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/71587.diff Secret

Created Feb 15, 2016
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Patch for 71587
commit b1bd4119bcafab6f9a8f84d92cd65eec3afeface
Author: Stanislav Malyshev <stas@php.net>
Date: Sun Feb 14 22:34:39 2016 -0800
Fixed bug #71587 - Use-After-Free / Double-Free in WDDX Deserialize
diff --git a/ext/wddx/tests/bug71587.phpt b/ext/wddx/tests/bug71587.phpt
new file mode 100644
index 0000000..3fdfc35
--- /dev/null
+++ b/ext/wddx/tests/bug71587.phpt
@@ -0,0 +1,43 @@
+--TEST--
+Bug #71587 (Use-After-Free / Double-Free in WDDX Deserialize)
+--SKIPIF--
+<?php
+if (!extension_loaded("wddx")) print "skip";
+?>
+--FILE--
+<?php
+
+$xml = <<<EOF
+<?xml version='1.0' ?>
+<!DOCTYPE wddxPacket SYSTEM 'wddx_0100.dtd'>
+<wddxPacket version='1.0'>
+ <array>
+ <var name='ML'></var>
+ <string>manhluat</string>
+ <var name='ML2'></var>
+ <boolean value='a'/>
+ <boolean value='true'/>
+ </array>
+</wddxPacket>
+EOF;
+
+$wddx = wddx_deserialize($xml);
+var_dump($wddx);
+// Print mem leak
+foreach($wddx as $k=>$v)
+ printf("Key: %s\nValue: %s\n",bin2hex($k),bin2hex($v));
+
+?>
+DONE
+--EXPECTF--
+array(2) {
+ [0]=>
+ string(8) "manhluat"
+ [1]=>
+ bool(true)
+}
+Key: 30
+Value: 6d616e686c756174
+Key: 31
+Value: 31
+DONE
diff --git a/ext/wddx/wddx.c b/ext/wddx/wddx.c
index 7267ee1..da34246 100644
--- a/ext/wddx/wddx.c
+++ b/ext/wddx/wddx.c
@@ -936,6 +936,16 @@ static void php_wddx_pop_element(void *user_data, const XML_Char *name)
!strcmp(name, EL_DATETIME)) {
wddx_stack_top(stack, (void**)&ent1);
+ if (!ent1->data) {
+ if (stack->top > 1) {
+ stack->top--;
+ } else {
+ stack->done = 1;
+ }
+ efree(ent1);
+ return;
+ }
+
if (!strcmp(name, EL_BINARY)) {
int new_len=0;
unsigned char *new_str;
@@ -1032,6 +1042,7 @@ static void php_wddx_pop_element(void *user_data, const XML_Char *name)
}
} else if (!strcmp(name, EL_VAR) && stack->varname) {
efree(stack->varname);
+ stack->varname = NULL;
} else if (!strcmp(name, EL_FIELD)) {
st_entry *ent;
wddx_stack_top(stack, (void **)&ent);
@@ -1051,7 +1062,7 @@ static void php_wddx_process_data(void *user_data, const XML_Char *s, int len)
if (!wddx_stack_is_empty(stack) && !stack->done) {
wddx_stack_top(stack, (void**)&ent);
- switch (Z_TYPE_P(ent)) {
+ switch (ent->type) {
case ST_STRING:
if (Z_STRLEN_P(ent->data) == 0) {
STR_FREE(Z_STRVAL_P(ent->data));
@@ -1090,11 +1101,11 @@ static void php_wddx_process_data(void *user_data, const XML_Char *s, int len)
} else if (!strcmp(s, "false")) {
Z_LVAL_P(ent->data) = 0;
} else {
- stack->top--;
zval_ptr_dtor(&ent->data);
- if (ent->varname)
+ if (ent->varname) {
efree(ent->varname);
- efree(ent);
+ }
+ ent->data = NULL;
}
break;
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