CVE-2020-10781 kernel: zram sysfs resource consumption

                							

                <!--X-Body-Begin-->
<!--X-User-Header-->

oss-sec
mailing list archives
<!--X-User-Header-End-->
<!--X-TopPNI-->

By Date

By Thread

</form>

<!--X-TopPNI-End-->
<!--X-MsgBody-->
<!--X-Subject-Header-Begin-->
CVE-2020-10781 kernel: zram sysfs resource consumption

<!--X-Subject-Header-End-->
<!--X-Head-of-Message-->

From: Wade Mealing &lt;wmealing () redhat com&gt;

Date: Thu, 18 Jun 2020 11:19:35 +1000

<!--X-Head-of-Message-End-->
<!--X-Head-Body-Sep-Begin-->

<!--X-Head-Body-Sep-End-->
<!--X-Body-of-Message-->
Gday,

A user with a local account and the ability to read the
/sys/class/zram-control/hot_add file which on each read will create a
zram device node in the /dev/ directory.  This allocates kernel memory
and is not allocated to a user.

Continually reading this file may consume a large amount of system
memory and cause the system OOM killer to activate, terminating
userspace processes possibly making the system inoperable.

Acknowledgement:
Luca Bruno of Red Hat

Upstream discussion and patch
https://lore.kernel.org/linux-block/20200617103412.GA2027053 () kroah com/

Red Hat bugzilla:
https://bugzilla.redhat.com/show_bug.cgi?id=1847832

Thanks,

Wade Mealing

Product Security - Kernel
Red Hat

<!--X-Body-of-Message-End-->
<!--X-MsgBody-End-->
<!--X-Follow-Ups-->

<!--X-Follow-Ups-End-->
<!--X-References-->
<!--X-References-End-->
<!--X-BotPNI-->

By Date

By Thread

Current thread:

CVE-2020-10781 kernel: zram sysfs resource consumption Wade Mealing (Jun 17)

<!--X-BotPNI-End-->
<!--X-User-Footer-->
<!--X-User-Footer-End-->