COMMON: Add proper error handling to the ZipArchive class

 - Add check in listMembers and skip files that can't be enumerated.
 - Add checks for all function calls in createReadStreamForMember (and no longer return a stream from an uninitialized buffer when the file cannot be read).

1 files changed, 25 insertions, 10 deletions

diff --git a/common/unzip.cpp b/common/unzip.cpp
index cd5d37f4bd..7b78da0faf 100644
--- a/common/unzip.cpp
+++ b/common/unzip.cpp
@@ -1470,11 +1470,13 @@ int ZipArchive::listMembers(Common::ArchiveMemberList &list) {
 
 	while (err == UNZ_OK) {
 		char szCurrentFileName[UNZ_MAXFILENAMEINZIP+1];
-		unzGetCurrentFileInfo(_zipFile, NULL,
-								szCurrentFileName, sizeof(szCurrentFileName)-1,
-								NULL, 0, NULL, 0);
-		list.push_back(ArchiveMemberList::value_type(new GenericArchiveMember(szCurrentFileName, this)));
-		matches++;
+		if (unzGetCurrentFileInfo(_zipFile, NULL,
+		                          szCurrentFileName, sizeof(szCurrentFileName)-1,
+		                          NULL, 0, NULL, 0) == UNZ_OK) {
+			list.push_back(ArchiveMemberList::value_type(new GenericArchiveMember(szCurrentFileName, this)));
+			matches++;
+		}
+
 		err = unzGoToNextFile(_zipFile);
 	}
 
@@ -1493,18 +1495,31 @@ Common::SeekableReadStream *ZipArchive::createReadStreamForMember(const Common::
 		return 0;
 
 	unz_file_info fileInfo;
-	unzOpenCurrentFile(_zipFile);
-	unzGetCurrentFileInfo(_zipFile, &fileInfo, NULL, 0, NULL, 0, NULL, 0);
+	if (unzOpenCurrentFile(_zipFile) != UNZ_OK)
+		return 0;
+
+	if (unzGetCurrentFileInfo(_zipFile, &fileInfo, NULL, 0, NULL, 0, NULL, 0) != UNZ_OK)
+		return 0;
+
 	byte *buffer = (byte *)malloc(fileInfo.uncompressed_size);
 	assert(buffer);
-	unzReadCurrentFile(_zipFile, buffer, fileInfo.uncompressed_size);
-	unzCloseCurrentFile(_zipFile);
+
+	if (unzReadCurrentFile(_zipFile, buffer, fileInfo.uncompressed_size) != (int)fileInfo.uncompressed_size) {
+		free(buffer);
+		return 0;
+	}
+
+	if (unzCloseCurrentFile(_zipFile) != UNZ_OK) {
+		free(buffer);
+		return 0;
+	}
+
 	return new Common::MemoryReadStream(buffer, fileInfo.uncompressed_size, DisposeAfterUse::YES);
 
 	// FIXME: instead of reading all into a memory stream, we could
 	// instead create a new ZipStream class. But then we have to be
 	// careful to handle the case where the client code opens multiple
-	// files in the archive and tries to use them indepenendtly.
+	// files in the archive and tries to use them independently.
 }
 
 Archive *makeZipArchive(const String &name) {