From 6d70c08a2c37745df637b231711f6dec79dbc6e1 Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Wed, 2 Mar 2016 00:34:51 -0500 Subject: handle non-matching address family entries in hosts file name_from_hosts failed to account for the possibility of an address family error from name_from_numeric, wrongly counting such a return as success and using the uninitialized address data as part of the results passed up to the caller. non-matching address family entries cannot simply be ignored or results would be inconsistent with respect to whether AF_UNSPEC or a specific address family is queried. instead, record that a non-matching entry was seen, and fail the lookup with EAI_NONAME of no matching-family entries are found. --- src/network/lookup_name.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/src/network/lookup_name.c b/src/network/lookup_name.c index a26ad535..86f90ac1 100644 --- a/src/network/lookup_name.c +++ b/src/network/lookup_name.c @@ -49,7 +49,7 @@ static int name_from_hosts(struct address buf[static MAXADDRS], char canon[stati { char line[512]; size_t l = strlen(name); - int cnt = 0; + int cnt = 0, badfam = 0; unsigned char _buf[1032]; FILE _f, *f = __fopen_rb_ca("/etc/hosts", &_f, _buf, sizeof _buf); if (!f) switch (errno) { @@ -71,8 +71,16 @@ static int name_from_hosts(struct address buf[static MAXADDRS], char canon[stati /* Isolate IP address to parse */ for (p=line; *p && !isspace(*p); p++); *p++ = 0; - if (name_from_numeric(buf+cnt, line, family)) + switch (name_from_numeric(buf+cnt, line, family)) { + case 1: cnt++; + break; + case 0: + continue; + default: + badfam = EAI_NONAME; + continue; + } /* Extract first name as canonical name */ for (; *p && isspace(*p); p++); @@ -81,7 +89,7 @@ static int name_from_hosts(struct address buf[static MAXADDRS], char canon[stati if (is_valid_hostname(p)) memcpy(canon, p, z-p+1); } __fclose_ca(f); - return cnt; + return cnt ? cnt : badfam; } struct dpc_ctx { -- cgit v1.2.1