Michael,
----- Ursprüngliche Mail -----
> Von: "Greg Kroah-Hartman" <[email protected]>
> An: "Michael Walle" <[email protected]>
> CC: "linux-mtd" <[email protected]>, "linux-kernel"
> <[email protected]>, "Miquel Raynal"
> <[email protected]>, "richard" <[email protected]>, "Vignesh
> Raghavendra" <[email protected]>
> Gesendet: Mittwoch, 3. März 2021 17:08:56
> Betreff: Re: [PATCH] mtd: require write permissions for locking and badblock
> ioctls
> On Wed, Mar 03, 2021 at 04:57:35PM +0100, Michael Walle wrote:
>> MEMLOCK, MEMUNLOCK and OTPLOCK modify protection bits. Thus require
>> write permission. Depending on the hardware MEMLOCK might even be
>> write-once, e.g. for SPI-NOR flashes with their WP# tied to GND. OTPLOCK
>> is always write-once.
>>
>> MEMSETBADBLOCK modifies the bad block table.
>>
>> Fixes: f7e6b19bc764 ("mtd: properly check all write ioctls for permissions")
>> Signed-off-by: Michael Walle <[email protected]>
>> ---
>> drivers/mtd/mtdchar.c | 8 ++++----
>> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> Thanks for auditing the rest of these from my original patch. If this
> is ok with userspace tools, it's fine with me, but I don't even have
> this hardware to test with :)
That's my fear. Michael, did you verify?
In general you need to be root to open these device files.
So, I don't see a security problem here.
Thanks,
//richard
