From: Rich Felker <dalias@aerifal.cx>
Date: Wed, 20 Feb 2019 22:58:21 +0000 (-0500)
Subject: fix spurious undefined behavior in getaddrinfo
X-Git-Tag: v1.1.22~57
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=ad795d56ba3fb9d69f524ee676e3b1e2355cceb7;p=oweals%2Fmusl.git

fix spurious undefined behavior in getaddrinfo

addressing &out[k].sa was arguably undefined, despite &out[k] being
defined the slot one past the end of an array, since the member access
.sa is intervening between the [] operator and the & operator.
---

diff --git a/src/network/getaddrinfo.c b/src/network/getaddrinfo.c
index 209970ad..efaab306 100644
--- a/src/network/getaddrinfo.c
+++ b/src/network/getaddrinfo.c
@@ -113,8 +113,8 @@ int getaddrinfo(const char *restrict host, const char *restrict serv, const stru
 				? sizeof(struct sockaddr_in)
 				: sizeof(struct sockaddr_in6),
 			.ai_addr = (void *)&out[k].sa,
-			.ai_canonname = outcanon,
-			.ai_next = &out[k+1].ai };
+			.ai_canonname = outcanon };
+		if (k) out[k-1].ai.ai_next = &out[k].ai;
 		switch (addrs[i].family) {
 		case AF_INET:
 			out[k].sa.sin.sin_family = AF_INET;
@@ -130,7 +130,6 @@ int getaddrinfo(const char *restrict host, const char *restrict serv, const stru
 		}
 	}
 	out[0].ref = nais;
-	out[nais-1].ai.ai_next = 0;
 	*res = &out->ai;
 	return 0;
 }