Received-SPF: pass (google.com: domain of linux-nfs-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Chuck Lever III <chuck.lever@oracle.com>
To:     Jeff Layton <jlayton@kernel.org>
CC:     Petr Vorel <pvorel@suse.cz>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>
Subject: Re: [PATCH v2] nfsd: fix net-namespace logic in
 __nfsd_file_cache_purge
Thread-Topic: [PATCH v2] nfsd: fix net-namespace logic in
 __nfsd_file_cache_purge
Thread-Index: AQHY7UBdjy7EMWQZjE+yKRdZMx04Ya4ovM+AgAAacgCAAACFgIAAACwA
Date:   Mon, 31 Oct 2022 18:47:28 +0000
Message-ID: <1E40B5C0-1E8A-4FBD-80FB-3432037F101D@oracle.com>
References: <20221031154921.500620-1-jlayton@kernel.org>
 <BCEEEF05-11E3-4E31-BDE1-DDCA65A5AB6F@oracle.com> <Y2AXrMEim07Y0LLY@pevik>
 <433f431a3684eb296a62f8f3cdbf34e185a5a84d.camel@kernel.org>
In-Reply-To: <433f431a3684eb296a62f8f3cdbf34e185a5a84d.camel@kernel.org>
Accept-Language: en-US
Content-Language: en-US
x-ms-exchange-antispam-messagedata-chunkcount: 1
x-ms-exchange-antispam-messagedata-0: =?us-ascii?Q?NcVn4aRQE67wCoknd11ADRbIUf+fa/eHz51XHK+CFCcsAgSqPFReOIUYSGr8?=
 =?us-ascii?Q?WwJ0fxCKyeODxC43kgDS4rHQjukiKdG4k4dWVIRERDuUvmlsjTdNuX3NDG+U?=
 =?us-ascii?Q?2O910N7IO+DQhxPV8z+/exY6K9f0St6X5wNYdKAB4QwjL0hgmurNCZq9L9BF?=
 =?us-ascii?Q?6Xq7S6pg8HcSAo6e0182bPE0oJUPwPgP4ewkiTYLHFjBlL0nzn0hjgfqTmbd?=
 =?us-ascii?Q?1EA2Z9EjtWOiAvmF1xi0iSjz5MicB4BzsCDGigBnKrrla0MuMIwWrXIuaylc?=
 =?us-ascii?Q?cyq5G1ZO5jQNks/9RTwjafuo81hy9LdRYMZUMCyMxpMiaektQiMKhrA5ORna?=
 =?us-ascii?Q?PHniJ3DSBN+qM5gAZWJNpGvSNBlAN079yuSYWBWJ1Q/LSOlLlB6OYBm9g3Z2?=
 =?us-ascii?Q?BedMN1DN0tV86+jdtHmoK3i6POfMfi+U6Bdpy0XVoLdtfoP17vbvJuDci7FN?=
 =?us-ascii?Q?kjogKP2uTU1efIeaXr0tVqErjhVGxOHqr0NI9r1kPgjZJR84cEqUaG0z0OGg?=
 =?us-ascii?Q?HZBl+wE5fR0Tog1e8ndGSTXp5SPWhhe0dEHtks2cW1J9gqHqieWkxsB9pVLm?=
 =?us-ascii?Q?fIcJJAo5rw+u6hIjIjn2sFAS6h5LyR5spvFl06wht002s/J9MnkhNeUgZKKJ?=
 =?us-ascii?Q?kGQbByd0VXxt6QLRgDb1aVtJzDErHJtw008a2Ni/HRiqOoiMQLIf2t64g3ZE?=
 =?us-ascii?Q?xSPdOvHPlHY7B7YNlswczj9RNoljXsOmmskC1eaZ8F7glL2NcHqBauvr8+j4?=
 =?us-ascii?Q?HOM0t3LaDhEMBP2solOE4clwphxm4pfut/87wn7NcMH/eKwnhM/tfOh/DEYY?=
 =?us-ascii?Q?msZ+rSvtuFojWjbG9C5UvFT+iMlhm9zE/O0jvMQpKYU0WTgSqXyt3V6D3A7J?=
 =?us-ascii?Q?8Z7rXxIYvx3Cpq+0EgP7Gd68VHkue4F0OR7QlBt9tM7NaUjGhF3FBMRPBLnb?=
 =?us-ascii?Q?X3giHyWb7PEzvmUClhIDdY/nthzKXb9S6n9U460X+QrrnsRuc4EFIq7IiGzI?=
 =?us-ascii?Q?bGCsZPq89+AGwwAWymxeND0jCsmpNKl6hKWmdZOwzfWlJe+rJoDPLLI5VGms?=
 =?us-ascii?Q?hdBRntJ8niNKL6kT4SECEvyD/JCxAHOn9xsLzNxk4oBpMyJE4O2B1LvJxCro?=
 =?us-ascii?Q?20OoYypml4IbJQvAZZbvYGX+S0jt4g7FKYHkLO4F9M20ijZb3F9aBFkLKDdY?=
 =?us-ascii?Q?D5lAlanCS0zkCQuxegP52BYCwo8cHrD+uTGouLTVW57rh8CmDrv86eiY+R/q?=
 =?us-ascii?Q?CQcLyiOow5iSJTq4kwZq2ifD43zYKIB5z6W/KR5YS/tbkYJn8M9KF/arOzJZ?=
 =?us-ascii?Q?8ve7a/FiUlaZPFTg+3x8gAyvEu+I/KSXCTQINf4o7jcw6yUP52lVmHmJ6fbV?=
 =?us-ascii?Q?RZDUfZdNJv5WsnK49egBaJGdX2wXomiqHbrISrf+CXDzDhhFLEJWvp/n6aGD?=
 =?us-ascii?Q?XwFR80wrxA/IuXBphWjta3xMBSE9VvJYiqlDMIkzZYi0pl2xraHyvlH0ojp4?=
 =?us-ascii?Q?HnEqY0UzCjX0Lr6deGIpBX9E66YPlv74mvJSieJlPDzXw7FWhZyb+nAHa/dI?=
 =?us-ascii?Q?qQQnp6MUDUCwmwY3yLVXKGsWuOZez9+atO491OeceNvxGu8UCj4sLl3VU5kk?=
 =?us-ascii?Q?iQ=3D=3D?=
Content-Type: text/plain; charset="us-ascii"
Content-ID: <01D44EB1384F764C8ECCDFD6255E96B9@namprd10.prod.outlook.com>
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
X-OriginatorOrg: oracle.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-AuthSource: BN0PR10MB5128.namprd10.prod.outlook.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 515e3ede-dd63-458d-e855-08dabb705c82
X-MS-Exchange-CrossTenant-originalarrivaltime: 31 Oct 2022 18:47:28.8848
 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b
X-MS-Exchange-CrossTenant-mailboxtype: HOSTED
X-MS-Exchange-CrossTenant-userprincipalname: OkEz4Xt3MqdwcTZspYe2lTSVXowDCsPyaVfnqX8QbgIrrHrCDRmmd7XLUzG0Jp4KYpG/g3VnyuGJP6b2sUvZ3A==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN0PR10MB5957
X-Proofpoint-Virus-Version: vendor=baseguard
 engine=ICAP:2.0.205,Aquarius:18.0.895,Hydra:6.0.545,FMLib:17.11.122.1
 definitions=2022-10-31_19,2022-10-31_01,2022-06-22_01
X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 adultscore=0 spamscore=0 bulkscore=0
 suspectscore=0 phishscore=0 malwarescore=0 mlxscore=0 mlxlogscore=999
 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2210170000
 definitions=main-2210310116
X-Proofpoint-ORIG-GUID: RdrG1x8fBrAVpI5wYl-C6GoILlqmq0gK
X-Proofpoint-GUID: RdrG1x8fBrAVpI5wYl-C6GoILlqmq0gK
X-Spam-Status: No, score=-2.8 required=5.0 tests=BAYES_00,DKIM_SIGNED,
        DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_LOW,
        RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE autolearn=ham
        autolearn_force=no version=3.4.6
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on
        lindbergh.monkeyblade.net
Precedence: bulk
List-ID: <linux-nfs.vger.kernel.org>
X-Mailing-List: linux-nfs@vger.kernel.org


