[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-ID: <2b350e19.14e4.163f17c6d76.Coremail.00107082@163.com>
Date: Tue, 12 Jun 2018 08:54:13 +0800 (CST)
From: 王志强 <00107082@....com>
To: musl@...ts.openwall.com
Subject: musl dns search domain stop when current search got some error
Guys,
I have a alpine container running with following resolv conf:
# cat /etc/resolv.conf
nameserver 10.254.0.100
search default.svc.enn.cn svc.enn.cn default.pod.enn.cn pod.enn.cn enn.cn lan.davidkarlsen.com
options ndots:5
When I try to resolve some domain in the alpine container, say baidu.com, it would fail if some search search domain return code 0 without answers.
I think the cause is that name_from_dns would return error code, but name_from_dns_search would return whenever a error received from name_from_dns
I tried following code change, and it seems fix it
diff --git a/src/network/lookup_name.c b/src/network/lookup_name.c
index 209c20f..abb7da5 100644
--- a/src/network/lookup_name.c
+++ b/src/network/lookup_name.c
@@ -202,7 +202,7 @@ static int name_from_dns_search(struct address buf[static MAXADDRS], char canon[
memcpy(canon+l+1, p, z-p);
canon[z-p+1+l] = 0;
int cnt = name_from_dns(buf, canon, canon, family, &conf);
- if (cnt) return cnt;
+ if (cnt > 0 || cnt == EAI_AGAIN) return cnt;
}
}
DNS server would sometimes send back a response with return code 0 as following tcpdump shows, sometimes it would return SERVFAIL or REFUSED. (Not sure why though...)
00:36:13.165567 IP 10.254.0.100.domain > slave-2.55437: 2953 0/1/0 (106) 0x0000: 4500 0086 ab87 4000 3e11 bb6b 0afe 0064 E.....@.>..k...d
0x0010: ac10 1e02 0035 d88d 0072 a95c 0b89 8180 .....5...r.\....
0x0020: 0001 0000 0001 0000 0562 6169 6475 0363 .........baidu.c
0x0030: 6f6d 036c 616e 0c64 6176 6964 6b61 726c om.lan.davidkarl
0x0040: 7365 6e03 636f 6d00 001c 0001 c01a 0006 sen.com.........
0x0050: 0001 0000 0384 002e 036b 656e 026e 730a .........ken.ns.
0x0060: 636c 6f75 6466 6c61 7265 c027 0364 6e73 cloudflare.'.dns
0x0070: c043 78e1 741a 0000 2710 0000 0960 0009 .Cx.t...'....`..
0x0080: 3a80 0000 0e10 :.....
00:36:13.170095 IP 10.254.0.100.domain > slave-2.55437: 2637 0/1/0 (106)
0x0000: 4500 0086 ab88 4000 3e11 bb6a 0afe 0064 E.....@.>..j...d
0x0010: ac10 1e02 0035 d88d 0072 aab3 0a4d 8180 .....5...r...M..
0x0020: 0001 0000 0001 0000 0562 6169 6475 0363 .........baidu.c
0x0030: 6f6d 036c 616e 0c64 6176 6964 6b61 726c om.lan.davidkarl
0x0040: 7365 6e03 636f 6d00 0001 0001 c01a 0006 sen.com.........
0x0050: 0001 0000 0384 002e 036b 656e 026e 730a .........ken.ns.
0x0060: 636c 6f75 6466 6c61 7265 c027 0364 6e73 cloudflare.'.dns
0x0070: c043 78e1 741a 0000 2710 0000 0960 0009 .Cx.t...'....`..
Thanks
David
Content of type "text/html" skipped
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
