The branch main has been updated by tuexen: URL: https://cgit.FreeBSD.org/src/commit/?id=101a0f09e8baf8293e1eeb591de18caf15e49e00
commit 101a0f09e8baf8293e1eeb591de18caf15e49e00 Author: Michael Tuexen <[email protected]> AuthorDate: 2024-08-03 11:27:18 +0000 Commit: Michael Tuexen <[email protected]> CommitDate: 2024-08-03 11:27:18 +0000 sctp: improve input validation for data chunks fsn_included should only be considered, if first_frag_seen is true. Also, fix the resetting of the control structure, if stream queues are flushed. This fixes a bug where a legitimate message sequence was incorrectly classified as illegitimate. Thanks to Victor Boivie for reporting the issue on the userland stack. MFC after: 3 days --- sys/netinet/sctp_indata.c | 35 +++++++++++++++++------------------ 1 file changed, 17 insertions(+), 18 deletions(-) diff --git a/sys/netinet/sctp_indata.c b/sys/netinet/sctp_indata.c index 4c40e0de4326..693de313b970 100644 --- a/sys/netinet/sctp_indata.c +++ b/sys/netinet/sctp_indata.c @@ -746,21 +746,6 @@ sctp_build_readq_entry_from_ctl(struct sctp_queued_to_read *nc, struct sctp_queu nc->do_not_ref_stcb = control->do_not_ref_stcb; } -static void -sctp_reset_a_control(struct sctp_queued_to_read *control, - struct sctp_inpcb *inp, uint32_t tsn) -{ - control->fsn_included = tsn; - if (control->on_read_q) { - /* - * We have to purge it from there, hopefully this will work - * :-) - */ - TAILQ_REMOVE(&inp->read_queue, control, next); - control->on_read_q = 0; - } -} - static int sctp_handle_old_unordered_data(struct sctp_tcb *stcb, struct sctp_association *asoc, @@ -1922,7 +1907,8 @@ sctp_process_a_data_chunk(struct sctp_tcb *stcb, struct sctp_association *asoc, SCTP_SNPRINTF(msg, sizeof(msg), "Duplicate MID=%8.8x detected.", mid); goto err_out; } else { - if ((tsn == control->fsn_included + 1) && + if ((control->first_frag_seen) && + (tsn == control->fsn_included + 1) && (control->end_added == 0)) { SCTP_SNPRINTF(msg, sizeof(msg), "Illegal message sequence, missing end for MID: %8.8x", @@ -5430,12 +5416,25 @@ sctp_flush_reassm_for_str_seq(struct sctp_tcb *stcb, sctp_free_a_chunk(stcb, chk, SCTP_SO_NOT_LOCKED); } if (!TAILQ_EMPTY(&control->reasm)) { - /* This has to be old data, unordered */ + KASSERT(!asoc->idata_supported, + ("Reassembly queue not empty for I-DATA")); + KASSERT(!ordered, + ("Reassembly queue not empty for ordered data")); if (control->data) { sctp_m_freem(control->data); control->data = NULL; } - sctp_reset_a_control(control, stcb->sctp_ep, cumtsn); + control->fsn_included = 0xffffffff; + control->first_frag_seen = 0; + control->last_frag_seen = 0; + if (control->on_read_q) { + /* + * We have to purge it from there, hopefully this + * will work :-) + */ + TAILQ_REMOVE(&stcb->sctp_ep->read_queue, control, next); + control->on_read_q = 0; + } chk = TAILQ_FIRST(&control->reasm); if (chk->rec.data.rcv_flags & SCTP_DATA_FIRST_FRAG) { TAILQ_REMOVE(&control->reasm, chk, sctp_next);
