Re: [PATCH 1/2] scsi: sr: Fix sr_probe() missing mutex_destroy

[Bart Van Assche]

On 2020-05-30 09:41, James Bottomley wrote:
> On Sat, 2020-05-30 at 09:24 -0700, Bart Van Assche wrote:
>> On 2020-05-30 02:32, Simon Arlott wrote:
>>> If the device minor cannot be allocated or the cdrom fails to be
>>> registered then the mutex should be destroyed.
>>
>> Please add Fixes: and Cc: stable tags.
> 
> This isn't really a bug, is it?  mutex_destroy is a nop unless lock
> debugging is enabled in which case it checks the lock is unlocked and
> marks it as unusable to detect a use after destroy.  Since the
> structure containing the mutex is kfree'd in the next statement, kasan
> would also detect any use after free.  That's not to say we shouldn't
> do this to be fully correct ... just that it has no potential ever to
> have user visible impact so there doesn't seem to be much point
> cluttering up the stable process with it.

That makes sense to me. I may have confused Simon with my suggestion.

Bart.