libc: set close-on-exec for temp socket used to detect IPv6 support

kostikbel · kostikbel · commit eba403923626 · 2025-05-24T16:17:09.000+03:00
Reviewed by: markj Sponsored by: The FreeBSD Foundation MFC after: 1 week Differential revision: https://reviews.freebsd.org/D50509
diff --git a/lib/libc/gen/sysconf.c b/lib/libc/gen/sysconf.c
@@ -567,7 +567,7 @@ sysconf(int name)
 	case _SC_IPV6:
 #if _POSIX_IPV6 == 0
 		sverrno = errno;
-		value = _socket(PF_INET6, SOCK_DGRAM, 0);
+		value = _socket(PF_INET6, SOCK_CLOEXEC | SOCK_DGRAM, 0);
 		errno = sverrno;
 		if (value >= 0) {
 			_close(value);
