|Summary:||multiple IP addresses in /etc/hosts (for one hostname) cause programs to access /etc/hosts via the usual library functions to segfault|
|Product:||[Retired] Red Hat Linux||Reporter:||Nils Philippsen <nphilipp>|
|Component:||glibc||Assignee:||Jakub Jelinek <jakub>|
|Status:||CLOSED ERRATA||QA Contact:|
|Version:||7.0||CC:||bugzilla, dr, pehr|
|Fixed In Version:||Doc Type:||Bug Fix|
|Doc Text:||Story Points:||---|
|Last Closed:||2000-10-05 00:00:05 UTC||Type:||---|
|oVirt Team:||---||RHEL 7.3 requirements from Atomic Host:|
Description Nils Philippsen 2000-09-25 18:52:28 UTC
If there are multiple interfaces on a host and each IP is assigned the same hostname, programs like pine, talk and others segfault as soon as they try to resolve hostnames.
Comment 1 Jakub Jelinek 2000-09-26 11:17:33 UTC
Do you have an example of such /etc/hosts? Does it segfault even if there is just eth0 and some IP aliases (e.g. eth0:1)?
Comment 2 adam.huffman 2000-09-26 12:53:43 UTC
I had a related problem, on a clean install /etc/hosts did not have a line for my eth0 address, but it did have the intended eth0 hostname and alias, on the same line as the loopback address i.e. 127.0.0.1 localhost.localdomain localhost my.lan.name my
Comment 3 Nils Philippsen 2000-09-26 14:56:27 UTC
The guilty /etc/hosts looked like this: --- 8< --- 127.0.0.1 localhost localhost.localdomain 126.96.36.199 rhlx03.fht-esslingen.de rhlx03 188.8.131.52 rhlx01.fht-esslingen.de rhlx01 nisserv rhlx01.rz.fht-esslingen.de www-stud www-stud.fht-esslingen.de 42 42.fht-esslingen.de 184.108.40.206 itppp0.it.fht-esslingen.de itppp0 220.127.116.11 rhlx01.fht-esslingen.de rhlx01 18.104.22.168 rhlx01.fht-esslingen.de rhlx01 22.214.171.124 rhlx01.fht-esslingen.de rhlx01 --- >8 --- But even stripped down versions like that: --- 8< --- 127.0.0.1 localhost 126.96.36.199 rhlx01.fht-esslingen.de rhlx01 188.8.131.52 rhlx01.fht-esslingen.de rhlx01 --- >8 --- caused programs like pine, talk, ... to crash. A few words on the setup on that machine: It's got an Acenic Gigabit Ethernet interface, using three VLANs on eth0 and multiple IPs in one VLAN (vlan2). The programs crash regardless of whether the (namewise) duplicate lines are in the same VLAN or in different ones.
Comment 4 Alan Cox 2000-10-02 16:47:50 UTC
*** Bug 18108 has been marked as a duplicate of this bug. ***
Comment 5 Jakub Jelinek 2000-10-03 10:58:43 UTC
Ouch, I cannot reproduce it, neither the case where there are different IPs, FQ hostname and hostname without domain (like above, one of the IPs is eth0 and one is eth0:1) nor duplicate lines in hosts (as #18108 speaks about) Can you please run the fauling programs under gdb and send me a backtrace (glibc comes with full debugging info so the backtrace should be readable). Thanks.
Comment 6 Nils Philippsen 2000-10-03 14:13:32 UTC
Hmmm, I cannot reproduce it here anymore, too. Sadly I cannot say which packages have been updated since it didn't work (I'm not the only person messing with this machine). We might as well blame this on some stray old packages which have been updated in the meantime.
Comment 7 Mike Bremford 2000-10-04 02:01:52 UTC
I've just upgraded my core system to Redhat 7.0 and I was getting this too. Here's the top of a stacktrace from sendmail, but I got identical traces from wget, ncftp (although not ftp!) and a bunch of others. #0 0x401c642b in __stpcpy () from /lib/libc.so.6 #1 0x4026e3e0 in _nss_files_gethostbyname_r (name=0x40036440 "tosh", result=0xbfffb7d0, buffer=0x8066220 "@(", buflen=1024, errnop=0x40261140, herrnop=0xbfffb8e8) at nss_files/files-hosts.c:262 #2 0x40231700 in __gethostbyname_r (name=0x40036440 "tosh", resbuf=0x402631a0, buffer=0x8066220 "@(", buflen=1024, result=0xbfffb8e0, h_errnop=0xbfffb8e8) at ../nss/getXXbyYY_r.c:191 #3 0x4022fa54 in gethostbyname (name=0x40036440 "tosh") at ../nss/getXXbyYY.c:127 I have upgraded glibc, glibc-devel, gcc, binutils, compat-glibc, bind, bind- utils amongst others to redhat 7.0 versions, others have not been changed. I installed the new wget too but was still getting the problem. On reading this bug report I modified my hosts file (see below) and commented out the lines beginning with 192 (not a huge problem since I'm running bind as well), and it started working. I have two network cards, hence the two subnets. Here's my original hosts file. 127.0.0.1 localhost 192.168.0.1 tosh.localnet tosh 192.168.1.1 tosh.localnet tosh 192.168.0.2 vaio.localnet vaio 192.168.1.2 aphrodite.localnet aphrodite 184.108.40.206 demon-gw Let me know if there's any more info I can supply to narrow this down. Cheers... Mike
Comment 8 Jakub Jelinek 2000-10-04 13:17:19 UTC
Actually, I think this bug could be related to #17019, I think I have fixed something like that on Sep, 2th. Can you guys who are able to reproduce it e.g. try ftp://ultra.linux.cz/private/glibc, which, altough quite old snapshot, should contain that fix?
Comment 9 Mike Bremford 2000-10-05 00:00:03 UTC
This does indeed fix the problem. I installed ftp://ultra.linux.cz/private/glibc/glibc-2.1.93-2.i386.rpm and it worked a treat.