audit: type=1800 audit(1599034307.087:15): pid=8460 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op=collect_data cause=failed(directio) comm="syz-executor.1" name="bus" dev="sda1" ino=15817 res=0 ================================================================== BUG: KASAN: use-after-free in ex_handler_refcount+0x18f/0x1c0 arch/x86/mm/extable.c:49 Write of size 4 at addr ffff888050a743d8 by task syz-executor.5/6487 CPU: 1 PID: 6487 Comm: syz-executor.5 Not tainted 4.19.142-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2fe lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1c7 mm/kasan/report.c:354 kasan_report mm/kasan/report.c:412 [inline] __asan_report_store4_noabort+0x88/0x90 mm/kasan/report.c:437 ex_handler_refcount+0x18f/0x1c0 arch/x86/mm/extable.c:49 fixup_exception+0x8a/0xc3 arch/x86/mm/extable.c:197 do_trap_no_signal arch/x86/kernel/traps.c:209 [inline] do_trap+0x61/0x250 arch/x86/kernel/traps.c:258 do_error_trap+0x15d/0x310 arch/x86/kernel/traps.c:303 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:1038 RIP: 0010:csum_partial_copy_generic+0x608e/0x7820 Code: 49 8d 8c 24 80 00 00 00 0f 0b 48 8d 8d 80 00 00 00 0f 0b 48 8d 8d 80 00 00 00 0f 0b 49 8d 8c 24 b8 02 00 00 0f 0b 48 8d 4d 18 <0f> 0b 48 8d 8d b8 02 00 00 0f 0b 48 8d 4b 18 0f 0b 48 8d 8d 80 00 RSP: 0018:ffff888052dcf978 EFLAGS: 00010297 RAX: ffff888052dc6440 RBX: ffff888050ba2540 RCX: ffff888050a743d8 RDX: 0000000000000000 RSI: ffffffff86818d50 RDI: ffff888050a743c0 RBP: ffff888050a743c0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 R13: ffff888050ba2540 R14: ffffffff85b41074 R15: ffff888050a74828 l2cap_sock_destruct+0x47/0xf0 net/bluetooth/l2cap_sock.c:1488 __sk_destruct+0x4b/0x810 net/core/sock.c:1559 sk_destruct net/core/sock.c:1599 [inline] __sk_free+0x165/0x3b0 net/core/sock.c:1610 sock_wfree+0x12b/0x160 net/core/sock.c:1825 skb_release_head_state+0x158/0x2c0 net/core/skbuff.c:616 skb_release_all net/core/skbuff.c:629 [inline] __kfree_skb net/core/skbuff.c:645 [inline] kfree_skb+0xe1/0x3d0 net/core/skbuff.c:663 skb_queue_purge+0x14/0x30 net/core/skbuff.c:2858 hci_chan_del+0x129/0x180 net/bluetooth/hci_conn.c:1680 l2cap_conn_del+0x44f/0x6b0 net/bluetooth/l2cap_core.c:1736 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7435 [inline] l2cap_disconn_cfm+0x85/0xa0 net/bluetooth/l2cap_core.c:7428 hci_disconn_cfm include/net/bluetooth/hci_core.h:1261 [inline] hci_conn_hash_flush+0x114/0x220 net/bluetooth/hci_conn.c:1495 hci_dev_do_close+0x624/0xe70 net/bluetooth/hci_core.c:1666 hci_unregister_dev+0x17c/0x7f0 net/bluetooth/hci_core.c:3271 vhci_release+0x70/0xe0 drivers/bluetooth/hci_vhci.c:354 __fput+0x2ce/0x890 fs/file_table.c:278 task_work_run+0x148/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0xbb2/0x2b70 kernel/exit.c:887 do_group_exit+0x125/0x310 kernel/exit.c:990 __do_sys_exit_group kernel/exit.c:1001 [inline] __se_sys_exit_group kernel/exit.c:999 [inline] __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:999 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45d5b9 Code: 5d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 2b b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 IPVS: ftp: loaded support on port[0] = 21 RSP: 002b:00007ffcb1a491e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000016 RCX: 000000000045d5b9 RDX: 0000000000416e41 RSI: 00000000016a85f0 RDI: 0000000000000000 RBP: 00000000004c20cf R08: 000000000000000c R09: 0000000000000000 R10: 0000000002b8b940 R11: 0000000000000246 R12: 00007ffcb1a4a490 R13: 0000000002b94aa0 R14: 0000000000000000 R15: 00007ffcb1a4b520 Allocated by task 8388: kmem_cache_alloc_trace+0x12f/0x380 mm/slab.c:3625 kmalloc include/linux/slab.h:515 [inline] kzalloc include/linux/slab.h:709 [inline] l2cap_chan_create+0x40/0x380 net/bluetooth/l2cap_core.c:441 l2cap_sock_alloc.constprop.0+0x16c/0x210 net/bluetooth/l2cap_sock.c:1605 l2cap_sock_create+0x110/0x1b0 net/bluetooth/l2cap_sock.c:1636 bt_sock_create+0x154/0x2a0 net/bluetooth/af_bluetooth.c:130 __sock_create+0x3d8/0x740 net/socket.c:1276 sock_create net/socket.c:1316 [inline] __sys_socket+0xef/0x200 net/socket.c:1346 __do_sys_socket net/socket.c:1355 [inline] __se_sys_socket net/socket.c:1353 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1353 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 6487: __cache_free mm/slab.c:3503 [inline] kfree+0xcc/0x210 mm/slab.c:3822 l2cap_chan_destroy net/bluetooth/l2cap_core.c:479 [inline] kref_put include/linux/kref.h:70 [inline] l2cap_chan_put+0x16b/0x1c0 net/bluetooth/l2cap_core.c:493 l2cap_conn_del+0x3e3/0x6b0 net/bluetooth/l2cap_core.c:1731 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7435 [inline] l2cap_disconn_cfm+0x85/0xa0 net/bluetooth/l2cap_core.c:7428 hci_disconn_cfm include/net/bluetooth/hci_core.h:1261 [inline] hci_conn_hash_flush+0x114/0x220 net/bluetooth/hci_conn.c:1495 hci_dev_do_close+0x624/0xe70 net/bluetooth/hci_core.c:1666 hci_unregister_dev+0x17c/0x7f0 net/bluetooth/hci_core.c:3271 vhci_release+0x70/0xe0 drivers/bluetooth/hci_vhci.c:354 __fput+0x2ce/0x890 fs/file_table.c:278 task_work_run+0x148/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0xbb2/0x2b70 kernel/exit.c:887 do_group_exit+0x125/0x310 kernel/exit.c:990 __do_sys_exit_group kernel/exit.c:1001 [inline] __se_sys_exit_group kernel/exit.c:999 [inline] __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:999 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff888050a743c0 which belongs to the cache kmalloc-2048 of size 2048 The buggy address is located 24 bytes inside of 2048-byte region [ffff888050a743c0, ffff888050a74bc0) The buggy address belongs to the page: page:ffffea0001429d00 count:1 mapcount:0 mapping:ffff88812c39cc40 index:0x0 compound_mapcount: 0 flags: 0xfffe0000008100(slab|head) raw: 00fffe0000008100 ffffea0001429808 ffffea000142a308 ffff88812c39cc40 raw: 0000000000000000 ffff888050a743c0 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888050a74280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888050a74300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888050a74380: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ^ ffff888050a74400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888050a74480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== audit: type=1800 audit(1599034307.847:16): pid=8468 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op=collect_data cause=failed(directio) comm="syz-executor.1" name="bus" dev="sda1" ino=15817 res=0