==================================================================
BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:577 [inline]
BUG: KASAN: slab-use-after-free in __mutex_lock+0x147/0x1350 kernel/locking/mutex.c:760
Read of size 8 at addr ffff8880466968b0 by task kworker/u8:8/3024

CPU: 0 UID: 0 PID: 3024 Comm: kworker/u8:8 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: udp_tunnel_nic udp_tunnel_nic_device_sync_work
Call Trace:
 <TASK>
 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:577 [inline]
 __mutex_lock+0x147/0x1350 kernel/locking/mutex.c:760
 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+0xae1/0x17b0 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
 </TASK>

Allocated by task 12350:
 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:388 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:405
 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+0x1b3/0x3e0 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:11293
 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1034 [inline]
 nsim_create+0xae8/0xf10 drivers/net/netdevsim/netdev.c:1105
 __nsim_dev_port_add+0x6b6/0xb10 drivers/net/netdevsim/dev.c:1438
 nsim_dev_port_add_all+0x37/0xf0 drivers/net/netdevsim/dev.c:1494
 nsim_dev_reload_create drivers/net/netdevsim/dev.c:1546 [inline]
 nsim_dev_reload_up+0x451/0x780 drivers/net/netdevsim/dev.c:1003
 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+0x212/0x300 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+0x82f/0x9e0 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+0x21c/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 12349:
 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:243 [inline]
 __kasan_slab_free+0x5b/0x80 mm/kasan/common.c:275
 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+0x1b3/0x3e0 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:12215
 unregister_netdevice_many net/core/dev.c:12278 [inline]
 unregister_netdevice_queue+0x33c/0x380 net/core/dev.c:12122
 unregister_netdevice include/linux/netdevice.h:3385 [inline]
 nsim_destroy+0x1dd/0x670 drivers/net/netdevsim/netdev.c:1140
 __nsim_dev_port_del+0x14d/0x1b0 drivers/net/netdevsim/dev.c:1473
 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1485 [inline]
 nsim_dev_reload_destroy+0x288/0x490 drivers/net/netdevsim/dev.c:1707
 nsim_dev_reload_down+0x8a/0xc0 drivers/net/netdevsim/dev.c:983
 devlink_reload+0x1b3/0x8d0 net/devlink/dev.c:461
 devlink_nl_reload_doit+0xb35/0xd50 net/devlink/dev.c:584
 genl_family_rcv_msg_doit+0x212/0x300 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+0x82f/0x9e0 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+0x21c/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:112
 geneve_offload_rx_ports+0xd7/0x160 drivers/net/geneve.c:1188
 geneve_netdevice_event+0x6a/0x80 drivers/net/geneve.c:-1
 notifier_call_chain+0x1b3/0x3e0 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+0x1b3/0x3e0 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:11293
 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1034 [inline]
 nsim_create+0xae8/0xf10 drivers/net/netdevsim/netdev.c:1105
 __nsim_dev_port_add+0x6b6/0xb10 drivers/net/netdevsim/dev.c:1438
 nsim_dev_port_add_all+0x37/0xf0 drivers/net/netdevsim/dev.c:1494
 nsim_dev_reload_create drivers/net/netdevsim/dev.c:1546 [inline]
 nsim_dev_reload_up+0x451/0x780 drivers/net/netdevsim/dev.c:1003
 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+0x212/0x300 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+0x82f/0x9e0 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+0x21c/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:112
 vxlan_offload_rx_ports+0x139/0x200 drivers/net/vxlan/vxlan_core.c:3310
 vxlan_netdevice_event+0x111/0x470 drivers/net/vxlan/vxlan_core.c:-1
 notifier_call_chain+0x1b3/0x3e0 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+0x1b3/0x3e0 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:11293
 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1034 [inline]
 nsim_create+0xae8/0xf10 drivers/net/netdevsim/netdev.c:1105
 __nsim_dev_port_add+0x6b6/0xb10 drivers/net/netdevsim/dev.c:1438
 nsim_dev_port_add_all+0x37/0xf0 drivers/net/netdevsim/dev.c:1494
 nsim_dev_reload_create drivers/net/netdevsim/dev.c:1546 [inline]
 nsim_dev_reload_up+0x451/0x780 drivers/net/netdevsim/dev.c:1003
 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+0x212/0x300 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+0x82f/0x9e0 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+0x21c/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 ffff888046696800
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 176 bytes inside of
 freed 256-byte region [ffff888046696800, ffff888046696900)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x46696
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801a441b40 dead000000000100 dead000000000122
raw: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801a441b40 dead000000000100 dead000000000122
head: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000
head: 00fff00000000001 ffffea000119a581 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 10209, tgid 10185 (syz.2.1137), ts 307021100495, free_ts 306054497088
 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]
 __kmalloc_cache_noprof+0x296/0x3d0 mm/slub.c:4391
 kmalloc_noprof include/linux/slab.h:905 [inline]
 tc_action_net_init include/net/act_api.h:160 [inline]
 skbmod_init_net+0x65/0x190 net/sched/act_skbmod.c:296
 ops_init+0x359/0x5c0 net/core/net_namespace.c:136
 setup_net+0x10c/0x320 net/core/net_namespace.c:438
 copy_net_ns+0x31b/0x4d0 net/core/net_namespace.c:570
 create_new_namespaces+0x3f3/0x720 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:218
 ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3127
 __do_sys_unshare kernel/fork.c:3198 [inline]
 __se_sys_unshare kernel/fork.c:3196 [inline]
 __x64_sys_unshare+0x38/0x50 kernel/fork.c:3196
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
page last free pid 9633 tgid 9633 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895
 kasan_depopulate_vmalloc_pte+0x74/0xa0 mm/kasan/shadow.c:472
 apply_to_pte_range mm/memory.c:3015 [inline]
 apply_to_pmd_range mm/memory.c:3059 [inline]
 apply_to_pud_range mm/memory.c:3095 [inline]
 apply_to_p4d_range mm/memory.c:3131 [inline]
 __apply_to_page_range+0xb8f/0x1380 mm/memory.c:3167
 kasan_release_vmalloc+0xa2/0xd0 mm/kasan/shadow.c:593
 kasan_release_vmalloc_node mm/vmalloc.c:2249 [inline]
 purge_vmap_node+0x214/0x8f0 mm/vmalloc.c:2266
 __purge_vmap_area_lazy+0x7a4/0xb40 mm/vmalloc.c:2356
 drain_vmap_area_work+0x27/0x40 mm/vmalloc.c:2390
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0xae1/0x17b0 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

Memory state around the buggy address:
 ffff888046696780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888046696800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888046696880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff888046696900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888046696980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================