syzbot

Oops: general protection fault, probably for non-canonical address 0xdffffc000000044c: 0000 [#1] SMP KASAN NOPTI
KASAN: probably user-memory-access in range [0x0000000000002260-0x0000000000002267]
CPU: 1 UID: 0 PID: 13 Comm: kworker/u8:1 Not tainted 6.15.0-rc5-syzkaller-00043-gd76bb1ebb558 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
Workqueue: events_unbound flush_to_ldisc
RIP: 0010:n_tty_receive_buf_common+0xf3/0x1980 drivers/tty/n_tty.c:1702
Code: 00 00 00 00 00 00 00 48 89 7c 24 68 48 89 4c 24 70 89 9c 24 94 00 00 00 48 89 84 24 a0 00 00 00 e8 32 3d 75 fc 48 8b 44 24 68 <80> 38 00 0f 85 b6 15 00 00 48 8b 44 24 18 48 8b a8 60 22 00 00 48
RSP: 0018:ffffc90000127a70 EFLAGS: 00010293
RAX: dffffc000000044c RBX: 0000000000000001 RCX: dffffc0000000000
RDX: ffff88801ca80000 RSI: ffffffff8545f5be RDI: dffffc000000044c
RBP: 00000000000001fc R08: 0000000000000001 R09: ffffed1005013650
R10: ffff88802809b287 R11: 0000000000000000 R12: ffff88802e5f4824
R13: 0000000000000000 R14: ffff88802809b000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888124adf000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2dedaff8 CR3: 0000000025a85000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 tty_ldisc_receive_buf+0xa7/0x1a0 drivers/tty/tty_buffer.c:387
 tty_port_default_receive_buf+0x70/0xb0 drivers/tty/tty_port.c:37
 receive_buf drivers/tty/tty_buffer.c:445 [inline]
 flush_to_ldisc+0x268/0x780 drivers/tty/tty_buffer.c:495
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:n_tty_receive_buf_common+0xf3/0x1980 drivers/tty/n_tty.c:1702
Code: 00 00 00 00 00 00 00 48 89 7c 24 68 48 89 4c 24 70 89 9c 24 94 00 00 00 48 89 84 24 a0 00 00 00 e8 32 3d 75 fc 48 8b 44 24 68 <80> 38 00 0f 85 b6 15 00 00 48 8b 44 24 18 48 8b a8 60 22 00 00 48
RSP: 0018:ffffc90000127a70 EFLAGS: 00010293
RAX: dffffc000000044c RBX: 0000000000000001 RCX: dffffc0000000000
RDX: ffff88801ca80000 RSI: ffffffff8545f5be RDI: dffffc000000044c
RBP: 00000000000001fc R08: 0000000000000001 R09: ffffed1005013650
R10: ffff88802809b287 R11: 0000000000000000 R12: ffff88802e5f4824
R13: 0000000000000000 R14: ffff88802809b000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888124adf000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2dedaff8 CR3: 000000000e180000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	00 00                	add    %al,(%rax)
   4:	00 00                	add    %al,(%rax)
   6:	00 48 89             	add    %cl,-0x77(%rax)
   9:	7c 24                	jl     0x2f
   b:	68 48 89 4c 24       	push   $0x244c8948
  10:	70 89                	jo     0xffffff9b
  12:	9c                   	pushf
  13:	24 94                	and    $0x94,%al
  15:	00 00                	add    %al,(%rax)
  17:	00 48 89             	add    %cl,-0x77(%rax)
  1a:	84 24 a0             	test   %ah,(%rax,%riz,4)
  1d:	00 00                	add    %al,(%rax)
  1f:	00 e8                	add    %ch,%al
  21:	32 3d 75 fc 48 8b    	xor    -0x74b7038b(%rip),%bh        # 0x8b48fc9c
  27:	44 24 68             	rex.R and $0x68,%al
* 2a:	80 38 00             	cmpb   $0x0,(%rax) <-- trapping instruction
  2d:	0f 85 b6 15 00 00    	jne    0x15e9
  33:	48 8b 44 24 18       	mov    0x18(%rsp),%rax
  38:	48 8b a8 60 22 00 00 	mov    0x2260(%rax),%rbp
  3f:	48                   	rex.W