Re: [PATCH 9/9] sysfs: disallow world-writable files.

From: Gobinda Maji
Date: Fri May 01 2015 - 07:59:44 EST


On 30 April 2015 at 07:32, Rusty Russell <rusty@xxxxxxxxxxxxxxx> wrote:

> You're absolutely right, well spotted! The checks can be tightened. We
> don't really care about execute, but logically write is "more
> privileged" than read.
>
> Best to separate the tests; OTHER_WRITABLE <= GROUP_WRITABLE <= OWNER_WRITABLE
> and OTHER_READABLE <= GROUP_READABLE <= OWNER_READABLE.
>
> A patch would be welcome!

Thanks for the suggestion. OTHER_WRITABLE is already not permitted.
So, added the checks for GROUP_WRITABLE <= OWNER_WRITABLE for write
and OTHER_READABLE <= GROUP_READABLE <= OWNER_READABLE for read.

I am just sending a separate patch for this. The subject line will be
"[PATCH] sysfs: tightened sysfs permission checks"

--
Thanks,
Gobinda
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