Bug 1492780 - samba4: Recompile without BIND_NOW due to IFUNC relocation issue on ppc64
Summary: samba4: Recompile without BIND_NOW due to IFUNC relocation issue on ppc64
Keywords:
Status: CLOSED ERRATA
Alias: None
Product: Red Hat Enterprise Linux 6
Classification: Red Hat
Component: samba4
Version: 6.9
Hardware: ppc64
OS: Unspecified
unspecified
unspecified
Target Milestone: rc
: ---
Assignee: Andreas Schneider
QA Contact: ipa-qe
URL:
Whiteboard:
Depends On:
Blocks: 1374441 1461138 1504542
TreeView+ depends on / blocked
 
Reported: 2017-09-18 15:34 UTC by Florian Weimer
Modified: 2021-09-09 12:36 UTC (History)
11 users (show)

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.
Clone Of:
Environment:
Last Closed: 2018-06-19 05:15:06 UTC
Target Upstream Version:

Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Bugzilla 1398716 0 high CLOSED glibc: ld.so relocation processing in forward dependency order breaks IFUNC resolvers 2021-09-09 12:00:48 UTC
Red Hat Product Errata RHSA-2018:1883 0 None None None 2018-06-19 05:16:14 UTC

Internal Links: 1398716

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
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