Re: blk: NULL ptr deref in blk_dequeue_request()

[Jiri Kosina]

On Wed, 17 Oct 2012, Jens Axboe wrote:

> >>>> 1. redo_fd_request() races with tear-down of the disks, but because
> >>>> set_next_request() checks disk->queue before doing anything this was
> >>>> usually harmless.  Now that do_floppy_init() doesn't clear disk->queue,
> >>>> the race condition is much easier to hit.  This may fix that problem in
> >>>> do_floppy_init(), though there appear to be worse bugs in tear-down
> >>>> order in floppy_module_exit():
> >> [...]
> >>>> 2. I made a big mistake in using the existing GENHD_FL_UP flag, as it is
> >>>> cleared by del_gendisk().  Incremental patch below, but it should be
> >>>> squashed into the previous patch if that branch is still rebase-able.
> >> [...]
> >>> I'm now seeing these instead:
> >> [...]
> >>
> >> Sorry, I'm not going to spend more time in the quagmire of the floppy
> >> driver.  Whoever has this commit in their tree, please revert or drop it
> >> as appropriate.
> > 
> > As far as I can tell, Jens has pulled it from me, but it hasn't made it 
> > into Linus' tree as of today.
> > 
> > I will do it in my tree and send a new pull request to Jens.
> 
> I did not add the patch from Ben, as it was reported as not working. My
> driver pull is late this time due to travel, but it'll go out start of
> next week. So if you have pending floppy updates that are tested at that
> time, then please do send them my way.

Sorry for the delay on my side as well. I am now working on reverting 
Ben's original patch and doing some testing. Will be sending you a pull 
request still tonight.

Thanks,

-- 
Jiri Kosina
SUSE Labs
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/