Re: WARNING: refcount bug in sctp_wfree

From: Will Deacon
Date: Mon Mar 16 2020 - 11:51:32 EST


On Tue, Mar 10, 2020 at 09:01:18AM -0700, Kees Cook wrote:
> On Tue, Mar 10, 2020 at 02:39:01AM -0700, syzbot wrote:
> > syzbot has bisected this bug to:
> >
> > commit fb041bb7c0a918b95c6889fc965cdc4a75b4c0ca
> > Author: Will Deacon <will@xxxxxxxxxx>
> > Date: Thu Nov 21 11:59:00 2019 +0000
> >
> > locking/refcount: Consolidate implementations of refcount_t
>
> I suspect this is just bisecting to here because it made the refcount
> checks more strict?

Yes, this is the commit that enables full refcount checking for all
architectures unconditionally, so it's the canary in the coalmine rather
than the source of the problem.

Will