Note: This is a beta release of Red Hat Bugzilla 5.0. The data contained within is a snapshot of the live data so any changes you make will not be reflected in the production Bugzilla. Also email is disabled so feel free to test any aspect of the site that you want. File any problems you find or give feedback here.
Bug 1518243 - GDB no longer dumps memory regions marked with the VM_DONTDUMP flag
Summary: GDB no longer dumps memory regions marked with the VM_DONTDUMP flag
Alias: None
Product: Red Hat Enterprise Linux 7
Classification: Red Hat
Component: gdb
Version: 7.4
Hardware: Unspecified
OS: Unspecified
Target Milestone: rc
: ---
Assignee: Jan Kratochvil
QA Contact: Michal Kolar
Vladimír Slávik
Depends On:
Blocks: 1524312
TreeView+ depends on / blocked
Reported: 2017-11-28 13:34 UTC by Sergio Lopez
Modified: 2018-04-10 10:26 UTC (History)
12 users (show)

Fixed In Version: gdb-7.6.1-108.el7
Doc Type: Bug Fix
Doc Text:
*GDB* can again dump memory protected by the "VM_DONTDUMP" flag Previous changes to the GNU Debugger *GDB* made the behavior of the "gcore" command more similar to the behavior of the Linux kernel when dumping process memory to increase data security. Consequently, users of *GDB* could not dump memory protected by the "VM_DONTDUMP" flag. The new "set dump-excluded-mappings" setting has been added to *GDB* to enable dumping of memory with this flag. As a result, users can dump the whole process memory with *GDB* again.
Clone Of:
: 1524312 (view as bug list)
Last Closed: 2018-04-10 10:25:07 UTC
Target Upstream Version:

Attachments (Terms of Use)

System ID Priority Status Summary Last Updated
Red Hat Product Errata RHBA-2018:0701 None None None 2018-04-10 10:26:20 UTC

Description Sergio Lopez 2017-11-28 13:34:12 UTC
Versions prior to gdb-7.6.1-83.el7, unconditionally included all memory regions when generating a dump file. Starting with this version, by default GDB will both inspect /proc/PID/coredump_filter, and unconditionally ignore memory regions marked with VM_DONTDUMP.

While it's possible requesting to GDB to ignore /proc/PID/coredump_filter by using the 'set use-coredump-filter' command, there's no way to request it to ignore the VM_DONTDUMP flag.

The change that altered the behavior is this one:

commit 38e1562bc360e0b89490b9b6903e1982a2f2f7fe
Author: Jan Kratochvil <>
Date:   Fri Nov 27 20:43:41 2015 +0100

    Support for /proc/PID/coredump_filter (Sergio Durigan Junior, RH
BZ 1265351).

    Sergio Durigan Junior, RH BZ 1265351


    - Resolves: rhbz#1265351

I've posted a tentative fix for this upstream:


Comment 10 Michal Kolar 2017-12-12 14:38:23 UTC
Reproduced against gdb-7.6.1-100.el7 and verified against gdb-7.6.1-108.el7.

Comment 17 errata-xmlrpc 2018-04-10 10:25:07 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.

Note You need to log in before you can comment on or make changes to this bug.