From b912e3e548c4879a015342be1910c12a629b8dd8 Mon Sep 17 00:00:00 2001
From: Shintaro Kawamura <kawasin@google.com>
Date: Thu, 21 Nov 2024 16:28:30 +0900
Subject: [PATCH] Fix permission of zram writeback and idle file

The default permission of "/sys/block/zram0/idle" and
"/sys/block/zram0/writeback" are "0200".

Adding read permission to the files does not make sense because reading
those files fail as EIO error.

We should keep permission as minimum as possible.

Bug: 117682284
Bug: 375432468
Test: ls -la /sys/block/zram0

Change-Id: I11ed5d9eee257002f4698edcd81de39d2c317ea1
---
 rootdir/init.rc | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/rootdir/init.rc b/rootdir/init.rc
index eeafd4c85..82844352a 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -1127,9 +1127,9 @@ on boot
 
     # System server manages zram writeback
     chown root system /sys/block/zram0/idle
-    chmod 0664 /sys/block/zram0/idle
+    chmod 0220 /sys/block/zram0/idle
     chown root system /sys/block/zram0/writeback
-    chmod 0664 /sys/block/zram0/writeback
+    chmod 0220 /sys/block/zram0/writeback
 
     # to access F2FS sysfs on dm-<num> directly
     mkdir /dev/sys/fs/by-name 0755 system system