================================================================== BUG: KASAN: use-after-free in __mutex_waiter_is_first kernel/locking/mutex.c:191 [inline] BUG: KASAN: use-after-free in __mutex_lock_common+0xc85/0x2390 kernel/locking/mutex.c:671 Read of size 8 at addr ffff88802aae9160 by task init/10919 CPU: 0 PID: 10919 Comm: init Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 print_address_description+0x60/0x2d0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xdf/0x130 mm/kasan/report.c:451 __mutex_waiter_is_first kernel/locking/mutex.c:191 [inline] __mutex_lock_common+0xc85/0x2390 kernel/locking/mutex.c:671 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743 device_lock include/linux/device.h:764 [inline] device_shutdown+0x1e2/0x5e0 drivers/base/core.c:4548 kernel_shutdown_prepare kernel/reboot.c:266 [inline] kernel_power_off+0x4f/0xb0 kernel/reboot.c:291 __do_sys_reboot kernel/reboot.c:366 [inline] __se_sys_reboot+0x391/0x3b0 kernel/reboot.c:312 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fd3b3c2d8d3 Code: ff 45 31 c9 6a 13 45 31 c0 31 c9 e8 67 8b f8 ff 48 83 c4 18 c3 66 90 89 fa be 69 19 12 28 bf ad de e1 fe b8 a9 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 05 c3 0f 1f 40 00 48 8b 15 f1 24 0d 00 f7 d8 RSP: 002b:00007ffdfcdf23e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a9 RAX: ffffffffffffffda RBX: 000000000000000c RCX: 00007fd3b3c2d8d3 RDX: 000000004321fedc RSI: 0000000028121969 RDI: 00000000fee1dead RBP: 000000004321fedc R08: 0000000000000000 R09: 0000000000000000 R10: 00007ffdfcdf23c0 R11: 0000000000000246 R12: 00007fd3b3dd0490 R13: 00007ffdfcdf243c R14: 00007fd3b3e08000 R15: 0000555660267d98 Allocated by task 5804: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc+0xb5/0xf0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:607 [inline] kzalloc include/linux/slab.h:738 [inline] nsim_bus_dev_new drivers/net/netdevsim/bus.c:408 [inline] new_device_store+0x194/0x740 drivers/net/netdevsim/bus.c:302 kernfs_fop_write_iter+0x379/0x4c0 fs/kernfs/file.c:296 call_write_iter include/linux/fs.h:2173 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0x712/0xd00 fs/read_write.c:594 ksys_write+0x14d/0x250 fs/read_write.c:647 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Freed by task 10604: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1710 [inline] slab_free_freelist_hook+0xea/0x170 mm/slub.c:1736 slab_free mm/slub.c:3504 [inline] kfree+0xef/0x2a0 mm/slub.c:4564 nsim_bus_dev_del drivers/net/netdevsim/bus.c:457 [inline] del_device_store+0x2d0/0x380 drivers/net/netdevsim/bus.c:354 kernfs_fop_write_iter+0x379/0x4c0 fs/kernfs/file.c:296 call_write_iter include/linux/fs.h:2173 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0x712/0xd00 fs/read_write.c:594 ksys_write+0x14d/0x250 fs/read_write.c:647 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Last potentially related work creation: kasan_save_stack+0x35/0x60 mm/kasan/common.c:38 kasan_record_aux_stack+0xb8/0x100 mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:3011 [inline] call_rcu+0x182/0x930 kernel/rcu/tree.c:3091 qdisc_put net/sched/sch_generic.c:1047 [inline] shutdown_scheduler_queue net/sched/sch_generic.c:1100 [inline] netdev_for_each_tx_queue include/linux/netdevice.h:2388 [inline] dev_shutdown+0x19f/0x710 net/sched/sch_generic.c:1408 unregister_netdevice_many+0xa0c/0x18f0 net/core/dev.c:11127 unregister_netdevice_queue+0x31c/0x360 net/core/dev.c:11067 unregister_netdevice include/linux/netdevice.h:3029 [inline] __tun_detach+0xd4a/0x1500 drivers/net/tun.c:686 tun_detach drivers/net/tun.c:702 [inline] tun_chr_close+0x109/0x1b0 drivers/net/tun.c:3440 __fput+0x234/0x930 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff88802aae9000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 352 bytes inside of 2048-byte region [ffff88802aae9000, ffff88802aae9800) The buggy address belongs to the page: page:ffffea0000aaba00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88802aae8000 pfn:0x2aae8 head:ffffea0000aaba00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea00019b0608 ffffea0001ca5a08 ffff888016842000 raw: ffff88802aae8000 0000000000080006 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4262, ts 77284536543, free_ts 76588622273 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1b77/0x1c60 mm/page_alloc.c:4192 __alloc_pages+0x1e1/0x470 mm/page_alloc.c:5487 alloc_slab_page mm/slub.c:1780 [inline] allocate_slab mm/slub.c:1917 [inline] new_slab+0xc0/0x4b0 mm/slub.c:1980 ___slab_alloc+0x81e/0xdf0 mm/slub.c:3013 __slab_alloc mm/slub.c:3100 [inline] slab_alloc_node mm/slub.c:3191 [inline] __kmalloc_node_track_caller+0x1fc/0x3a0 mm/slub.c:4963 kmalloc_reserve net/core/skbuff.c:356 [inline] __alloc_skb+0x22c/0x750 net/core/skbuff.c:427 alloc_skb include/linux/skbuff.h:1162 [inline] mld_newpack+0x12a/0xb90 net/ipv6/mcast.c:1745 add_grhead+0x5a/0x240 net/ipv6/mcast.c:1856 add_grec+0x1341/0x15d0 net/ipv6/mcast.c:1994 mld_send_initial_cr+0xed/0x240 net/ipv6/mcast.c:2241 ipv6_mc_dad_complete+0x84/0x210 net/ipv6/mcast.c:2252 addrconf_dad_completed+0x6c7/0xca0 net/ipv6/addrconf.c:4255 addrconf_dad_work+0xc70/0x1520 net/ipv6/addrconf.c:-1 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317 free_unref_page+0x94/0x280 mm/page_alloc.c:3396 qlist_free_all+0x35/0x90 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x150/0x160 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xd0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3225 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc_trace+0x103/0x2a0 mm/slub.c:3250 kmalloc include/linux/slab.h:607 [inline] netdevice_queue_work drivers/infiniband/core/roce_gid_mgmt.c:643 [inline] netdevice_event+0x324/0x900 drivers/infiniband/core/roce_gid_mgmt.c:802 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391 call_netdevice_notifiers_extack net/core/dev.c:2061 [inline] call_netdevice_notifiers net/core/dev.c:2075 [inline] __dev_notify_flags+0x178/0x2d0 net/core/dev.c:-1 dev_change_flags+0xe3/0x1a0 net/core/dev.c:8929 do_setlink+0xc01/0x3980 net/core/rtnetlink.c:2781 __rtnl_newlink net/core/rtnetlink.c:3452 [inline] rtnl_newlink+0x1419/0x17d0 net/core/rtnetlink.c:3574 rtnetlink_rcv_msg+0x7ff/0xe90 net/core/rtnetlink.c:5684 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2507 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344 Memory state around the buggy address: ffff88802aae9000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802aae9080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802aae9100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802aae9180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802aae9200: fb fb fb fb fb fb fb 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