input: syz0 as /devices/virtual/input/input56 ================================================================== 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 ffff88811e78bc40 by task syz.5.4971/18523 CPU: 0 PID: 18523 Comm: syz.5.4971 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: 0033:0x7f36d7def510 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:00007f36d6858b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f36d7def510 RDX: 0000000000000000 RSI: 00007f36d6858c10 RDI: 00000000ffffff9c RBP: 00007f36d6858c10 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd R13: 00007f36d8038038 R14: 00007f36d8037fa0 R15: 00007ffd4fb974d8 Allocated by task 14883: 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] kmem_cache_alloc_trace+0x184/0x2e0 mm/slub.c:2979 kmalloc include/linux/slab.h:552 [inline] kzalloc include/linux/slab.h:664 [inline] inetdev_init+0x84/0x480 net/ipv4/devinet.c:259 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 __ip_tunnel_create+0x2bf/0x380 net/ipv4/ip_tunnel.c:267 ip_tunnel_init_net+0x290/0x740 net/ipv4/ip_tunnel.c:1083 ipip_init_net+0x29/0x30 net/ipv4/ipip.c:645 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 347: 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] consume_skb+0xab/0x1f0 net/core/skbuff.c:851 netlink_broadcast_filtered+0x117d/0x1270 net/netlink/af_netlink.c:1530 netlink_broadcast net/netlink/af_netlink.c:1552 [inline] nlmsg_multicast include/net/netlink.h:1033 [inline] nlmsg_notify+0xed/0x1b0 net/netlink/af_netlink.c:2546 rtnl_notify+0x9a/0xc0 net/core/rtnetlink.c:737 inet_netconf_notify_devconf+0x1c2/0x220 net/ipv4/devinet.c:2132 __devinet_sysctl_unregister net/ipv4/devinet.c:2625 [inline] devinet_sysctl_unregister net/ipv4/devinet.c:2649 [inline] inetdev_destroy net/ipv4/devinet.c:326 [inline] inetdev_event+0x7c6/0x1030 net/ipv4/devinet.c:1612 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 default_device_exit_batch+0x330/0x390 net/core/dev.c:11287 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 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 __call_rcu kernel/rcu/tree.c:2980 [inline] call_rcu+0x10e/0x1050 kernel/rcu/tree.c:3054 inetdev_destroy net/ipv4/devinet.c:330 [inline] inetdev_event+0x83c/0x1030 net/ipv4/devinet.c:1612 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 ip_tunnel_delete_nets+0x343/0x390 net/ipv4/ip_tunnel.c:1136 ipip_exit_batch_net+0x22/0x30 net/ipv4/ipip.c:650 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 put_css_set_locked+0x9b7/0x9f0 kernel/cgroup/cgroup.c:980 cgroup_migrate_finish+0x3a8/0x420 kernel/cgroup/cgroup.c:2681 cgroup_attach_task+0x383/0x560 kernel/cgroup/cgroup.c:2873 cgroup_attach_task_all+0xb4/0x140 kernel/cgroup/cgroup-v1.c:73 kvm_vm_worker_thread+0xcb/0x280 virt/kvm/kvm_main.c:5109 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 ffff88811e78bc00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 64 bytes inside of 512-byte region [ffff88811e78bc00, ffff88811e78be00) The buggy address belongs to the page: page:ffffea000479e200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11e788 head:ffffea000479e200 order:2 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head) raw: 4000000000010200 ffffea00042db400 0000000300000003 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 5546, ts 220379104541, free_ts 220375244120 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] netlink_alloc_large_skb net/netlink/af_netlink.c:1178 [inline] netlink_sendmsg+0x5f6/0xb30 net/netlink/af_netlink.c:1889 sock_sendmsg_nosec net/socket.c:652 [inline] __sock_sendmsg net/socket.c:664 [inline] __sys_sendto+0x41d/0x580 net/socket.c:2006 __do_sys_sendto net/socket.c:2018 [inline] __se_sys_sendto net/socket.c:2014 [inline] __x64_sys_sendto+0xe5/0x100 net/socket.c:2014 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb 