Certain code paths used by the C library's memory allocator "fastbins" feature, enabled by default (mallopt option M_MXFAST set to non-zero), were not thread-safe. When the non-safe code paths executed they could cause corruption in the allocator that would lead to a program segfault. The thread-unsafe code paths have been made thread-safe and should no longer cause application segfaults.
Created attachment 820228[details]
Reproducer program
Description of problem:
Attached reproducer seem have a random issue of heap corruption.
Version-Release number of selected component (if applicable):
glibc-2.12-1.107.el6_4.4
How reproducible:
Always
Steps to Reproduce:
1. Compile and run the attached reproducer script under valgrind
Actual results:
data race condition and write conflicts
Expected results:
Should run without encountering race conditions
Additional info:
Upstream bugzilla for the same if reported at https://sourceware.org/bugzilla/show_bug.cgi?id=15073
Comment 1RHEL Program Management
2013-11-10 09:15:41 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.
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.
http://rhn.redhat.com/errata/RHSA-2014-1391.html