================================================================== BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:101 [inline] BUG: KASAN: use-after-free in atomic64_try_cmpxchg_acquire include/asm-generic/atomic-instrumented.h:1515 [inline] BUG: KASAN: use-after-free in atomic_long_try_cmpxchg_acquire include/asm-generic/atomic-long.h:443 [inline] BUG: KASAN: use-after-free in __mutex_trylock_fast kernel/locking/mutex.c:173 [inline] BUG: KASAN: use-after-free in mutex_lock+0x7f/0xe0 kernel/locking/mutex.c:298 Write of size 8 at addr ffff8881073d8840 by task syz.9.4856/18305 CPU: 0 PID: 18305 Comm: syz.9.4856 Tainted: G W syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2025 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:77 dump_stack_lvl+0x169/0x1d8 lib/dump_stack.c:118 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:435 [inline] kasan_report+0xe2/0x130 mm/kasan/report.c:452 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x280/0x290 mm/kasan/generic.c:189 __kasan_check_write+0x14/0x20 mm/kasan/shadow.c:37 instrument_atomic_read_write include/linux/instrumented.h:101 [inline] atomic64_try_cmpxchg_acquire include/asm-generic/atomic-instrumented.h:1515 [inline] atomic_long_try_cmpxchg_acquire include/asm-generic/atomic-long.h:443 [inline] __mutex_trylock_fast kernel/locking/mutex.c:173 [inline] mutex_lock+0x7f/0xe0 kernel/locking/mutex.c:298 steam_input_open+0x91/0x160 drivers/hid/hid-steam.c:297 input_open_device+0x14c/0x2a0 drivers/input/input.c:635 evdev_open_device drivers/input/evdev.c:400 [inline] evdev_open+0x4d2/0x5e0 drivers/input/evdev.c:487 chrdev_open+0x597/0x670 fs/char_dev.c:414 do_dentry_open+0x793/0x1090 fs/open.c:819 vfs_open+0x73/0x80 fs/open.c:942 do_open fs/namei.c:3391 [inline] path_openat+0x27ad/0x3160 fs/namei.c:3509 do_filp_open+0x1b3/0x3e0 fs/namei.c:3536 do_sys_openat2+0x14c/0x6d0 fs/open.c:1217 do_sys_open fs/open.c:1233 [inline] __do_sys_openat fs/open.c:1249 [inline] __se_sys_openat fs/open.c:1244 [inline] __x64_sys_openat+0x136/0x160 fs/open.c:1244 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f2fdee1f590 Code: 48 89 44 24 20 75 93 44 89 54 24 0c e8 49 94 02 00 44 8b 54 24 0c 89 da 48 89 ee 41 89 c0 bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 38 44 89 c7 89 44 24 0c e8 9c 94 02 00 8b 44 RSP: 002b:00007f2fdd888b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000040001 RCX: 00007f2fdee1f590 RDX: 0000000000040001 RSI: 00007f2fdd888c10 RDI: 00000000ffffff9c RBP: 00007f2fdd888c10 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd R13: 00007f2fdf068038 R14: 00007f2fdf067fa0 R15: 00007fffa4c6f4b8 Allocated by task 7360: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:430 [inline] ____kasan_kmalloc mm/kasan/common.c:509 [inline] __kasan_kmalloc+0xda/0x110 mm/kasan/common.c:518 kasan_kmalloc include/linux/kasan.h:254 [inline] __kmalloc+0x1a7/0x330 mm/slub.c:4038 kmalloc include/linux/slab.h:557 [inline] kzalloc include/linux/slab.h:664 [inline] new_dir fs/proc/proc_sysctl.c:958 [inline] get_subdir fs/proc/proc_sysctl.c:1003 [inline] __register_sysctl_table+0xa38/0x1250 fs/proc/proc_sysctl.c:1352 register_net_sysctl+0x2c/0x40 net/sysctl_net.c:121 neigh_sysctl_register+0x998/0xa70 net/core/neighbour.c:3718 addrconf_sysctl_register+0xb3/0x1a0 net/ipv6/addrconf.c:7105 ipv6_add_dev+0xbaf/0x10a0 net/ipv6/addrconf.c:450 addrconf_notify+0x582/0xe90 net/ipv6/addrconf.c:3571 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0x90/0x100 kernel/notifier.c:410 call_netdevice_notifiers_info net/core/dev.c:2054 [inline] call_netdevice_notifiers_extack net/core/dev.c:2066 [inline] call_netdevice_notifiers+0x111/0x190 net/core/dev.c:2080 register_netdevice+0x1043/0x13c0 net/core/dev.c:10087 register_netdev+0x3e/0x50 net/core/dev.c:10180 vti6_init_net+0x2c0/0x380 net/ipv6/ip6_vti.c:1160 ops_init+0x1ba/0x4a0 net/core/net_namespace.c:144 setup_net+0x36d/0xb50 net/core/net_namespace.c:345 copy_net_ns+0x314/0x520 net/core/net_namespace.c:486 create_new_namespaces+0x3a2/0x650 kernel/nsproxy.c:110 copy_namespaces+0x1d1/0x220 kernel/nsproxy.c:179 copy_process+0x11b8/0x32c0 kernel/fork.c:2271 kernel_clone+0x23f/0x940 kernel/fork.c:2650 __do_sys_clone kernel/fork.c:2776 [inline] __se_sys_clone kernel/fork.c:2760 [inline] __x64_sys_clone+0x176/0x1d0 kernel/fork.c:2760 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb Freed by task 2621: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4a/0x70 mm/kasan/common.c:45 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370 ____kasan_slab_free+0x125/0x160 mm/kasan/common.c:362 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:370 kasan_slab_free include/linux/kasan.h:220 [inline] slab_free_hook mm/slub.c:1600 [inline] slab_free_freelist_hook+0xc5/0x190 mm/slub.c:1626 slab_free mm/slub.c:3208 [inline] kfree+0xc0/0x270 mm/slub.c:4196 skb_free_head net/core/skbuff.c:606 [inline] skb_release_data+0x532/0x670 net/core/skbuff.c:626 skb_release_all net/core/skbuff.c:680 [inline] __kfree_skb net/core/skbuff.c:694 [inline] kfree_skb+0xb9/0x2f0 net/core/skbuff.c:713 ip6_mc_input+0x235/0x2a0 net/ipv6/ip6_input.c:574 dst_input include/net/dst.h:461 [inline] ip6_rcv_finish+0x18c/0x360 net/ipv6/ip6_input.c:80 NF_HOOK include/linux/netfilter.h:299 [inline] ipv6_rcv+0xec/0x210 net/ipv6/ip6_input.c:301 __netif_receive_skb_one_core net/core/dev.c:5402 [inline] __netif_receive_skb+0xc8/0x280 net/core/dev.c:5516 process_backlog+0x368/0x600 net/core/dev.c:6423 napi_poll net/core/dev.c:6874 [inline] net_rx_action+0x432/0xdd0 net/core/dev.c:6944 __do_softirq+0x255/0x563 kernel/softirq.c:309 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:38 __kasan_record_aux_stack+0xd2/0x100 mm/kasan/generic.c:348 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358 kvfree_call_rcu+0x10c/0x620 kernel/rcu/tree.c:3539 drop_sysctl_table+0x2ef/0x410 fs/proc/proc_sysctl.c:1684 drop_sysctl_table+0x2de/0x410 fs/proc/proc_sysctl.c:1687 unregister_sysctl_table+0x75/0x120 fs/proc/proc_sysctl.c:1722 unregister_net_sysctl_table+0x15/0x20 net/sysctl_net.c:127 neigh_sysctl_unregister+0x78/0x90 net/core/neighbour.c:3737 addrconf_sysctl_unregister net/ipv6/addrconf.c:7121 [inline] addrconf_ifdown+0x1598/0x1800 net/ipv6/addrconf.c:3940 addrconf_notify+0x3bd/0xe90 net/ipv6/addrconf.c:-1 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0x90/0x100 kernel/notifier.c:410 call_netdevice_notifiers_info net/core/dev.c:2054 [inline] call_netdevice_notifiers_extack net/core/dev.c:2066 [inline] call_netdevice_notifiers net/core/dev.c:2080 [inline] unregister_netdevice_many+0xf8b/0x1980 net/core/dev.c:10767 vti6_exit_batch_net+0x26a/0x2b0 net/ipv6/ip6_vti.c:1186 ops_exit_list net/core/net_namespace.c:190 [inline] cleanup_net+0x5fb/0xb70 net/core/net_namespace.c:609 process_one_work+0x6e1/0xba0 kernel/workqueue.c:2301 worker_thread+0xa6a/0x13b0 kernel/workqueue.c:2447 kthread+0x346/0x3d0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Second to last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:38 __kasan_record_aux_stack+0xd2/0x100 mm/kasan/generic.c:348 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358 kvfree_call_rcu+0x10c/0x620 kernel/rcu/tree.c:3539 neigh_destroy+0x445/0x570 net/core/neighbour.c:865 neigh_release include/net/neighbour.h:427 [inline] neigh_cleanup_and_release+0x76/0x1a0 net/core/neighbour.c:104 neigh_flush_dev+0x642/0x820 net/core/neighbour.c:375 __neigh_ifdown+0x3f/0x380 net/core/neighbour.c:392 neigh_ifdown+0x1f/0x30 net/core/neighbour.c:409 rt6_disable_ip+0x616/0x6a0 net/ipv6/route.c:4802 addrconf_ifdown+0x144/0x1800 net/ipv6/addrconf.c:3788 addrconf_notify+0x3bd/0xe90 net/ipv6/addrconf.c:-1 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0x90/0x100 kernel/notifier.c:410 call_netdevice_notifiers_info net/core/dev.c:2054 [inline] call_netdevice_notifiers_extack net/core/dev.c:2066 [inline] call_netdevice_notifiers net/core/dev.c:2080 [inline] dev_close_many+0x330/0x4d0 net/core/dev.c:1655 unregister_netdevice_many+0x44c/0x1980 net/core/dev.c:10744 xfrmi_exit_batch_net+0x202/0x250 net/xfrm/xfrm_interface_core.c:772 ops_exit_list net/core/net_namespace.c:190 [inline] cleanup_net+0x5fb/0xb70 net/core/net_namespace.c:609 process_one_work+0x6e1/0xba0 kernel/workqueue.c:2301 worker_thread+0xa6a/0x13b0 kernel/workqueue.c:2447 kthread+0x346/0x3d0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 The buggy address belongs to the object at ffff8881073d8800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 64 bytes inside of 512-byte region [ffff8881073d8800, ffff8881073d8a00) The buggy address belongs to the page: page:ffffea00041cf600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1073d8 head:ffffea00041cf600 order:2 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head) raw: 4000000000010200 dead000000000100 dead000000000122 ffff888100043080 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 277, ts 28757665564, free_ts 28752804098 set_page_owner include/linux/page_owner.h:35 [inline] post_alloc_hook mm/page_alloc.c:2456 [inline] prep_new_page+0x179/0x180 mm/page_alloc.c:2462 get_page_from_freelist+0x2235/0x23d0 mm/page_alloc.c:4254 __alloc_pages_nodemask+0x268/0x5f0 mm/page_alloc.c:5370 alloc_slab_page mm/slub.c:-1 [inline] allocate_slab mm/slub.c:1813 [inline] new_slab+0x84/0x3f0 mm/slub.c:1874 new_slab_objects mm/slub.c:2632 [inline] ___slab_alloc+0x2a6/0x450 mm/slub.c:2796 __slab_alloc+0x63/0xa0 mm/slub.c:2836 slab_alloc_node mm/slub.c:2918 [inline] slab_alloc mm/slub.c:2960 [inline] __kmalloc_track_caller+0x1ef/0x320 mm/slub.c:4541 __kmalloc_reserve net/core/skbuff.c:144 [inline] __alloc_skb+0xdc/0x520 net/core/skbuff.c:212 alloc_skb include/linux/skbuff.h:1126 [inline] nlmsg_new include/net/netlink.h:953 [inline] inet_netconf_notify_devconf+0x169/0x220 net/ipv4/devinet.c:2120 __devinet_sysctl_register+0x324/0x390 net/ipv4/devinet.c:2604 devinet_sysctl_register+0x169/0x1e0 net/ipv4/devinet.c:2638 inetdev_init+0x273/0x480 net/ipv4/devinet.c:277 inetdev_event+0x1f8/0x1030 net/ipv4/devinet.c:1544 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0x90/0x100 kernel/notifier.c:410 call_netdevice_notifiers_info net/core/dev.c:2054 [inline] call_netdevice_notifiers_extack net/core/dev.c:2066 [inline] call_netdevice_notifiers+0x111/0x190 net/core/dev.c:2080 register_netdevice+0x1043/0x13c0 net/core/dev.c:10087 page last free stack trace: reset_page_owner include/linux/page_owner.h:28 [inline] free_pages_prepare mm/page_alloc.c:1349 [inline] __free_pages_ok+0x7fc/0x820 mm/page_alloc.c:1629 free_the_page mm/page_alloc.c:5431 [inline] __free_pages+0xdd/0x380 mm/page_alloc.c:5440 __free_slab+0xcf/0x190 mm/slub.c:1899 free_slab mm/slub.c:1914 [inline] discard_slab mm/slub.c:1920 [inline] unfreeze_partials+0x15f/0x190 mm/slub.c:2415 put_cpu_partial+0xc1/0x180 mm/slub.c:2451 __slab_free+0x2c9/0x3a0 mm/slub.c:3100 do_slab_free mm/slub.c:3196 [inline] ___cache_free+0x111/0x130 mm/slub.c:3215 qlink_free+0x50/0x90 mm/kasan/quarantine.c:157 qlist_free_all+0x5f/0xb0 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x14a/0x160 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xf0 mm/kasan/common.c:440 kasan_slab_alloc include/linux/kasan.h:244 [inline] slab_post_alloc_hook+0x5d/0x2f0 mm/slab.h:580 slab_alloc_node mm/slub.c:2952 [inline] slab_alloc mm/slub.c:2960 [inline] kmem_cache_alloc+0x165/0x2e0 mm/slub.c:2965 sock_alloc_inode+0x1b/0xb0 net/socket.c:253 alloc_inode fs/inode.c:233 [inline] new_inode_pseudo+0x62/0x210 fs/inode.c:968 sock_alloc net/socket.c:574 [inline] __sock_create+0x12c/0x770 net/socket.c:1400 Memory state around the buggy address: ffff8881073d8700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881073d8780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8881073d8800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881073d8880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881073d8900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== list_add corruption. prev is NULL. ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:24! