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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?rnAesRtGqJ0Gim/UbY16eBsX58SZePRawjKpuQLwAOUVnGs+RcrN8E3BzfNt?= =?us-ascii?Q?93kf5zxwMlZBUotfGfXsrZVYNYU/2u9Ii6fOQ6x9wRHRyqsSBXkBZyV4KXDH?= =?us-ascii?Q?kmy1Ybf9dAvBTyy73m99y3ayikHp6ba9q73iDRQCA+vQXmH94u5vvi9PmcUb?= =?us-ascii?Q?U3PX9JIzxHThUpmQIU3KQY3M8Tqp0LNafi81Yw7gw72GoPZv2k2znoLtnwiU?= =?us-ascii?Q?9Ik1l6jb3aBHZAyg+8RZGWNdPIETxSoQanLXbXzd+cKtDZbBep7WFAg/c0pJ?= =?us-ascii?Q?/xU1yILDI3FiZnYiry/Frdm8KahYiEu0uJPrJX1YOBh2XP6mIktaoAnqT6MI?= =?us-ascii?Q?2ALMxcxxpS56BUFQnsn5xkGt5UeVhrHnMDsws1iVBVmbkESu5NYT/zxJ50MJ?= =?us-ascii?Q?H76q7c2QHIRhzkDYS+kX0hnb6OrBqstL1pSRFTRPbAduoilgynadJcin6/27?= =?us-ascii?Q?EMVKkc1OhsZZi6+IiKlymOUwmtFG0QuHRhrmsc3nbR6/UQFlc6BZV30AELYK?= =?us-ascii?Q?s856Y6W2+4iTc9U4RorJrGJaLD9a8CRHAWChZFCmKSsyXnMzMXiZ2CL8XkOK?= =?us-ascii?Q?ovXccdcnPrafxQbgK43QAhoUpcaCbMewpRYNQkFwiEJ1O1yQ9pQwG0M/O01Q?= =?us-ascii?Q?SAVJwIiHDtxP9SNhqBx8yfTv77kK+lcv/zv8hQbZq81E8xcyz8jg/tWcGcV5?= =?us-ascii?Q?o7TTg79XK5xPf0XhmKsdeqH4NnqLxS51zYnAcodOYr81QqWMybbvRmLniUKd?= =?us-ascii?Q?HuS7PzE52cCiDzealBwzDIIzjeA9NxQUHXIlAN7JHJ2m+1CrTVF/67gaSYpy?= =?us-ascii?Q?7lC7Bpdyg6PrmC4RJbBWWPIqxyGV3Up7VdE/yBj8fu9NOJvfZH8lbdFhw6jo?= =?us-ascii?Q?6YYX4Qkkpz1Ds4AMvyGU9eIJsvr9V0Pbiy+SBixIDska88TYL8U3UeZzusoV?= =?us-ascii?Q?GYByBwxmdOxVjEIxUvePJt+8BrB1scPlB+XdZl8rthg2IMpBP0E6N9iuP3x7?= =?us-ascii?Q?+0PTLBB/qAmzOYQn5OaG8Wf36+Ov7RRQxghDgP3+lrulL2ysi8rJc0g9Ft2B?= =?us-ascii?Q?g6n/ESwB/vDttkK5UUIUSK4pXYs5PBTEjWAh77i1jx9gLM8MhKr1q+iiwDNT?= =?us-ascii?Q?f3aQ9+ez3xgJjT7H99hD/yZ6nw8DWJbSpIFi2w0nDAMkVJlau2Wo1pZerSK9?= =?us-ascii?Q?ARmOJta8wxBnB6p1nDLde+eBCV2xWTwCqDJhwWzZxqTuNz2CtJL0gDfdwX20?= =?us-ascii?Q?2GZIIM8bR6sE3G54FkvDmNcWJSvBFHDiopwH/WzaoNOmkchQTI1TKG+qUz+s?= =?us-ascii?Q?M4mFdAvpzxPYo5MODwDsoTndS/MHQI5/N9dmCCVEAGpUMHYvGk/7pzwKJYFf?= =?us-ascii?Q?5ZjjREOjkepsWBcd+Qwb+Lfq1sCMJgE5M2QQ/YKoX7YcERDm1sl02URPJeHW?= =?us-ascii?Q?yvtNmdG1fqweUaBtwl8tO8yAXczCY7PZcsEvYj0W4Ag32d5JhVL8IU7jwcyS?= =?us-ascii?Q?CX4g0N9Vbef+KsKJxiMR04yf8Gjc2DCKKCYskLuprY8YWnJO1tRfBUeRZ7zv?= =?us-ascii?Q?ywTFFxp9JkT158GLZ7oCl3OpOlvpUMx0ofWKjg4sYyOD+k/jCpBUdKwNeyy3?= =?us-ascii?Q?xS/pwyqL+Qt6XH+6Z6yQ0vC5EabTijmjagqXgFW5kuFae6s1VglOMCqS6kGd?= =?us-ascii?Q?ylPJWjDB+89vaoUW6GoUWPMeVd5AZjwNc8zn1Nzw5OgPTUC1?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: fdf25ded-66fd-4b1c-06f0-08df21e90030 X-MS-Exchange-CrossTenant-AuthSource: PH0PR12MB7957.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Oct 2026 07:27:52.5395 (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: 1AwTr2zy1NaHdV2pYD4KosRkxMl2PABuqsTTiYsl0LpXp2Ez2CB9WGRydO8GCc4vptSVyRFd9S/e9EGwxm/yXg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN0PR12MB5762 On Sat, Oct 03, 2026 at 04:23:39PM +0300, Anton Danilov wrote: > tun_get_user() is the only user of SKB_DROP_REASON_HDR_TRUNC. It sets > it when pskb_may_pull() fails to pull the Ethernet header of a frame > written to a TAP device. > > pskb_may_pull_reason() reports why the pull failed: PKT_TOO_SMALL if > the packet is shorter than requested, NOMEM if pulling the data into > the linear area fails. Use it for both header pulls in tun_get_user(), > on TAP and on TUN devices, and remove the now unused > SKB_DROP_REASON_HDR_TRUNC. The pull of the IP version byte on a TUN > device with IFF_NO_PI was reported as NOT_SPECIFIED and now reports > PKT_TOO_SMALL, for example when only the virtio-net header is written. > > After a successful pull drop_reason is SKB_NOT_DROPPED_YET. The later > error paths without a reason of their own, the unknown IP version on > TUN and the path that finds the queue detached, relied on the > SKB_DROP_REASON_NOT_SPECIFIED initializer. Fall back to > SKB_DROP_REASON_NOT_SPECIFIED at the free_skb label, as vxlan_rcv() > does, so that these paths, and any later one without a reason of its > own, keep reporting it. > > The errors returned to user space do not change. > > Suggested-by: Ido Schimmel > Link: https://lore.kernel.org/netdev/20260923145931.GA2859441@shredder/ > Assisted-by: LLM > Signed-off-by: Anton Danilov Reviewed-by: Ido Schimmel