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Description of problem:
After configuring krb5 authentication and winbind, attempts to sudo generate a segfault similar to:
May 30 17:28:17 hostname kernel: sudo[1629]: segfault at 0 ip 00007ffcabdc89eb sp 00007fff4af53790 error 4 in pam_winbind.so[7ffcabdc1000+e000]
Version-Release number of selected component (if applicable):
sudo-1.7.4p5-9.el6_2.x86_64
samba-winbind-clients-3.5.10-116.el6_2.x86_64
samba-winbind-3.5.10-116.el6_2.x86_64
krb5-workstation-1.9-22.el6_2.1.x86_64
pam_krb5-2.3.11-9.el6.x86_64
krb5-libs-1.9-22.el6_2.1.x86_64
How reproducible:
Configure krb + winbind, then attempt to sudo. Any user (including local-only) will cause sudo to segfault.
Steps to Reproduce:
1.yum install -y krb5-workstation sudo pam_krb5 samba-winbind
2.authconfig --enablekrb5 --krb5realm=MYDOMAIN.EDU --enablekrb5kdcdns --krb5adminserver=domain.admin.server.mine:749 --krb5kdc=kdc.server.mine:88 –update
3.authconfig --enablewinbind --enablewinbindauth --smbrealm=MYDOMAIN.EDU --enablewinbindusedefaultdomain --winbindtemplateshell=/bin/bash --smbsecurity ads --winbindtemplatehomedir=/home/%U --enablemkhomedir --smbworkgroup=MYDOMAIN --update
4. net ads join -U adminname
5. Log in as any non-root user (domain or local)
6. sudo something
Actual results:
Segfault, no sudo done
Expected results:
Sudo should not segfault
Additional info:
Willing to provide any additional backtrace/crash dump, but need instructions on how to generate.
Comment 2RHEL Program Management
2012-06-03 05:47:07 UTC
This request was not resolved in time for the current release.
Red Hat invites you to ask your support representative to
propose this request, if still desired, for consideration in
the next release of Red Hat Enterprise Linux.
Comment 7Nirupama Karandikar
2012-07-30 11:19:24 UTC
Comment 9RHEL Program Management
2012-12-14 08:40:56 UTC
This request was not resolved in time for the current release.
Red Hat invites you to ask your support representative to
propose this request, if still desired, for consideration in
the next release of Red Hat Enterprise Linux.
I cannot reproduce the problem with the recent build of sudo. I didn't test the previous version, so I'm not sure whether it segfaulted or not. Please re-test with the latest build in brew.
I don't think this is a problem in sudo as it doesn't do processing of the require_membership_of parameter. pam_winbind does it internally as is stated in the man page:
require_membership_of=[SID or NAME]
If this option is set, pam_winbind will only succeed if the user is
a member of the given SID or NAME. A SID can be either a group-SID,
an alias-SID or even an user-SID. It is also possible to give a
NAME instead of the SID. That name must have the form:
MYDOMAIN\\mygroup or MYDOMAIN\\myuser. pam_winbind will, in that
case, lookup the SID internally. Note that NAME may not contain any
spaces. It is thus recommended to only use SIDs. You can verify the
list of SIDs a user is a member of with wbinfo --user-sids=SID.
Please consider moving this bug to the samba (samba-winbind-clients) component if you see the segfault with the latest sudo too.
Thanks,
Dan K.
Comment 13RHEL Program Management
2013-10-14 04:57:05 UTC
This request was not resolved in time for the current release.
Red Hat invites you to ask your support representative to
propose this request, if still desired, for consideration in
the next release of Red Hat Enterprise Linux.