Re: [4.10, panic, regression] iscsi: null pointer deref at iscsi_tcp_segment_done+0x20d/0x2e0

[Dave Chinner]

On Thu, Dec 22, 2016 at 07:18:27AM +0100, Christoph Hellwig wrote:
> On Wed, Dec 21, 2016 at 03:19:15PM -0800, Linus Torvalds wrote:
> > Looking around a bit, the only even halfway suspicious scatterlist
> > initialization thing I see is commit f9d03f96b988 ("block: improve
> > handling of the magic discard payload") which used to have a magic
> > hack wrt !bio->bi_vcnt, and that got removed. See __blk_bios_map_sg(),
> > now it does __blk_bvec_map_sg() instead.
> 
> But that check was only for discard (and discard-like) bios which
> had the maic single page that sometimes was unused attached.
> 
> For "normal" bios the for_each_segment loop iterates over bi_vcnt,
> so it will be ignored anyway.  That being said both I and the lists
> got CCed halfway through the thread and I haven't seen the original
> report, so I'm not really sure what's going on here anyway.

http://www.gossamer-threads.com/lists/linux/kernel/2587485

Cheers,

Dave.
-- 
Dave Chinner
david@xxxxxxxxxxxxx