Fixed bug #69324 (Buffer Over-read in unserialize when parsing Phar)

4 files changed, 48 insertions, 36 deletions

diff --git a/ext/phar/phar.c b/ext/phar/phar.c
index ec82351410..bf0c985a7c 100644
--- a/ext/phar/phar.c
+++ b/ext/phar/phar.c
@@ -603,25 +603,18 @@ int phar_open_parsed_phar(char *fname, int fname_len, char *alias, int alias_len
  * 
  * data is the serialized zval
  */
-int phar_parse_metadata(char **buffer, zval **metadata, int zip_metadata_len TSRMLS_DC) /* {{{ */
+int phar_parse_metadata(char **buffer, zval **metadata, php_uint32 zip_metadata_len TSRMLS_DC) /* {{{ */
 {
 	const unsigned char *p;
-	php_uint32 buf_len;
 	php_unserialize_data_t var_hash;
 
-	if (!zip_metadata_len) {
-		PHAR_GET_32(*buffer, buf_len);
-	} else {
-		buf_len = zip_metadata_len;
-	}
-
-	if (buf_len) {
+	if (zip_metadata_len) {
 		ALLOC_ZVAL(*metadata);
 		INIT_ZVAL(**metadata);
 		p = (const unsigned char*) *buffer;
 		PHP_VAR_UNSERIALIZE_INIT(var_hash);
 
-		if (!php_var_unserialize(metadata, &p, p + buf_len, &var_hash TSRMLS_CC)) {
+		if (!php_var_unserialize(metadata, &p, p + zip_metadata_len, &var_hash TSRMLS_CC)) {
 			PHP_VAR_UNSERIALIZE_DESTROY(var_hash);
 			zval_ptr_dtor(metadata);
 			*metadata = NULL;
@@ -633,19 +626,14 @@ int phar_parse_metadata(char **buffer, zval **metadata, int zip_metadata_len TSR
 		if (PHAR_G(persist)) {
 			/* lazy init metadata */
 			zval_ptr_dtor(metadata);
-			*metadata = (zval *) pemalloc(buf_len, 1);
-			memcpy(*metadata, *buffer, buf_len);
-			*buffer += buf_len;
+			*metadata = (zval *) pemalloc(zip_metadata_len, 1);
+			memcpy(*metadata, *buffer, zip_metadata_len);
 			return SUCCESS;
 		}
 	} else {
 		*metadata = NULL;
 	}
 
-	if (!zip_metadata_len) {
-		*buffer += buf_len;
-	}
-
 	return SUCCESS;
 }
 /* }}}*/
@@ -666,6 +654,7 @@ static int phar_parse_pharfile(php_stream *fp, char *fname, int fname_len, char
 	phar_entry_info entry;
 	php_uint32 manifest_len, manifest_count, manifest_flags, manifest_index, tmp_len, sig_flags;
 	php_uint16 manifest_ver;
+	php_uint32 len;
 	long offset;
 	int sig_len, register_alias = 0, temp_alias = 0;
 	char *signature = NULL;
@@ -1031,16 +1020,21 @@ static int phar_parse_pharfile(php_stream *fp, char *fname, int fname_len, char
 	mydata->is_persistent = PHAR_G(persist);
 
 	/* check whether we have meta data, zero check works regardless of byte order */
+	PHAR_GET_32(buffer, len);
 	if (mydata->is_persistent) {
-		PHAR_GET_32(buffer, mydata->metadata_len);
-		if (phar_parse_metadata(&buffer, &mydata->metadata, mydata->metadata_len TSRMLS_CC) == FAILURE) {
-			MAPPHAR_FAIL("unable to read phar metadata in .phar file \"%s\"");
-		}
-	} else {
-		if (phar_parse_metadata(&buffer, &mydata->metadata, 0 TSRMLS_CC) == FAILURE) {
-			MAPPHAR_FAIL("unable to read phar metadata in .phar file \"%s\"");
+		mydata->metadata_len = len;
+		if(!len) {
+			/* FIXME: not sure why this is needed but removing it breaks tests */
+			PHAR_GET_32(buffer, len);
 		}
 	}
+	if(len > endbuffer - buffer) {
+		MAPPHAR_FAIL("internal corruption of phar \"%s\" (trying to read past buffer end)");
+	}
+	if (phar_parse_metadata(&buffer, &mydata->metadata, len TSRMLS_CC) == FAILURE) {
+		MAPPHAR_FAIL("unable to read phar metadata in .phar file \"%s\"");
+	}
+	buffer += len;
 
