================================================================== BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:581 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock+0x147/0x1360 kernel/locking/mutex.c:764 Read of size 8 at addr ffff8880319e66b0 by task kworker/u8:2/36 CPU: 0 UID: 0 PID: 36 Comm: kworker/u8:2 Not tainted 6.16.0-rc6-next-20250718-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: udp_tunnel_nic udp_tunnel_nic_device_sync_work Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 __mutex_lock_common kernel/locking/mutex.c:581 [inline] __mutex_lock+0x147/0x1360 kernel/locking/mutex.c:764 udp_tunnel_nic_device_sync_work+0x39/0xa50 net/ipv4/udp_tunnel_nic.c:737 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 13255: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4365 [inline] __kmalloc_noprof+0x27a/0x4f0 mm/slub.c:4377 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] udp_tunnel_nic_alloc net/ipv4/udp_tunnel_nic.c:756 [inline] udp_tunnel_nic_register net/ipv4/udp_tunnel_nic.c:833 [inline] udp_tunnel_nic_netdevice_event+0x854/0x19f0 net/ipv4/udp_tunnel_nic.c:931 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers net/core/dev.c:2281 [inline] register_netdevice+0x1608/0x1ae0 net/core/dev.c:11209 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1010 [inline] nsim_create+0xae8/0xf10 drivers/net/netdevsim/netdev.c:1081 __nsim_dev_port_add+0x6b6/0xb10 drivers/net/netdevsim/dev.c:1436 nsim_dev_port_add_all+0x37/0xf0 drivers/net/netdevsim/dev.c:1492 nsim_dev_reload_create drivers/net/netdevsim/dev.c:1544 [inline] nsim_dev_reload_up+0x451/0x780 drivers/net/netdevsim/dev.c:1001 devlink_reload+0x4e9/0x8d0 net/devlink/dev.c:474 devlink_nl_reload_doit+0xb35/0xd50 net/devlink/dev.c:584 genl_family_rcv_msg_doit+0x215/0x300 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x60e/0x790 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x205/0x470 net/netlink/af_netlink.c:2552 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:729 ____sys_sendmsg+0x505/0x830 net/socket.c:2614 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668 __sys_sendmsg net/socket.c:2700 [inline] __do_sys_sendmsg net/socket.c:2705 [inline] __se_sys_sendmsg net/socket.c:2703 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 13255: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2417 [inline] slab_free mm/slub.c:4680 [inline] kfree+0x18e/0x440 mm/slub.c:4879 udp_tunnel_nic_free net/ipv4/udp_tunnel_nic.c:785 [inline] udp_tunnel_nic_unregister net/ipv4/udp_tunnel_nic.c:910 [inline] udp_tunnel_nic_netdevice_event+0x1332/0x19f0 net/ipv4/udp_tunnel_nic.c:942 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers net/core/dev.c:2281 [inline] unregister_netdevice_many_notify+0x14d7/0x1ff0 net/core/dev.c:12130 unregister_netdevice_many net/core/dev.c:12193 [inline] unregister_netdevice_queue+0x33c/0x380 net/core/dev.c:12037 unregister_netdevice include/linux/netdevice.h:3381 [inline] nsim_destroy+0x217/0x6a0 drivers/net/netdevsim/netdev.c:1116 __nsim_dev_port_del+0x14d/0x1b0 drivers/net/netdevsim/dev.c:1471 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1483 [inline] nsim_dev_port_add_all+0xae/0xf0 drivers/net/netdevsim/dev.c:1499 nsim_dev_reload_create drivers/net/netdevsim/dev.c:1544 [inline] nsim_dev_reload_up+0x451/0x780 drivers/net/netdevsim/dev.c:1001 devlink_reload+0x4e9/0x8d0 net/devlink/dev.c:474 devlink_nl_reload_doit+0xb35/0xd50 net/devlink/dev.c:584 genl_family_rcv_msg_doit+0x215/0x300 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x60e/0x790 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x205/0x470 net/netlink/af_netlink.c:2552 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:729 ____sys_sendmsg+0x505/0x830 net/socket.c:2614 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668 __sys_sendmsg net/socket.c:2700 [inline] __do_sys_sendmsg net/socket.c:2705 [inline] __se_sys_sendmsg net/socket.c:2703 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:548 insert_work+0x3d/0x330 kernel/workqueue.c:2184 __queue_work+0xbaf/0xfb0 kernel/workqueue.c:2343 queue_work_on+0x181/0x270 kernel/workqueue.c:2390 queue_work include/linux/workqueue.h:669 [inline] udp_tunnel_nic_device_sync net/ipv4/udp_tunnel_nic.c:307 [inline] __udp_tunnel_nic_add_port+0xb71/0xd60 net/ipv4/udp_tunnel_nic.c:523 udp_tunnel_nic_add_port include/net/udp_tunnel.h:371 [inline] udp_tunnel_push_rx_port+0x180/0x200 net/ipv4/udp_tunnel_core.c:111 geneve_offload_rx_ports+0xd7/0x160 drivers/net/geneve.c:1188 geneve_netdevice_event+0x6a/0x80 drivers/net/geneve.c:-1 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers+0x88/0xc0 net/core/dev.c:2281 udp_tunnel_get_rx_info include/net/udp_tunnel.h:438 [inline] udp_tunnel_nic_register net/ipv4/udp_tunnel_nic.c:855 [inline] udp_tunnel_nic_netdevice_event+0x134d/0x19f0 net/ipv4/udp_tunnel_nic.c:931 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers net/core/dev.c:2281 [inline] register_netdevice+0x1608/0x1ae0 net/core/dev.c:11209 