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BUG: KASAN: double-free or invalid-free in skb_free_head+0x6e/0x90 net/core/skbuff.c:589

CPU: 1 PID: 7521 Comm: syz-executor.4 Not tainted 5.2.0-rc6+ #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+0x113/0x167 lib/dump_stack.c:113
 print_address_description.cold.5+0x9/0x1ff mm/kasan/report.c:188
 kasan_report_invalid_free+0x64/0xa0 mm/kasan/report.c:279
 __kasan_slab_free+0x13a/0x150 mm/kasan/common.c:430
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:459
 __cache_free mm/slab.c:3432 [inline]
 kfree+0xcf/0x220 mm/slab.c:3755
 skb_free_head+0x6e/0x90 net/core/skbuff.c:589
 skb_release_data+0x376/0x6a0 net/core/skbuff.c:609
 skb_release_all+0x3d/0x50 net/core/skbuff.c:663
 __kfree_skb net/core/skbuff.c:677 [inline]
 kfree_skb+0x97/0x270 net/core/skbuff.c:695
 bcsp_close+0xb5/0x120 drivers/bluetooth/hci_bcsp.c:748
 hci_uart_tty_close+0x18f/0x1f0 drivers/bluetooth/hci_ldisc.c:535
 tty_ldisc_close.isra.3+0xc8/0x120 drivers/tty/tty_ldisc.c:494
 tty_ldisc_kill+0x7f/0x120 drivers/tty/tty_ldisc.c:642
 tty_ldisc_release+0xb8/0x1a0 drivers/tty/tty_ldisc.c:814
 tty_release_struct+0x12/0x50 drivers/tty/tty_io.c:1612
 tty_release+0x97e/0xc60 drivers/tty/tty_io.c:1785
 __fput+0x25a/0x770 fs/file_table.c:280
 ____fput+0x9/0x10 fs/file_table.c:313
 task_work_run+0x108/0x180 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:185 [inline]
 exit_to_usermode_loop+0x1a9/0x200 arch/x86/entry/common.c:168
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:279 [inline]
 do_syscall_64+0x447/0x530 arch/x86/entry/common.c:304
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x413ae1
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:00007ffc4057d0e0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000006 RCX: 0000000000413ae1
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 0000000000000001 R08: ffffffffffffffff R09: ffffffffffffffff
R10: 00007ffc4057d1c0 R11: 0000000000000293 R12: 000000000075c9a0
R13: 000000000075c9a0 R14: 00000000007602d8 R15: 000000000075bfd4

Allocated by task 91:
 save_stack+0x21/0x90 mm/kasan/common.c:71
 set_track mm/kasan/common.c:79 [inline]
 __kasan_kmalloc.constprop.8+0xc7/0xd0 mm/kasan/common.c:489
 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:503
 __do_kmalloc_node mm/slab.c:3620 [inline]
 __kmalloc_node_track_caller+0x4d/0x70 mm/slab.c:3634
 __kmalloc_reserve.isra.38+0x2c/0xc0 net/core/skbuff.c:139
 __alloc_skb+0xd7/0x570 net/core/skbuff.c:207
 alloc_skb include/linux/skbuff.h:1054 [inline]
 bt_skb_alloc include/net/bluetooth/bluetooth.h:339 [inline]
 bcsp_recv+0x351/0x1480 drivers/bluetooth/hci_bcsp.c:670
 hci_uart_tty_receive+0x1ce/0x460 drivers/bluetooth/hci_ldisc.c:600
 tty_ldisc_receive_buf+0xff/0x1b0 drivers/tty/tty_buffer.c:465
 tty_port_default_receive_buf+0x5f/0x90 drivers/tty/tty_port.c:38
 receive_buf drivers/tty/tty_buffer.c:481 [inline]
 flush_to_ldisc+0x1aa/0x3a0 drivers/tty/tty_buffer.c:533
 process_one_work+0x830/0x16a0 kernel/workqueue.c:2269
 worker_thread+0x85/0xb60 kernel/workqueue.c:2415
 kthread+0x324/0x3e0 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

Freed by task 91:
 save_stack+0x21/0x90 mm/kasan/common.c:71
 set_track mm/kasan/common.c:79 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:451
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:459
 __cache_free mm/slab.c:3432 [inline]
 kfree+0xcf/0x220 mm/slab.c:3755
 skb_free_head+0x6e/0x90 net/core/skbuff.c:589
 skb_release_data+0x376/0x6a0 net/core/skbuff.c:609
 skb_release_all+0x3d/0x50 net/core/skbuff.c:663
 __kfree_skb net/core/skbuff.c:677 [inline]
 kfree_skb+0x97/0x270 net/core/skbuff.c:695
 bcsp_recv+0x260/0x1480 drivers/bluetooth/hci_bcsp.c:608
 hci_uart_tty_receive+0x1ce/0x460 drivers/bluetooth/hci_ldisc.c:600
 tty_ldisc_receive_buf+0xff/0x1b0 drivers/tty/tty_buffer.c:465
 tty_port_default_receive_buf+0x5f/0x90 drivers/tty/tty_port.c:38
 receive_buf drivers/tty/tty_buffer.c:481 [inline]
 flush_to_ldisc+0x1aa/0x3a0 drivers/tty/tty_buffer.c:533
 process_one_work+0x830/0x16a0 kernel/workqueue.c:2269
 worker_thread+0x85/0xb60 kernel/workqueue.c:2415
 kthread+0x324/0x3e0 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

The buggy address belongs to the object at ffff8880a0015100
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 0 bytes inside of
 8192-byte region [ffff8880a0015100, ffff8880a0017100)
The buggy address belongs to the page:
page:ffffea0002800500 refcount:1 mapcount:0 mapping:ffff8880aa402080 index:0x0 compound_mapcount: 0
flags: 0x1fffc0000010200(slab|head)
raw: 01fffc0000010200 ffffea000224cb08 ffffea00022aa508 ffff8880aa402080
raw: 0000000000000000 ffff8880a0015100 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880a0015000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880a0015080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880a0015100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff8880a0015180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880a0015200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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