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Extend map_ptr before copying class table #9188

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Merged
merged 1 commit into from
Aug 1, 2022
Merged

Extend map_ptr before copying class table #9188

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1 change: 1 addition & 0 deletions Zend/zend_types.h
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Original file line number Diff line number Diff line change
Expand Up @@ -743,6 +743,7 @@ static zend_always_inline uint32_t zval_gc_info(uint32_t gc_type_info) {

#define ZSTR_SET_CE_CACHE_EX(s, ce, validate) do { \
if (!(validate) || ZSTR_VALID_CE_CACHE(s)) { \
ZEND_ASSERT((validate) || ZSTR_VALID_CE_CACHE(s)); \
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I didn't understand what do you do with this assertion

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It's asserting that the ce cache is valid, even if validation is skipped.

SET_CE_CACHE(GC_REFCOUNT(s), ce); \
} \
} while (0)
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46 changes: 46 additions & 0 deletions ext/opcache/tests/gh9164.phpt
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@@ -0,0 +1,46 @@
--TEST--
Bug GH-9164: Segfault in zend_accel_class_hash_copy
--EXTENSIONS--
opcache
pcntl
--INI--
opcache.enable_cli=1
--FILE--
<?php

$incfile = __DIR__.'/gh9164.inc';

// Generate enough classes so that the out of bound access will cause a crash
// without relying on assertion
$fd = fopen($incfile, 'w');
fwrite($fd, "<?php\n");
for ($i = 0; $i < 4096; $i++) {
fprintf($fd, "class FooBar%04d {}\n", $i);
}
fclose($fd);

// Ensure cacheability
touch($incfile, time() - 3600);

$pid = pcntl_fork();
if ($pid == 0) {
// Child: Declare classes to allocate CE cache slots.
require $incfile;
} else if ($pid > 0) {
pcntl_wait($status);
// Ensure that file has been cached. If not, this is testing nothing anymore.
if (!isset(opcache_get_status()['scripts'][$incfile])) {
print "File not cached\n";
}
// Populates local cache
require $incfile;
var_dump(new FooBar4095);
unlink($incfile);
} else {
echo "pcntl_fork() failed\n";
}

?>
--EXPECTF--
object(FooBar4095)#%d (0) {
}
22 changes: 11 additions & 11 deletions ext/opcache/zend_accelerator_util_funcs.c
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Expand Up @@ -347,15 +347,11 @@ zend_op_array* zend_accel_load_script(zend_persistent_script *persistent_script,
op_array = (zend_op_array *) emalloc(sizeof(zend_op_array));
*op_array = persistent_script->script.main_op_array;

if (zend_hash_num_elements(&persistent_script->script.function_table) > 0) {
zend_accel_function_hash_copy(CG(function_table), &persistent_script->script.function_table);
}

if (zend_hash_num_elements(&persistent_script->script.class_table) > 0) {
zend_accel_class_hash_copy(CG(class_table), &persistent_script->script.class_table);
}

if (EXPECTED(from_shared_memory)) {
if (ZCSG(map_ptr_last) > CG(map_ptr_last)) {
zend_map_ptr_extend(ZCSG(map_ptr_last));
}
Comment on lines 350 to +353
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This is just moving the if (EXPECTED(from_shared_memory)) { block to the beginning of the function, and the if (ZCSG(map_ptr_last) > CG(map_ptr_last)) { block at the beginning of the block.


/* Register __COMPILER_HALT_OFFSET__ constant */
if (persistent_script->compiler_halt_offset != 0 &&
persistent_script->script.filename) {
Expand All @@ -368,10 +364,14 @@ zend_op_array* zend_accel_load_script(zend_persistent_script *persistent_script,
}
zend_string_release_ex(name, 0);
}
}

if (ZCSG(map_ptr_last) > CG(map_ptr_last)) {
zend_map_ptr_extend(ZCSG(map_ptr_last));
}
if (zend_hash_num_elements(&persistent_script->script.function_table) > 0) {
zend_accel_function_hash_copy(CG(function_table), &persistent_script->script.function_table);
}

if (zend_hash_num_elements(&persistent_script->script.class_table) > 0) {
zend_accel_class_hash_copy(CG(class_table), &persistent_script->script.class_table);
}

if (persistent_script->num_early_bindings) {
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