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 18305 Comm: syz.9.4856 Tainted: G B W syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2025 RIP: 0010:__list_add_valid+0xad/0xf0 lib/list_debug.c:23 Code: 5d 41 5e 41 5f 5d c3 48 c7 c7 a0 25 20 85 4c 89 fe 4c 89 f2 48 89 d9 e8 a1 ff 31 02 0f 0b 48 c7 c7 a0 23 20 85 e8 93 ff 31 02 <0f> 0b 48 c7 c7 40 24 20 85 e8 85 ff 31 02 0f 0b 48 c7 c7 a0 24 20 RSP: 0018:ffffc90000e973e8 EFLAGS: 00010246 RAX: 0000000000000022 RBX: 1ffff920001d2e88 RCX: 53b868ab7c4b6100 RDX: ffffc90004918000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc90000e97410 R08: dffffc0000000000 R09: fffff520001d2db1 R10: fffff520001d2db1 R11: 1ffff920001d2db0 R12: 0000000000000000 R13: 1ffff11020e7b10b R14: ffffc90000e97560 R15: ffff8881073d8858 FS: 00007f2fdd8896c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2fdf069dac CR3: 000000011e2ef000 CR4: 00000000003526a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __list_add include/linux/list.h:67 [inline] list_add_tail include/linux/list.h:100 [inline] __mutex_add_waiter+0xc7/0x270 kernel/locking/mutex.c:218 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x3ce/0xc50 kernel/locking/mutex.c:1117 __mutex_lock_slowpath+0xe/0x10 kernel/locking/mutex.c:1379 mutex_lock+0xcf/0xe0 kernel/locking/mutex.c:299 steam_input_open+0x91/0x160 drivers/hid/hid-steam.c:297 input_open_device+0x14c/0x2a0 drivers/input/input.c:635 evdev_open_device drivers/input/evdev.c:400 [inline] evdev_open+0x4d2/0x5e0 drivers/input/evdev.c:487 chrdev_open+0x597/0x670 fs/char_dev.c:414 do_dentry_open+0x793/0x1090 fs/open.c:819 vfs_open+0x73/0x80 fs/open.c:942 do_open fs/namei.c:3391 [inline] path_openat+0x27ad/0x3160 fs/namei.c:3509 do_filp_open+0x1b3/0x3e0 fs/namei.c:3536 do_sys_openat2+0x14c/0x6d0 fs/open.c:1217 do_sys_open fs/open.c:1233 [inline] __do_sys_openat fs/open.c:1249 [inline] __se_sys_openat fs/open.c:1244 [inline] __x64_sys_openat+0x136/0x160 fs/open.c:1244 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f2fdee1f590 Code: 48 89 44 24 20 75 93 44 89 54 24 0c e8 49 94 02 00 44 8b 54 24 0c 89 da 48 89 ee 41 89 c0 bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 38 44 89 c7 89 44 24 0c e8 9c 94 02 00 8b 44 RSP: 002b:00007f2fdd888b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000040001 RCX: 00007f2fdee1f590 RDX: 0000000000040001 RSI: 00007f2fdd888c10 RDI: 00000000ffffff9c RBP: 00007f2fdd888c10 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd R13: 00007f2fdf068038 R14: 00007f2fdf067fa0 R15: 00007fffa4c6f4b8 Modules linked in: ---[ end trace e4556976fe71c1fb ]--- RIP: 0010:__list_add_valid+0xad/0xf0 lib/list_debug.c:23 Code: 5d 41 5e 41 5f 5d c3 48 c7 c7 a0 25 20 85 4c 89 fe 4c 89 f2 48 89 d9 e8 a1 ff 31 02 0f 0b 48 c7 c7 a0 23 20 85 e8 93 ff 31 02 <0f> 0b 48 c7 c7 40 24 20 85 e8 85 ff 31 02 0f 0b 48 c7 c7 a0 24 20 RSP: 0018:ffffc90000e973e8 EFLAGS: 00010246 RAX: 0000000000000022 RBX: 1ffff920001d2e88 RCX: 53b868ab7c4b6100 RDX: ffffc90004918000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc90000e97410 R08: dffffc0000000000 R09: fffff520001d2db1 R10: fffff520001d2db1 R11: 1ffff920001d2db0 R12: 0000000000000000 R13: 1ffff11020e7b10b R14: ffffc90000e97560 R15: ffff8881073d8858 FS: 00007f2fdd8896c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2fdf069dac CR3: 000000011e2ef000 CR4: 00000000003526a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400