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] __kmalloc+0x183/0x330 mm/slub.c:4034 kmalloc include/linux/slab.h:557 [inline] kzalloc include/linux/slab.h:664 [inline] fib6_info_alloc+0x34/0xe0 net/ipv6/ip6_fib.c:154 ip6_route_info_create+0x4d2/0x1490 net/ipv6/route.c:3673 ip6_route_add+0x27/0x130 net/ipv6/route.c:3769 Memory state around the buggy address: ffff88811e78bb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88811e78bb80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88811e78bc00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88811e78bc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88811e78bd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== general protection fault, probably for non-canonical address 0xdffffc0000000213: 0000 [#1] PREEMPT SMP KASAN KASAN: probably user-memory-access in range [0x0000000000001098-0x000000000000109f] CPU: 1 PID: 18523 Comm: syz.5.4971 Tainted: G B W syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2025 RIP: 0010:steam_send_report+0x66/0x310 drivers/hid/hid-steam.c:172 Code: 80 3c 18 00 74 12 4c 89 f7 e8 f6 34 3f fe 48 ba 00 00 00 00 00 fc ff df 4d 8b 26 49 8d 9c 24 98 10 00 00 48 89 d8 48 c1 e8 03 <80> 3c 10 00 74 12 48 89 df e8 cc 34 3f fe 48 ba 00 00 00 00 00 fc RSP: 0018:ffffc90000cc7668 EFLAGS: 00010202 RAX: 0000000000000213 RBX: 0000000000001098 RCX: 0000000000000282 RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffff88811e78bc30 RBP: ffffc90000cc76b0 R08: dffffc0000000000 R09: fffff52000198ec9 R10: fffff52000198ec9 R11: 1ffff92000198ec8 R12: 0000000000000000 R13: 1ffff92000198ed8 R14: ffff88811e78bc30 R15: ffffc90000cc76e0 FS: 00007f36d68596c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff5c5dd9ad8 CR3: 0000000121a8a000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: steam_send_report_byte drivers/hid/hid-steam.c:212 [inline] steam_set_lizard_mode drivers/hid/hid-steam.c:285 [inline] steam_input_open+0xde/0x160 drivers/hid/hid-steam.c:299 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: 0033:0x7f36d7def510 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:00007f36d6858b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f36d7def510 RDX: 0000000000000000 RSI: 00007f36d6858c10 RDI: 00000000ffffff9c RBP: 00007f36d6858c10 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd R13: 00007f36d8038038 R14: 00007f36d8037fa0 R15: 00007ffd4fb974d8 Modules linked in: ---[ end trace f48319baf1e26424 ]--- RIP: 0010:steam_send_report+0x66/0x310 drivers/hid/hid-steam.c:172 Code: 80 3c 18 00 74 12 4c 89 f7 e8 f6 34 3f fe 48 ba 00 00 00 00 00 fc ff df 4d 8b 26 49 8d 9c 24 98 10 00 00 48 89 d8 48 c1 e8 03 <80> 3c 10 00 74 12 48 89 df e8 cc 34 3f fe 48 ba 00 00 00 00 00 fc RSP: 0018:ffffc90000cc7668 EFLAGS: 00010202 RAX: 0000000000000213 RBX: 0000000000001098 RCX: 0000000000000282 RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffff88811e78bc30 RBP: ffffc90000cc76b0 R08: dffffc0000000000 R09: fffff52000198ec9 R10: fffff52000198ec9 R11: 1ffff92000198ec8 R12: 0000000000000000 R13: 1ffff92000198ed8 R14: ffff88811e78bc30 R15: ffffc90000cc76e0 FS: 00007f36d68596c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f36d7e4e470 CR3: 0000000121a8a000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 80 3c 18 00 cmpb $0x0,(%rax,%rbx,1) 4: 74 12 je 0x18 6: 4c 89 f7 mov %r14,%rdi 9: e8 f6 34 3f fe call 0xfe3f3504 e: 48 ba 00 00 00 00 00 movabs $0xdffffc0000000000,%rdx 15: fc ff df 18: 4d 8b 26 mov (%r14),%r12 1b: 49 8d 9c 24 98 10 00 lea 0x1098(%r12),%rbx 22: 00 23: 48 89 d8 mov %rbx,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 80 3c 10 00 cmpb $0x0,(%rax,%rdx,1) <-- trapping instruction 2e: 74 12 je 0x42 30: 48 89 df mov %rbx,%rdi 33: e8 cc 34 3f fe call 0xfe3f3504 38: 48 rex.W 39: ba 00 00 00 00 mov $0x0,%edx 3e: 00 fc add %bh,%ah