Re: [PATCH net] net: nfc: llcp: Add lock when modifying device list

From: Simon Horman
Date: Mon Sep 11 2023 - 17:48:22 EST


On Mon, Sep 11, 2023 at 07:59:04AM +0200, Simon Horman wrote:
> On Sun, Sep 10, 2023 at 07:06:19PM -0400, Jeremy Cline wrote:
> > On Sun, Sep 10, 2023 at 05:28:12PM +0200, Simon Horman wrote:
> > > On Fri, Sep 08, 2023 at 07:58:53PM -0400, Jeremy Cline wrote:
> > > > The device list needs its associated lock held when modifying it, or the
> > > > list could become corrupted, as syzbot discovered.
> > > >
> > > > Reported-and-tested-by: syzbot+c1d0a03d305972dbbe14@xxxxxxxxxxxxxxxxxxxxxxxxx
> > > > Closes: https://syzkaller.appspot.com/bug?extid=c1d0a03d305972dbbe14
> > > > Signed-off-by: Jeremy Cline <jeremy@xxxxxxxxxx>
> > >
> > > Hi Jeremy,
> > >
> > > thanks for your patch.
> > >
> > > I don't think you need to resubmit for this,
> > > I think this patch warrants a fixes tag:
> > >
> > > Fixes: d646960f7986 ("NFC: Initial LLCP support")
> > >
> >
> > My bad, indeed. The lock in question looks to have been added in
> > 6709d4b7bc2e ("net: nfc: Fix use-after-free caused by
> > nfc_llcp_find_local") which itself includes a couple fix tags, should
> > this reference that commit instead as it won't backport without that
> > one?
>
> Yes, I think that is likely.
> Sorry for not noticing that.

And further, sorry for being vague in my previous email.
Having now looked over 6709d4b7bc2e I agree it is
the correct commit for a fixes tag for this patch.

>
> > > Otherwise, this looks good to me.
> > >
> > > Reviewed-by: Simon Horman <horms@xxxxxxxxxx>
> > >
> >
> > Thanks,
> > Jeremy
> >
>