Re: [RFC][PATCH 09/13] do_readlinkat(): import pathname only once

Jan Kara
2025-11-13T10:20:31Z

On Sun 09-11-25 06:37:41, Al Viro wrote:
> Take getname_flags() and putname() outside of retry loop.
>
> Since getname_flags() is the only thing that cares about LOOKUP_EMPTY,
> don't bother with setting LOOKUP_EMPTY in lookup_flags - just pass it
> to getname_flags() and be done with that.
>
> The things could be further simplified by use of cleanup.h stuff, but
> let's not clutter the patch with that.
>
> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Looks good. Feel free to add:

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

Honza

> ---
> fs/stat.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/fs/stat.c b/fs/stat.c
> index 6c79661e1b96..ee9ae2c3273a 100644
> --- a/fs/stat.c
> +++ b/fs/stat.c
> @@ -566,13 +566,13 @@ static int do_readlinkat(int dfd, const char __user *pathname,
> struct path path;
> struct filename *name;
> int error;
> - unsigned int lookup_flags = LOOKUP_EMPTY;
> + unsigned int lookup_flags = 0;
>
> if (bufsiz <= 0)
> return -EINVAL;
>
> + name = getname_flags(pathname, LOOKUP_EMPTY);
> retry:
> - name = getname_flags(pathname, lookup_flags);
> error = filename_lookup(dfd, name, lookup_flags, &path, NULL);
> if (unlikely(error)) {
> putname(name);
> @@ -593,11 +593,11 @@ static int do_readlinkat(int dfd, const char __user *pathname,
> error = (name->name[0] == '\0') ? -ENOENT : -EINVAL;
> }
> path_put(&path);
> - putname(name);
> if (retry_estale(error, lookup_flags)) {
> lookup_flags |= LOOKUP_REVAL;
> goto retry;
> }
> + putname(name);
> return error;
> }
>
> --
> 2.47.3
>
--
Jan Kara <jack@suse.com>
SUSE Labs, CR