================================================================== BUG: KASAN: slab-use-after-free in __mutex_waiter_is_first kernel/locking/mutex.c:199 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:694 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock+0x1861/0x1b90 kernel/locking/mutex.c:776 Read of size 8 at addr ffff8880368bb2e0 by task kworker/0:3/5996 CPU: 0 UID: 0 PID: 5996 Comm: kworker/0:3 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Workqueue: events l2cap_chan_timeout Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x156/0x4c9 mm/kasan/report.c:482 kasan_report+0xdf/0x1e0 mm/kasan/report.c:595 __mutex_waiter_is_first kernel/locking/mutex.c:199 [inline] __mutex_lock_common kernel/locking/mutex.c:694 [inline] __mutex_lock+0x1861/0x1b90 kernel/locking/mutex.c:776 l2cap_chan_timeout+0x6d/0x330 net/bluetooth/l2cap_core.c:417 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276 process_scheduled_works kernel/workqueue.c:3359 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 11581: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] l2cap_conn_add.part.0+0x60/0xb00 net/bluetooth/l2cap_core.c:6961 l2cap_conn_add include/net/bluetooth/l2cap.h:839 [inline] l2cap_chan_connect+0x1435/0x1f90 net/bluetooth/l2cap_core.c:7152 l2cap_sock_connect+0x37a/0x770 net/bluetooth/l2cap_sock.c:256 kernel_connect+0x107/0x160 net/socket.c:3634 rfcomm_session_create net/bluetooth/rfcomm/core.c:811 [inline] __rfcomm_dlc_open net/bluetooth/rfcomm/core.c:388 [inline] rfcomm_dlc_open+0x838/0xac0 net/bluetooth/rfcomm/core.c:431 rfcomm_sock_connect+0x42c/0x690 net/bluetooth/rfcomm/sock.c:410 __sys_connect_file+0x141/0x1a0 net/socket.c:2089 __sys_connect+0x141/0x170 net/socket.c:2108 __do_sys_connect net/socket.c:2114 [inline] __se_sys_connect net/socket.c:2111 [inline] __x64_sys_connect+0x72/0xb0 net/socket.c:2111 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 7823: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2685 [inline] slab_free mm/slub.c:6165 [inline] kfree+0x1f6/0x6b0 mm/slub.c:6483 l2cap_conn_free net/bluetooth/l2cap_core.c:1802 [inline] kref_put include/linux/kref.h:65 [inline] l2cap_conn_put net/bluetooth/l2cap_core.c:1814 [inline] l2cap_conn_del+0x5be/0x770 net/bluetooth/l2cap_core.c:1794 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7400 [inline] l2cap_disconn_cfm+0x9f/0x100 net/bluetooth/l2cap_core.c:7393 hci_disconn_cfm include/net/bluetooth/hci_core.h:2154 [inline] hci_conn_hash_flush+0x10e/0x280 net/bluetooth/hci_conn.c:2644 hci_dev_close_sync+0x5a7/0x1240 net/bluetooth/hci_sync.c:5358 hci_dev_do_close+0x2e/0xb0 net/bluetooth/hci_core.c:502 hci_unregister_dev+0x227/0x670 net/bluetooth/hci_core.c:2716 vhci_release+0x17d/0x230 drivers/bluetooth/hci_vhci.c:690 __fput+0x3ff/0xb40 fs/file_table.c:469 task_work_run+0x150/0x240 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x8b8/0x2b60 kernel/exit.c:976 do_group_exit+0xd5/0x2a0 kernel/exit.c:1118 get_signal+0x1ec7/0x21e0 kernel/signal.c:3034 arch_do_signal_or_restart+0x91/0x7a0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x86/0x4a0 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x67c/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880368bb000 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 736 bytes inside of freed 1024-byte region [ffff8880368bb000, ffff8880368bb400) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x368b8 head: order:3 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 ffff88801b842dc0 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801b842dc0 dead000000000100 dead000000000122 head: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0000da2e01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5997, tgid 5997 (kworker/2:3), ts 85025307840, free_ts 85018707711 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x153/0x170 mm/page_alloc.c:1889 prep_new_page mm/page_alloc.c:1897 [inline] get_page_from_freelist+0x111d/0x3140 mm/page_alloc.c:3962 __alloc_frozen_pages_noprof+0x27c/0x2ba0 mm/page_alloc.c:5250 alloc_slab_page mm/slub.c:3292 [inline] allocate_slab mm/slub.c:3481 [inline] new_slab+0xa6/0x6b0 mm/slub.c:3539 refill_objects+0x26b/0x400 mm/slub.c:7175 refill_sheaf mm/slub.c:2812 [inline] __pcs_replace_empty_main+0x1ab/0x660 mm/slub.c:4615 alloc_from_pcs mm/slub.c:4717 [inline] slab_alloc_node mm/slub.c:4851 [inline] __do_kmalloc_node mm/slub.c:5259 [inline] __kmalloc_noprof+0x688/0x850 mm/slub.c:5272 kmalloc_noprof include/linux/slab.h:954 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] neigh_alloc net/core/neighbour.c:521 [inline] ___neigh_create+0x155d/0x2970 net/core/neighbour.c:655 ip6_finish_output2+0xffa/0x1ce0 net/ipv6/ip6_output.c:128 __ip6_finish_output+0x357/0xdf0 net/ipv6/ip6_output.c:208 ip6_finish_output net/ipv6/ip6_output.c:219 [inline] NF_HOOK_COND include/linux/netfilter.h:307 [inline] ip6_output+0x2aa/0xa60 net/ipv6/ip6_output.c:246 dst_output include/net/dst.h:470 [inline] NF_HOOK include/linux/netfilter.h:318 [inline] NF_HOOK.constprop.0+0x115/0x5a0 include/linux/netfilter.h:312 mld_sendpack+0x8f7/0xec0 net/ipv6/mcast.c:1855 mld_send_cr net/ipv6/mcast.c:2154 [inline] mld_ifc_work+0x75a/0xc10 net/ipv6/mcast.c:2693 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276 process_scheduled_works kernel/workqueue.c:3359 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440 page last free pid 1159 tgid 1159 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1433 [inline] __free_frozen_pages+0x7e1/0x10d0 mm/page_alloc.c:2978 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x47/0xe0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4538 [inline] slab_alloc_node mm/slub.c:4866 [inline] kmem_cache_alloc_node_noprof+0x25a/0x6f0 mm/slub.c:4918 __alloc_skb+0x140/0x710 net/core/skbuff.c:702 alloc_skb include/linux/skbuff.h:1383 [inline] nlmsg_new include/net/netlink.h:1055 [inline] rtmsg_ifinfo_build_skb+0x81/0x260 net/core/rtnetlink.c:4407 rtmsg_ifinfo_event net/core/rtnetlink.c:4449 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:4439 [inline] rtmsg_ifinfo+0xa4/0x1b0 net/core/rtnetlink.c:4458 netif_state_change+0x17f/0x380 net/core/dev.c:1605 linkwatch_do_dev net/core/link_watch.c:186 [inline] linkwatch_do_dev+0xdb/0x110 net/core/link_watch.c:166 __linkwatch_run_queue+0x3a9/0x900 net/core/link_watch.c:240 linkwatch_event+0x8f/0xc0 net/core/link_watch.c:314 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276 process_scheduled_works kernel/workqueue.c:3359 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 Memory state around the buggy address: ffff8880368bb180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880368bb200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880368bb280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880368bb300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880368bb380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================