp/stream.c
+++ b/net/sctp/stream.c
@@ -585,9 +585,9 @@ struct sctp_chunk *sctp_process_strreset
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
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
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

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
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
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) {