Re: [PATCH RFC 4/6] fhandle: pull CAP_DAC_READ_SEARCH check into may_decode_fh()

Jan Kara
2024-12-02T16:01:02Z

On Fri 29-11-24 14:38:03, Christian Brauner wrote:
> There's no point in keeping it outside of that helper. This way we have
> all the permission pieces in one place.
>
> Signed-off-by: Christian Brauner <brauner@kernel.org>

Nice. Feel free to add:

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

Honza

> ---
> fs/fhandle.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/fs/fhandle.c b/fs/fhandle.c
> index c00d88fb14e16654b5cbbb71760c0478eac20384..031ad5592a0beabcc299436f037ad5fe626332e6 100644
> --- a/fs/fhandle.c
> +++ b/fs/fhandle.c
> @@ -298,6 +298,9 @@ static inline bool may_decode_fh(struct handle_to_path_ctx *ctx,
> {
> struct path *root = &ctx->root;
>
> + if (capable(CAP_DAC_READ_SEARCH))
> + return true;
> +
> /*
> * Restrict to O_DIRECTORY to provide a deterministic API that avoids a
> * confusing api in the face of disconnected non-dir dentries.
> @@ -337,7 +340,7 @@ static int handle_to_path(int mountdirfd, struct file_handle __user *ufh,
> if (retval)
> goto out_err;
>
> - if (!capable(CAP_DAC_READ_SEARCH) && !may_decode_fh(&ctx, o_flags)) {
> + if (!may_decode_fh(&ctx, o_flags)) {
> retval = -EPERM;
> goto out_path;
> }
>
> --
> 2.45.2
>
--
Jan Kara <jack@suse.com>
SUSE Labs, CR