Re: Re: [PATCH 4.19.y 0/9] Fix the UAF issue caused by the loop driver

[Greg KH]

On Thu, Mar 07, 2024 at 10:34:12AM +0800, genjian zhang wrote:
> 
> At 2024-03-04 21:31:20, "Greg KH" <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> >On Fri, Mar 01, 2024 at 09:30:19AM +0800, Genjian wrote:
> >> From: Genjian Zhang <zhanggenjian@xxxxxxxxxx>
> >> 
> >> Hello!
> >> 
> >> We found that 2035c770bfdb ("loop: Check for overflow while configuring loop") lost a unlock loop_ctl_mutex in loop_get_status(...).
> >> which caused syzbot to report a UAF issue. However, the upstream patch does not have this issue.
> >> So, we revert this patch and directly apply the unmodified upstream patch.
> >> 
> >> Risk use-after-free as reported by syzbot：
> >
> >This looks good, but you are backporting commits that are NOT in newer
> >stable releases (i.e. from 5.8 but the commit is not in 5.4.y), is that
> >intentional?
> >
> >Does 5.4.y also have this problem?  If so, can you send a series that
> >fixes that up so I can take both of them at the same time?
> >
> >thanks,
> >
> >greg k-h
> 
> Thank you for your advice. This problem also exists in 5.4.y. 
> I will send a series of patches for 5.4.y.

All now queued up, thanks!

greg k-h