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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?smbacIt+kAJ0mRjqIEvgdKo2KTSMOtGF5vXcAon3tf2Iti66O0k0qzCgReK5?= =?us-ascii?Q?kGs35uQ/BFK8bi8bDTo99+A0jVNkIELSO8bjHNnCSBhHxz5QjtSh0yw2+7Z4?= =?us-ascii?Q?TyO21Bc0M4nzqGYPuhXsU58LjQCkQ7RuCoNtBYb5v8vsU/NbM/Ta5Q/wfuTv?= =?us-ascii?Q?J6yHrbyY2+GktwSFOT64UStEmtYcyVW22/cozfUw8NcZl4rt6fIXtZ+uQiBr?= =?us-ascii?Q?ikKlgPHQqXWlBBQfo5OIDYzA+lAjqLf0Fjxyqc1V7F23gbGCYWDph1WE1Wdz?= =?us-ascii?Q?SP72/wmtJlyhqUanhS69UEQ6TB8uSEtPYtrOS/aPrRLMgwKBa2t0y+6RdYAI?= =?us-ascii?Q?6qibN3rXpsvxICV6LlCdCHR2gPBWxq8GQzzq5ZWDP/J8IpVQI9UKl7nzRjUN?= =?us-ascii?Q?3EcQ8i33uR6qVSG2HoyMw4iZ0mNdzRtkWDvVHLnQqo6IOndNV9p0gAg1DCJb?= =?us-ascii?Q?3wtvFvKjgzCnMZ1sWcL1y9bt/a3lW02yjpPiPTDbw6pQGrSrmVr0UBBulU1A?= =?us-ascii?Q?cZetLn9AE1CsyDTF2FPEeSEeTA1S7zfGeYOJgkbkFyjYrmgwL85rLSFmQDTz?= =?us-ascii?Q?Zaww4dfbsCHo79pXomR58E7R8WkXwMUWEA8T4YxDSRmFB564VJN5LRO3G+k1?= =?us-ascii?Q?/9fU5LzWzZOm/G0GhG7MLxDjuvSE0hbv9MK5GjAR7zx8LdwVw2DWn6zaiVs1?= =?us-ascii?Q?CNNgGlIhyIedHo+qvulItjo7bngT1rymjR3oZepbFwsjgfb0JKc3eG3RXTLV?= =?us-ascii?Q?u+n6jhl3vXpeCY5KHClCvYxgvO8q3FwhoPpdrE36rw+pLbTzXohIz9ksTMms?= =?us-ascii?Q?UEgz84Q1G12d2dxeRJU/tAT2GBZOJCvkDiC8iTZnQLYMy5f+4PY53TRBLu7x?= =?us-ascii?Q?2f9yto7E+nXmCnCALFIo+mhiSbheSER0qYTooru9f5+o1DqeMANQ6lQvHy37?= =?us-ascii?Q?kifGyaFrLC3d8fhxjcAucagK3pPrPkgrN/aPmd5CNZCn1oKwttrHJeq55Fav?= =?us-ascii?Q?/ByVB6wc/FE2wze7so3xmwrNACTrxVDxeJaF99yHMlxP7nN555cg8G9EAero?= =?us-ascii?Q?0j5uJkry0X5UQh32/CBRYTigED1m02DGICdmpKGaVEdLkTljGTuFQuAY8Pk2?= =?us-ascii?Q?4+QgIIhvGFP75ux52f4S+U7owtPb2kYNZyl/Jlhs05NLdvawK5fHVOx5bRrU?= =?us-ascii?Q?kCTwF8p5PYsLcJ5EgDTRPPt9Yoe7WPUE/1yBwQWFkDM3XuDcX8Haf7EJFZLN?= =?us-ascii?Q?0wP7Bxy43iCZ+zBsCFvwr00se7Qs50ACfi3ZzZtzhgpRr3vtIUM8tKWOHCOR?= =?us-ascii?Q?F1FtkbqB39YjjybbVpBpKm3FI6YqdZC2ZpHq2B929+eSRj6+R360jwzkSzy0?= =?us-ascii?Q?n4Q0ZG0FQFNhc3m1xxycfhWLkTXMlAaQgBfNUkxQU7qL99hWzv7aVSemd4wb?= =?us-ascii?Q?38yAC4Ke8YkM/sJ3oseqNE7bVuGPNmOfeQyQe6w4LuWVChYUu077kkyqd0S8?= =?us-ascii?Q?UVFifHhatB446w/H5K7mRfQH+cjCEvgaru4kydFevR37QsUC77JvHfcxn5UL?= =?us-ascii?Q?Ds43cCW9galQ1rOkclKGR141c3IRcafvezqdXp+ObSpY281uE/axY4sFFC/C?= =?us-ascii?Q?BjoNGdQBroW7kA6H409xI4qEZLnn2QUmKmJQSlbbACUhglSZd3FmugwJCdgi?= =?us-ascii?Q?osNgFYKiE7QxDqg7q+ELWFCaRaD5vTKIGVwGgjsfB9Oi3y+k?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: c74499d7-72dd-4c2c-4918-08deba66424f X-MS-Exchange-CrossTenant-AuthSource: SA3PR12MB7901.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 May 2026 14:02:29.6239 (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: 1bc8JEUVMgGFLlsxBeWN2CzxYZLdgWo45kdbxVMXqHuoUtXL0zV3As5uilEmczHwq3eFsscSolNUxhvOIX4NiA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN7PPFD3499E3E3 On Mon, May 25, 2026 at 03:17:59PM +0800, Maoyi Xie wrote: > mlxsw_sp_fid_port_vid_list_add() inserts into a list sorted by > local_port. It walks the list to find the first entry with a > larger local_port, then inserts the new entry before it: > > list_add_tail(&port_vid->list, &tmp_port_vid->list); > > If the loop falls through (the new local_port is the largest), > tmp_port_vid runs off the end of the list. &tmp_port_vid->list > then ends up at the list head itself (container_of() offsets > cancel), and list_add_tail() inserts at the tail. So the code > works today. > > It is fragile though. Anyone who later adds a read of another > field of tmp_port_vid will hit memory outside the list head. > > Track the insertion point with a dedicated list_head pointer. > Initialise insert_before to &fid->port_vid_list, set it to > &tmp_port_vid->list only on early break, and pass insert_before > to list_add_tail(). The cursor is no longer touched after the > loop. Behaviour is unchanged. > > Same shape as the Koschel cleanups from 2022 (e.g. 99d8ae4ec8a > tracing, 2966a9918df clockevents, dc1acd5c946 dlm). > > Signed-off-by: Maoyi Xie Reviewed-by: Ido Schimmel