From 2e6dc4d95110becfe0ff4c3d4749c33ea166e9e7 Mon Sep 17 00:00:00 2001 From: Xin Long <lucien.xin@gmail.com> Date: Tue, 22 Jan 2019 02:39:34 +0800 Subject: 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> --- net/sctp/stream.c | 39 +++++++++++++++++---------------------- 1 file changed, 17 insertions(+), 22 deletions(-) (limited to 'net/sctp/stream.c') diff --git a/net/sctp/stream.c b/net/sctp/stream.c index 3892e7630f3a..6c188b06e5e1 100644 --- 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) { -- cgit v1.2.3 From 8220c870cb0f4eaa4e335c9645dbd9a1c461c1dd Mon Sep 17 00:00:00 2001 From: Xin Long <lucien.xin@gmail.com> Date: Tue, 22 Jan 2019 02:40:12 +0800 Subject: sctp: improve the events for sctp stream adding This patch is to improve sctp stream adding events in 2 places: 1. In sctp_process_strreset_addstrm_out(), move up SCTP_MAX_STREAM and in stream allocation failure checks, as the adding has to succeed after reconf_timer stops for the in stream adding request retransmission. 3. In sctp_process_strreset_addstrm_in(), no event should be sent, as no in or out stream is added here. Fixes: 50a41591f110 ("sctp: implement receiver-side procedures for the Add Outgoing Streams Request Parameter") Fixes: c5c4ebb3ab87 ("sctp: implement receiver-side procedures for the Add Incoming Streams Request 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> --- net/sctp/stream.c | 19 ++++++++----------- 1 file changed, 8 insertions(+), 11 deletions(-) (limited to 'net/sctp/stream.c') diff --git a/net/sctp/stream.c b/net/sctp/stream.c index 6c188b06e5e1..80e0ae5534ec 100644 --- a/net/sctp/stream.c +++ b/net/sctp/stream.c @@ -866,6 +866,14 @@ struct sctp_chunk *sctp_process_strreset_addstrm_out( if (!(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ)) goto out; + in = ntohs(addstrm->number_of_streams); + incnt = stream->incnt + in; + if (!in || incnt > SCTP_MAX_STREAM) + goto out; + + if (sctp_stream_alloc_in(stream, incnt, GFP_ATOMIC)) + goto out; + if (asoc->strreset_chunk) { if (!sctp_chunk_lookup_strreset_param( asoc, 0, SCTP_PARAM_RESET_ADD_IN_STREAMS)) { @@ -889,14 +897,6 @@ struct sctp_chunk *sctp_process_strreset_addstrm_out( } } - in = ntohs(addstrm->number_of_streams); - incnt = stream->incnt + in; - if (!in || incnt > SCTP_MAX_STREAM) - goto out; - - if (sctp_stream_alloc_in(stream, incnt, GFP_ATOMIC)) - goto out; - stream->incnt = incnt; result = SCTP_STRRESET_PERFORMED; @@ -966,9 +966,6 @@ struct sctp_chunk *sctp_process_strreset_addstrm_in( result = SCTP_STRRESET_PERFORMED; - *evp = sctp_ulpevent_make_stream_change_event(asoc, - 0, 0, ntohs(addstrm->number_of_streams), GFP_ATOMIC); - out: sctp_update_strreset_result(asoc, result); err: -- cgit v1.2.3 From cfe4bd7a257f6d6f81d3458d8c9d9ec4957539e6 Mon Sep 17 00:00:00 2001 From: Xin Long <lucien.xin@gmail.com> Date: Mon, 4 Feb 2019 03:27:58 +0800 Subject: sctp: check and update stream->out_curr when allocating stream_out Now when using stream reconfig to add out streams, stream->out will get re-allocated, and all old streams' information will be copied to the new ones and the old ones will be freed. So without stream->out_curr updated, next time when trying to send from stream->out_curr stream, a panic would be caused. This patch is to check and update stream->out_curr when allocating stream_out. v1->v2: - define fa_index() to get elem index from stream->out_curr. v2->v3: - repost with no change. Fixes: 5bbbbe32a431 ("sctp: introduce stream scheduler foundations") Reported-by: Ying Xu <yinxu@redhat.com> Reported-by: syzbot+e33a3a138267ca119c7d@syzkaller.appspotmail.com Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> --- net/sctp/stream.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) (limited to 'net/sctp/stream.c') diff --git a/net/sctp/stream.c b/net/sctp/stream.c index 80e0ae5534ec..f24633114dfd 100644 --- a/net/sctp/stream.c +++ b/net/sctp/stream.c @@ -84,6 +84,19 @@ static void fa_zero(struct flex_array *fa, size_t index, size_t count) } } +static size_t fa_index(struct flex_array *fa, void *elem, size_t count) +{ + size_t index = 0; + + while (count--) { + if (elem == flex_array_get(fa, index)) + break; + index++; + } + + return index; +} + /* Migrates chunks from stream queues to new stream queues if needed, * but not across associations. Also, removes those chunks to streams * higher than the new max. @@ -147,6 +160,13 @@ static int sctp_stream_alloc_out(struct sctp_stream *stream, __u16 outcnt, if (stream->out) { fa_copy(out, stream->out, 0, min(outcnt, stream->outcnt)); + if (stream->out_curr) { + size_t index = fa_index(stream->out, stream->out_curr, + stream->outcnt); + + BUG_ON(index == stream->outcnt); + stream->out_curr = flex_array_get(out, index); + } fa_free(stream->out); } -- cgit v1.2.3 From af98c5a78517c04adb5fd68bb64b1ad6fe3d473f Mon Sep 17 00:00:00 2001 From: Xin Long <lucien.xin@gmail.com> Date: Tue, 12 Feb 2019 18:51:01 +0800 Subject: sctp: set stream ext to NULL after freeing it in sctp_stream_outq_migrate In sctp_stream_init(), after sctp_stream_outq_migrate() freed the surplus streams' ext, but sctp_stream_alloc_out() returns -ENOMEM, stream->outcnt will not be set to 'outcnt'. With the bigger value on stream->outcnt, when closing the assoc and freeing its streams, the ext of those surplus streams will be freed again since those stream exts were not set to NULL after freeing in sctp_stream_outq_migrate(). Then the invalid-free issue reported by syzbot would be triggered. We fix it by simply setting them to NULL after freeing. Fixes: 5bbbbe32a431 ("sctp: introduce stream scheduler foundations") Reported-by: syzbot+58e480e7b28f2d890bfd@syzkaller.appspotmail.com Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> --- net/sctp/stream.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'net/sctp/stream.c') diff --git a/net/sctp/stream.c b/net/sctp/stream.c index f24633114dfd..2936ed17bf9e 100644 --- a/net/sctp/stream.c +++ b/net/sctp/stream.c @@ -144,8 +144,10 @@ static void sctp_stream_outq_migrate(struct sctp_stream *stream, } } - for (i = outcnt; i < stream->outcnt; i++) + for (i = outcnt; i < stream->outcnt; i++) { kfree(SCTP_SO(stream, i)->ext); + SCTP_SO(stream, i)->ext = NULL; + } } static int sctp_stream_alloc_out(struct sctp_stream *stream, __u16 outcnt, -- cgit v1.2.3