On Sat, May 22, 2021 at 07:31:53PM +0800, menglong8.dong@xxxxxxxxx wrote:
> Introduce the function ramdisk_exec_exist, which is used to check
> the exist of 'ramdisk_execute_command'.
>
> It can do absolute path and relative path check. For relative path,
> it will ignore '/' and '.' in the start of
> 'ramdisk_execute_command'.
> --- a/init/main.c
> +++ b/init/main.c
> @@ -1522,6 +1522,21 @@ void __init console_on_rootfs(void)
> fput(file);
> }
>
> +bool __init ramdisk_exec_exist(bool absolute)
> +{
> + char *tmp_command = ramdisk_execute_command;
> +
> + if (!tmp_command)
> + return false;
> +
> + if (!absolute) {
> + while (*tmp_command == '/' || *tmp_command == '.')
> + tmp_command++;
As far as I can tell, this will break if the user wants to use
".mybinary" or ".mydir/mybinary" as the name of their init program.
For that matter, it would break "...prog" or "...somedir/prog", which
would be strange but not something the kernel should prevent.
I don't think this code should be attempting to recreate
relative-to-absolute filename resolution.
