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charset="us-ascii" Content-ID: <67192B0E98E7004C9042A25ECEDAA685@namprd22.prod.outlook.com> Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: purdue.edu X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: SA1PR22MB3124.namprd22.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: 128277cd-664f-4b24-630f-08db6084a8e0 X-MS-Exchange-CrossTenant-originalarrivaltime: 29 May 2023 20:38:28.8235 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 4130bd39-7c53-419c-b1e5-8758d6d63f21 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: XJ/97Vb+sgD2Sl6X1TdZLYE2gODaUavZljRsmJv2fwkRbt03hiMJqX5gSU5hFsaEy0/2yyKkmXDEo+DISB6nNQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR22MB3498 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Hello, We found a data race that could happen between clone_mnt() and mnt_hold_writers() over mnt->mnt.mnt_flags. The two functions can write to mnt->mnt.mnt_flags concurrently. Although mnt_hold_writers() holds the lock_mount_hash(), clone_mnt() does n= ot respect this lock at this moment (it will apply for this lock later). Thread-1 Thread-2 // clone_mnt() // mnt_hold_writers() holding lock_mount_hash() mnt->mnt.mnt_flags &=3D ~(MNT_WRITE_HOLD|MNT_MARKED|MNT_INTERNAL); mnt->mnt.mnt_flags |=3D MNT_WRITE_HOLD; It is not clear whether this is a serious problem but we would like to repo= rt it just in case. Thanks, Sishuai=