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Fix GH-14506: Closing a userspace stream inside a userspace handler causes heap corruption #18797

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Fix GH-14506: Closing a userspace stream inside a userspace handler causes heap corruption #18797

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95 changes: 95 additions & 0 deletions ext/standard/tests/streams/gh14506.phpt
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Original file line number Diff line number Diff line change
@@ -0,0 +1,95 @@
--TEST--
GH-14506 (Closing a userspace stream inside a userspace handler causes heap corruption)
--FILE--
<?php

class Bomb {

public $context;

function stream_open($path, $mode, $options, &$opened_path): bool
{
return true;
}

function stream_write(string $data): int
{
global $readStream;
fclose($readStream);
return 0;
}

function stream_read(int $count): false|string|null
{
global $readStream;
fclose($readStream);
return "";
}

function stream_eof(): bool
{
global $readStream;
fclose($readStream);
return false;
}

function stream_seek(int $offset, int $whence): bool
{
global $readStream;
fclose($readStream);
return false;
}

function stream_cast(int $as)
{
global $readStream;
fclose($readStream);
return false;
}

function stream_flush(): bool
{
global $readStream;
fclose($readStream);
return false;
}
}

stream_register_wrapper('bomb', Bomb::class);
$readStream = fopen('bomb://1', 'r');
fread($readStream, 1);
fwrite($readStream, "x", 1);
fseek($readStream, 0, SEEK_SET);
$streams = [$readStream];
$empty = [];
try {
stream_select($streams, $streams,$empty, 0);
} catch (ValueError $e) {
echo $e->getMessage(), "\n";
}
fflush($readStream);
try {
fclose($readStream);
} catch (TypeError $e) {
echo $e->getMessage(), "\n";
}

?>
--EXPECTF--
Warning: fclose(): cannot close the provided stream, as it must not be manually closed in %s on line %d

Warning: fclose(): cannot close the provided stream, as it must not be manually closed in %s on line %d

Warning: fclose(): cannot close the provided stream, as it must not be manually closed in %s on line %d

Warning: fclose(): cannot close the provided stream, as it must not be manually closed in %s on line %d

Warning: fclose(): cannot close the provided stream, as it must not be manually closed in %s on line %d

Warning: stream_select(): Cannot represent a stream of type user-space as a select()able descriptor in %s on line %d

Warning: fclose(): cannot close the provided stream, as it must not be manually closed in %s on line %d

Warning: stream_select(): Cannot represent a stream of type user-space as a select()able descriptor in %s on line %d
No stream arrays were passed
fclose(): Argument #1 ($stream) must be an open stream resource
52 changes: 43 additions & 9 deletions main/streams/userspace.c
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Original file line number Diff line number Diff line change
Expand Up @@ -566,6 +566,9 @@ static ssize_t php_userstreamop_write(php_stream *stream, const char *buf, size_

ZVAL_STRINGL(&args[0], (char*)buf, count);

uint32_t orig_no_fclose = stream->flags & PHP_STREAM_FLAG_NO_FCLOSE;
stream->flags |= PHP_STREAM_FLAG_NO_FCLOSE;

zend_string *func_name = ZSTR_INIT_LITERAL(USERSTREAM_WRITE, false);
zend_result call_result = zend_call_method_if_exists(Z_OBJ(us->object), func_name, &retval, 1, args);
zend_string_release_ex(func_name, false);
Expand All @@ -575,6 +578,10 @@ static ssize_t php_userstreamop_write(php_stream *stream, const char *buf, size_
php_error_docref(NULL, E_WARNING, "%s::" USERSTREAM_WRITE " is not implemented!",
ZSTR_VAL(us->wrapper->ce->name));
}

stream->flags &= ~PHP_STREAM_FLAG_NO_FCLOSE;
stream->flags |= orig_no_fclose;

/* Exception occurred */
if (Z_ISUNDEF(retval)) {
return -1;
Expand Down Expand Up @@ -609,28 +616,31 @@ static ssize_t php_userstreamop_read(php_stream *stream, char *buf, size_t count

assert(us != NULL);

uint32_t orig_no_fclose = stream->flags & PHP_STREAM_FLAG_NO_FCLOSE;
stream->flags |= PHP_STREAM_FLAG_NO_FCLOSE;

ZVAL_LONG(&args[0], count);
zend_string *func_name = ZSTR_INIT_LITERAL(USERSTREAM_READ, false);
zend_result call_result = zend_call_method_if_exists(Z_OBJ(us->object), func_name, &retval, 1, args);
zend_string_release_ex(func_name, false);

if (UNEXPECTED(Z_ISUNDEF(retval))) {
return -1;
goto err;
}

if (UNEXPECTED(call_result == FAILURE)) {
php_error_docref(NULL, E_WARNING, "%s::" USERSTREAM_READ " is not implemented!",
ZSTR_VAL(us->wrapper->ce->name));
return -1;
goto err;
}

if (Z_TYPE(retval) == IS_FALSE) {
return -1;
goto err;
}

if (!try_convert_to_string(&retval)) {
zval_ptr_dtor(&retval);
return -1;
goto err;
}

didread = Z_STRLEN(retval);
Expand All @@ -657,19 +667,27 @@ static ssize_t php_userstreamop_read(php_stream *stream, char *buf, size_t count
"%s::" USERSTREAM_EOF " is not implemented! Assuming EOF",
ZSTR_VAL(us->wrapper->ce->name));
stream->eof = 1;
return -1;
goto err;
}
if (UNEXPECTED(Z_ISUNDEF(retval))) {
stream->eof = 1;
return -1;
goto err;
}

if (zval_is_true(&retval)) {
stream->eof = 1;
}
zval_ptr_dtor(&retval);

stream->flags &= ~PHP_STREAM_FLAG_NO_FCLOSE;
stream->flags |= orig_no_fclose;

return didread;

err:
stream->flags &= ~PHP_STREAM_FLAG_NO_FCLOSE;
stream->flags |= orig_no_fclose;
return -1;
}

static int php_userstreamop_close(php_stream *stream, int close_handle)
Expand Down Expand Up @@ -723,6 +741,9 @@ static int php_userstreamop_seek(php_stream *stream, zend_off_t offset, int when
ZVAL_LONG(&args[0], offset);
ZVAL_LONG(&args[1], whence);

uint32_t orig_no_fclose = stream->flags & PHP_STREAM_FLAG_NO_FCLOSE;
stream->flags |= PHP_STREAM_FLAG_NO_FCLOSE;

zend_string *func_name = ZSTR_INIT_LITERAL(USERSTREAM_SEEK, false);
zend_result call_result = zend_call_method_if_exists(Z_OBJ(us->object), func_name, &retval, 2, args);
zend_string_release_ex(func_name, false);
Expand All @@ -737,7 +758,8 @@ static int php_userstreamop_seek(php_stream *stream, zend_off_t offset, int when

zval_ptr_dtor(&retval);

return -1;
ret = -1;
goto out;
} else if (call_result == SUCCESS && Z_TYPE(retval) != IS_UNDEF && zval_is_true(&retval)) {
ret = 0;
} else {
Expand All @@ -748,7 +770,7 @@ static int php_userstreamop_seek(php_stream *stream, zend_off_t offset, int when
ZVAL_UNDEF(&retval);

if (ret) {
return ret;
goto out;
}

/* now determine where we are */
Expand All @@ -767,6 +789,11 @@ static int php_userstreamop_seek(php_stream *stream, zend_off_t offset, int when
}

zval_ptr_dtor(&retval);

out:
stream->flags &= ~PHP_STREAM_FLAG_NO_FCLOSE;
stream->flags |= orig_no_fclose;

return ret;
}

Expand Down Expand Up @@ -1394,6 +1421,9 @@ static int php_userstreamop_cast(php_stream *stream, int castas, void **retptr)
break;
}

uint32_t orig_no_fclose = stream->flags & PHP_STREAM_FLAG_NO_FCLOSE;
stream->flags |= PHP_STREAM_FLAG_NO_FCLOSE;

zend_string *func_name = ZSTR_INIT_LITERAL(USERSTREAM_CAST, false);
zend_result call_result = zend_call_method_if_exists(Z_OBJ(us->object), func_name, &retval, 1, args);
zend_string_release_ex(func_name, false);
Expand All @@ -1403,7 +1433,7 @@ static int php_userstreamop_cast(php_stream *stream, int castas, void **retptr)
php_error_docref(NULL, E_WARNING, "%s::" USERSTREAM_CAST " is not implemented!",
ZSTR_VAL(us->wrapper->ce->name));
}
return FAILURE;
goto out;
}

do {
Expand Down Expand Up @@ -1432,6 +1462,10 @@ static int php_userstreamop_cast(php_stream *stream, int castas, void **retptr)

zval_ptr_dtor(&retval);

out:
stream->flags &= ~PHP_STREAM_FLAG_NO_FCLOSE;
stream->flags |= orig_no_fclose;

return ret;
}

Expand Down