Re: [PATCH 2/3] vfs: retire user_path_at_empty and drop empty arg from getname_flags

From: Jan Kara
Date: Wed Jun 05 2024 - 11:49:03 EST

On Tue 04-06-24 17:52:56, Mateusz Guzik wrote:
> No users after do_readlinkat started doing the job on its own.
>
> Signed-off-by: Mateusz Guzik <mjguzik@xxxxxxxxx>

Looks good to me. Feel free to add:

Reviewed-by: Jan Kara <jack@xxxxxxx>

Honza

> ---
> fs/fsopen.c | 2 +-
> fs/namei.c | 16 +++++++---------
> fs/stat.c | 6 +++---
> include/linux/fs.h | 2 +-
> include/linux/namei.h | 8 +-------
> io_uring/statx.c | 3 +--
> io_uring/xattr.c | 4 ++--
> 7 files changed, 16 insertions(+), 25 deletions(-)
>
> diff --git a/fs/fsopen.c b/fs/fsopen.c
> index 6593ae518115..e7d0080c4f8b 100644
> --- a/fs/fsopen.c
> +++ b/fs/fsopen.c
> @@ -451,7 +451,7 @@ SYSCALL_DEFINE5(fsconfig,
> fallthrough;
> case FSCONFIG_SET_PATH:
> param.type = fs_value_is_filename;
> - param.name = getname_flags(_value, lookup_flags, NULL);
> + param.name = getname_flags(_value, lookup_flags);
> if (IS_ERR(param.name)) {
> ret = PTR_ERR(param.name);
> goto out_key;
> diff --git a/fs/namei.c b/fs/namei.c
> index 37fb0a8aa09a..950ad6bdd9fe 100644
> --- a/fs/namei.c
> +++ b/fs/namei.c
> @@ -126,7 +126,7 @@
> #define EMBEDDED_NAME_MAX (PATH_MAX - offsetof(struct filename, iname))
>
> struct filename *
> -getname_flags(const char __user *filename, int flags, int *empty)
> +getname_flags(const char __user *filename, int flags)
> {
> struct filename *result;
> char *kname;
> @@ -190,8 +190,6 @@ getname_flags(const char __user *filename, int flags, int *empty)
> atomic_set(&result->refcnt, 1);
> /* The empty path is special. */
> if (unlikely(!len)) {
> - if (empty)
> - *empty = 1;
> if (!(flags & LOOKUP_EMPTY)) {
> putname(result);
> return ERR_PTR(-ENOENT);
> @@ -209,13 +207,13 @@ getname_uflags(const char __user *filename, int uflags)
> {
> int flags = (uflags & AT_EMPTY_PATH) ? LOOKUP_EMPTY : 0;
>
> - return getname_flags(filename, flags, NULL);
> + return getname_flags(filename, flags);
> }
>
> struct filename *
> getname(const char __user * filename)
> {
> - return getname_flags(filename, 0, NULL);
> + return getname_flags(filename, 0);
> }
>
> struct filename *
> @@ -2922,16 +2920,16 @@ int path_pts(struct path *path)
> }
> #endif
>
> -int user_path_at_empty(int dfd, const char __user *name, unsigned flags,
> - struct path *path, int *empty)
> +int user_path_at(int dfd, const char __user *name, unsigned flags,
> + struct path *path)
> {
> - struct filename *filename = getname_flags(name, flags, empty);
> + struct filename *filename = getname_flags(name, flags);
> int ret = filename_lookup(dfd, filename, flags, path, NULL);
>
> putname(filename);
> return ret;
> }
> -EXPORT_SYMBOL(user_path_at_empty);
> +EXPORT_SYMBOL(user_path_at);
>
> int __check_sticky(struct mnt_idmap *idmap, struct inode *dir,
> struct inode *inode)
> diff --git a/fs/stat.c b/fs/stat.c
> index 7f7861544500..16aa1f5ceec4 100644
> --- a/fs/stat.c
> +++ b/fs/stat.c
> @@ -300,7 +300,7 @@ int vfs_fstatat(int dfd, const char __user *filename,
> return vfs_fstat(dfd, stat);
> }
>
> - name = getname_flags(filename, getname_statx_lookup_flags(statx_flags), NULL);
> + name = getname_flags(filename, getname_statx_lookup_flags(statx_flags));
> ret = vfs_statx(dfd, name, statx_flags, stat, STATX_BASIC_STATS);
> putname(name);
>
