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Bug #4645

closed

TCP reassembly, failed assert app_progress > last_ack_abs, both sides need to be pruned

Added by Jeff Lucovsky about 1 year ago. Updated 4 months ago.

Status:
Closed
Priority:
Normal
Assignee:
Target version:
Affected Versions:
Effort:
Difficulty:
Label:

Description

Found by oss-fuzz
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35626

Minimized reproducer with suricata is
./src/suricata -r lolb.pcap -k none -c suricata.yaml --set stream.midstream=true

What happens is
- first packet (midstream) all ok (ack = 1)
- second packet, from the other side, ack is ok, but sequence indicates a gap from first packet ack (seq = 77)
- third packet, sequence ok, ack is increased since first packet confirming the gap (ack = 77) StreamTcpUpdateAppLayerProgress is called by AppLayerHandleTCPData at the end of if (flags & STREAM_GAP) {
- Fourth packet is in first direction (seq and ack meaningless)

At the end of third packet, the 76 gap does not get subtracted in app_progress_rel as StreamTcpPruneSession only considers the other stream


Files

lolb.pcap (984 Bytes) lolb.pcap Philippe Antoine, 06/30/2021 07:26 PM

Related issues 1 (0 open1 closed)

Copied from Bug #4549: TCP reassembly, failed assert app_progress > last_ack_abs, both sides need to be prunedClosedVictor JulienActions
Actions #1

Updated by Jeff Lucovsky about 1 year ago

  • Copied from Bug #4549: TCP reassembly, failed assert app_progress > last_ack_abs, both sides need to be pruned added
Actions #2

Updated by Victor Julien 11 months ago

  • Status changed from Assigned to Closed
Actions #3

Updated by Victor Julien 10 months ago

  • Private changed from Yes to No
Actions #4

Updated by Shivani Bhardwaj 6 months ago

  • Status changed from Closed to Assigned
  • Target version changed from 6.0.4 to 6.0.6
Actions #5

Updated by Jeff Lucovsky 4 months ago

  • Status changed from Assigned to In Progress
  • Assignee changed from Shivani Bhardwaj to Jeff Lucovsky

Cherry-pick commit(s):
- 1f43e1477f3c
- 3d6e733aa729

Actions #6

Updated by Jeff Lucovsky 4 months ago

  • Status changed from In Progress to In Review
Actions #8

Updated by Jeff Lucovsky 4 months ago

  • Status changed from In Review to Closed
Actions

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