syzbot


general protection fault in dvb_usbv2_generic_write

Status: upstream: reported C repro on 2025/12/25 21:19
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+d8d2dbd2f2120bdaab41@syzkaller.appspotmail.com
First crash: 19d, last: 19d
Bug presence (1)
Date Name Commit Repro Result
2025/12/26 upstream (ToT) ccd1cdca5cd4 C [report] general protection fault in dvb_usbv2_generic_write
Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 general protection fault in dvb_usbv2_generic_write origin:upstream 2 C 25 11h48m 80d 0/3 upstream: reported C repro on 2025/10/25 16:29
upstream general protection fault in dvb_usbv2_generic_write usb media 2 C error 105 1h19m 487d 0/29 upstream: reported C repro on 2024/09/13 13:35
linux-6.1 general protection fault in dvb_usbv2_generic_write 2 1 279d 279d 0/3 auto-obsoleted due to no activity on 2025/07/18 07:04
linux-6.1 general protection fault in dvb_usbv2_generic_write (2) origin:upstream 2 C 3 19d 19d 0/3 upstream: reported C repro on 2025/12/25 21:19

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc0000000019: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000000c8-0x00000000000000cf]
CPU: 0 PID: 5964 Comm: syz.2.23 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:582 [inline]
RIP: 0010:__mutex_lock+0xe5/0xcc0 kernel/locking/mutex.c:747
Code: 0f b6 04 30 84 c0 0f 85 da 0a 00 00 83 3d d2 a1 79 0c 00 75 2a 48 8d 7b 60 48 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 05 e8 e0 eb 6c f7 48 39 5b 60 0f 85 44 0a 00 00 bf
RSP: 0018:ffffc900035173c0 EFLAGS: 00010202
RAX: 0000000000000019 RBX: 0000000000000068 RCX: dffffc0000000000
RDX: ffff88802ad0bc00 RSI: ffffffff8aaace60 RDI: 00000000000000c8
RBP: ffffc90003517518 R08: ffffffff87064df6 R09: 000000000000001e
R10: dffffc0000000000 R11: ffffed100bcde42c R12: 0000000000000000
R13: 1ffff920006a2e88 R14: dffffc0000000000 R15: 0000000000000000
FS:  00005555743b2500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b34763fff CR3: 000000007c789000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 dvb_usbv2_generic_write+0x26/0x50 drivers/media/usb/dvb-usb-v2/dvb_usb_urb.c:77
 mxl111sf_ctrl_msg+0x162/0x2d0 drivers/media/usb/dvb-usb-v2/mxl111sf.c:73
 mxl111sf_write_reg+0xa1/0x180 drivers/media/usb/dvb-usb-v2/mxl111sf.c:123
 mxl111sf_i2c_start drivers/media/usb/dvb-usb-v2/mxl111sf-i2c.c:130 [inline]
 mxl111sf_i2c_sw_xfer_msg drivers/media/usb/dvb-usb-v2/mxl111sf-i2c.c:-1 [inline]
 mxl111sf_i2c_xfer+0x462/0x4ed0 drivers/media/usb/dvb-usb-v2/mxl111sf-i2c.c:813
 __i2c_transfer+0x868/0x2080 drivers/i2c/i2c-core-base.c:-1
 i2c_transfer+0x250/0x390 drivers/i2c/i2c-core-base.c:2328
 i2cdev_ioctl_rdwr+0x3b0/0x690 drivers/i2c/i2c-dev.c:297
 i2cdev_ioctl+0x646/0x7e0 drivers/i2c/i2c-dev.c:458
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f7ba778f749
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff1f937938 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f7ba79e5fa0 RCX: 00007f7ba778f749
RDX: 0000200000000a40 RSI: 0000000000000707 RDI: 0000000000000004
RBP: 00007f7ba7813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7ba79e5fa0 R14: 00007f7ba79e5fa0 R15: 0000000000000003
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:582 [inline]
RIP: 0010:__mutex_lock+0xe5/0xcc0 kernel/locking/mutex.c:747
Code: 0f b6 04 30 84 c0 0f 85 da 0a 00 00 83 3d d2 a1 79 0c 00 75 2a 48 8d 7b 60 48 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 05 e8 e0 eb 6c f7 48 39 5b 60 0f 85 44 0a 00 00 bf
RSP: 0018:ffffc900035173c0 EFLAGS: 00010202
RAX: 0000000000000019 RBX: 0000000000000068 RCX: dffffc0000000000
RDX: ffff88802ad0bc00 RSI: ffffffff8aaace60 RDI: 00000000000000c8
RBP: ffffc90003517518 R08: ffffffff87064df6 R09: 000000000000001e
R10: dffffc0000000000 R11: ffffed100bcde42c R12: 0000000000000000
R13: 1ffff920006a2e88 R14: dffffc0000000000 R15: 0000000000000000
FS:  00005555743b2500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6c4e9135c0 CR3: 000000007c789000 CR4: 00000000003506e0
----------------
Code disassembly (best guess):
   0:	0f b6 04 30          	movzbl (%rax,%rsi,1),%eax
   4:	84 c0                	test   %al,%al
   6:	0f 85 da 0a 00 00    	jne    0xae6
   c:	83 3d d2 a1 79 0c 00 	cmpl   $0x0,0xc79a1d2(%rip)        # 0xc79a1e5
  13:	75 2a                	jne    0x3f
  15:	48 8d 7b 60          	lea    0x60(%rbx),%rdi
  19:	48 89 f8             	mov    %rdi,%rax
  1c:	48 c1 e8 03          	shr    $0x3,%rax
  20:	48 b9 00 00 00 00 00 	movabs $0xdffffc0000000000,%rcx
  27:	fc ff df
* 2a:	80 3c 08 00          	cmpb   $0x0,(%rax,%rcx,1) <-- trapping instruction
  2e:	74 05                	je     0x35
  30:	e8 e0 eb 6c f7       	call   0xf76cec15
  35:	48 39 5b 60          	cmp    %rbx,0x60(%rbx)
  39:	0f 85 44 0a 00 00    	jne    0xa83
  3f:	bf                   	.byte 0xbf

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/25 21:52 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan general protection fault in dvb_usbv2_generic_write
2025/12/25 21:21 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan general protection fault in dvb_usbv2_generic_write
2025/12/25 21:19 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan general protection fault in dvb_usbv2_generic_write
* Struck through repros no longer work on HEAD.