Bug 1492780

Summary: samba4: Recompile without BIND_NOW due to IFUNC relocation issue on ppc64
Product: Red Hat Enterprise Linux 6 Reporter: Florian Weimer <fweimer>
Component: samba4Assignee: Andreas Schneider <asn>
Status: CLOSED ERRATA QA Contact: ipa-qe <ipa-qe>
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: 6.9CC: amore, asn, cbuissar, fweimer, jkurik, jrivera, ksiddiqu, lslebodn, mkosek, sbose, vanhoof
Target Milestone: rc   
Target Release: ---   
Hardware: ppc64   
OS: Unspecified   
Whiteboard:
Fixed In Version: samba4-4.2.10-13.el6 Doc Type: Bug Fix
Doc Text:
Cause: The samba4 packages were compiled in such a way that lazy binding during dynamic linking was disabled at run time. Consequence: On POWER, the IFUNC handler for the gettimeofday function in glibc would execute when glibc itself had not been relocated, leading to a crash when sssd_pac and other programs were started. Fix: The samba4 packages are again compiled without lazy binding. Result: The lazy relocation of the gettimeofday function is processed correctly and sssd_pac can start successfully on POWER.
Story Points: ---
Clone Of: Environment:
Last Closed: 2018-06-19 05:15:06 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Bug Depends On:    
Bug Blocks: 1374441, 1461138, 1504542    

Description Florian Weimer 2017-09-18 15:34:06 UTC
/usr/lib64/samba/libsamba-debug-samba4.so is linked with BIND_NOW and references gettimeofday, which has an IFUNC resolver on ppc64.  However, on Red Hat Enterprise Linux 6, glibc processes relocations in the wrong order, so when the IFUNC resolver runs, libc.so.6 has not yet been relocated.  As a result, there is a crash during relocation.  See bug 1398716 for details.

We cannot change the dynamic linker behavior at this point in the Red Hat Enterprise Linux 6 product life-cycle, so the only way to fix this issue is to recompile samba4 without BIND_NOW.

Comment 12 errata-xmlrpc 2018-06-19 05:15:06 UTC
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHSA-2018:1883