> On Oct 31, 2022, at 2:46 PM, Jeff Layton <jlayton@kernel.org> wrote:
>=20
> On Mon, 2022-10-31 at 19:45 +0100, Petr Vorel wrote:
>>=20
>>>> On Oct 31, 2022, at 11:49 AM, Jeff Layton <jlayton@kernel.org> wrote:
>>=20
>>>> If the namespace doesn't match the one in "net", then we'll continue,
>>>> but that doesn't cause another rhashtable_walk_next call, so it will
>>>> loop infinitely.
>>=20
>>>> Fixes: ce502f81ba88 ("NFSD: Convert the filecache to use rhashtable")
>>>> Reported-by: Petr Vorel <pvorel@suse.cz>
>>>> Signed-off-by: Jeff Layton <jlayton@kernel.org>
>>>> ---
>>>> fs/nfsd/filecache.c | 5 ++---
>>>> 1 file changed, 2 insertions(+), 3 deletions(-)
>>=20
>>> Thank you! Applied and pushed to for-rc. I'll send a PR in a few days.
>>=20
>> Thanks for a quick action!
>>=20
>=20
> No problem.=20
>=20
>> What a shame you didn't put link to the report, which contains reproduce=
r.
>> https://lore.kernel.org/ltp/Y1%2FP8gDAcWC%2F+VR3@pevik/
>>=20
>> Kind regards,
>> Petr
>>=20
>=20
> Chuck, could you add that link to the changelog when you merge it?

In progress, I'll push the update in a moment.


>=20
> Thanks,
> Jeff
>=20
>>>> The v1 patch applies cleanly to v6.0, but not to Chuck's for-next
>>>> branch. This one should be suitable there.
>>>> diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c
>>>> index 98c6b5f51bc8..4a8aa7cd8354 100644
>>>> --- a/fs/nfsd/filecache.c
>>>> +++ b/fs/nfsd/filecache.c
>>>> @@ -890,9 +890,8 @@ __nfsd_file_cache_purge(struct net *net)
>>=20
>>>> 		nf =3D rhashtable_walk_next(&iter);
>>>> 		while (!IS_ERR_OR_NULL(nf)) {
>>>> -			if (net && nf->nf_net !=3D net)
>>>> -				continue;
>>>> -			nfsd_file_unhash_and_dispose(nf, &dispose);
>>>> +			if (!net || nf->nf_net =3D=3D net)
>>>> +				nfsd_file_unhash_and_dispose(nf, &dispose);
>>>> 			nf =3D rhashtable_walk_next(&iter);
>>>> 		}
>>=20
>>>> --=20
>>>> 2.38.1
>=20
> --=20
> Jeff Layton <jlayton@kernel.org>

--
Chuck Lever