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Fixed bug #81430 Check if runtime cache pointer is NULL before dereferencing #7665

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Fixed bug #81430 Check if runtime cache pointer is NULL before dereferencing #7665

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6e5ef72
Fixed bug #81430
rioderelfte Nov 18, 2021
a8aa2e4
Add failing test for dangling pointer access
rioderelfte Nov 25, 2021
1272778
Attempt to fix tests
cmb69 Dec 27, 2021
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1 change: 1 addition & 0 deletions Zend/zend_observer.c
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Original file line number Diff line number Diff line change
Expand Up @@ -229,6 +229,7 @@ ZEND_API void ZEND_FASTCALL zend_observer_fcall_end(
zend_execute_data *ex = execute_data->prev_execute_data;
while (ex && (!ex->func || ex->func->type == ZEND_INTERNAL_FUNCTION
|| !ZEND_OBSERVABLE_FN(ex->func->common.fn_flags)
|| !&RUN_TIME_CACHE(&ex->func->op_array)
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We thought alternatively to make sure the dummy execute_data created in call_attribute_constructor (ext/reflection/php_refleciton.c) should do what zend_get_call_trampoline_func does, but we didn't manage to replicate this:

ZEND_MAP_PTR_INIT(func->run_time_cache, (void***)&dummy);

|| !ZEND_OBSERVER_DATA(&ex->func->op_array)
|| ZEND_OBSERVER_DATA(&ex->func->op_array) == ZEND_OBSERVER_NOT_OBSERVED)) {
ex = ex->prev_execute_data;
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27 changes: 27 additions & 0 deletions ext/zend_test/tests/observer_bug81430_1.phpt
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@@ -0,0 +1,27 @@
--TEST--
Bug #81430 (Attribute instantiation frame has no run time cache)
--INI--
memory_limit=20M
zend_test.observer.enabled=1
zend_test.observer.observe_all=1
--FILE--
<?php

#[\Attribute]
class A {
public function __construct() {}
}

#[A]
function B() {}

$r = new \ReflectionFunction("B");
call_user_func([$r->getAttributes(A::class)[0], 'newInstance']);
?>
--EXPECTF--
<!-- init '%s' -->
<file '%s'>
<!-- init A::__construct() -->
<A::__construct>
</A::__construct>
</file '%s'>
33 changes: 33 additions & 0 deletions ext/zend_test/tests/observer_bug81430_2.phpt
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@@ -0,0 +1,33 @@
--TEST--
Bug #81430 (Attribute instantiation leaves dangling execute_data pointer)
--INI--
memory_limit=20M
zend_test.observer.enabled=1
zend_test.observer.observe_all=1
--XFAIL--
The stack allocated execute_data is invalid in zend_observer_fcall_end_all
--FILE--
<?php

#[\Attribute]
class A {
public function __construct() {
array_map("str_repeat", ["\xFF"], [100000000]); // cause a bailout
}
}

#[A]
function B() {}

$r = new \ReflectionFunction("B");
call_user_func([$r->getAttributes(A::class)[0], 'newInstance']);
?>
--EXPECTF--
<!-- init '%s' -->
<file '%s'>
<!-- init A::__construct() -->
<A::__construct>

Fatal error: Allowed memory size of %d bytes exhausted %s in %s on line %d
</A::__construct>
</file '%s'>