Re: [syzbot] [usb?] general protection fault in wcove_typec_probe

From: syzbot

Date: Mon Aug 24 2026 - 23:46:43 EST


syzbot has found a reproducer for the following issue on:

HEAD commit: 66498c75b4f8 Merge tag 'dmaengine-7.3-rc1' of git://git.ke..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1253719e580000
kernel config: https://syzkaller.appspot.com/x/.config?x=3e64b1bf01d830ed
dashboard link: https://syzkaller.appspot.com/bug?extid=1a01783ea233350598b5
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
userspace arch: i386
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17491979580000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-66498c75.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5ce4685e13ba/vmlinux-66498c75.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6a32d8e997a7/bzImage-66498c75.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1a01783ea233350598b5@xxxxxxxxxxxxxxxxxxxxxxxxx

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 0 UID: 0 PID: 5912 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:wcove_typec_probe+0xdb/0x780 drivers/usb/typec/tcpm/wcove.c:621
Code: 48 c1 ea 03 80 3c 02 00 0f 85 af 05 00 00 48 8d 7d 08 4d 89 af 88 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 7f 05 00 00 49 8d bf 90 00 00 00 48 8b 6d 08 48
RSP: 0018:ffffc90002f6faf8 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8880226c1000 RCX: 0000000000000000
RDX: 0000000000000001 RSI: 0000000000000001 RDI: 0000000000000008
RBP: 0000000000000000 R08: 0000000000000004 R09: 0000000000000000
R10: ffff888014243883 R11: 000000000000001f R12: ffffffff904a7ea8
R13: ffff8880226c1010 R14: ffff8880142438c0 R15: ffff888014243838
FS: 0000000000000000(0000) GS:ffff888096982000(0063) knlGS:00000000f67e5b40
CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000032e24008 CR3: 000000004e2f1000 CR4: 0000000000352ef0
Call Trace:
<TASK>
platform_probe+0x106/0x1d0 drivers/base/platform.c:1507
call_driver_probe drivers/base/dd.c:628 [inline]
really_probe+0x241/0xa60 drivers/base/dd.c:706
__driver_probe_device+0x210/0x460 drivers/base/dd.c:868
device_driver_attach+0xd1/0x220 drivers/base/dd.c:1203
bind_store+0xf4/0x190 drivers/base/bus.c:267
drv_attr_store+0x74/0xb0 drivers/base/bus.c:125
sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:145
kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:345
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6af/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:79 [inline]
__do_fast_syscall_32+0x13a/0x8b0 arch/x86/entry/syscall_32.c:291
do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:316
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf6feefec
Code: Unable to access opcode bytes at 0xf6feefc2.
RSP: 002b:00000000f67e550c EFLAGS: 00000292 ORIG_RAX: 0000000000000004
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000080000400
RDX: 0000000000000007 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:wcove_typec_probe+0xdb/0x780 drivers/usb/typec/tcpm/wcove.c:621
Code: 48 c1 ea 03 80 3c 02 00 0f 85 af 05 00 00 48 8d 7d 08 4d 89 af 88 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 7f 05 00 00 49 8d bf 90 00 00 00 48 8b 6d 08 48
RSP: 0018:ffffc90002f6faf8 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8880226c1000 RCX: 0000000000000000
RDX: 0000000000000001 RSI: 0000000000000001 RDI: 0000000000000008
RBP: 0000000000000000 R08: 0000000000000004 R09: 0000000000000000
R10: ffff888014243883 R11: 000000000000001f R12: ffffffff904a7ea8
R13: ffff8880226c1010 R14: ffff8880142438c0 R15: ffff888014243838
FS: 0000000000000000(0000) GS:ffff888096a82000(0063) knlGS:00000000f67e5b40
CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00007f45dd833708 CR3: 000000004e2f1000 CR4: 0000000000352ef0
----------------
Code disassembly (best guess):
0: 48 c1 ea 03 shr $0x3,%rdx
4: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1)
8: 0f 85 af 05 00 00 jne 0x5bd
e: 48 8d 7d 08 lea 0x8(%rbp),%rdi
12: 4d 89 af 88 00 00 00 mov %r13,0x88(%r15)
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 7f 05 00 00 jne 0x5b3
34: 49 8d bf 90 00 00 00 lea 0x90(%r15),%rdi
3b: 48 8b 6d 08 mov 0x8(%rbp),%rbp
3f: 48 rex.W


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