BUG: spinlock bad magic on CPU#0, kworker/0:6/9773 ================================================================== BUG: KASAN: slab-out-of-bounds in task_pid_nr include/linux/sched.h:1440 [inline] BUG: KASAN: slab-out-of-bounds in spin_dump kernel/locking/spinlock_debug.c:65 [inline] BUG: KASAN: slab-out-of-bounds in spin_bug.cold+0x95/0x9e kernel/locking/spinlock_debug.c:75 Read of size 4 at addr ffff8880812387c8 by task kworker/0:6/9773 CPU: 0 PID: 9773 Comm: kworker/0:6 Not tainted 5.14.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events l2cap_chan_timeout Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105 print_address_description.constprop.0.cold+0x6c/0x309 mm/kasan/report.c:233 __kasan_report mm/kasan/report.c:419 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:436 task_pid_nr include/linux/sched.h:1440 [inline] spin_dump kernel/locking/spinlock_debug.c:65 [inline] spin_bug.cold+0x95/0x9e kernel/locking/spinlock_debug.c:75 debug_spin_lock_before kernel/locking/spinlock_debug.c:83 [inline] do_raw_spin_lock+0x216/0x2b0 kernel/locking/spinlock_debug.c:112 spin_lock_bh include/linux/spinlock.h:359 [inline] lock_sock_nested+0x40/0x120 net/core/sock.c:3162 l2cap_sock_teardown_cb+0xa1/0x660 net/bluetooth/l2cap_sock.c:1528 l2cap_chan_del+0xbc/0xa80 net/bluetooth/l2cap_core.c:622 l2cap_chan_close+0x1b9/0xaf0 net/bluetooth/l2cap_core.c:825 l2cap_chan_timeout+0x17e/0x2f0 net/bluetooth/l2cap_core.c:436 process_one_work+0x98d/0x1630 kernel/workqueue.c:2276 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 16745: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 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 mm/kasan/common.c:472 [inline] __kasan_kmalloc+0x9b/0xd0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:596 [inline] kzalloc include/linux/slab.h:721 [inline] __register_sysctl_table+0x112/0x1090 fs/proc/proc_sysctl.c:1318 __addrconf_sysctl_register+0x1db/0x3d0 net/ipv6/addrconf.c:6965 addrconf_sysctl_register net/ipv6/addrconf.c:7012 [inline] addrconf_sysctl_register+0x139/0x1d0 net/ipv6/addrconf.c:7001 ipv6_add_dev+0x936/0x1120 net/ipv6/addrconf.c:445 addrconf_notify+0x872/0x2400 net/ipv6/addrconf.c:3491 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:2122 call_netdevice_notifiers_extack net/core/dev.c:2134 [inline] call_netdevice_notifiers net/core/dev.c:2148 [inline] register_netdevice+0x106b/0x1500 net/core/dev.c:10362 veth_newlink+0x58c/0xad0 drivers/net/veth.c:1547 __rtnl_newlink+0x106e/0x1760 net/core/rtnetlink.c:3460 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3508 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5574 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929 sock_sendmsg_nosec net/socket.c:703 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:723 __sys_sendto+0x21c/0x320 net/socket.c:2019 __do_sys_sendto net/socket.c:2031 [inline] __se_sys_sendto net/socket.c:2027 [inline] __x64_sys_sendto+0xdd/0x1b0 net/socket.c:2027 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Last potentially related work creation: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_record_aux_stack+0xe5/0x110 mm/kasan/generic.c:348 kvfree_call_rcu+0x74/0x990 kernel/rcu/tree.c:3594 drop_sysctl_table+0x3c0/0x4e0 fs/proc/proc_sysctl.c:1647 unregister_sysctl_table fs/proc/proc_sysctl.c:1685 [inline] unregister_sysctl_table+0xc2/0x190 fs/proc/proc_sysctl.c:1660 __addrconf_sysctl_unregister net/ipv6/addrconf.c:6994 [inline] addrconf_sysctl_unregister+0xee/0x1c0 net/ipv6/addrconf.c:7022 addrconf_ifdown.isra.0+0xf8f/0x15b0 net/ipv6/addrconf.c:3849 addrconf_notify+0x606/0x2400 net/ipv6/addrconf.c:3631 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:2122 call_netdevice_notifiers_extack net/core/dev.c:2134 [inline] call_netdevice_notifiers net/core/dev.c:2148 [inline] unregister_netdevice_many+0x951/0x1790 net/core/dev.c:11075 unregister_netdevice_queue+0x2dd/0x3c0 net/core/dev.c:11009 unregister_netdevice include/linux/netdevice.h:2969 [inline] ppp_release+0x216/0x240 drivers/net/ppp/ppp_generic.c:404 __fput+0x288/0x920 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff888081238000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1992 bytes inside of 2048-byte region [ffff888081238000, ffff888081238800) The buggy address belongs to the page: page:ffffea0002048e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88808123d000 pfn:0x81238 head:ffffea0002048e00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0001f33408 ffffea0000891c08 ffff888010842000 raw: ffff88808123d000 0000000000080004 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 0xd2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 8486, ts 189855522898, free_ts 0 prep_new_page mm/page_alloc.c:2433 [inline] get_page_from_freelist+0xa72/0x2f80 mm/page_alloc.c:4166 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5388 alloc_pages+0x18c/0x2a0 mm/mempolicy.c:2244 alloc_slab_page mm/slub.c:1688 [inline] allocate_slab+0x32e/0x4b0 mm/slub.c:1828 new_slab mm/slub.c:1891 [inline] new_slab_objects mm/slub.c:2637 [inline] ___slab_alloc+0x4ba/0x820 mm/slub.c:2800 __slab_alloc.constprop.0+0xa7/0xf0 mm/slub.c:2840 slab_alloc_node mm/slub.c:2922 [inline] __kmalloc_node_track_caller+0x2e3/0x360 mm/slub.c:4648 kmalloc_reserve net/core/skbuff.c:355 [inline] pskb_expand_head+0x15e/0x1060 net/core/skbuff.c:1685 netlink_trim+0x1ea/0x240 net/netlink/af_netlink.c:1296 netlink_broadcast_filtered+0x65/0xdc0 net/netlink/af_netlink.c:1501 netlink_broadcast net/netlink/af_netlink.c:1546 [inline] nlmsg_multicast include/net/netlink.h:1033 [inline] nlmsg_notify+0x90/0x250 net/netlink/af_netlink.c:2547 rtnl_notify net/core/rtnetlink.c:741 [inline] rtmsg_ifinfo_send net/core/rtnetlink.c:3835 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:3850 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:3838 [inline] rtmsg_ifinfo+0xf0/0x120 net/core/rtnetlink.c:3856 __dev_notify_flags+0x226/0x2b0 net/core/dev.c:8844 dev_change_flags+0x112/0x170 net/core/dev.c:8886 do_setlink+0x90a/0x3900 net/core/rtnetlink.c:2721 __rtnl_newlink+0xddb/0x1760 net/core/rtnetlink.c:3393 page_owner free stack trace missing Memory state around the buggy address: ffff888081238680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc ffff888081238700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888081238780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888081238800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888081238880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc 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