Harden the page renderers

1 file changed, 7 insertions, 2 deletions

diff --git a/source/ui-clone.c b/source/ui-clone.c
index 4329e9d..2544e9f 100644
--- a/source/ui-clone.c
+++ b/source/ui-clone.c
@@ -72,6 +72,7 @@ static void print_pack_info(void)
 		// directly leaves those packs unfindable.
 		for (entry = packfile_store_get_packs(files->packed); entry; entry = entry->next) {
 			struct packed_git *pack = entry->pack;
+
 			if (pack->pack_local)
 				htmlf("P %s\n", last_path_component(pack->pack_name));
 		}
@@ -79,8 +80,7 @@ static void print_pack_info(void)
 }
 
 /*
- * Beyond the obvious directory traversal, the strict character set heads off
- * other funny business, for example the file name quirks of the Cygwin port.
+ * Only the characters an object path can hold pass, and no dotdot component.
  */
 static int path_is_safe(const char *path)
 {
@@ -112,6 +112,11 @@ static void send_file(const char *path)
 		}
 		return;
 	}
+	// fopen opens a directory on most systems and reads nothing from it.
+	if (!S_ISREG(st.st_mode)) {
+		cgit_print_error_page(404, "Not Found", "Not found");
+		return;
+	}
 	ctx.page.mimetype = "application/octet-stream";
 	// Offer the file under its path inside the repository, so the layout
 	// of the server's disk stays out of the download name.