Re: [PATCH] drivers/scsi/qla2xxx: fix double free bug after firmware timeout

["Madhani, Himanshu" <Himanshu.Madhani@cavium.com>]

Hi Max, 

> On Jan 15, 2018, at 12:37 PM, Max Kellermann <mk@cm4all.com> wrote:
> 
> On 2018/01/15 20:58, "Madhani, Himanshu" <Himanshu.Madhani@cavium.com> wrote:
>> We have patch to prevent this double free in 4.16/scsi-queue
>> already.
> 
> No, let me repeat: this is a different bug!
> 
> Your bug is about the free call after waiting for completion
> synchronously in qla24xx_els_dcmd_iocb(), after it was already freed
> by qla2x00_sp_timeout().
> 
> My bug is about free in qla2x00_*_sp_done() and again in
> qla2x00_sp_timeout().  My patch description describes exactly that.
> 
> And you know what?  My patch fixes both bugs.  It is superior to the
> one that was merged 4 weeks later, isn't it?
> 
> You NACKed my patch 5 weeks ago, and I explained to you that you were
> talking about a different bug, but you never replied to that.
> 
> Max

Thanks for refreshing my memory. Sorry about not getting back to you earlier. 
I was out for couple weeks so it got dropped out of my bucket for response.

I do agree there is double free issue here. I’ll discuss this internally with folks who has 
deeper history of this code and will get back to you and see which approach we want to
take. 

Thanks,
- Himanshu