From: Guus Sliepen <guus@tinc-vpn.org>
Date: Sun, 12 Jul 2015 10:33:07 +0000 (+0200)
Subject: Fix undefined behaviour when left-shifting signed integers.
X-Git-Tag: release-1.1pre12~109
X-Git-Url: https://tinc-vpn.org/git/browse?p=tinc;a=commitdiff_plain;h=b396585383fe12c890ef7953efaa13a83963b5d7

Fix undefined behaviour when left-shifting signed integers.

Found by -fsanitize=undefined.
---

diff --git a/src/hash.c b/src/hash.c
index 91fc3d67..50934d9b 100644
--- a/src/hash.c
+++ b/src/hash.c
@@ -29,7 +29,7 @@ static uint32_t hash_function(const void *p, size_t len) {
 	uint32_t hash = 0;
 	while(true) {
 		for(int i = len > 4 ? 4 : len; --i;)
-			hash += q[len - i] << (8 * i);
+			hash += (uint32_t)q[len - i] << (8 * i);
 		hash *= 0x9e370001UL; // Golden ratio prime.
 		if(len <= 4)
 			break;