From: Kirill Isakov <is-kir@ya.ru>
Date: Sun, 15 Aug 2021 17:25:04 +0000 (+0600)
Subject: Fix UBSAN warnings about conversions and overflows.
X-Git-Url: https://tinc-vpn.org/git/browse?p=tinc;a=commitdiff_plain;h=04d8a8e34e1fe7f33f1946863b36a24ee358175f

Fix UBSAN warnings about conversions and overflows.
---

diff --git a/src/route.c b/src/route.c
index 26a8aabc..69d0ba74 100644
--- a/src/route.c
+++ b/src/route.c
@@ -485,7 +485,7 @@ static void clamp_mss(const node_t *source, const node_t *via, vpn_packet_t *pac
 		csum += csum >> 16;
 		csum ^= 0xffff;
 		DATA(packet)[start + 16] = csum >> 8;
-		DATA(packet)[start + 17] = csum;
+		DATA(packet)[start + 17] = csum & 0xff;
 		break;
 	}
 }
diff --git a/src/subnet.c b/src/subnet.c
index 602177ff..17dd39e8 100644
--- a/src/subnet.c
+++ b/src/subnet.c
@@ -83,7 +83,7 @@ static uint32_t hash_function_ipv6_t(const ipv6_t *p) {
 	uint32_t hash = hash_seed;
 
 	for(int i = 0; i < 4; i++) {
-		hash += fullwidth[i];
+		hash = wrapping_add32(hash, fullwidth[i]);
 		hash = wrapping_mul32(hash, 0x9e370001U);
 	}
 
@@ -95,7 +95,7 @@ static uint32_t hash_function_mac_t(const mac_t *p) {
 	uint32_t hash = hash_seed;
 
 	for(int i = 0; i < 3; i++) {
-		hash += halfwidth[i];
+		hash = wrapping_add32(hash, halfwidth[i]);
 		hash = wrapping_mul32(hash, 0x9e370001U);
 	}