From:   Chuck Lever III <chuck.lever@oracle.com>
To:     Dai Ngo <dai.ngo@oracle.com>
CC:     Jeff Layton <jlayton@kernel.org>,
        Olga Kornievskaia <aglo@umich.edu>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>
Subject: Re: [PATCH 1/1] NFSD: fix leak referent count of
 nfsd4_ssc_umount_item in nfsd4_copy
Thread-Topic: [PATCH 1/1] NFSD: fix leak referent count of
 nfsd4_ssc_umount_item in nfsd4_copy
Thread-Index: AQHZL7WG8jsGDCk4gUeNJkqn2SORI66tycKA
Date:   Tue, 24 Jan 2023 16:54:57 +0000
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> On Jan 24, 2023, at 12:34 AM, Dai Ngo <dai.ngo@oracle.com> wrote:
>=20
> The reference count of nfsd4_ssc_umount_item is not decremented
> on error conditions. This prevents the laundromat from unmounting
> the vfsmount of the source file.
>=20
> This patch decrements the reference count of nfsd4_ssc_umount_item
> on error.
>=20
> Fixes: f4e44b393389 ("NFSD: delay unmount source's export after inter-ser=
ver copy completed.")
> Signed-off-by: Dai Ngo <dai.ngo@oracle.com>

Applied to nfsd-next, thanks!


> ---
> fs/nfsd/nfs4proc.c | 12 ++++++++----
> 1 file changed, 8 insertions(+), 4 deletions(-)
>=20
> diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
> index b4e7e18e1761..889b603619c3 100644
> --- a/fs/nfsd/nfs4proc.c
> +++ b/fs/nfsd/nfs4proc.c
> @@ -1821,13 +1821,17 @@ nfsd4_copy(struct svc_rqst *rqstp, struct nfsd4_c=
ompound_state *cstate,
> out:
> 	return status;
> out_err:
> +	if (nfsd4_ssc_is_inter(copy)) {
> +		/*
> +		 * Source's vfsmount of inter-copy will be unmounted
> +		 * by the laundromat. Use copy instead of async_copy
> +		 * since async_copy->ss_nsui might not be set yet.
> +	 	*/
> +		refcount_dec(&copy->ss_nsui->nsui_refcnt);
> +	}
> 	if (async_copy)
> 		cleanup_async_copy(async_copy);
> 	status =3D nfserrno(-ENOMEM);
> -	/*
> -	 * source's vfsmount of inter-copy will be unmounted
> -	 * by the laundromat
> -	 */
> 	goto out;
> }
>=20
> --=20
> 2.9.5
>=20

--
Chuck Lever