From 34e38a56b08ad20994ffc58ca2e54817c4a985f3 Mon Sep 17 00:00:00 2001 From: Hiroki Sato Date: Wed, 2 Sep 2015 16:50:49 +0000 Subject: [PATCH] - snprintf() returns at most size-1 of the chars printed into the buffer. (n == hostlen) also means the buffer length was too short. - Use sdl->sdl_data only when (sdl->sdl_nlen > 0 && sdl->sdl_alen == 0) to prevent redundant output. --- lib/libc/net/getnameinfo.c | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-) diff --git a/lib/libc/net/getnameinfo.c b/lib/libc/net/getnameinfo.c index ab5b8037459..f83d0e26a86 100644 --- a/lib/libc/net/getnameinfo.c +++ b/lib/libc/net/getnameinfo.c @@ -394,26 +394,22 @@ 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 (0); } - if (sdl->sdl_nlen > 0) { - if (sdl->sdl_nlen + 1 > hostlen) { + if (sdl->sdl_nlen > 0 && sdl->sdl_alen == 0) { + n = sdl->sdl_nlen; + if (n >= hostlen) { *host = '\0'; return (EAI_MEMORY); } memcpy(host, sdl->sdl_data, sdl->sdl_nlen); - n = sdl->sdl_nlen; - host += n; - if (sdl->sdl_alen > 0) { - *host++ = ':'; - n++; - } - hostlen -= n; + host[n] = '\0'; + return (0); } switch (sdl->sdl_type) {