rockchip-rk3588: Enable CONFIG_SECURITY_DMESG_RESTRICT kernel option

[alexl83]

Description

set CONFIG_SECURITY_DMESG_RESTRICT=y to BRANCH=edge & BRANCH=current
Now rebased to apply on CURRENT=6.10.5 and EDGE=6.11-rc3

Advised for KASLR-enabled kernels, complements nicely #7078 (without depending on each other) - no side effect for non-KASLR-enabled kernel/boards

Info from linuxsecurity.expert on this topic (added by @ColorfulRhino):

What does kernel.dmesg_restrict do?

The sysctl key kernel.dmesg_restrict can be used to configure the Linux kernel and restrict access to information from dmesg.

The kernel can be instructed to limit who can access the information provided by dmesg. Typically this is quick-win to disallow normal users from seeing sensitive data that is stored by dmesg like application crash details.

The kernel config option CONFIG_SECURITY_DMESG_RESTRICT is used to set the default value of this setting.
Values
0 - No restrictions
When dmesg_restrict is set to zero (0), there are no restrictions. This means all users can access information from dmesg.

1 - Restricted
Changing dmesg_restrict to one (1), will restrict access to those users that have the CAP_SYSLOG capability.

How Has This Been Tested?

• Built/ran orangepi5-plus edge (with patched u-boot from RFC: provide KASLR support to u-boot v2024.07 general availability #7078)

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• My changes generate no new warnings

[ColorfulRhino]

Same from comment #7080 (comment) also applies here :)

[ColorfulRhino]

Also for this one, let's wait until the 6.11 PR is merged since it will conflict otherwise and this change will get lost.

[ColorfulRhino]

I have updated the PR message to include some additional info for others to make it more easily understandable what this option does, without having to research it themselves.

[ColorfulRhino]

Let's wait and rebase after #7015 has been merged.

[igorpecovnik]

ok, lets move this in