detect/content: account for distance variables

Under some cases (see the issue), the depth and offset values are used
twice. This commit disregards the distance variable (if any), when
computing the final depth.

Issue: 7390

src/detect-engine-content-inspection.c

@@ -182,6 +182,8 @@ static int DetectEngineContentInspectionInternal(DetectEngineThreadCtx *det_ctx,
                     }
 
                     if (stream_start_offset != 0 && prev_buffer_offset == 0) {
+                        SCLogDebug("stream_start_offset: %" PRIi32 ", depth %" PRIu32,
+                                stream_start_offset, depth);
                         if (depth <= stream_start_offset) {
                             goto no_match;
                         } else if (depth >= (stream_start_offset + buffer_len)) {
@@ -189,6 +191,8 @@ static int DetectEngineContentInspectionInternal(DetectEngineThreadCtx *det_ctx,
                         } else {
                             depth = depth - stream_start_offset;
                         }
+                        SCLogDebug("depth is now %" PRIu32 ", stream_start_offset: %" PRIi32, depth,
+                                stream_start_offset);
                     }
                 }
 
@@ -202,7 +206,10 @@ static int DetectEngineContentInspectionInternal(DetectEngineThreadCtx *det_ctx,
                             depth = prev_buffer_offset + cd->depth;
                         }
 
-                        SCLogDebug("cd->depth %"PRIu32", depth %"PRIu32, cd->depth, depth);
+                        SCLogDebug("cd->depth %" PRIu32 ", depth %" PRIu32
+                                   " , prev_offset %" PRIi32,
+                                cd->depth, depth, prev_buffer_offset);
+                        depth += offset;
                     }
                 }
 
@@ -246,8 +253,8 @@ static int DetectEngineContentInspectionInternal(DetectEngineThreadCtx *det_ctx,
             /* If the value came from a variable, make sure to adjust the depth so it's relative
              * to the offset value.
              */
-            if (cd->flags & (DETECT_CONTENT_DISTANCE_VAR|DETECT_CONTENT_OFFSET_VAR|DETECT_CONTENT_DEPTH_VAR)) {
-                 depth += offset;
+            if (cd->flags & (DETECT_CONTENT_OFFSET_VAR | DETECT_CONTENT_DEPTH_VAR)) {
+                depth += offset;
             }
 
             /* update offset with prev_offset if we're searching for