Red Hat Bugzilla – Bug 848736
Segfaults in libresolv-2.15.so with hesiod
Last modified: 2016-11-24 10:48:59 EST
Created attachment 604877 [details]
Description of problem:
When using hesiod as the passwd/group database, some applications, most notably those of shadow-utils segfault in libresolv.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. I use dnsmasq configured like this (/etc/dnsmasq.conf):
server=<your usual DNS server>
2. Change nsswitch.conf to query hesiod for the group records -- change the group configuration so it looks like this:
group: files hesiod
3. Configure hesiod (/etc/hesiod.conf):
4. Configure resolver to query the local dnsmasq (/etc/resolv.conf):
5. useradd -M testuser
The new account is created
The /var/log/messages contain this error:
Aug 16 12:10:36 f-17 kernel: [ 4966.543583] useradd: segfault at 0 ip 00007fea08e72b34 sp 00007fff65bd6350 error 4 in libresolv-2.15.so[7fea08e69000+16000]
I have added a backtrace (in attachment).
I was not able to reproduce this bug on Rawhide. Also -- I'm not entirely sure this is a glibc problem but looking a the changes made in shadow-utils between F-17 and Rawhide makes glibc the main suspect.
Please let me know if you need some additional information.
Tomas, can you try the pending update (.56). This really looks like fallout from the broken "fixes" that were made to res_send and which were recently fixed (partially in .52, then fully in .55).
the .56 version really fixed the problem.
Thanks for verifying.