Avoiding arithmetic ops with NULL pointer in nxt_unit_mmap_get

Found by UndefinedBehaviorSanitizer. Reviewed-by: Andrew Clayton <a.clayton@nginx.com>
nginx · Feb 22, 2024 · 8eb3653 · 8eb3653
1 parent e6571b8
commit 8eb3653
Showing 1 changed file with 6 additions and 0 deletions.
diff --git a/src/nxt_unit.c b/src/nxt_unit.c
@@ -3502,6 +3502,10 @@ nxt_unit_mmap_get(nxt_unit_ctx_t *ctx, nxt_unit_port_t *port,
 
     pthread_mutex_lock(&lib->outgoing.mutex);
 
+    if (nxt_slow_path(lib->outgoing.elts == NULL)) {
+        goto skip;
+    }
+
 retry:
 
     outgoing_size = lib->outgoing.size;
@@ -3598,6 +3602,8 @@ nxt_unit_mmap_get(nxt_unit_ctx_t *ctx, nxt_unit_port_t *port,
         goto retry;
     }
 
+skip:
+
     *c = 0;
     hdr = nxt_unit_new_mmap(ctx, port, *n);