[PATCH] stream/reassembly: improve progress tracking for GAP cases

When during raw reassembly it is detected that last ack is moved beyond
the progress and also beyond the data retrieved, update progress to the
last ack value.

Bug: #8272.
(cherry picked from commit ac1a514c7b57ea24f603020ef790c59b84143244)

Origin: upstream, https://github.com/OISF/suricata/commit/fecaa08f591c508b6486e7e9a2ee05636d1f9503.patch
Bug: https://redmine.openinfosecfoundation.org/issues/8365
Subject: Upstream fix for CVE-2026-31933

Gbp-Pq: Name CVE-2026-31933.patch

diff --git a/src/stream-tcp-reassemble.c b/src/stream-tcp-reassemble.c
index 31e338838824b937c6877cdb9719146b6342308a..37cbfeceea3631d138090e80cceda5e6bb0f4efd 100644 (file)
--- a/src/stream-tcp-reassemble.c
+++ b/src/stream-tcp-reassemble.c
@@ -1872,6 +1872,12 @@ static int StreamReassembleRawDo(const TcpSession *ssn, const TcpStream *stream,
             progress = mydata_offset;
             SCLogDebug("raw progress now %"PRIu64, progress);
 
+            /* data is beyond the progress we'd like, and also beyond the last ack:
+             * there is a gap and we can't expect it to get filled anymore. */
+        } else if (mydata_offset > progress && mydata_offset == re) {
+            SCLogDebug("mydata_offset %" PRIu64 ", progress %" PRIu64 ", re %" PRIu64,
+                    mydata_offset, progress, re);
+            progress = re;
         } else {
             SCLogDebug("not increasing progress, data gap => mydata_offset "
                        "%"PRIu64" != progress %"PRIu64, mydata_offset, progress);