syzbot

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 1 UID: 0 PID: 798 Comm: kworker/1:2 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: events vidtv_mux_tick
RIP: 0010:vidtv_psi_ts_psi_write_into+0x54a/0xbc0 drivers/media/test-drivers/vidtv/vidtv_psi.c:197
Code: 3c a2 dc f9 4c 8d 63 20 4c 89 e0 48 c1 e8 03 80 3c 28 00 0f 85 e8 04 00 00 48 8b 43 20 48 89 c2 48 89 c1 48 c1 ea 03 83 e1 07 <0f> b6 14 2a 38 ca 7f 08 84 d2 0f 85 19 05 00 00 0f b6 10 48 8b 7c
RSP: 0018:ffffc900043573f8 EFLAGS: 00010202
RAX: 0000000000000002 RBX: ffffc90004357678 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffffff882b5864 RDI: ffff8880273b0000
RBP: dffffc0000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffc90004357698
R13: 0000000000000178 R14: 0000000000000000 R15: 0000000000000008
FS:  0000000000000000(0000) GS:ffff88812444e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3420bff8 CR3: 000000007e770000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 vidtv_psi_table_header_write_into drivers/media/test-drivers/vidtv/vidtv_psi.c:799 [inline]
 vidtv_psi_pmt_write_into+0x3b2/0xa70 drivers/media/test-drivers/vidtv/vidtv_psi.c:1231
 vidtv_mux_push_si+0x932/0xe80 drivers/media/test-drivers/vidtv/vidtv_mux.c:196
 vidtv_mux_tick+0xe9b/0x1480 drivers/media/test-drivers/vidtv/vidtv_mux.c:408
 process_one_work+0x9d7/0x1920 kernel/workqueue.c:3275
 process_scheduled_works kernel/workqueue.c:3358 [inline]
 worker_thread+0x5da/0xe40 kernel/workqueue.c:3439
 kthread+0x370/0x450 kernel/kthread.c:467
 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:vidtv_psi_ts_psi_write_into+0x54a/0xbc0 drivers/media/test-drivers/vidtv/vidtv_psi.c:197
Code: 3c a2 dc f9 4c 8d 63 20 4c 89 e0 48 c1 e8 03 80 3c 28 00 0f 85 e8 04 00 00 48 8b 43 20 48 89 c2 48 89 c1 48 c1 ea 03 83 e1 07 <0f> b6 14 2a 38 ca 7f 08 84 d2 0f 85 19 05 00 00 0f b6 10 48 8b 7c
RSP: 0018:ffffc900043573f8 EFLAGS: 00010202
RAX: 0000000000000002 RBX: ffffc90004357678 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffffff882b5864 RDI: ffff8880273b0000
RBP: dffffc0000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffc90004357698
R13: 0000000000000178 R14: 0000000000000000 R15: 0000000000000008
FS:  0000000000000000(0000) GS:ffff88812444e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b307fbff8 CR3: 00000000347a2000 CR4: 00000000003526f0
----------------
Code disassembly (best guess):
   0:	3c a2                	cmp    $0xa2,%al
   2:	dc f9                	fdivr  %st,%st(1)
   4:	4c 8d 63 20          	lea    0x20(%rbx),%r12
   8:	4c 89 e0             	mov    %r12,%rax
   b:	48 c1 e8 03          	shr    $0x3,%rax
   f:	80 3c 28 00          	cmpb   $0x0,(%rax,%rbp,1)
  13:	0f 85 e8 04 00 00    	jne    0x501
  19:	48 8b 43 20          	mov    0x20(%rbx),%rax
  1d:	48 89 c2             	mov    %rax,%rdx
  20:	48 89 c1             	mov    %rax,%rcx
  23:	48 c1 ea 03          	shr    $0x3,%rdx
  27:	83 e1 07             	and    $0x7,%ecx
* 2a:	0f b6 14 2a          	movzbl (%rdx,%rbp,1),%edx <-- trapping instruction
  2e:	38 ca                	cmp    %cl,%dl
  30:	7f 08                	jg     0x3a
  32:	84 d2                	test   %dl,%dl
  34:	0f 85 19 05 00 00    	jne    0x553
  3a:	0f b6 10             	movzbl (%rax),%edx
  3d:	48                   	rex.W
  3e:	8b                   	.byte 0x8b
  3f:	7c                   	.byte 0x7c