Optional test for open() with empty path segments

CMakeLists.txt

@@ -51,6 +51,7 @@ OPTION(USE_STANDALONE_FUZZERS		"Enable standalone fuzzers (compatible with gcc)"
 OPTION(USE_LEAK_CHECKER			"Run tests with leak checker"				OFF)
 OPTION(DEBUG_POOL			"Enable debug pool allocator"				OFF)
 OPTION(DEBUG_STRICT_ALLOC		"Enable strict allocator behavior"			OFF)
+OPTION(DEBUG_STRICT_OPEN		"Enable path validation in open"			OFF)
 OPTION(ENABLE_WERROR			"Enable compilation with -Werror"			OFF)
 OPTION(USE_BUNDLED_ZLIB    		"Use the bundled version of zlib. Can be set to one of Bundled(ON)/Chromium. The Chromium option requires a x86_64 processor with SSE4.2 and CLMUL"			OFF)
    SET(USE_HTTP_PARSER			"" CACHE STRING "Specifies the HTTP Parser implementation; either system or builtin.")

src/CMakeLists.txt

@@ -11,6 +11,11 @@ IF(DEBUG_STRICT_ALLOC)
 ENDIF()
 ADD_FEATURE_INFO(debugalloc GIT_DEBUG_STRICT_ALLOC "debug strict allocators")
 
+IF(DEBUG_STRICT_OPEN)
+	SET(GIT_DEBUG_STRICT_OPEN 1)
+ENDIF()
+ADD_FEATURE_INFO(debugopen GIT_DEBUG_STRICT_OPEN "path validation in open")
+
 INCLUDE(PkgBuildConfig)
 INCLUDE(SanitizeBool)
 

src/features.h.in

@@ -3,6 +3,7 @@
 
 #cmakedefine GIT_DEBUG_POOL 1
 #cmakedefine GIT_DEBUG_STRICT_ALLOC 1
+#cmakedefine GIT_DEBUG_STRICT_OPEN 1
 
 #cmakedefine GIT_TRACE 1
 #cmakedefine GIT_THREADS 1

src/posix.c

@@ -109,6 +109,13 @@ int p_open(const char *path, volatile int flags, ...)
 {
 	mode_t mode = 0;
 
+	#ifdef GIT_DEBUG_STRICT_OPEN
+	if (strstr(path,"//") != NULL) {
+		errno = EACCES;
+		return -1;
+	}
+	#endif
+
 	if (flags & O_CREAT) {
 		va_list arg_list;
 

src/win32/posix_w32.c

@@ -543,6 +543,13 @@ int p_open(const char *path, int flags, ...)
 	mode_t mode = 0;
 	struct open_opts opts = {0};
 
+	#ifdef GIT_DEBUG_STRICT_OPEN
+	if (strstr(path,"//") != NULL) {
+		errno = EACCES;
+		return -1;
+	}
+	#endif
+
 	if (git_win32_path_from_utf8(wpath, path) < 0)
 		return -1;