The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/overlays/chromiumos-overlay/+/94499290e515502e3379e0dc7cc0ba61e17b2f84

commit 94499290e515502e3379e0dc7cc0ba61e17b2f84
Author: Allen Webb <allenwebb@google.com>
Date: Tue Oct 02 20:23:01 2018

usbguard: Add madvise to seccomp policy.

A missing syscall was leading to crashes during cleanup of
"usbguard generate-policy".

BUG= chromium:891253 , b:117116656
TEST=/sbin/minijail0 -u usbguard -g usbguard -c 2 -l -p -n -e --uts \\
      --profile=minimalistic-mountns \\
      -b /sys,,1 \\
      -S /usr/share/policy/usbguard-daemon-seccomp.policy \\
      /usr/bin/usbguard generate-policy

Change-Id: I14c3767ca44b035adcc39d429e252c4e5a99f818
Signed-off-by: Allen Webb <allenwebb@google.com>
Reviewed-on: https://chromium-review.googlesource.com/1255848
Reviewed-by: Mattias Nissler <mnissler@chromium.org>

[modify] https://crrev.com/94499290e515502e3379e0dc7cc0ba61e17b2f84/sys-apps/usbguard/files/usbguard-daemon-seccomp-amd64.policy
[rename] https://crrev.com/94499290e515502e3379e0dc7cc0ba61e17b2f84/sys-apps/usbguard/usbguard-20180726-r11.ebuild
[modify] https://crrev.com/94499290e515502e3379e0dc7cc0ba61e17b2f84/sys-apps/usbguard/files/usbguard-daemon-seccomp-arm.policy

Issue 897569 has been merged into this issue.

Curious, why was this reported as fixed?  I see the following crash tagged to this bug:

https://crash.corp.google.com/browse?q=product_name%3D%27Chrome_ChromeOS%27+AND+expanded_custom_data.ChromeCrashProto.magic_signature_1.name%3D%27__libc_start_main%27+AND+product.Version%3D%2771.0.3578.21%27&stbtiq=&reportid=&index=0

kkaluri mistakenly marked 897569 as a duplicate of this issue. I have cleared that marking.

Issue 907169 has been merged into this issue.

Issue 915350 has been merged into this issue.

We might want to merge back to m-70 since this is a simple 1 line seccomp policy change and would take care of those crash reports. There isn't any functionality that is impacted by these crashes though because the feature is disabled.