lib/50195: Incorrect check in getnameinfo_link.

[henning.petersen%t-online.de@localhost]

>Number:         50195
>Category:       lib
>Synopsis:       Incorrect check in getnameinfo_link.
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    lib-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Sep 03 08:10:00 +0000 2015
>Originator:     Henning Petersen
>Release:        -current
>Organization:
>Environment:
>Description:
Incorrect check in getnameinfo_link.
Check is n > hostlen should be n >= hostlen.
>How-To-Repeat:

>Fix:
diff -u -p -r1.56 getnameinfo.c
--- lib/libc/net/getnameinfo.c	15 May 2015 14:26:02 -0000	1.56
+++ lib/libc/net/getnameinfo.c	3 Sep 2015 05:57:40 -0000
@@ -536,7 +535,7 @@ getnameinfo_link(const struct sockaddr *
 
 	if (sdl->sdl_nlen == 0 && sdl->sdl_alen == 0 && sdl->sdl_slen == 0) {
 		n = snprintf(host, hostlen, "link#%u", sdl->sdl_index);
-		if (n < 0 || (socklen_t) n > hostlen) {
+		if (n < 0 || (socklen_t) n >= hostlen) {
 			*host = '\0';
 			return EAI_MEMORY;
 		}