[syzbot] [media?] KMSAN: uninit-value in vidtv_ts_null_write_into

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: cd7a5651db26 alpha: add missing address argument in call t..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=125b62aa580000
kernel config: https://syzkaller.appspot.com/x/.config?x=50148b563a4d5941
dashboard link: https://syzkaller.appspot.com/bug?extid=96f901260a0b2d29cd1a
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=13e5a6e6580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=172c7e5a580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/23c623fcb1bf/disk-cd7a5651.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5128bb44f38d/vmlinux-cd7a5651.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a65d6b263e08/bzImage-cd7a5651.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+96f901...@syzkaller.appspotmail.com

=====================================================
BUG: KMSAN: uninit-value in vidtv_ts_null_write_into+0x43e/0x5c0 drivers/media/test-drivers/vidtv/vidtv_ts.c:62
vidtv_ts_null_write_into+0x43e/0x5c0 drivers/media/test-drivers/vidtv/vidtv_ts.c:62
vidtv_mux_pad_with_nulls drivers/media/test-drivers/vidtv/vidtv_mux.c:366 [inline]
vidtv_mux_tick+0x34b7/0x3e40 drivers/media/test-drivers/vidtv/vidtv_mux.c:411
process_one_work kernel/workqueue.c:3275 [inline]
process_scheduled_works+0xae7/0x1d60 kernel/workqueue.c:3358
worker_thread+0xede/0x1580 kernel/workqueue.c:3439
kthread+0x53f/0x600 kernel/kthread.c:467
ret_from_fork+0x20f/0x910 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Uninit was stored to memory at:
vidtv_ts_null_write_into+0x437/0x5c0 drivers/media/test-drivers/vidtv/vidtv_ts.c:64
vidtv_mux_pad_with_nulls drivers/media/test-drivers/vidtv/vidtv_mux.c:366 [inline]
vidtv_mux_tick+0x34b7/0x3e40 drivers/media/test-drivers/vidtv/vidtv_mux.c:411
process_one_work kernel/workqueue.c:3275 [inline]
process_scheduled_works+0xae7/0x1d60 kernel/workqueue.c:3358
worker_thread+0xede/0x1580 kernel/workqueue.c:3439
kthread+0x53f/0x600 kernel/kthread.c:467
ret_from_fork+0x20f/0x910 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Local variable args.i134 created at:
vidtv_mux_pad_with_nulls drivers/media/test-drivers/vidtv/vidtv_mux.c:351 [inline]
vidtv_mux_tick+0x3150/0x3e40 drivers/media/test-drivers/vidtv/vidtv_mux.c:411
process_one_work kernel/workqueue.c:3275 [inline]
process_scheduled_works+0xae7/0x1d60 kernel/workqueue.c:3358

CPU: 1 UID: 0 PID: 30 Comm: kworker/1:1 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: events vidtv_mux_tick
=====================================================


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup