[syzbot] [serial?] general protection fault in fn_enter

syzbot
2026-01-28T00:35:34Z

Hello,

syzbot found the following issue on:

HEAD commit: 615aad0f61e0 Add linux-next specific files for 20260126
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=1625a6ef980000
kernel config: https://syzkaller.appspot.com/x/.config?x=d51c584a7396ddf1
dashboard link: https://syzkaller.appspot.com/bug?extid=bbe4d8bcf8e458140bb8
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11747d2a580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1190d05a580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5318e5f027be/disk-615aad0f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/d165e561fa49/vmlinux-615aad0f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/fb0e01c90aa5/bzImage-615aad0f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+bbe4d8bcf8e458140bb8@syzkaller.appspotmail.com

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000038: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x00000000000001c0-0x00000000000001c7]
CPU: 1 UID: 0 PID: 6023 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026
RIP: 0010:__queue_work+0xa2/0xf90 kernel/workqueue.c:2269
Code: 11 31 ff 89 ee e8 4e f4 37 00 85 ed 0f 85 ef 0c 00 00 e8 01 f0 37 00 4d 8d b7 c0 01 00 00 4c 89 f0 48 c1 e8 03 48 89 44 24 28 <42> 0f b6 04 20 84 c0 0f 85 22 0d 00 00 4c 89 34 24 41 8b 2e 89 ee
RSP: 0018:ffffc900036f74b8 EFLAGS: 00010002
RAX: 0000000000000038 RBX: 0000000000000008 RCX: ffff888031643c80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffff88813ff72017 R09: 1ffff11027fee402
R10: dffffc0000000000 R11: ffffed1027fee403 R12: dffffc0000000000
R13: ffff88813ff72010 R14: 00000000000001c0 R15: 0000000000000000
FS: 0000555577a96500(0000) GS:ffff8881253b4000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fccc4f840c0 CR3: 000000007b780000 CR4: 00000000003526f0
Call Trace:
<TASK>
queue_work_on+0x106/0x1d0 kernel/workqueue.c:2405
put_queue drivers/tty/vt/keyboard.c:328 [inline]
fn_enter+0x45d/0x900 drivers/tty/vt/keyboard.c:480
kbd_keycode drivers/tty/vt/keyboard.c:1497 [inline]
kbd_event+0x2ec1/0x40d0 drivers/tty/vt/keyboard.c:1515
input_handle_events_default+0xd4/0x1a0 drivers/input/input.c:2541
input_pass_values+0x288/0x890 drivers/input/input.c:128
input_event_dispose+0x330/0x6b0 drivers/input/input.c:342
input_inject_event+0x1dd/0x340 drivers/input/input.c:424
evdev_write+0x325/0x4c0 drivers/input/evdev.c:528
vfs_write+0x29a/0xb90 fs/read_write.c:686
ksys_write+0x150/0x270 fs/read_write.c:740
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fccc4f9aeb9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe15585178 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fccc5215fa0 RCX: 00007fccc4f9aeb9
RDX: 00000000000012d8 RSI: 0000200000000040 RDI: 0000000000000003
RBP: 00007fccc5008c1f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fccc5215fac R14: 00007fccc5215fa0 R15: 00007fccc5215fa0
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__queue_work+0xa2/0xf90 kernel/workqueue.c:2269
Code: 11 31 ff 89 ee e8 4e f4 37 00 85 ed 0f 85 ef 0c 00 00 e8 01 f0 37 00 4d 8d b7 c0 01 00 00 4c 89 f0 48 c1 e8 03 48 89 44 24 28 <42> 0f b6 04 20 84 c0 0f 85 22 0d 00 00 4c 89 34 24 41 8b 2e 89 ee
RSP: 0018:ffffc900036f74b8 EFLAGS: 00010002
RAX: 0000000000000038 RBX: 0000000000000008 RCX: ffff888031643c80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffff88813ff72017 R09: 1ffff11027fee402
R10: dffffc0000000000 R11: ffffed1027fee403 R12: dffffc0000000000
R13: ffff88813ff72010 R14: 00000000000001c0 R15: 0000000000000000
FS: 0000555577a96500(0000) GS:ffff8881253b4000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fccc4f840c0 CR3: 000000007b780000 CR4: 00000000003526f0
----------------
Code disassembly (best guess), 1 bytes skipped:
0: 31 ff xor %edi,%edi
2: 89 ee mov %ebp,%esi
4: e8 4e f4 37 00 call 0x37f457
9: 85 ed test %ebp,%ebp
b: 0f 85 ef 0c 00 00 jne 0xd00
11: e8 01 f0 37 00 call 0x37f017
16: 4d 8d b7 c0 01 00 00 lea 0x1c0(%r15),%r14
1d: 4c 89 f0 mov %r14,%rax
20: 48 c1 e8 03 shr $0x3,%rax
24: 48 89 44 24 28 mov %rax,0x28(%rsp)
* 29: 42 0f b6 04 20 movzbl (%rax,%r12,1),%eax <-- trapping instruction
2e: 84 c0 test %al,%al
30: 0f 85 22 0d 00 00 jne 0xd58
36: 4c 89 34 24 mov %r14,(%rsp)
3a: 41 8b 2e mov (%r14),%ebp
3d: 89 ee mov %ebp,%esi

---
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