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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?+AyfgiwoAplq6sXq32n4wg/HOVxnd74oEKtF52G2chtE2eHgAj7IkCLBdcad?= =?us-ascii?Q?NokK1i9Dk/8LgMrSluxp5NM6gl9SVB6A3Rud66aoiBr/ARqa3+D+qYVNE4bm?= =?us-ascii?Q?oG+96qyA/EyH+55IDrwXpeoJwXxvcmuPiiCpeRBY2MSZA5SvIbP5ym6+DUNp?= =?us-ascii?Q?YlJlZHVESOLJUNgD1NKrBWoOqGuQHxmtPTPRZQqQBdh1ln1ynofvCiUdbmXu?= =?us-ascii?Q?grHC9Q39uidb3hWFVTDONI8krq2tenooWUpKiyL/oYXqi0zc5Q/hpm075/H2?= =?us-ascii?Q?IN+EUoLUXW4u11Yj9caLuDXdfsRzcstezUa/hlYtqptzj3fz0UNo4N3vwy+X?= =?us-ascii?Q?ekc9qI2CkOQxKRehon+wppA+oOf2Df1f5ALBm9PqXvEalgxwukwkiioOWxOw?= =?us-ascii?Q?3M8VsL27NBSkQTN6muGt3WIqcH8XtlGVGx685mvfzHtHYn2ah3bEt6rghfrB?= =?us-ascii?Q?AjzgRAfaFJAWTHgQfuZxWBVj+RJnkE5kKpYbz0NT2zjIULYS1VXuzmJ2OTV5?= =?us-ascii?Q?7wB4GVQ223VqUHh8rojxWIpddyPPJtkXN+dtIzGDLnyM9QjRGOq3JHVYgTbr?= =?us-ascii?Q?tlYS6E7KuAwRscx+qj+BSGwFCb9dsgc+oZw/rgdR1LLzEmIK8HVn+3lzIgdj?= =?us-ascii?Q?65fWzWnFriAoegK4Yoe9o3GLulprTSINcdY/7wjL2WZcqAJIKjy5IV7YKlGj?= =?us-ascii?Q?rBCugkUV2VkizWFGFSQMzP1KpBNMPphXsCb+P85DT8bc+Ya/6RaTZbAkOlY0?= =?us-ascii?Q?1OsTHNedNHMgLaZVRjtRsra9NepZTehSGWtzW9P4swjtst9z3KjFq+Z4MYL7?= =?us-ascii?Q?vWm4IPMjIBs2YdQFAk3IEK0mdcEwSi6uyNOjMcH56tXX0eYGOUdzn6kYoAqQ?= =?us-ascii?Q?66i4ElicZ3y5/codGr6xBbPMaWUA/p42KFKmzuJxWiESofZr42cKglncDqLo?= =?us-ascii?Q?Rxm8WuXueSsQOBvZ9U7p6STNGI0yvfSneS+89t28qd7B31ipuL8wquAxzKvZ?= =?us-ascii?Q?C5cuCyDc5I2XlQXOO489K3gTLx9k7WtT11BuURzRJkH31nalVTPSaZwwkxQ9?= =?us-ascii?Q?UVDd4eCuRr+kR2nKu4dh9Co0+fNRIqYp0vbZvqNM0TH1Pg2xJRVyM6QUMv6h?= =?us-ascii?Q?7GJTZTHfgy0K/rv5OoJ2XFd7qK8sxzhmxVj6cceWl5oY/vLxwTZZTho6UNtC?= =?us-ascii?Q?EXvBlAN91KjZdEPfmtsVLs7OEVXp6YKKiuiiiYisZogl8ZJ1kqFcV76m9Mc3?= =?us-ascii?Q?l/w6uN8zwkv5t67qICo6J7JciX50jTuWpIuyzmaKJ8hViXaRXg+ua6WLEgh/?= =?us-ascii?Q?4YjOH/0nCuvYvyF+pyq+xhqoj9dipnNtwfkHMBHS4N7mSMfr4fnnq39MtrAW?= =?us-ascii?Q?eGZW9paJyXMSPKPYBSESBpwLTGVlQRmuym8JD8G49HgXIeSHTgnLuIComamY?= =?us-ascii?Q?1ZOOE/tLvLR4vx2+iHXqhsUuBBisz9hWTka3gUaaNI3Ev+bAGYQdsKVmemVp?= =?us-ascii?Q?mn7JfJrORgLz0rFORW7PCwnXkhH+O9KO+1it6DWsCDgnk8x2P0GJ1nblp9G2?= =?us-ascii?Q?F4YSiq7a1/2yyKvWf4CBnLfN+LCvlzLJqsa7jFpOxcG0AaxhcHI1pwRwLxXk?= =?us-ascii?Q?eHCrtO78h5srbgCwwNgSDWSha5P9aedtwRPtJCa+biOq2vucgttrjJgXLi7O?= =?us-ascii?Q?AFPfupbeQ0JukAj8vFLmu0qpv9Uqke8eR/vP9rhgWVdYX1xPfrv2K8fH5lzn?= =?us-ascii?Q?lV3gUE+n8A=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 1f7e6cf4-79d0-4417-b6dd-08de77aace63 X-MS-Exchange-CrossTenant-AuthSource: SA3SPRMB0009.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 01 Mar 2026 15:54:22.6810 (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: aGsp6hME0Rx5HzxMDu3AmL7c2b9jRTWbSg1Z2SYnP364BHuAzRYNX/Nc7lyXiwUGbRMxDIKJRdfpe+siRsBDrA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV8PR12MB9665 On Fri, Feb 27, 2026 at 12:27:01PM +0100, Fernando Fernandez Mancera wrote: > When booting with the 'ipv6.disable=1' parameter, the nd_tbl is never > initialized because inet6_init() exits before ndisc_init() is called > which initializes it. If an IPv6 packet is injected into the interface, > route_shortcircuit() is called and a NULL pointer dereference happens on > neigh_lookup(). [...] > > Fix this by adding an early check on route_shortcircuit() when protocol > is IPv6. If ipv6_stub->nd_tbl is NULL, return false. > > Fixes: e15a00aafa4b ("vxlan: add ipv6 route short circuit support") > Signed-off-by: Fernando Fernandez Mancera > --- > drivers/net/vxlan/vxlan_core.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/net/vxlan/vxlan_core.c b/drivers/net/vxlan/vxlan_core.c > index 05558b6afecd..cbb9d1a2d8f9 100644 > --- a/drivers/net/vxlan/vxlan_core.c > +++ b/drivers/net/vxlan/vxlan_core.c > @@ -2130,6 +2130,8 @@ static bool route_shortcircuit(struct net_device *dev, struct sk_buff *skb) > { > struct ipv6hdr *pip6; > > + if (!ipv6_stub->nd_tbl) I was wondering why neigh_reduce() doesn't need a similar fix, but then I realized that's probably because of the __in6_dev_get() check earlier in the function. Maybe do the same here for consistency and mention that it relies on commit 804b09be09f8 ("vxlan: Add RCU read-side critical sections in the Tx path")? If you still prefer the current approach, then I would use ipv6_mod_enabled() instead of the NULL check. > + return false; > if (!pskb_may_pull(skb, sizeof(struct ipv6hdr))) > return false; > pip6 = ipv6_hdr(skb); > -- > 2.53.0 >