RE: [PATCH v1 1/1] seq_file: Replace strncpy()+nul by strscpy()

[David Laight]

From: Andy Shevchenko
> Sent: 17 July 2023 10:34
...
>  #define seq_show_option_n(m, name, value, length) {	\
>  	char val_buf[length + 1];			\
> -	strncpy(val_buf, value, length);		\
> -	val_buf[length] = '\0';				\
> +	strscpy(val_buf, value, sizeof(val_buf));	\
>  	seq_show_option(m, name, val_buf);		\
>  }

Why the extra double-copy with (potentially) a VLA?

seq_show_option() calls seq_escape_str(),
seq_escape_str calls seq_escape_mem(...  strlen(src) ...).

Implement seq_show_option() as seq_show_option_n(... strlen(value))
and use seq_escape_mem() for the value.

	David

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