lib/glibc
1
0
Fork 0
mirror of https://sourceware.org/git/glibc.git synced 2025-08-01 10:06:57 +03:00
Code Activity

resolv: Fix resolv_conf _res matching

Browse Source 
A dot-less host name without an /etc/resolv.conf file caused an
assertion failure in update_from_conf because the function would not
deal correctly with the empty search list case.

Thanks to Andreas Schwab for debugging assistence.
This commit is contained in:
Florian Weimer
2017-07-04 14:47:29 +02:00
parent f0107724c9
commit 4446a885f3
3 changed files with 61 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files

24
resolv/resolv_conf.c
View File

@ -272,7 +272,7 @@ resolv_conf_matches (const struct __res_state *resp,
nserv = MAXNS;
/* _ext.nscount is 0 until initialized by res_send.c. */
if (resp->nscount != nserv
&& (resp->_u._ext.nscount != 0 && resp->_u._ext.nscount != nserv))
|| (resp->_u._ext.nscount != 0 && resp->_u._ext.nscount != nserv))
return false;
for (size_t i = 0; i < nserv; ++i)
{
@ -295,9 +295,25 @@ resolv_conf_matches (const struct __res_state *resp,
/* Check that the search list in *RESP has not been modified by the
application. */
{
if (!(resp->dnsrch[0] == resp->defdname
&& resp->dnsrch[MAXDNSRCH] == NULL))
if (resp->dnsrch[0] == NULL)
{
/* Empty search list. No default domain name. */
return conf->search_list_size == 0 && resp->defdname[0] == '\0';
}
if (resp->dnsrch[0] != resp->defdname)
/* If the search list is not empty, it must start with the
default domain name. */
return false;
size_t nsearch;
for (nsearch = 0; nsearch < MAXDNSRCH; ++nsearch)
if (resp->dnsrch[nsearch] == NULL)
break;
if (nsearch > MAXDNSRCH)
/* Search list is not null-terminated. */
return false;
size_t search_list_size = 0;
for (size_t i = 0; i < conf->search_list_size; ++i)
{
@ -326,6 +342,8 @@ resolv_conf_matches (const struct __res_state *resp,
size_t nsort = conf->sort_list_size;
if (nsort > MAXRESOLVSORT)
nsort = MAXRESOLVSORT;
if (resp->nsort != nsort)
return false;
for (size_t i = 0; i < nsort; ++i)
if (resp->sort_list[i].addr.s_addr != conf->sort_list[i].addr.s_addr
|| resp->sort_list[i].mask != conf->sort_list[i].mask)