From ffbc446e3b338c784c345b9340f2eccf6359ddab Mon Sep 17 00:00:00 2001
From: "Artem S. Povalyukhin" <artem.povaluhin@gmail.com>
Date: Thu, 21 Nov 2019 22:31:14 +0300
Subject: [PATCH] Fixed hash collision for empty string key.

The issue was introduced in 10a19a2e1d4f.
---
 src/njs_object.c         | 2 +-
 src/njs_object.h         | 1 +
 src/njs_value.h          | 1 +
 src/test/njs_unit_test.c | 4 ++++
 4 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/njs_object.c b/src/njs_object.c
index 34ef9d17..088aef68 100644
--- a/src/njs_object.c
+++ b/src/njs_object.c
@@ -171,7 +171,7 @@ njs_object_hash_test(njs_lvlhsh_query_t *lhq, void *data)
 
     if (njs_slow_path(njs_is_symbol(name))) {
         return ((njs_symbol_key(name) == lhq->key_hash)
-                && lhq->key.length == 0) ? NJS_OK : NJS_DECLINED;
+                && lhq->key.start == NULL) ? NJS_OK : NJS_DECLINED;
     }
 
     /* string. */
diff --git a/src/njs_object.h b/src/njs_object.h
index 32e42936..b64f9947 100644
--- a/src/njs_object.h
+++ b/src/njs_object.h
@@ -110,6 +110,7 @@ njs_object_property_key_set(njs_lvlhsh_query_t *lhq, const njs_value_t *key,
     if (njs_is_symbol(key)) {
 
         lhq->key.length = 0;
+        lhq->key.start = NULL;
         lhq->key_hash = njs_symbol_key(key);
 
     } else {
diff --git a/src/njs_value.h b/src/njs_value.h
index 7865a013..6d0ebfa1 100644
--- a/src/njs_value.h
+++ b/src/njs_value.h
@@ -871,6 +871,7 @@ njs_set_object_value(njs_value_t *value, njs_object_value_t *object_value)
 #define njs_property_query_init(pq, _query, _own)                             \
     do {                                                                      \
         (pq)->lhq.key.length = 0;                                             \
+        (pq)->lhq.key.start = NULL;                                           \
         (pq)->lhq.value = NULL;                                               \
         (pq)->own_whiteout = NULL;                                            \
         (pq)->query = _query;                                                 \
diff --git a/src/test/njs_unit_test.c b/src/test/njs_unit_test.c
index d5826b75..37697386 100644
--- a/src/test/njs_unit_test.c
+++ b/src/test/njs_unit_test.c
@@ -10302,6 +10302,10 @@ static njs_unit_test_t  njs_test[] =
               "Object.getOwnPropertyDescriptor(o, Symbol.isConcatSpreadable).value"),
       njs_str("true") },
 
+    { njs_str("var o = {}, n = 5381 /* NJS_DJB_HASH_INIT */;"
+              "while(n--) o[Symbol()] = 'test'; o[''];"),
+      njs_str("undefined") },
+
     /* String */
 
     { njs_str("String()"),
-- 
2.47.3