Subject: Re: [PATCH iproute2-next v2] lib/fs: fix issue when {name,open}_to_handle_at() is not implemented

From: Petr Vorel <[email-masked]>
Date: Fri, 30 Apr 2021 21:07:05 +0200

Hi,

> +++ b/lib/fs.c
> @@ -30,6 +30,27 @@
>  /* if not already mounted cgroup2 is mounted here for iproute2's use */
>  #define MNT_CGRP2_PATH  "/var/run/cgroup2"

> +
> +#ifndef defined HAVE_HANDLE_AT
This is also wrong, it must be:
#ifndef HAVE_HANDLE_AT

> +struct file_handle {
> +	unsigned handle_bytes;
> +	int handle_type;
> +	unsigned char f_handle[];
> +};
> +
> +int name_to_handle_at(int dirfd, const char *pathname,
> +	struct file_handle *handle, int *mount_id, int flags)
> +{
> +	return syscall(name_to_handle_at, 5, dirfd, pathname, handle,
> +	               mount_id, flags);
Also I overlooked bogus 5 parameter, why is here? Correct is:

	return syscall(__NR_name_to_handle_at, dfd, pathname, handle,
			   mount_id, flags);
> +}
> +
> +int open_by_handle_at(int mount_fd, struct file_handle *handle, int flags)
> +{
> +	return syscall(open_by_handle_at, 3, mount_fd, handle, flags);
And here 3, correct version is is:
	return syscall(__NR_open_by_handle_at, mount_fd, handle, flags);

+ adding at the top:

#ifndef HAVE_HANDLE_AT
# include <sys/syscall.h>
#endif

Kind regards,
Petr