================================================================== 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 ffff8880561802e0 by task kworker/1:1/60 CPU: 1 UID: 0 PID: 60 Comm: kworker/1:1 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+0x9d7/0x1920 kernel/workqueue.c:3275 process_scheduled_works kernel/workqueue.c:3358 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3439 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 8741: 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:6950 l2cap_conn_add include/net/bluetooth/l2cap.h:839 [inline] l2cap_chan_connect+0x1435/0x1f90 net/bluetooth/l2cap_core.c:7141 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] __ia32_sys_connect+0x71/0xb0 net/socket.c:2111 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xe3/0x8c0 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e Freed by task 8754: 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:2692 [inline] slab_free mm/slub.c:6168 [inline] kfree+0x1f6/0x6b0 mm/slub.c:6486 l2cap_conn_free net/bluetooth/l2cap_core.c:1806 [inline] kref_put include/linux/kref.h:65 [inline] l2cap_conn_put net/bluetooth/l2cap_core.c:1818 [inline] l2cap_conn_del+0x5be/0x770 net/bluetooth/l2cap_core.c:1798 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7389 [inline] l2cap_disconn_cfm+0x9f/0x100 net/bluetooth/l2cap_core.c:7382 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_do_reset net/bluetooth/hci_core.c:567 [inline] hci_dev_reset+0x249/0x650 net/bluetooth/hci_core.c:611 hci_sock_ioctl+0x5c5/0x7e0 net/bluetooth/hci_sock.c:1140 hci_sock_compat_ioctl+0x43/0x80 net/bluetooth/hci_sock.c:1181 compat_sock_ioctl+0x179/0x760 net/socket.c:3526 __do_compat_sys_ioctl fs/ioctl.c:695 [inline] __se_compat_sys_ioctl fs/ioctl.c:638 [inline] __ia32_compat_sys_ioctl+0x2cf/0x360 fs/ioctl.c:638 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xe3/0x8c0 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e The buggy address belongs to the object at ffff888056180000 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 736 bytes inside of freed 1024-byte region [ffff888056180000, ffff888056180400) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x56180 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x4fff00000000040(head|node=1|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 04fff00000000040 ffff88801b842dc0 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000 head: 04fff00000000040 ffff88801b842dc0 dead000000000100 dead000000000122 head: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000 head: 04fff00000000003 ffffea0001586001 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 5937, tgid 5937 (syz-executor), ts 53852344151, free_ts 48162407872 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:3296 [inline] allocate_slab mm/slub.c:3485 [inline] new_slab+0xa6/0x6c0 mm/slub.c:3543 refill_objects+0x26b/0x400 mm/slub.c:7178 refill_sheaf mm/slub.c:2818 [inline] alloc_full_sheaf mm/slub.c:2839 [inline] __pcs_replace_empty_main+0x1ab/0x600 mm/slub.c:4629 alloc_from_pcs mm/slub.c:4720 [inline] slab_alloc_node mm/slub.c:4854 [inline] __kmalloc_cache_noprof+0x493/0x6f0 mm/slub.c:5378 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] batadv_hardif_add_interface net/batman-adv/hard-interface.c:874 [inline] batadv_hard_if_event+0x853/0x13e0 net/batman-adv/hard-interface.c:958 notifier_call_chain+0x99/0x420 kernel/notifier.c:85 call_netdevice_notifiers_info+0xbe/0x110 net/core/dev.c:2249 call_netdevice_notifiers_extack net/core/dev.c:2287 [inline] call_netdevice_notifiers net/core/dev.c:2301 [inline] register_netdevice+0x16e6/0x2210 net/core/dev.c:11462 macvlan_common_newlink+0xf70/0x18b0 drivers/net/macvlan.c:1546 macvtap_newlink drivers/net/macvtap.c:108 [inline] macvtap_newlink+0x17a/0x240 drivers/net/macvtap.c:80 rtnl_newlink_create net/core/rtnetlink.c:3840 [inline] __rtnl_newlink net/core/rtnetlink.c:3957 [inline] rtnl_newlink+0x1494/0x2380 net/core/rtnetlink.c:4072 rtnetlink_rcv_msg+0x95e/0xe90 net/core/rtnetlink.c:6958 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2550 page last free pid 5923 tgid 5923 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 vfree.part.0+0x12b/0x9d0 mm/vmalloc.c:3479 vfree+0x55/0x80 mm/vmalloc.c:3456 kcov_put kernel/kcov.c:442 [inline] kcov_put kernel/kcov.c:438 [inline] kcov_close+0x34/0x60 kernel/kcov.c:543 __fput+0x3ff/0xb40 fs/file_table.c:469 fput_close_sync+0x118/0x250 fs/file_table.c:574 __do_sys_close fs/open.c:1509 [inline] __se_sys_close fs/open.c:1494 [inline] __ia32_sys_close+0x8b/0x120 fs/open.c:1494 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xe3/0x8c0 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e Memory state around the buggy address: ffff888056180180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888056180200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888056180280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888056180300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888056180380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================