================================================================== BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:728 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock+0x1887/0x1b10 kernel/locking/mutex.c:820 Read of size 8 at addr ffff88803a7ceae8 by task kworker/1:2/1042 CPU: 1 UID: 0 PID: 1042 Comm: kworker/1:2 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+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1d0 mm/kasan/report.c:595 __mutex_lock_common kernel/locking/mutex.c:728 [inline] __mutex_lock+0x1887/0x1b10 kernel/locking/mutex.c:820 l2cap_chan_timeout+0x6d/0x330 net/bluetooth/l2cap_core.c:417 process_one_work+0xa0e/0x1980 kernel/workqueue.c:3302 process_scheduled_works kernel/workqueue.c:3385 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3466 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 13379: 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:7001 l2cap_conn_add include/net/bluetooth/l2cap.h:840 [inline] l2cap_chan_connect+0x1435/0x1f90 net/bluetooth/l2cap_core.c:7192 l2cap_sock_connect+0x37a/0x770 net/bluetooth/l2cap_sock.c:256 kernel_connect+0x107/0x160 net/socket.c:3740 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:2148 __sys_connect+0x141/0x170 net/socket.c:2167 __do_sys_connect net/socket.c:2173 [inline] __se_sys_connect net/socket.c:2170 [inline] __x64_sys_connect+0x72/0xb0 net/socket.c:2170 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 13473: 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:2689 [inline] slab_free mm/slub.c:6250 [inline] kfree+0x223/0x6c0 mm/slub.c:6565 l2cap_conn_free net/bluetooth/l2cap_core.c:1823 [inline] kref_put include/linux/kref.h:65 [inline] l2cap_conn_put net/bluetooth/l2cap_core.c:1835 [inline] l2cap_conn_del+0x57f/0x710 net/bluetooth/l2cap_core.c:1815 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7440 [inline] l2cap_disconn_cfm+0x9f/0x100 net/bluetooth/l2cap_core.c:7433 hci_disconn_cfm include/net/bluetooth/hci_core.h:2154 [inline] hci_conn_hash_flush+0x10e/0x280 net/bluetooth/hci_conn.c:2734 hci_dev_close_sync+0x5a7/0x1240 net/bluetooth/hci_sync.c:5368 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/0xb50 fs/file_table.c:510 task_work_run+0x150/0x240 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x8d2/0x2a60 kernel/exit.c:975 do_group_exit+0xd5/0x2a0 kernel/exit.c:1117 get_signal+0x1ec7/0x21e0 kernel/signal.c:3037 arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x8b/0x4f0 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x706/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88803a7ce800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 744 bytes inside of freed 1024-byte region [ffff88803a7ce800, ffff88803a7cec00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x3a7c8 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 fffffffffffffe01 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5737, tgid 5737 (syz-executor), ts 64618986864, free_ts 64602617271 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x153/0x170 mm/page_alloc.c:1858 prep_new_page mm/page_alloc.c:1866 [inline] get_page_from_freelist+0x11a6/0x33b0 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x27c/0x2bc0 mm/page_alloc.c:5226 alloc_slab_page mm/slub.c:3278 [inline] allocate_slab mm/slub.c:3467 [inline] new_slab+0xa6/0x6c0 mm/slub.c:3525 refill_objects+0x277/0x420 mm/slub.c:7255 refill_sheaf mm/slub.c:2816 [inline] __pcs_replace_empty_main+0x375/0x650 mm/slub.c:4651 alloc_from_pcs mm/slub.c:4749 [inline] slab_alloc_node mm/slub.c:4883 [inline] __do_kmalloc_node mm/slub.c:5294 [inline] __kmalloc_node_noprof+0x69a/0x850 mm/slub.c:5301 kmalloc_node_noprof include/linux/slab.h:1081 [inline] qdisc_alloc+0xbb/0xb30 net/sched/sch_generic.c:976 qdisc_create_dflt+0x97/0x4b0 net/sched/sch_generic.c:1031 attach_one_default_qdisc net/sched/sch_generic.c:1197 [inline] netdev_for_each_tx_queue include/linux/netdevice.h:2706 [inline] attach_default_qdiscs net/sched/sch_generic.c:1215 [inline] dev_activate+0x64f/0xce0 net/sched/sch_generic.c:1274 __dev_open+0x490/0x8f0 net/core/dev.c:1711 __dev_change_flags+0x596/0x850 net/core/dev.c:9755 netif_change_flags+0x8d/0x160 net/core/dev.c:9818 do_setlink.isra.0+0x1ac4/0x3e60 net/core/rtnetlink.c:3181 rtnl_changelink net/core/rtnetlink.c:3800 [inline] __rtnl_newlink net/core/rtnetlink.c:3973 [inline] rtnl_newlink+0x11c2/0x2380 net/core/rtnetlink.c:4110 rtnetlink_rcv_msg+0x95e/0xe90 net/core/rtnetlink.c:6996 page last free pid 5851 tgid 5851 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1402 [inline] __free_frozen_pages+0x747/0x1040 mm/page_alloc.c:2943 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x47/0xf0 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:4569 [inline] slab_alloc_node mm/slub.c:4898 [inline] kmem_cache_alloc_noprof+0x241/0x6e0 mm/slub.c:4905 mt_alloc_one lib/maple_tree.c:139 [inline] mas_alloc_nodes lib/maple_tree.c:1089 [inline] mas_preallocate+0x1105/0x14a0 lib/maple_tree.c:4961 vma_iter_prealloc mm/vma.h:577 [inline] __mmap_new_vma mm/vma.c:2556 [inline] __mmap_region+0x124a/0x2da0 mm/vma.c:2771 mmap_region+0x35d/0x620 mm/vma.c:2857 do_mmap+0xc63/0x12f0 mm/mmap.c:560 vm_mmap_pgoff+0x29e/0x470 mm/util.c:581 vm_mmap+0x8e/0xc0 mm/util.c:617 elf_map fs/binfmt_elf.c:400 [inline] elf_load+0x2b1/0x720 fs/binfmt_elf.c:423 load_elf_binary+0x14b9/0x51b0 fs/binfmt_elf.c:1188 search_binary_handler fs/exec.c:1664 [inline] exec_binprm fs/exec.c:1696 [inline] bprm_execve fs/exec.c:1748 [inline] bprm_execve+0x8f5/0x1740 fs/exec.c:1724 kernel_execve+0x31e/0x3a0 fs/exec.c:1892 call_usermodehelper_exec_async+0x239/0x4b0 kernel/umh.c:109 Memory state around the buggy address: ffff88803a7ce980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88803a7cea00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88803a7cea80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88803a7ceb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88803a7ceb80: fb fb fb fb fb fb fb fb 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