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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?eDqUcSdw7CTn5hMtnvTA9jXE3hYWVesiIMJv6srkejknieaA9ybe1bPwWdRq?= =?us-ascii?Q?JHSCGhcipS6taA7ux0PgFGvFl51jSnr1OC+n2kUhpgrlR1IR15UaPkeEHVax?= =?us-ascii?Q?njKBc7oMm+w2G1zi0oCiGFURBA47DeYL0gPAPTFpeFZjpdUunBmYrqAyW1sS?= =?us-ascii?Q?EXGXJMs2lTp64WowJnLDqBeUg5OzlkNLA9I7yySFSLlS0Dvdq+0d4K/jMe/l?= =?us-ascii?Q?7At7sEzcvmYbw7IjkGAYfHThupqyChjgzXxABVz7Rwmsn3v//XD0EkpYeg60?= =?us-ascii?Q?bZNyer0nDjbKsiIf8re44neZ9iphBsgYO9b/YFQjwIUtJeyJZaJs9giPsu0Y?= =?us-ascii?Q?yWVPnrLvFc84gsOl7SiVFzTgtwQ/dbIU2CvcoF+dbGw2hcBooSEQtZxYCVjl?= =?us-ascii?Q?+IkGtpg/Wg+gIVNDqOX0LdX+JUYZjc8Eu+5ibjBLYR9vtNRfv2AB5HDW9baJ?= =?us-ascii?Q?xqNTAA3eVomJR7142FmGB8y3fe6It6bOCI3fHri34nSLM4Auf66jskWcIxJF?= =?us-ascii?Q?7IWmUAqTOpbPCQ1nm/kb2Pcw2NJmq8oZBqjBS6CdqMhnmWSpDOx43h6sAt1t?= =?us-ascii?Q?mpR6pgk1TF3i1bag4uF+TXe+1htsPNdVliaQBTnW4Pa+IV1QE8DrDDkMwUv7?= =?us-ascii?Q?MsDt1JKJA+5QVI5I1gtQPZ4RNbttxERjIFk17Yj6u6g1YR2QzIbmHq5DTN4V?= =?us-ascii?Q?mGH7HAdedCeqSO6AkVR3y5RkNkAaBB7whieUjRWbdrvRPSJZ0xeBx+XJNlUZ?= =?us-ascii?Q?cTR8drtDnfaAjU7b1Th404Pryea7Sli8xEB2JWrJ6887PS50fJm8uBW75Vwd?= =?us-ascii?Q?Ie7UxCO6tqKppWIH45U6uZfiNermI1xwUWC6IeWclYrmvBSUzIi+ryxjM0G8?= =?us-ascii?Q?I4YIPFlkrMs8uQTuTxmDi3EZo589AWRQzBn6SDJ2sOlwRyZlmHo3Vkb2Urhb?= =?us-ascii?Q?LYGYp110Ff1aNTfqyTnKHaKnO8mlOPVq2BQsYMpMUbHsmTr6ovLc3qkGr2k3?= =?us-ascii?Q?vy5mqECkct+8UQEmcPziAkjm13TzfpEsNNXQJO1FHao8cuc+oQOeQyh5fnUO?= =?us-ascii?Q?ydPjhTSOGbzFBwffTSOth7vdd1E+YYKIhdw+Se1xkdo0pP1wEzLaJa/FoSdx?= =?us-ascii?Q?t6XOsBdPfGutqpzLR+Nq0qyBWH3XYH3CCIr1EYn4ZCjMMjwZDQYs5I5I0zAo?= =?us-ascii?Q?H7VB4QKW0ubteTSHhh6+04VxF+a0cyBJ47BR/QozuPpR84gdmJ1Hu4T+4nzK?= =?us-ascii?Q?esMQJnZ8M7b7CTvoBDpRzik1Xk8FI/0aoTWQjQ5aSPwQv0kO3gKayhMuIuPT?= =?us-ascii?Q?CnQ/TQQr7s6A6DkVeY6VmwVX82jeeuLRKKM78eBy0fQwmuCm+3J9RHUGWapQ?= =?us-ascii?Q?M8r5CM29qx7mKzYSkO0JslAjjowdpZeJePSpy+mtzIUfW8rABlKHeQfZkP+t?= =?us-ascii?Q?oVc+v83hjqdRw9hgQuh8Ctt0iWbuON+WM3DPNJTkVjkDJZdb/3W6tLnGjb0N?= =?us-ascii?Q?3lt0w7YC/1Nj4d5fmU18zb/ePRkkNtLZrxl7YAtKbok8l4NgVujtz0bZQdt0?= =?us-ascii?Q?Hxw1Se2lARTZChqTvqcbME9NM3x+TXd3DYo9bEi+?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 2fca4c21-60f6-477b-b7c9-08db87a81cb4 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 18 Jul 2023 16:00:31.1196 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 4PRI2fiK+J0a2oyzIrrDxbgNqz+0i1pqA2EpH0zcQHJ03h2GpxxsTbstQ+/pe1Xb X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW4PR12MB7213 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 10, 2023 at 03:20:31PM -0700, Dmitry Torokhov wrote: > kvm_vfio_group_add() creates kvg instance, links it to kv->group_list, > and calls kvm_vfio_file_set_kvm() with kvg->file as an argument after > dropping kv->lock. If we race group addition and deletion calls, kvg > instance may get freed by the time we get around to calling > kvm_vfio_file_set_kvm(). > > Fix this by moving call to kvm_vfio_file_set_kvm() under the protection > of kv->lock. We already call it while holding the same lock when vfio > group is being deleted, so it should be safe here as well. > > Fixes: ba70a89f3c2a ("vfio: Change vfio_group_set_kvm() to vfio_file_set_kvm()") > Cc: stable@vger.kernel.org > Signed-off-by: Dmitry Torokhov > --- > virt/kvm/vfio.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) This looks correct, I don't know of any lock cylces that could form with kv->lock at least Reviewed-by: Jason Gunthorpe Jason