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1010 [inline] nsim_create+0xae8/0xf10 drivers/net/netdevsim/netdev.c:1081 __nsim_dev_port_add+0x6b6/0xb10 drivers/net/netdevsim/dev.c:1436 nsim_dev_port_add_all+0x37/0xf0 drivers/net/netdevsim/dev.c:1492 nsim_dev_reload_create drivers/net/netdevsim/dev.c:1544 [inline] nsim_dev_reload_up+0x451/0x780 drivers/net/netdevsim/dev.c:1001 devlink_reload+0x4e9/0x8d0 net/devlink/dev.c:474 devlink_nl_reload_doit+0xb35/0xd50 net/devlink/dev.c:584 genl_family_rcv_msg_doit+0x215/0x300 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x60e/0x790 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x205/0x470 net/netlink/af_netlink.c:2552 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:729 ____sys_sendmsg+0x505/0x830 net/socket.c:2614 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668 __sys_sendmsg net/socket.c:2700 [inline] __do_sys_sendmsg net/socket.c:2705 [inline] __se_sys_sendmsg net/socket.c:2703 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Second to last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:548 insert_work+0x3d/0x330 kernel/workqueue.c:2184 __queue_work+0xcd2/0xfb0 kernel/workqueue.c:2339 queue_work_on+0x181/0x270 kernel/workqueue.c:2390 queue_work include/linux/workqueue.h:669 [inline] udp_tunnel_nic_device_sync net/ipv4/udp_tunnel_nic.c:307 [inline] __udp_tunnel_nic_add_port+0xb71/0xd60 net/ipv4/udp_tunnel_nic.c:523 udp_tunnel_nic_add_port include/net/udp_tunnel.h:371 [inline] udp_tunnel_push_rx_port+0x180/0x200 net/ipv4/udp_tunnel_core.c:111 geneve_offload_rx_ports+0xd7/0x160 drivers/net/geneve.c:1188 geneve_netdevice_event+0x6a/0x80 drivers/net/geneve.c:-1 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers+0x88/0xc0 net/core/dev.c:2281 udp_tunnel_get_rx_info include/net/udp_tunnel.h:438 [inline] udp_tunnel_nic_register net/ipv4/udp_tunnel_nic.c:855 [inline] udp_tunnel_nic_netdevice_event+0x134d/0x19f0 net/ipv4/udp_tunnel_nic.c:931 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers net/core/dev.c:2281 [inline] register_netdevice+0x1608/0x1ae0 net/core/dev.c:11209 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1010 [inline] nsim_create+0xae8/0xf10 drivers/net/netdevsim/netdev.c:1081 __nsim_dev_port_add+0x6b6/0xb10 drivers/net/netdevsim/dev.c:1436 nsim_dev_port_add_all+0x37/0xf0 drivers/net/netdevsim/dev.c:1492 nsim_dev_reload_create drivers/net/netdevsim/dev.c:1544 [inline] nsim_dev_reload_up+0x451/0x780 drivers/net/netdevsim/dev.c:1001 devlink_reload+0x4e9/0x8d0 net/devlink/dev.c:474 devlink_nl_reload_doit+0xb35/0xd50 net/devlink/dev.c:584 genl_family_rcv_msg_doit+0x215/0x300 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x60e/0x790 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x205/0x470 net/netlink/af_netlink.c:2552 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:729 ____sys_sendmsg+0x505/0x830 net/socket.c:2614 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668 __sys_sendmsg net/socket.c:2700 [inline] __do_sys_sendmsg net/socket.c:2705 [inline] __se_sys_sendmsg net/socket.c:2703 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880319e6600 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 176 bytes inside of freed 256-byte region [ffff8880319e6600, ffff8880319e6700) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x319e6 head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 ksm flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801a441b40 ffffea00009a0b00 dead000000000003 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801a441b40 ffffea00009a0b00 dead000000000003 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000001 ffffea0000c67981 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 19688962302, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:2487 [inline] allocate_slab+0x8a/0x370 mm/slub.c:2655 new_slab mm/slub.c:2709 [inline] ___slab_alloc+0xbeb/0x1410 mm/slub.c:3891 __slab_alloc mm/slub.c:3981 [inline] __slab_alloc_node mm/slub.c:4056 [inline] slab_alloc_node mm/slub.c:4217 [inline] __do_kmalloc_node mm/slub.c:4364 [inline] __kmalloc_node_track_caller_noprof+0x2f8/0x4e0 mm/slub.c:4384 __do_krealloc mm/slub.c:4942 [inline] krealloc_noprof+0x124/0x340 mm/slub.c:4995 add_sysfs_param+0xc9/0xa20 kernel/params.c:654 kernel_add_sysfs_param+0xb4/0x130 kernel/params.c:811 param_sysfs_builtin+0x1de/0x290 kernel/params.c:850 param_sysfs_builtin_init+0x32/0x40 kernel/params.c:986 do_one_initcall+0x233/0x820 init/main.c:1269 do_initcall_level+0x137/0x1f0 init/main.c:1331 do_initcalls+0x69/0xd0 init/main.c:1347 kernel_init_freeable+0x3d9/0x590 init/main.c:1579 page_owner free stack trace missing Memory state around the buggy address: ffff8880319e6580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880319e6600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880319e6680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880319e6700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880319e6780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================