kernel.git/net/sctp/stream.c, branch linux-4.19.y

sctp: shrink stream outq when fails to do addstream reconf

2020-07-31T16:37:48Z

[ Upstream commit 3ecdda3e9ad837cf9cb41b6faa11b1af3a5abc0c ] When adding a stream with stream reconf, the new stream firstly is in CLOSED state but new out chunks can still be enqueued. Then once gets the confirmation from the peer, the state will change to OPEN. However, if the peer denies, it needs to roll back the stream. But when doing that, it only sets the stream outcnt back, and the chunks already in the new stream don't get purged. It caused these chunks can still be dequeued in sctp_outq_dequeue_data(). As its stream is still in CLOSE, the chunk will be enqueued to the head again by sctp_outq_head_data(). This chunk will never be sent out, and the chunks after it can never be dequeued. The assoc will be 'hung' in a dead loop of sending this chunk. To fix it, this patch is to purge these chunks already in the new stream by calling sctp_stream_shrink_out() when failing to do the addstream reconf. Fixes: 11ae76e67a17 ("sctp: implement receiver-side procedures for the Reconf Response Parameter") Reported-by: Ying Xu Signed-off-by: Xin Long Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sctp: shrink stream outq only when new outcnt < old outcnt

2020-07-31T16:37:48Z

[ Upstream commit 8f13399db22f909a35735bf8ae2f932e0c8f0e30 ] It's not necessary to go list_for_each for outq->out_chunk_list when new outcnt >= old outcnt, as no chunk with higher sid than new (outcnt - 1) exists in the outqueue. While at it, also move the list_for_each code in a new function sctp_stream_shrink_out(), which will be used in the next patch. Signed-off-by: Xin Long Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sctp: fix memleak in sctp_send_reset_streams

2019-08-25T08:48:04Z

[ Upstream commit 6d5afe20397b478192ed8c38ec0ee10fa3aec649 ] If the stream outq is not empty, need to kfree nstr_list. Fixes: d570a59c5b5f ("sctp: only allow the out stream reset when the stream outq is empty") Reported-by: Hulk Robot Signed-off-by: zhengbin Acked-by: Marcelo Ricardo Leitner Acked-by: Neil Horman Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

sctp: fix error handling on stream scheduler initialization

2019-07-28T06:29:25Z

[ Upstream commit 4d1415811e492d9a8238f8a92dd0d51612c788e9 ] It allocates the extended area for outbound streams only on sendmsg calls, if they are not yet allocated. When using the priority stream scheduler, this initialization may imply into a subsequent allocation, which may fail. In this case, it was aborting the stream scheduler initialization but leaving the ->ext pointer (allocated) in there, thus in a partially initialized state. On a subsequent call to sendmsg, it would notice the ->ext pointer in there, and trip on uninitialized stuff when trying to schedule the data chunk. The fix is undo the ->ext initialization if the stream scheduler initialization fails and avoid the partially initialized state. Although syzkaller bisected this to commit 4ff40b86262b ("sctp: set chunk transport correctly when it's a new asoc"), this bug was actually introduced on the commit I marked below. Reported-by: syzbot+c1a380d42b190ad1e559@syzkaller.appspotmail.com Fixes: 5bbbbe32a431 ("sctp: introduce stream scheduler foundations") Tested-by: Xin Long Signed-off-by: Marcelo Ricardo Leitner Acked-by: Neil Horman Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sctp: remove sched init from sctp_stream_init

2019-03-19T12:12:39Z

[ Upstream commit 2e990dfd13974d9eae493006f42ffb48707970ef ] syzbot reported a NULL-ptr deref caused by that sched->init() in sctp_stream_init() set stream->rr_next = NULL. kasan: GPF could be caused by NULL-ptr deref or user memory access RIP: 0010:sctp_sched_rr_dequeue+0xd3/0x170 net/sctp/stream_sched_rr.c:141 Call Trace: sctp_outq_dequeue_data net/sctp/outqueue.c:90 [inline] sctp_outq_flush_data net/sctp/outqueue.c:1079 [inline] sctp_outq_flush+0xba2/0x2790 net/sctp/outqueue.c:1205 All sched info is saved in sout->ext now, in sctp_stream_init() sctp_stream_alloc_out() will not change it, there's no need to call sched->init() again, since sctp_outq_init() has already done it. Fixes: 5bbbbe32a431 ("sctp: introduce stream scheduler foundations") Reported-by: syzbot+4c9934f20522c0efd657@syzkaller.appspotmail.com Signed-off-by: Xin Long Acked-by: Neil Horman Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sctp: set stream ext to NULL after freeing it in sctp_stream_outq_migrate

2019-02-27T09:08:58Z

[ Upstream commit af98c5a78517c04adb5fd68bb64b1ad6fe3d473f ] 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 Acked-by: Neil Horman Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sctp: check and update stream->out_curr when allocating stream_out

2019-02-12T18:47:22Z

[ Upstream commit cfe4bd7a257f6d6f81d3458d8c9d9ec4957539e6 ] 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 Reported-by: syzbot+e33a3a138267ca119c7d@syzkaller.appspotmail.com Signed-off-by: Xin Long Acked-by: Neil Horman Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sctp: improve the events for sctp stream adding

2019-02-06T16:30:08Z

[ Upstream commit 8220c870cb0f4eaa4e335c9645dbd9a1c461c1dd ] 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 Signed-off-by: Xin Long Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sctp: improve the events for sctp stream reset

2019-02-06T16:30:07Z

[ 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 Signed-off-by: Xin Long Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sctp: not increase stream's incnt before sending addstrm_in request

2018-11-23T07:17:06Z

[ Upstream commit e1e46479847e66f78f79d8c24d5169a5954b3fc2 ] 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 Signed-off-by: Greg Kroah-Hartman