MFC 287349,287404:

- Print sdl->sdl_data when sdl->sdl_nlen > 0 && sdl->sdl_alen == 0
  as link_ntoa(3) does.

- snprintf() returns at most size-1 of the chars printed into
  the buffer.  (n == hostlen) also means the buffer length was
  too short.

1 files changed, 15 insertions, 7 deletions

diff --git a/lib/libc/net/getnameinfo.c b/lib/libc/net/getnameinfo.c
index f766a8c..2b16b75 100644
--- a/lib/libc/net/getnameinfo.c
+++ b/lib/libc/net/getnameinfo.c
@@ -390,11 +390,22 @@ getnameinfo_link(const struct sockaddr *sa, socklen_t salen,
 
 	if (sdl->sdl_nlen == 0 && sdl->sdl_alen == 0 && sdl->sdl_slen == 0) {
 		n = snprintf(host, hostlen, "link#%d", sdl->sdl_index);
-		if (n > hostlen) {
+		if (n >= hostlen) {
 			*host = '\0';
-			return EAI_MEMORY;
+			return (EAI_MEMORY);
+		}
+		return (0);
+	}
+
+	if (sdl->sdl_nlen > 0 && sdl->sdl_alen == 0) {
+		n = sdl->sdl_nlen;
+		if (n >= hostlen) {
+			*host = '\0';
+			return (EAI_MEMORY);
 		}
-		return 0;
+		memcpy(host, sdl->sdl_data, sdl->sdl_nlen);
+		host[n] = '\0';
+		return (0);
 	}
 
 	switch (sdl->sdl_type) {
@@ -437,10 +448,7 @@ getnameinfo_link(const struct sockaddr *sa, socklen_t salen,
 }
 
 static int
-hexname(cp, len, host, hostlen)
-	const u_int8_t *cp;
-	char *host;
-	size_t len, hostlen;
+hexname(const u_int8_t *cp, size_t len, char *host, size_t hostlen)
 {
 	int i, n;
 	char *outp = host;