Re: [PATCH RFC v2 3/3] pidfs: support FS_IOC_GETVERSION

Jan Kara
2024-12-02T15:35:50Z

On Fri 29-11-24 14:02:25, Christian Brauner wrote:
> This will allow 32 bit userspace to detect when a given inode number has
> been recycled and also to construct a unique 64 bit identifier.
>
> Signed-off-by: Christian Brauner <brauner@kernel.org>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <jack@suse.cz>

Honza

> ---
> fs/pidfs.c | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> diff --git a/fs/pidfs.c b/fs/pidfs.c
> index ff4f25078f3d983bce630e597adbb12262e5d727..f73a47e1d8379df886a90a044fb887f8d06f7c0b 100644
> --- a/fs/pidfs.c
> +++ b/fs/pidfs.c
> @@ -262,6 +262,15 @@ static long pidfd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
> if (arg)
> return -EINVAL;
>
> + switch (cmd) {
> + case FS_IOC32_GETVERSION:
> + fallthrough;
> + case FS_IOC_GETVERSION: {
> + __u32 __user *argp = (__u32 __user *)arg;
> + return put_user(file_inode(file)->i_generation, argp);
> + }
> + }
> +
> scoped_guard(task_lock, task) {
> nsp = task->nsproxy;
> if (nsp)
>
> --
> 2.45.2
>
--
Jan Kara <jack@suse.com>
SUSE Labs, CR