From 4458abf64172a62b92810c2293450106e6dfc763 Mon Sep 17 00:00:00 2001
From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: Tue, 24 Nov 2015 11:28:00 +0100
Subject: filter: avoid integer overflow in authenticate_post
ctx.env.content_length is an unsigned int, coming from the
CONTENT_LENGTH environment variable, which is parsed by strtoul. The
HTTP/1.1 spec says that "any Content-Length greater than or equal to
zero is a valid value." By storing this into an int, we potentially
overflow it, resulting in the following bounding check failing, leading
to a buffer overflow.
Reported-by: Erik Cabetas <Erik@cabetas.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
---
cgit.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/cgit.c b/cgit.c
index 5937b9e..05e5d57 100644
--- a/cgit.c
+++ b/cgit.c
@@ -651,7 +651,7 @@ static inline void open_auth_filter(const char *function)
static inline void authenticate_post(void)
{
char buffer[MAX_AUTHENTICATION_POST_BYTES];
- int len;
+ unsigned int len;
open_auth_filter("authenticate-post");
len = ctx.env.content_length;
--
cgit 1.4.1