================================================================== BUG: KASAN: use-after-free in hci_chan_del+0x1b4/0x1f0 net/bluetooth/hci_conn.c:1683 Read of size 8 at addr ffff88809d630d98 by task syz-executor.5/14566 CPU: 0 PID: 14566 Comm: syz-executor.5 Not tainted 4.19.178-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/0x2ef lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354 kasan_report mm/kasan/report.c:412 [inline] __asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433 hci_chan_del+0x1b4/0x1f0 net/bluetooth/hci_conn.c:1683 l2cap_conn_del+0x45e/0x6e0 net/bluetooth/l2cap_core.c:1739 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7441 [inline] l2cap_disconn_cfm+0x98/0xd0 net/bluetooth/l2cap_core.c:7434 hci_disconn_cfm include/net/bluetooth/hci_core.h:1261 [inline] hci_conn_hash_flush+0x127/0x260 net/bluetooth/hci_conn.c:1512 hci_dev_do_close+0x659/0xf10 net/bluetooth/hci_core.c:1668 hci_unregister_dev+0x18b/0x910 net/bluetooth/hci_core.c:3273 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+0xbf3/0x2be0 kernel/exit.c:870 do_group_exit+0x125/0x310 kernel/exit.c:967 get_signal+0x3f2/0x1f70 kernel/signal.c:2589 do_signal+0x8f/0x1670 arch/x86/kernel/signal.c:821 exit_to_usermode_loop+0x204/0x2a0 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465f69 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f7f6c929218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000056bf68 RCX: 0000000000465f69 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000056bf68 RBP: 000000000056bf60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf6c R13: 00007ffe320fd62f R14: 00007f7f6c929300 R15: 0000000000022000 Allocated by task 8120: kmem_cache_alloc_trace+0x12f/0x380 mm/slab.c:3625 kmalloc include/linux/slab.h:515 [inline] sock_alloc_inode+0x5f/0x250 net/socket.c:247 alloc_inode+0x5d/0x180 fs/inode.c:211 new_inode_pseudo+0x14/0xe0 fs/inode.c:911 sock_alloc+0x3c/0x260 net/socket.c:547 __sock_create+0xba/0x740 net/socket.c:1240 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 9: __cache_free mm/slab.c:3503 [inline] kfree+0xcc/0x210 mm/slab.c:3822 __rcu_reclaim kernel/rcu/rcu.h:231 [inline] rcu_do_batch kernel/rcu/tree.c:2584 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2897 [inline] __rcu_process_callbacks kernel/rcu/tree.c:2864 [inline] rcu_process_callbacks+0xa0d/0x18b0 kernel/rcu/tree.c:2881 __do_softirq+0x265/0x980 kernel/softirq.c:292 The buggy address belongs to the object at ffff88809d630d80 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 24 bytes inside of 128-byte region [ffff88809d630d80, ffff88809d630e00) The buggy address belongs to the page: page:ffffea0002758c00 count:1 mapcount:0 mapping:ffff88813bff0640 index:0xffff88809d630e40 flags: 0xfff00000000100(slab) raw: 00fff00000000100 ffffea000268edc8 ffffea0002508988 ffff88813bff0640 raw: ffff88809d630e40 ffff88809d630000 0000000100000013 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809d630c80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ffff88809d630d00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff88809d630d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88809d630e00: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ffff88809d630e80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ==================================================================