detect: fix rule inspection order

Fix rules from the 'match' list getting added to the tx candidates list
unsorted. In some cases this could lead to the same sid getting inspected
twice leading to a DEBUG_VALIDATION_BUG_ON trigger.

Bug: #5144.
(cherry picked from commit 4bb00964ac22f0f96704cf5befca76d056763142)

diff --git a/src/detect.c b/src/detect.c
index 49ea27a81440bc89df01a8ce28ec08f98a6c4db8..b8321ab8a528af6375884e9b67f660bf26487f64 100644 (file)
--- a/src/detect.c
+++ b/src/detect.c
@@ -1318,6 +1318,7 @@ static void DetectRunTx(ThreadVars *tv,
         }
         tx_id_min = tx.tx_id + 1; // next look for cur + 1
 
+        bool do_sort = false; // do we need to sort the tx candidate list?
         uint32_t array_idx = 0;
         uint32_t total_rules = det_ctx->match_array_cnt;
         total_rules += (tx.de_state ? tx.de_state->cnt : 0);
@@ -1368,8 +1369,9 @@ static void DetectRunTx(ThreadVars *tv,
                         tx.tx_ptr, tx.tx_id, s->id, id);
             }
         }
-        SCLogDebug("%p/%"PRIu64" rules added from 'match' list: %u",
-                tx.tx_ptr, tx.tx_id, array_idx - x); (void)x;
+        do_sort = (array_idx > x); // sort if match added anything
+        SCLogDebug("%p/%" PRIu64 " rules added from 'match' list: %u", tx.tx_ptr, tx.tx_id,
+                array_idx - x);
 
         /* merge stored state into results */
         if (tx.de_state != NULL) {
@@ -1409,13 +1411,13 @@ static void DetectRunTx(ThreadVars *tv,
                     array_idx++;
                 }
             }
-            if (old && old != array_idx) {
-                qsort(det_ctx->tx_candidates, array_idx, sizeof(RuleMatchCandidateTx),
-                        DetectRunTxSortHelper);
-
-                SCLogDebug("%p/%"PRIu64" rules added from 'continue' list: %u",
-                        tx.tx_ptr, tx.tx_id, array_idx - old);
-            }
+            do_sort |= (old && old != array_idx); // sort if continue list adds sids
+            SCLogDebug("%p/%" PRIu64 " rules added from 'continue' list: %u", tx.tx_ptr, tx.tx_id,
+                    array_idx - old);
+        }
+        if (do_sort) {
+            qsort(det_ctx->tx_candidates, array_idx, sizeof(RuleMatchCandidateTx),
+                    DetectRunTxSortHelper);
         }
 
         det_ctx->tx_id = tx.tx_id;