kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xc3/0x120 net/socket.c:661
CPU: 0 PID: 9436 Comm: kworker/u4:5 Not tainted 4.19.204-syzkaller #0
 ___sys_sendmsg+0x3b3/0x8e0 net/socket.c:2225
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_unbound flush_to_ldisc
RIP: 0010:skb_tail_pointer include/linux/skbuff.h:2048 [inline]
RIP: 0010:skb_put+0x2b/0x190 net/core/skbuff.c:1706
Code: 56 41 55 41 54 41 89 f4 55 48 89 fd 53 e8 cd 43 f2 fa 48 8d bd d0 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 43 01 00 00 48 8d bd c8 00 00 00 4c 8b ad d0 00
RSP: 0018:ffff888044f1fad8 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8880b13d62c0 RCX: ffffffff85d23870
RDX: 000000000000001a RSI: ffffffff86704ec3 RDI: 00000000000000d0
RBP: 0000000000000000 R08: 0000000000000000 R09: 00000000000000db
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001
R13: 000000000000000a R14: ffff8880b13d63b8 R15: ffff8880b13d641c
FS:  0000000000000000(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
 __sys_sendmmsg+0x195/0x470 net/socket.c:2320
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055a500a368b8 CR3: 00000000a869e000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 skb_put_data include/linux/skbuff.h:2128 [inline]
 bcsp_unslip_one_byte drivers/bluetooth/hci_bcsp.c:451 [inline]
 bcsp_recv+0x948/0x1550 drivers/bluetooth/hci_bcsp.c:613
 hci_uart_tty_receive+0x221/0x530 drivers/bluetooth/hci_ldisc.c:621
 __do_sys_sendmmsg net/socket.c:2349 [inline]
 __se_sys_sendmmsg net/socket.c:2346 [inline]
 __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2346
 tty_ldisc_receive_buf+0x14a/0x190 drivers/tty/tty_buffer.c:460
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 tty_port_default_receive_buf+0x78/0xa0 drivers/tty/tty_port.c:38
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
 receive_buf drivers/tty/tty_buffer.c:476 [inline]
 flush_to_ldisc+0x21f/0x390 drivers/tty/tty_buffer.c:528
RIP: 0033:0x4665e9
 process_one_work+0x864/0x1570 kernel/workqueue.c:2153
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:00007fcafe88d188 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296
RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665e9
RDX: 03fffffffffffe36 RSI: 0000000020001e00 RDI: 0000000000000003
 kthread+0x33f/0x460 kernel/kthread.c:259
RBP: 00007fcafe88d1d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fff776a90df R14: 00007fcafe88d300 R15: 0000000000022000
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Bluetooth: Error in BCSP hdr checksum
Modules linked in:
Bluetooth: Error in BCSP hdr checksum
Bluetooth: Error in BCSP hdr checksum
Bluetooth: Error in BCSP hdr checksum
Bluetooth: Error in BCSP hdr checksum
Bluetooth: Error in BCSP hdr checksum
Bluetooth: Can't allocate mem for new packet
---[ end trace 573da2ae407acb32 ]---
RIP: 0010:skb_tail_pointer include/linux/skbuff.h:2048 [inline]
RIP: 0010:skb_put+0x2b/0x190 net/core/skbuff.c:1706
Code: 56 41 55 41 54 41 89 f4 55 48 89 fd 53 e8 cd 43 f2 fa 48 8d bd d0 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 43 01 00 00 48 8d bd c8 00 00 00 4c 8b ad d0 00
RSP: 0018:ffff888044f1fad8 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8880b13d62c0 RCX: ffffffff85d23870
RDX: 000000000000001a RSI: ffffffff86704ec3 RDI: 00000000000000d0
RBP: 0000000000000000 R08: 0000000000000000 R09: 00000000000000db
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001
R13: 000000000000000a R14: ffff8880b13d63b8 R15: ffff8880b13d641c
FS:  0000000000000000(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
Bluetooth: Error in BCSP hdr checksum
Bluetooth: Error in BCSP hdr checksum
Bluetooth: Error in BCSP hdr checksum
Bluetooth: Error in BCSP hdr checksum
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2ef14d5000 CR3: 00000000a869e000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	56                   	push   %rsi
   1:	41 55                	push   %r13
   3:	41 54                	push   %r12
   5:	41 89 f4             	mov    %esi,%r12d
   8:	55                   	push   %rbp
   9:	48 89 fd             	mov    %rdi,%rbp
   c:	53                   	push   %rbx
   d:	e8 cd 43 f2 fa       	callq  0xfaf243df
  12:	48 8d bd d0 00 00 00 	lea    0xd0(%rbp),%rdi
  19:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  20:	fc ff df 
  23:	48 89 fa             	mov    %rdi,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
  2a:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
  2e:	0f 85 43 01 00 00    	jne    0x177
  34:	48 8d bd c8 00 00 00 	lea    0xc8(%rbp),%rdi
  3b:	4c                   	rex.WR
  3c:	8b                   	.byte 0x8b
  3d:	ad                   	lods   %ds:(%rsi),%eax
  3e:	d0 00                	rolb   (%rax)