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Message-ID: <a4019f0f9c8643a672a8df4858e85591725a2757.camel@kernel.org>
Subject: Re: [PATCH] NFSD: Fix trace_nfsd_fh_verify_err() crasher
From:   Jeff Layton <jlayton@kernel.org>
To:     Chuck Lever <chuck.lever@oracle.com>, linux-nfs@vger.kernel.org
Date:   Mon, 14 Nov 2022 06:35:40 -0500
In-Reply-To: <166828356768.42842.2412588018662481301.stgit@klimt.1015granger.net>
References: <166828356768.42842.2412588018662481301.stgit@klimt.1015granger.net>
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On Sat, 2022-11-12 at 15:06 -0500, Chuck Lever wrote:
> Now that the nfsd_fh_verify_err() tracepoint is always called on
> error, it needs to handle cases where the filehandle is not yet
> fully formed.
>=20
> Fixes: 93c128e709ae ("nfsd: ensure we always call fh_verify_error tracepo=
int")
> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
> ---
>  fs/nfsd/trace.h |    5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
>=20
> diff --git a/fs/nfsd/trace.h b/fs/nfsd/trace.h
> index ef01ecd3eec6..331a33a8f1f8 100644
> --- a/fs/nfsd/trace.h
> +++ b/fs/nfsd/trace.h
> @@ -254,7 +254,10 @@ TRACE_EVENT_CONDITION(nfsd_fh_verify_err,
>  				  rqstp->rq_xprt->xpt_remotelen);
>  		__entry->xid =3D be32_to_cpu(rqstp->rq_xid);
>  		__entry->fh_hash =3D knfsd_fh_hash(&fhp->fh_handle);
> -		__entry->inode =3D d_inode(fhp->fh_dentry);
> +		if (fhp->fh_dentry)
> +			__entry->inode =3D d_inode(fhp->fh_dentry);
> +		else
> +			__entry->inode =3D NULL;
>  		__entry->type =3D type;
>  		__entry->access =3D access;
>  		__entry->error =3D be32_to_cpu(error);
>=20

Doh!

Reviewed-by: Jeff Layton <jlayton@kernel.org>