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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?hxFTGh2rAti9+z2oVUX+NITcYHnvTlixeob0mncPrRNa4KVH8NSt4ZRCI5bN?= =?us-ascii?Q?metUbX6wWOSMNrXYPnl5Xnr7MZEcMLxBtTakV+zAdR2vKQ2o6aEZO4u3bItJ?= =?us-ascii?Q?dVvVgjQlBN+V1SA1QNyYI6FGZo0xlbjd/g7Y/J2NSfMwX0hjiB05YbohlUlP?= =?us-ascii?Q?EIAO8JwI2Au4IX10SOXsWIUgANpIRSBGnypyQU0l1vm6aC5uvxaLbvf6fbeB?= =?us-ascii?Q?iY0MTmBM7WHYblXOkvDAnRD6YzTVKEwFAc70YRqZAtQpLrbglgM+jLinHGIC?= =?us-ascii?Q?7sAjZDNMAkxzPYU5R/wkoHvbbEZhuvaKj3T0Et5MfriHmK5TGY0ko7vxYe8N?= =?us-ascii?Q?QDFx2OPlHdOqUnf+OqoIaoX7Q6qTKu20zgNdwk6gJDtRpEKwh1pe6OTUqDaH?= =?us-ascii?Q?/oPV43PJDgkA7lQbKEBtEoFAMGY/AhDKw45wQHSHcmPQEkjskFFLkkdxSjv1?= =?us-ascii?Q?y6b5b92/hCPLh10bKhuH5pkijilMdyyXlIxClMzMz8zxRnQZretnQ5qSzzOW?= =?us-ascii?Q?dkSGhtV/VYqWClvIMAFhlKYAk0rvPe+H1p5GYPfSiYaVxFl6bRSpolH4nk/Y?= =?us-ascii?Q?lgvqWo8KyRFmvwO5VN/OrEMEqa9lDxkfatdRtviNP1g0V2O82TFANTSP7GIm?= =?us-ascii?Q?Pd4QT+gC3jXOXfUGv9hIv2J9ElveLq0o1lwy/l/CbnGK/HsC42MYm8JibpKH?= =?us-ascii?Q?snzOW3sylScaxruU5vTbpuw6OEGz4wlZPin7E/hqsafhOhNLDI79FvVUYzO5?= =?us-ascii?Q?lOX9qCkP/U+P0hGHqwmpc7pj6dxzX464mlLhErN8KFMLqpXY0BReCYuNLZgq?= =?us-ascii?Q?8mV0Z24yVWQTu/XQlRb+lgy2E6tCm14G0qRUHXhTt2/7f6vlfN5rgrbqKn36?= =?us-ascii?Q?fGbgoaeCkjTIqscHPzFUECPfLlqOY495gsRTsieZQfCeAj7MBlrMMy+Eg3fT?= =?us-ascii?Q?rVnFmTpPhrsi5LWwmrrn3uMqUvDH3G5O2noWVoFWI4GelPkv9pCLnNIz2OXu?= =?us-ascii?Q?sE33PbGIjtQG01Y5DwsbUcC5SqcHrvOOUNXy88woSAYq4IDh2B/Ofm1hUMNC?= =?us-ascii?Q?EcO4cCri9dOHM32rmZZMvRlJW5DfyYJg5OHb5Hq/zQ659kxKDus073avXrSy?= =?us-ascii?Q?KJ6l1/vJnO8IegzDyPvCiMoRPuJvlHva3GF2G/n/cERuRY9UrHiXUH9PJL92?= =?us-ascii?Q?nCwY+5YQQaf33EfgCPt9ydppY2Z39ZaPcevvOtwDX3HOaow6UBP0Af8pjaTJ?= =?us-ascii?Q?1hbgFE7U9ywDSx+jcBlWw5TyKDATxGiwkmNHmF744UD1SIJsvjW6yq5nmlnE?= =?us-ascii?Q?n725++KWlOueGbOx8yGzk6oXLrITBrOXorTMC5/yBwpaOHCpDrkWfxNi6luz?= =?us-ascii?Q?RrxqhUMJTWCCrp/VxVpODECdSsrnQv07BO7R+NCyh5CWXONqpZFKsh0cKk2P?= =?us-ascii?Q?Ev3TKNuv1O26dnRqYMpicChqZS0FrJZOErJwPIsDqXfVFiKdF6PUEsAwDexx?= =?us-ascii?Q?tdRDrUiZ3y2e/AragO7kMm3thbct3PdnZqOFPIu/yauEi6I5oWM7hjzDX+Ef?= =?us-ascii?Q?lwLVskXU7z5+RPeNW25ccFCq0BQqBThSBXSG4Zi5BjFONnE+NlEdhdPjmsIz?= =?us-ascii?Q?AO6uc+HCViPDy/2L2e7nlWekuygmfp8ahl7e7JrlcUXTnX3d1tlSXVk/qQaP?= =?us-ascii?Q?qMtuqjnhLoYCGcgQj+xhB6ASMvOA4p+blY7lkpBWXUFlqKB6?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: c2b29bdd-96f2-4b6a-9467-08df2d174ada X-MS-Exchange-CrossTenant-AuthSource: PH0PR12MB7957.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 18 Oct 2026 12:56:57.4536 (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: JIA7dAaKYjbJAY2Rd5aPUQFFO4Z9/l7T+oV8DFsc+n2nwcpQrQP/unxqo9WjH3FfpwGoVymze7Bdh6g+x5+6cg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ2PR12MB7962 On Sat, Oct 17, 2026 at 01:05:49PM +0200, Eric Dumazet wrote: > One remaining issue: for the synthetic skbs built by ipmr_get_route(), > pkt->cb holds NETLINK_CB, not IPCB. ipv4_pktinfo_prepare() still reads > it as IPCB: the iif comes from creds.pid, and IPCB(pkt)->flags > (l3mdev bit) from netlink_skb_parms. Whatever ends up in the > IP_PKTINFO cmsg for these reports is meaningless. > > These skbs are already identified by ip_hdr(skb)->version == 0, as > done in ipmr_cache_resolve() and ipmr_destroy_unres(), and they only > reach this point through the IGMPMSG_NOCACHE path. > > Could you skip pktinfo preparation for them in v6, and leave the > report control block zeroed? Something like: > > memset(skb->cb, 0, sizeof(skb->cb)); > > /* Route queries from ipmr_get_route() carry NETLINK_CB, not IPCB. */ > if (ip_hdr(pkt)->version) { > memcpy(pkt_cb, pkt->cb, sizeof(pkt_cb)); > ipv4_pktinfo_prepare(mroute_sk, pkt, false); > *PKTINFO_SKB_CB(skb) = *PKTINFO_SKB_CB(pkt); > memcpy(pkt->cb, pkt_cb, sizeof(pkt_cb)); > } Fine by me