Bluetooth: hci0: sending frame failed (-49)
Bluetooth: hci0: command 0x1001 tx timeout
Bluetooth: hci0: sending frame failed (-49)
Bluetooth: hci0: command 0x1009 tx timeout
==================================================================
BUG: KASAN: use-after-free in atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
BUG: KASAN: use-after-free in refcount_read include/linux/refcount.h:43 [inline]
BUG: KASAN: use-after-free in skb_unref include/linux/skbuff.h:967 [inline]
BUG: KASAN: use-after-free in kfree_skb+0x38/0x390 net/core/skbuff.c:659
Read of size 4 at addr ffff88808e2817a4 by task syz-executor.2/27570

CPU: 0 PID: 27570 Comm: syz-executor.2 Not tainted 4.19.80 #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+0x172/0x1f0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report mm/kasan/report.c:412 [inline]
 kasan_report.cold+0x8c/0x2ba mm/kasan/report.c:396
 check_memory_region_inline mm/kasan/kasan.c:260 [inline]
 check_memory_region+0x123/0x190 mm/kasan/kasan.c:267
 kasan_check_read+0x11/0x20 mm/kasan/kasan.c:272
 atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
 refcount_read include/linux/refcount.h:43 [inline]
 skb_unref include/linux/skbuff.h:967 [inline]
 kfree_skb+0x38/0x390 net/core/skbuff.c:659
 bcsp_close+0xc7/0x130 drivers/bluetooth/hci_bcsp.c:763
 hci_uart_tty_close+0x1ea/0x250 drivers/bluetooth/hci_ldisc.c:555
 tty_ldisc_close.isra.0+0xaf/0xe0 drivers/tty/tty_ldisc.c:486
 tty_ldisc_kill+0x4b/0xc0 drivers/tty/tty_ldisc.c:632
 tty_ldisc_release+0xc6/0x280 drivers/tty/tty_ldisc.c:799
 tty_release_struct+0x1b/0x50 drivers/tty/tty_io.c:1611
 tty_release+0xbcb/0xe90 drivers/tty/tty_io.c:1784
 __fput+0x2dd/0x8b0 fs/file_table.c:278
 ____fput+0x16/0x20 fs/file_table.c:309
 task_work_run+0x145/0x1c0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:193 [inline]
 exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:167
 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
 do_syscall_64+0x53d/0x620 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x413a91
Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 04 1b 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00007fff71cde0d0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000413a91
RDX: 0000001b32f20000 RSI: 0000000000000a6b RDI: 0000000000000003
RBP: 0000000000000001 R08: 00000000d0bf8a6b R09: 00000000d0bf8a6f
R10: 00007fff71cde1b0 R11: 0000000000000293 R12: 000000000075c9a0
R13: 000000000075c9a0 R14: 0000000000760518 R15: 000000000075bfd4

Allocated by task 34:
 save_stack+0x45/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc mm/kasan/kasan.c:553 [inline]
 kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:531
 kasan_slab_alloc+0xf/0x20 mm/kasan/kasan.c:490
 kmem_cache_alloc_node+0x144/0x710 mm/slab.c:3649
 __alloc_skb+0xd5/0x5f0 net/core/skbuff.c:193
 alloc_skb include/linux/skbuff.h:995 [inline]
 bt_skb_alloc include/net/bluetooth/bluetooth.h:339 [inline]
 bcsp_recv+0x8c7/0x13a0 drivers/bluetooth/hci_bcsp.c:685
 hci_uart_tty_receive+0x225/0x530 drivers/bluetooth/hci_ldisc.c:620
 tty_ldisc_receive_buf+0x15f/0x1c0 drivers/tty/tty_buffer.c:460
 tty_port_default_receive_buf+0x7d/0xb0 drivers/tty/tty_port.c:38
 receive_buf drivers/tty/tty_buffer.c:476 [inline]
 flush_to_ldisc+0x222/0x390 drivers/tty/tty_buffer.c:528
 process_one_work+0x989/0x1750 kernel/workqueue.c:2153
 worker_thread+0x98/0xe40 kernel/workqueue.c:2296
 kthread+0x354/0x420 kernel/kthread.c:246
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

Freed by task 34:
 save_stack+0x45/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3503 [inline]
 kmem_cache_free+0x86/0x260 mm/slab.c:3765
 kfree_skbmem net/core/skbuff.c:586 [inline]
 kfree_skbmem+0xcb/0x150 net/core/skbuff.c:580
 __kfree_skb net/core/skbuff.c:646 [inline]
 kfree_skb net/core/skbuff.c:663 [inline]
 kfree_skb+0xf0/0x390 net/core/skbuff.c:657
 bcsp_recv+0x2d8/0x13a0 drivers/bluetooth/hci_bcsp.c:623
 hci_uart_tty_receive+0x225/0x530 drivers/bluetooth/hci_ldisc.c:620
 tty_ldisc_receive_buf+0x15f/0x1c0 drivers/tty/tty_buffer.c:460
 tty_port_default_receive_buf+0x7d/0xb0 drivers/tty/tty_port.c:38
 receive_buf drivers/tty/tty_buffer.c:476 [inline]
 flush_to_ldisc+0x222/0x390 drivers/tty/tty_buffer.c:528
 process_one_work+0x989/0x1750 kernel/workqueue.c:2153
 worker_thread+0x98/0xe40 kernel/workqueue.c:2296
 kthread+0x354/0x420 kernel/kthread.c:246
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

The buggy address belongs to the object at ffff88808e2816c0
 which belongs to the cache skbuff_head_cache of size 232
The buggy address is located 228 bytes inside of
 232-byte region [ffff88808e2816c0, ffff88808e2817a8)
The buggy address belongs to the page:
page:ffffea000238a040 count:1 mapcount:0 mapping:ffff8880aa33cac0 index:0xffff88808e281580
flags: 0x1fffc0000000100(slab)
raw: 01fffc0000000100 ffffea00022251c8 ffffea00024b0a08 ffff8880aa33cac0
raw: ffff88808e281580 ffff88808e281080 0000000100000003 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88808e281680: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
 ffff88808e281700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88808e281780: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc
                               ^
 ffff88808e281800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88808e281880: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc
==================================================================