nwrap: Don't overflow the in_addr if convert IPv6.

Signed-off-by: Andreas Schneider <asn@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>

1 files changed, 22 insertions, 32 deletions

diff --git a/lib/nss_wrapper/nss_wrapper.c b/lib/nss_wrapper/nss_wrapper.c
index 57003bd612..931aaa5989 100644
--- a/lib/nss_wrapper/nss_wrapper.c
+++ b/lib/nss_wrapper/nss_wrapper.c
@@ -3854,13 +3854,18 @@ static int nwrap_getaddrinfo(const char *node,
 	struct addrinfo *p = NULL;
 	unsigned short port = 0;
 	struct hostent *he;
-	struct in_addr in;
-	bool is_addr_ipv4 = false;
-	bool is_addr_ipv6 = false;
+	struct {
+		int family;
+		union {
+			struct in_addr v4;
+#ifdef HAVE_IPV6
+			struct in6_addr v6;
+		} in;
+#endif
+	} addr;
 	int eai = EAI_SYSTEM;
 	int ret;
 	int rc;
-	int af;
 
 	if (node == NULL && service == NULL) {
 		return EAI_NONAME;
@@ -3912,32 +3917,25 @@ static int nwrap_getaddrinfo(const char *node,
 		}
 	}
 
-	af = hints->ai_family;
-	if (af == AF_UNSPEC) {
-		af = AF_INET;
+	rc = 0;
+	if (hints->ai_family == AF_UNSPEC || hints->ai_family == AF_INET) {
+		rc = inet_pton(AF_INET, node, &addr.in.v4);
 	}
-
-	rc = inet_pton(af, node, &in);
 	if (rc == 1) {
-		is_addr_ipv4 = true;
-		if (af == AF_UNSPEC) {
-			af = AF_INET;
-		}
+		addr.family = AF_INET;
 #ifdef HAVE_IPV6
 	} else {
-		struct in6_addr in6;
-
-		af = AF_INET6;
-
-		rc = inet_pton(af, node, &in6);
+		rc = inet_pton(AF_INET6, node, &addr.in.v6);
 		if (rc == 1) {
-			is_addr_ipv6 = true;
+			addr.family = AF_INET6;
 		}
 #endif
 	}
 
-	if (is_addr_ipv4) {
-		he = nwrap_files_gethostbyaddr(&in, sizeof(struct in_addr), af);
+	if (addr.family == AF_INET) {
+		he = nwrap_files_gethostbyaddr(&addr.in.v4,
+					       sizeof(struct in_addr),
+					       addr.family);
 		if (he != NULL) {
 			rc = nwrap_convert_he_ai(he, port, hints, &ai);
 		} else {
@@ -3945,18 +3943,10 @@ static int nwrap_getaddrinfo(const char *node,
 			rc = -1;
 		}
 #ifdef HAVE_IPV6
-	} else if (is_addr_ipv6) {
-		struct in6_addr in6;
-
-		rc =  inet_pton(af, node, &in6);
-		if (rc <= 0) {
-			eai = EAI_ADDRFAMILY;
-			return ret == 0 ? 0 : eai;
-		}
-
-		he = nwrap_files_gethostbyaddr(&in6,
+	} else if (addr.family == AF_INET6) {
+		he = nwrap_files_gethostbyaddr(&addr.in.v6,
 					       sizeof(struct in6_addr),
-					       af);
+					       addr.family);
 		if (he != NULL) {
 			rc = nwrap_convert_he_ai(he, port, hints, &ai);
 			eai = rc;