From d0ecc83ab5e250c4ddaf4b415c55e5b21957967e Mon Sep 17 00:00:00 2001
From: Nikita Popov <nikita.ppv@gmail.com>
Date: Wed, 17 Nov 2021 15:47:29 +0100
Subject: [PATCH 1/2] Assert hash is known when we claim it is

---
 Zend/zend_hash.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Zend/zend_hash.c b/Zend/zend_hash.c
index 8ee292106a6..5f878b2154b 100644
--- a/Zend/zend_hash.c
+++ b/Zend/zend_hash.c
@@ -646,6 +646,7 @@ static zend_always_inline Bucket *zend_hash_find_bucket(const HashTable *ht, zen
 
 	if (known_hash) {
 		h = ZSTR_H(key);
+		ZEND_ASSERT(h != 0 && "Hash must be known");
 	} else {
 		h = zend_string_hash_val(key);
 	}

From 6641e3b8f42795bd5955f59112c459435131d5ba Mon Sep 17 00:00:00 2001
From: Nikita Popov <nikita.ppv@gmail.com>
Date: Wed, 17 Nov 2021 15:53:25 +0100
Subject: [PATCH 2/2] Fix bug #81630: Don't claim known hash in
 getTraitAliases()

We don't intern this string, and this code is not particularly
performance critical in the first place, so just drop the the
assumption.
---
 NEWS                            |  2 ++
 ext/reflection/php_reflection.c | 15 ++++++---------
 2 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/NEWS b/NEWS
index 65d7d24ca40..7b98ac4c13c 100644
--- a/NEWS
+++ b/NEWS
@@ -9,6 +9,8 @@ PHP                                                                        NEWS
 - Reflection:
   . Fixed bug #81611 (ArgumentCountError when getting default value from
     ReflectionParameter with new). (Cameron Porter)
+  . Fixed bug #81630 (PHP 8.1: ReflectionClass->getTraitAliases() crashes with
+    Internal error). (Nikita)
 
 - XML:
   . Fixed bug #79971 (special character is breaking the path in xml function).
diff --git a/ext/reflection/php_reflection.c b/ext/reflection/php_reflection.c
index 11024b9aee8..2134d9aa72f 100644
--- a/ext/reflection/php_reflection.c
+++ b/ext/reflection/php_reflection.c
@@ -5116,18 +5116,15 @@ ZEND_METHOD(ReflectionClass, getTraitAliases)
 
 				if (!class_name) {
 					uint32_t j = 0;
-					zval *zv;
-					zend_class_entry *trait;
 					zend_string *lcname = zend_string_tolower(cur_ref->method_name);
 
 					for (j = 0; j < ce->num_traits; j++) {
-						zv = zend_hash_find_known_hash(CG(class_table), ce->trait_names[j].lc_name);
-						if (zv) {
-							trait = Z_CE_P(zv);
-							if (zend_hash_exists(&trait->function_table, lcname)) {
-								class_name = trait->name;
-								break;
-							}
+						zend_class_entry *trait =
+							zend_hash_find_ptr(CG(class_table), ce->trait_names[j].lc_name);
+						ZEND_ASSERT(trait && "Trait must exist");
+						if (zend_hash_exists(&trait->function_table, lcname)) {
+							class_name = trait->name;
+							break;
 						}
 					}
 					zend_string_release_ex(lcname, 0);