Re: [PATCH] media: vidtv: fix uninitialized args.buf_sz passed by value

[Ding Yihan]

Hi Thomas and Abd-Alrhman,

While looking into this exact same syzbot report, I noticed that 
`vidtv_ts_pcr_write_into()` in the same file also suffers from the
 exact same pass-by-value anti-pattern (passing `struct pcr_write_args` by value). 

Since `pcr_write_args` also contains implicit padding, it remains a potential trigger
 for identical KMSAN uninit-value warnings during fuzzing in the future.

Also, regarding Thomas's concern about modifying shared data: passing the struct 
as a `const pointer` (e.g., `const struct null_packet_write_args *`) 
would perfectly guarantee that the state remains read-only.

Thomas, would it be worth submitting a separate patch now to fix `vidtv_ts_pcr_write_into()`
to prevent future KMSAN errors? Or would you prefer this to be addressed together in Abd-Alrhman's v2?

Best regards,
Yihan Ding