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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?WM94sDHotQGofSPFJSbPHyC5obavGF6vlKTLdYdJTCekJSwfUkZKk+59hiI7?= =?us-ascii?Q?JTzyMvTDymd8hS6rQ3lyCGXFIOwbzsxdUBeNY9w4+t+POTEfaxA17k1kmGMT?= =?us-ascii?Q?vQjP0h604rR9YTkzQdlEMVBf8bog6MsDuDjBN562Y5LAFwiiAKKpb5zi5k7g?= =?us-ascii?Q?18X8Xxt24J74lHYf86j0OCpfbl3zcjcr/FRjz0bKwQyE6VpQQX8LrhW7XnSk?= =?us-ascii?Q?2s7Vsn7VdhaXyfsV6HUKnYTUcDk34WpnjiaUvoafpJBQlptkHjC9lg8m63fC?= =?us-ascii?Q?Vu8LhBx0BFRlFCpinnLxOF+fBKl5Gp9YsZc8il2XebzjZvwBLg/4H66nuQEX?= =?us-ascii?Q?alKcYwz5ruopC3JPZhooDyfMtW/qtl3VbX3R/sxbTbcmqQgGTXs02V0ScLGc?= =?us-ascii?Q?VTc+SasDFqJBXs3CzXOiMuzfMqegvKhHPgpbCF0LS2aZBIlotX+v+Y3Aoin0?= =?us-ascii?Q?mX8IiDQTkgF2h6b5zsugcFzDmVQPhlkdwdCVc23fiwS/XXckHRsWxJpzXRkS?= =?us-ascii?Q?l8p8a3fFiVzEiUsRnA55ARYUeJHVo3pF/VTRRxB5CVpCgOCKYYJtIrMVypk/?= =?us-ascii?Q?+xpo5aCGNpJ+3zV6HOF0Dsmhr6LUB/JI41hk/cb/bQBbNu+XI73G0UrVFiEt?= =?us-ascii?Q?a9Se2iO+PiDVPgh/VeePwrvGoxNIwNZIMl4gkRskhZmKGMMTl3+C0egAhHL4?= =?us-ascii?Q?ln1xIS7ca+KsFSdZrkJeeU/hmUM9Q45D6Xs//x5hiH3w5HF2gByH9XeAf5IJ?= =?us-ascii?Q?iwRY5aJ7Nr4qmuhaCRij/UFODhJibUGWdry1VuTWuFOhLUZs11hZtGuHza6R?= =?us-ascii?Q?D2PZtPp1X+3zOkKuqjE7LcBskuIBQCLkQNal5VyR7QgdVLqQRuKSqaYdBfad?= =?us-ascii?Q?V7DUmgJ3DQTJGVb+/ihJhgjmlv2qUygCKm6lAT4ROVMUz3QCFG8QrH1MN2Nb?= =?us-ascii?Q?r8RZy+4o4pYA1stpKPjvagXveG7w4xynEVHnj5bQPQKpt+aVcaDfMoDYuuJh?= =?us-ascii?Q?/bUhDAKq+2zuS5EXRYLGNS37uh7mJ5FGw9zNTMbv4JaPX323+cXxv3uw14Tt?= =?us-ascii?Q?biKY454+F2APJbws5cVslVeBDXg1x5IWf+f+adejZpgxKCtE/+W4jtWMBQLp?= =?us-ascii?Q?9BkZArg5t5XjkaOKxwAb1besmjg5XVWJGwX0h89A2wxhv7snK1h9Ep/boskq?= =?us-ascii?Q?IX3lpO02Cg5z/fBKCeGjv1jIdnzF8oyyVd4WBLQENhPdnXiI4w4/IT7tjqWc?= =?us-ascii?Q?9MEmzm1ArIB70RhbWs52HxD1qe0Gh/pHtdoZFWKYDA68/uyxg+AoOwsPoCp9?= =?us-ascii?Q?SKW7eDXG2rjKKonshh40T7Wl8y1FgBTPE7wZnPt28iYi4kTNY0SEk6VkVVLm?= =?us-ascii?Q?MKNqnDXeuKMbSIDk1p9SoRf+JldhGVUPFsn2Iiey2SgdSOejLpLohnVUYH9J?= =?us-ascii?Q?GyTJLYPKY5NpziX9cmXQZE8t1LMUkZJf7NwYoIadli1aGwlD2xZdcyo8UZQY?= =?us-ascii?Q?Ozy0DElXMoBS10zNnszlMsY0IlRvsj+Bu75dk6u+hA51EQADH2IUPtOZUT1L?= =?us-ascii?Q?TD9NQsA5NRNCJ77dhjPDdGX5Ffj2LFFEkREAnbVkZKsLGg9cjLvwQWGMFSc8?= =?us-ascii?Q?EnsFRww/DnnQFaPp2QwKO/4OwxNW1ptICHGG1qDH35twu4VyLcSjQq71Kqz1?= =?us-ascii?Q?NiXB35xxUyneeRaIR8/yx232oDu/mzrBa9dpULo/egsrsEqm?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 8f9ec4ec-c986-426b-1b6e-08df21edda25 X-MS-Exchange-CrossTenant-AuthSource: PH0PR12MB7957.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Oct 2026 08:02:36.2158 (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: 4JSCQPOWc1rXTwPKqSlCEkG7x9tUtyi6e4iy/YGfNezjgr2+rkL4nBksobHV2ZMpkTNWmKbxUZBftEoTrZGB3w== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ2PR12MB9115 On Fri, Oct 02, 2026 at 01:50:59PM +0900, Daehyeon Ko wrote: > Commit 4ce5dc9316de ("inet: switch inet_dump_fib() to RCU > protection") allowed IPv4 FIB dumps to run concurrently with nexthop > replacement. > > fib_dump_info_fnhe() uses fib_info_num_path() as the loop bound, > then fib_info_nhc() independently reloads nh->nh_grp. If > RTM_NEWNEXTHOP replaces a group with fewer paths between those loads, > fib_info_nhc() returns NULL and the dump dereferences it through > nhc_flags. > > Stop the walk when the indexed path is absent. Nexthop groups are > dense, so the current snapshot has no later path. > > Fixes: 4ce5dc9316de ("inet: switch inet_dump_fib() to RCU protection") > Reported-by: Ido Schimmel > Link: https://lore.kernel.org/netdev/20261001170513.GA1657889@shredder/ > Cc: stable@vger.kernel.org > Assisted-by: LLM > Signed-off-by: Daehyeon Ko <4ncienth@gmail.com> Reviewed-by: Ido Schimmel