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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?I+7sx4YNFEE5qT1ha317DpxQoebaMxk64Rt59zpUFQ+1Ugxdt2d7fSIDTiw3?= =?us-ascii?Q?stmtP/3jhTuzoqMslYcf8vONY4gTQ+I/UDOBAYFewyYzyYnzDzSoYeaqFVo8?= =?us-ascii?Q?gYH/zbNCfuHWv3LBGb8v2dqb32709gDYTw1lcpyxVWw/0IAkfezrOdAUoIXX?= =?us-ascii?Q?je0b1a8tn86naF21muRgkya/6lxnk0XayOWiuTm+OhiEIQU2Mac07qUUDmeg?= =?us-ascii?Q?+OuqY+WNax9P9Q4/ID7AmSyH7hB8ADWrvI+SSZiXvn/cbgarKKHPxdrxJaiQ?= =?us-ascii?Q?FYk1SRw8wCC/pVgv/pgjaC3k//gOtjMTgCkbJwz84nvQxqtCCuMnmEVk4e+e?= =?us-ascii?Q?dQZi9krhubUdM8MfdYbDIlGdWMD++MdS065N1d087lZ3JTOdK4LWoAI+VrVO?= =?us-ascii?Q?dpjvco9VDL3gzvwOAY9XYvCukPR4PpDS2N0qDKzlFYFVJdaIsKXDrctw6Vpx?= =?us-ascii?Q?4E7nRONYtTkC5R/+Kb4CpklzhrcGoCjrd7hKrV55m+07cDsc0GmCittvqUmO?= =?us-ascii?Q?lZU/JbTTYxaaAXv09Kbihghm1DVIFZnmEWcqoqSbKBa8xtt126AFOwZ7ykIj?= =?us-ascii?Q?GNj/LtX44DHPrgYEikHvuawiv3GWYDvIaj5SlpTpHUMITaus8RLj82LnHGrx?= =?us-ascii?Q?3KK4ejD+HS3GKNqJd8w+Cl+TeuwhEAjWjPnhAYqJxkls+21O37MNYZ3Dm4TP?= =?us-ascii?Q?u7kqslEMiCJYhomJ1kM2dv9VwcsU709KlUGkh2lYhVEwf/lZZOcIutv6DVKO?= =?us-ascii?Q?VOfHtP9lqz5PMKpLdMsFlM6l3GUHuPVNKt46uePJAlhkdhEMY2Gxsho++yNZ?= =?us-ascii?Q?e1CHd55WOzlOxi5qNn75j3/DlhLFrDCZSpjaaBsa0atLKkLpTSC7foTPNdPd?= =?us-ascii?Q?QUhN+cPTt0Db9oav4dmQeRoA6WkP2E5jZH240n580J5ECisjbOqN4ADLHBes?= =?us-ascii?Q?Mae71IHHOrwApuFmrskHIIEJEqixS4J5E5ZTaWvom2vgt7to8c0vFJ8ytO9f?= =?us-ascii?Q?FCAUYZ94cIXEecB7azN5TDB+EzCa8CKtQaOf2k7l3o/kafBnd/mkhcfvED24?= =?us-ascii?Q?POMCUpu0jEwiBob6MLl3moECFxnsTiJobCT54vIutjjw3OKQ1iZ/9RZEr0nL?= =?us-ascii?Q?5lg3iia+UPcEdJkYJaHPJMC5eMfLDEfYVSq48UPe/Zoi5vLR4A91pe+5rbM+?= =?us-ascii?Q?Wdd6LvFoodYplkCD3fDRVrAOR+3S56OlysZvPX7vEe0nPl+1muU6LP9i8+0y?= =?us-ascii?Q?9GJL3kh8N4yZWb6jEkX77iOGZ0xwL/Ky7PVVe2dfpU6Gdo706QnyjMA10PZd?= =?us-ascii?Q?R2mt40ZIR5gXy6mPFIUH+eXtROLhzL+QcI9vz/uYVNRtEzo4zT7dwmmykv0V?= =?us-ascii?Q?wvVv46Rx3eb4LUu70LLyO7282ZZI9Kco8N1j9CdhYUosVXjWZC7x/yBuyXIw?= =?us-ascii?Q?4ihyo2LK6xmmQOsrt8Sggp8pDTTvtgHlpJHvZS92j2YhcOucn1Snv8Ar7P3V?= =?us-ascii?Q?W4sVuIKJtT3JBh9BlA4TME88hG8LbvwvyQOfW6mWh8lHQ14bEXEixxHHQdED?= =?us-ascii?Q?xW/fysTDCUihr7OdAX9nl6cT2ZQW1AbdkWEYKyzok3MmEaQbeuc0s7hhUcQF?= =?us-ascii?Q?v2AuZjWswftg5pREe/s9i0q1m1g+sboUNLPLIQNDF92LLfGzlvOWwkwNX/kr?= =?us-ascii?Q?nzzcDHj+18Ttcugr2z3Ocuvh9zAVL4Zl0UTzjbEskgOmx3oG?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: b7d24e26-d1f2-42ef-9e19-08deebde3fa0 X-MS-Exchange-CrossTenant-AuthSource: SA3PR12MB7901.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 27 Jul 2026 12:54:51.7075 (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: TVHkJgA1v4cKVfLjevF4zD1ZjQJENlE1uyZhJkJ6aT9g4+L6rBPKfUJaI8srfoj6zKZNho3ZkTAo0QgGS1OHPQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA1PR12MB6067 On Mon, Jul 27, 2026 at 05:41:07PM +0800, Minhong He wrote: > When cancel_delayed_work() succeeds, MLD drops the work reference with > refcount_dec(). Unlike ma_put(), that does not free the ifmcaddr6 when > the count reaches zero. > > Use ma_put() on stop paths. On restart paths, re-arm the delayed work > before dropping the old reference, matching the ordering used for IPv4 > IGMP timer updates. > > Similar to commit 3546deaa0c30 ("ipv4: igmp: Fix potential memory leaks > in igmp_mod_timer() and igmp_stop_timer()"). In IPv4 the readers grab the multicast group from in_dev->mc_list using RCU so they could race with the removal of the group from the list. In IPv6, AFAICT, the readers iterate over the list using the idev->mc_lock mutex, so I don't see how the same race can happen there.