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

[syzbot <syzbot+96f901260a0b2d29cd1a@syzkaller.appspotmail.com>]

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+96f901260a0b2d29cd1a@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
=====================================================


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