 	/* set up our manifest */
 	zend_hash_init(&mydata->manifest, manifest_count,
@@ -1075,7 +1069,7 @@ static int phar_parse_pharfile(php_stream *fp, char *fname, int fname_len, char
 			entry.manifest_pos = manifest_index;
 		}
 
-		if (buffer + entry.filename_len + 20 > endbuffer) {
+		if (entry.filename_len + 20 > endbuffer - buffer) {
 			MAPPHAR_FAIL("internal corruption of phar \"%s\" (truncated manifest entry)");
 		}
 
@@ -1111,19 +1105,20 @@ static int phar_parse_pharfile(php_stream *fp, char *fname, int fname_len, char
 			entry.flags |= PHAR_ENT_PERM_DEF_DIR;
 		}
 
+		PHAR_GET_32(buffer, len);
 		if (entry.is_persistent) {
-			PHAR_GET_32(buffer, entry.metadata_len);
-			if (!entry.metadata_len) buffer -= 4;
-			if (phar_parse_metadata(&buffer, &entry.metadata, entry.metadata_len TSRMLS_CC) == FAILURE) {
-				pefree(entry.filename, entry.is_persistent);
-				MAPPHAR_FAIL("unable to read file metadata in .phar file \"%s\"");
-			}
+			entry.metadata_len = len;
 		} else {
-			if (phar_parse_metadata(&buffer, &entry.metadata, 0 TSRMLS_CC) == FAILURE) {
-				pefree(entry.filename, entry.is_persistent);
-				MAPPHAR_FAIL("unable to read file metadata in .phar file \"%s\"");
-			}
+			entry.metadata_len = 0;
+		}
+		if (len > endbuffer - buffer) {
+			MAPPHAR_FAIL("internal corruption of phar \"%s\" (truncated manifest entry)");
+		}
+		if (phar_parse_metadata(&buffer, &entry.metadata, len TSRMLS_CC) == FAILURE) {
+			pefree(entry.filename, entry.is_persistent);
+			MAPPHAR_FAIL("unable to read file metadata in .phar file \"%s\"");
 		}
+		buffer += len;
 
 		entry.offset = entry.offset_abs = offset;
 		offset += entry.compressed_filesize;
diff --git a/ext/phar/phar_internal.h b/ext/phar/phar_internal.h
index c9306c15f4..fcfc86457d 100644
--- a/ext/phar/phar_internal.h
+++ b/ext/phar/phar_internal.h
@@ -654,7 +654,7 @@ int phar_mount_entry(phar_archive_data *phar, char *filename, int filename_len,
 char *phar_find_in_include_path(char *file, int file_len, phar_archive_data **pphar TSRMLS_DC);
 char *phar_fix_filepath(char *path, int *new_len, int use_cwd TSRMLS_DC);
 phar_entry_info * phar_open_jit(phar_archive_data *phar, phar_entry_info *entry, char **error TSRMLS_DC);
-int phar_parse_metadata(char **buffer, zval **metadata, int zip_metadata_len TSRMLS_DC);
+int phar_parse_metadata(char **buffer, zval **metadata, php_uint32 zip_metadata_len TSRMLS_DC);
 void destroy_phar_manifest_entry(void *pDest);
 int phar_seek_efp(phar_entry_info *entry, off_t offset, int whence, off_t position, int follow_links TSRMLS_DC);
 php_stream *phar_get_efp(phar_entry_info *entry, int follow_links TSRMLS_DC);
diff --git a/ext/phar/tests/bug69324.phar b/ext/phar/tests/bug69324.phar
new file mode 100644
index 0000000000..0882d88c22
--- /dev/null
+++ b/ext/phar/tests/bug69324.phar
diff --git a/ext/phar/tests/bug69324.phpt b/ext/phar/tests/bug69324.phpt
new file mode 100644
index 0000000000..70e3f972e7
--- /dev/null
+++ b/ext/phar/tests/bug69324.phpt
@@ -0,0 +1,17 @@
+--TEST--
+Bug #69324: Buffer Over-read in unserialize when parsing Phar
+--SKIPIF--
+<?php
+if (!extension_loaded("phar")) die("skip");
+?>
+--FILE--
+<?php
+try {
+$p = new Phar(dirname(__FILE__).'/bug69324.phar', 0);
+$meta=$p->getMetadata();
+var_dump($meta);
+} catch(Exception $e) {
+	echo $e->getMessage();
+}
+--EXPECTF--
+internal corruption of phar "%s" (truncated manifest entry)
\ No newline at end of file