================================================================== BUG: KASAN: use-after-free in hci_chan_del+0x1a7/0x1e0 net/bluetooth/hci_conn.c:1564 Read of size 8 at addr ffff8880b416c3d8 by task syz-executor.3/6251 CPU: 0 PID: 6251 Comm: syz-executor.3 Not tainted 4.14.206-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x283 lib/dump_stack.c:58 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252 kasan_report_error.cold+0x8a/0x194 mm/kasan/report.c:351 kasan_report mm/kasan/report.c:409 [inline] __asan_report_load8_noabort+0x68/0x70 mm/kasan/report.c:430 hci_chan_del+0x1a7/0x1e0 net/bluetooth/hci_conn.c:1564 l2cap_conn_del+0x426/0x690 net/bluetooth/l2cap_core.c:1739 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7441 [inline] l2cap_disconn_cfm+0x7c/0xb0 net/bluetooth/l2cap_core.c:7434 hci_disconn_cfm include/net/bluetooth/hci_core.h:1226 [inline] hci_conn_hash_flush+0x127/0x260 net/bluetooth/hci_conn.c:1393 hci_dev_do_close+0x535/0xca0 net/bluetooth/hci_core.c:1620 hci_rfkill_set_block+0xaf/0x120 net/bluetooth/hci_core.c:2050 rfkill_set_block+0x1b2/0x4a0 net/rfkill/core.c:337 rfkill_fop_write+0x1b6/0x3c0 net/rfkill/core.c:1233 __vfs_write+0xe4/0x630 fs/read_write.c:480 vfs_write+0x17f/0x4d0 fs/read_write.c:544 SYSC_write fs/read_write.c:590 [inline] SyS_write+0xf2/0x210 fs/read_write.c:582 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x45deb9 RSP: 002b:00007fef6cbf0c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000003af80 RCX: 000000000045deb9 RDX: 0000000000000008 RSI: 0000000020000040 RDI: 0000000000000003 RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c R13: 00007ffc5b0b891f R14: 00007fef6cbf19c0 R15: 000000000118bf2c Allocated by task 8065: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:551 kmem_cache_alloc_trace+0x131/0x3d0 mm/slab.c:3618 kmalloc include/linux/slab.h:488 [inline] kzalloc include/linux/slab.h:661 [inline] hci_chan_create+0x8b/0x3a0 net/bluetooth/hci_conn.c:1549 l2cap_conn_add.part.0+0x18/0xc30 net/bluetooth/l2cap_core.c:7062 l2cap_conn_add include/net/bluetooth/l2cap.h:811 [inline] l2cap_connect_cfm+0x526/0xdb0 net/bluetooth/l2cap_core.c:7379 hci_connect_cfm include/net/bluetooth/hci_core.h:1211 [inline] hci_le_conn_complete_evt net/bluetooth/hci_event.c:4601 [inline] hci_le_meta_evt+0x3634/0x43c0 net/bluetooth/hci_event.c:5169 hci_event_packet+0x2217/0x750f net/bluetooth/hci_event.c:5429 hci_rx_work+0x427/0xb40 net/bluetooth/hci_core.c:4244 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Freed by task 8071: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0xc3/0x1a0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kfree+0xc9/0x250 mm/slab.c:3815 hci_disconn_loglink_complete_evt.isra.0+0x1c1/0x230 net/bluetooth/hci_event.c:4432 hci_event_packet+0x3444/0x750f net/bluetooth/hci_event.c:5450 hci_rx_work+0x427/0xb40 net/bluetooth/hci_core.c:4244 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 The buggy address belongs to the object at ffff8880b416c3c0 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 24 bytes inside of 128-byte region [ffff8880b416c3c0, ffff8880b416c440) The buggy address belongs to the page: page:ffffea0002d05b00 count:1 mapcount:0 mapping:ffff8880b416c000 index:0xffff8880b416c840 flags: 0xfff00000000100(slab) raw: 00fff00000000100 ffff8880b416c000 ffff8880b416c840 0000000100000013 raw: ffffea0002766d60 ffffea0002beb360 ffff88813fe82640 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880b416c280: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc ffff8880b416c300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8880b416c380: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ^ ffff8880b416c400: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880b416c480: 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc ================================================================== Context (ID=0x10) not attached to queue pair (handle=0xffffffff:0x0) Context (ID=0x10) not attached to queue pair (handle=0xffffffff:0x0)