> @@ -496,7 +496,7 @@ static int do_readlinkat(int dfd, const char __user *pathname,
> return -EINVAL;
>
> retry:
> - name = getname_flags(pathname, lookup_flags, NULL);
> + name = getname_flags(pathname, lookup_flags);
> error = filename_lookup(dfd, name, lookup_flags, &path, NULL);
> if (unlikely(error)) {
> putname(name);
> @@ -710,7 +710,7 @@ SYSCALL_DEFINE5(statx,
> int ret;
> struct filename *name;
>
> - name = getname_flags(filename, getname_statx_lookup_flags(flags), NULL);
> + name = getname_flags(filename, getname_statx_lookup_flags(flags));
> ret = do_statx(dfd, name, flags, mask, buffer);
> putname(name);
>
> diff --git a/include/linux/fs.h b/include/linux/fs.h
> index 0283cf366c2a..dfe22a622df6 100644
> --- a/include/linux/fs.h
> +++ b/include/linux/fs.h
> @@ -2685,7 +2685,7 @@ static inline struct file *file_clone_open(struct file *file)
> }
> extern int filp_close(struct file *, fl_owner_t id);
>
> -extern struct filename *getname_flags(const char __user *, int, int *);
> +extern struct filename *getname_flags(const char __user *, int);
> extern struct filename *getname_uflags(const char __user *, int);
> extern struct filename *getname(const char __user *);
> extern struct filename *getname_kernel(const char *);
> diff --git a/include/linux/namei.h b/include/linux/namei.h
> index 967aa9ea9f96..8ec8fed3bce8 100644
> --- a/include/linux/namei.h
> +++ b/include/linux/namei.h
> @@ -50,13 +50,7 @@ enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT};
>
> extern int path_pts(struct path *path);
>
> -extern int user_path_at_empty(int, const char __user *, unsigned, struct path *, int *empty);
> -
> -static inline int user_path_at(int dfd, const char __user *name, unsigned flags,
> - struct path *path)
> -{
> - return user_path_at_empty(dfd, name, flags, path, NULL);
> -}
> +extern int user_path_at(int, const char __user *, unsigned, struct path *);
>
> struct dentry *lookup_one_qstr_excl(const struct qstr *name,
> struct dentry *base,
> diff --git a/io_uring/statx.c b/io_uring/statx.c
> index abb874209caa..f7f9b202eec0 100644
> --- a/io_uring/statx.c
> +++ b/io_uring/statx.c
> @@ -37,8 +37,7 @@ int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
> sx->flags = READ_ONCE(sqe->statx_flags);
>
> sx->filename = getname_flags(path,
> - getname_statx_lookup_flags(sx->flags),
> - NULL);
> + getname_statx_lookup_flags(sx->flags));
>
> if (IS_ERR(sx->filename)) {
> int ret = PTR_ERR(sx->filename);
> diff --git a/io_uring/xattr.c b/io_uring/xattr.c
> index 44905b82eea8..6cf41c3bc369 100644
> --- a/io_uring/xattr.c
> +++ b/io_uring/xattr.c
> @@ -96,7 +96,7 @@ int io_getxattr_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
>
> path = u64_to_user_ptr(READ_ONCE(sqe->addr3));
>
> - ix->filename = getname_flags(path, LOOKUP_FOLLOW, NULL);
> + ix->filename = getname_flags(path, LOOKUP_FOLLOW);
> if (IS_ERR(ix->filename)) {
> ret = PTR_ERR(ix->filename);
> ix->filename = NULL;
> @@ -189,7 +189,7 @@ int io_setxattr_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
>
> path = u64_to_user_ptr(READ_ONCE(sqe->addr3));
>
> - ix->filename = getname_flags(path, LOOKUP_FOLLOW, NULL);
> + ix->filename = getname_flags(path, LOOKUP_FOLLOW);
> if (IS_ERR(ix->filename)) {
> ret = PTR_ERR(ix->filename);
> ix->filename = NULL;
> --
> 2.39.2
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR