On Mon, Feb 10, 2025 at 1:39 PM Christian Brauner <brauner@xxxxxxxxxx> wrote:
>
> Let FSCONFIG_SET_FD handle O_PATH file descriptors. This is particularly
> useful in the context of overlayfs where layers can be specified via
> file descriptors instead of paths. But userspace must currently use
> non-O_PATH file desriptors which is often pointless especially if
> the file descriptors have been created via open_tree(OPEN_TREE_CLONE).
>
> Fixes: a08557d19ef41 ("ovl: specify layers via file descriptors")
> Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx>
> ---
> fs/autofs/autofs_i.h | 2 ++
> fs/fsopen.c | 2 +-
> 2 files changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/fs/autofs/autofs_i.h b/fs/autofs/autofs_i.h
> index 77c7991d89aa..23cea74f9933 100644
> --- a/fs/autofs/autofs_i.h
> +++ b/fs/autofs/autofs_i.h
> @@ -218,6 +218,8 @@ void autofs_clean_ino(struct autofs_info *);
>
> static inline int autofs_check_pipe(struct file *pipe)
> {
> + if (pipe->f_mode & FMODE_PATH)
> + return -EINVAL;
> if (!(pipe->f_mode & FMODE_CAN_WRITE))
> return -EINVAL;
I thought you said the above check is redundant due to the lower check.
In any case feel free to add
Reviewed-by: Amir Goldstein <amir73il@xxxxxxxxx>
> if (!S_ISFIFO(file_inode(pipe)->i_mode))
> diff --git a/fs/fsopen.c b/fs/fsopen.c
> index 094a7f510edf..1aaf4cb2afb2 100644
> --- a/fs/fsopen.c
> +++ b/fs/fsopen.c
> @@ -453,7 +453,7 @@ SYSCALL_DEFINE5(fsconfig,
> case FSCONFIG_SET_FD:
> param.type = fs_value_is_file;
> ret = -EBADF;
> - param.file = fget(aux);
> + param.file = fget_raw(aux);
> if (!param.file)
> goto out_key;
> param.dirfd = aux;
>
> --
> 2.47.2
>
