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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?onbgfxf4chE0EGuzKSFvaCJt4sA6ja3vvnWbWXB48GT6z4d7Rr3HR1Pzcx+o?= =?us-ascii?Q?WH9CgMEQAp/ROWlvysWGknH1u4pK/r3OeuR7Z2ixUToz6te+W6o74uqy36Kd?= =?us-ascii?Q?4JJ/fxIMdNPLymsJQgFPRubNSwmBp8dFVaVxxg0u76G48gVomrzvRfxpWfvM?= =?us-ascii?Q?8oTro4c6Z7RCXql/9by03qvFv6kF6C3Iqk8I6UkCdX52Fe955iwd1zdhfJcl?= =?us-ascii?Q?gcB4c1rcJT0+aZf5jXhAoTxbVaZyaZlXKrkQW8LFCUZVvNjmmQQ4by+NNIih?= =?us-ascii?Q?eX7nZ180K8sUlVp3fjfDuuQNzRu1b9AGPvEGS8Dt5IfRaQqdShKSOjeAnM4b?= =?us-ascii?Q?qliwo0vxd5PMPfsJ2V+y6xry6ekEZrOCMuVluCyGv+Sst33LPipkt7IVEFbC?= =?us-ascii?Q?od8JIlyPbGwwAoe4ZQXKgNhSmQBSHAMktDMDOyOrqyC8PlNq0Q/+AStalJ/+?= =?us-ascii?Q?O4/0p2LbYIh2rMZoEOn5tWzHZKI8/pFEST5Me8Q+NX9Dv9EfRl3Bko2mN1Xi?= =?us-ascii?Q?h37WLWCOL4q4/rxnrG3Rv8Q7HW4lKunH8Dy2v1Ro4tOUjicFflOJ/Yn59EKs?= =?us-ascii?Q?vk42tuc9RN1VqwpoYmxXGEGRnFSnjo9zV/wFGE/ZufL8WaazyFbb4yaCz/Jq?= =?us-ascii?Q?VRdXWmn5rj03eSHFnpqRrT0dvufqugel2o/Zim31MWN5cboczoRC2DuRvrCT?= =?us-ascii?Q?DcquDMuGjQAySbG6NbyX414zed5p2VOBjhVjxB8pzCc/FObkpq7dMcs3uXRS?= =?us-ascii?Q?EuHhFvHQ1nBmutJ0IpzTThLJcwA3ReDHomW8kyYBnF7zDcUR0dYtTakxI7SL?= =?us-ascii?Q?4VVitzPpECq5AKNO9kcebPU0ZsOT7LIkJFxYRRhzvb5T8UoZTSDHmzSSlfed?= =?us-ascii?Q?CNf/aHYQgbvHqvV2g3zTOuyXS0b0R0tcbPTvoHbsKl9sc5eR3BlO3x2b72Rk?= =?us-ascii?Q?wuLGVjDF/T+GaurNpsmxNLn1J6IVzgo4tm3km4LqcjfIkipNFQ/PWP2rxwhi?= =?us-ascii?Q?rWLpwEXWbkZlNzpXRMzCBK7NcI5rJAuJf68OB0U0J2BEFZU++2faK/w+pwvl?= =?us-ascii?Q?3ge0U3EIqck6WkZFqqJbf9ftKan4klWM2wCK7ihHsjmMlGsjrDGlKDe7oNTh?= =?us-ascii?Q?hDrMnIvDyYURLCAh2Z3g8OVbP+s8DNb0/B2HcpLX0GQvjXfYqxLIu6Qsd7S0?= =?us-ascii?Q?Ju1MEOWjbVLLs9oOYwFTTb6Ei0rMoxY2fCN2snFY4ciHCzzBeitX1+gEb49O?= =?us-ascii?Q?n/GeONKLsp98wiQ9T8X95QfWRh4KHRV2W0Ds6dScOOmjavipy3ijD+27EUUF?= =?us-ascii?Q?EmeaJjnv/uuS8rkya+SrRy7vgLF6o39p0410O9A3AHxad8OoxaUIh53jp2YO?= =?us-ascii?Q?61FZyzEhY/xifZXXHe6sOIRfnxQM2mDtpWEgpy/PQYY6y+a2NpdRf+JapAJx?= =?us-ascii?Q?x/mR0aRcYfAuqZgUxHzJgyn6HmN2p6h0Ty2BFKJpMVaufimT6d+nuXVJsw3A?= =?us-ascii?Q?f4j97dgXkkPNzLpTj7aaJoeduyHEcprshvfj+aSZ6WZpgn8N1rG4TJO3r3mZ?= =?us-ascii?Q?8h9kXV5C4QaUUlbWs/mBClyp0YjdQOeL155NUPwXWhzDjrbD/oquLdImuCqI?= =?us-ascii?Q?+dDCXIV201PmtB2DS/Y1cGTQmi8vekuThj42Wq/bzNx5NiwpUd2EMc/vupY1?= =?us-ascii?Q?ZHogref7ZPrmBIE423rLamRt9aPbvhWFcc8D1PEhr7ai50I9?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 447d277d-90d4-4f4d-5c2f-08df40d20389 X-MS-Exchange-CrossTenant-AuthSource: PH0PR12MB7957.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 12 Nov 2026 15:31:27.6710 (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: MbmEUr1GWelBuxWh0HYsInBrzUFD24mq4NbGAL2Vhn/iELWBDk2NrQS0lnhvf9XzoE/WoTZGWzcZB9TrmraByA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW4PR12MB6923 On Tue, Nov 10, 2026 at 09:26:17AM -0800, Stephen Hemminger wrote: > If a route does not fit in an empty dump skb, fib6_dump_node() > suspends the walker and inet6_dump_fib() returns 1. rtnl_dumpit() > then returns skb->len, which is 0, and the dump ends with NLMSG_DONE > and status 0, silently dropping the route and those after it. > > This became reachable when multipath routes started being dumped as a > single message with an RTA_MULTIPATH attribute; a wide enough route no > longer fits. > > Return -EMSGSIZE in this case, as IPv4 does. This depends on the > rtnl_dumpit() fix in the previous patch. > > Fixes: beb1afac518d ("net: ipv6: Add support to dump multipath routes via RTA_MULTIPATH attribute") > Signed-off-by: Stephen Hemminger Reviewed-by: Ido Schimmel FWIW, given that "It takes some non real world stuff to do this", I think these patches can be routed via net-next.