Re: [PATCH] fs/xattr: unify *at syscalls

[Jan Kara]

On Tue 30-04-24 17:19:14, Christian Göttsche wrote:
> From: Christian Göttsche <cgzones@xxxxxxxxxxxxxx>
> 
> Use the same parameter ordering for all four newly added *xattrat
> syscalls:
> 
>     dirfd, pathname, at_flags, ...
> 
> Also consistently use unsigned int as the type for at_flags.
> 
> Suggested-by: Jan Kara <jack@xxxxxxxx>
> Signed-off-by: Christian Göttsche <cgzones@xxxxxxxxxxxxxx>

Thanks! The change looks good to me. Christian, do you plan to fold this
into the series you've taken to your tree?

								Honza

> ---
>  fs/xattr.c               | 36 +++++++++++++++++++-----------------
>  include/linux/syscalls.h |  8 +++++---
>  2 files changed, 24 insertions(+), 20 deletions(-)
> 
> diff --git a/fs/xattr.c b/fs/xattr.c
> index 45603e74c632..454304046d7d 100644
> --- a/fs/xattr.c
> +++ b/fs/xattr.c
> @@ -931,17 +931,18 @@ listxattr(struct dentry *d, char __user *list, size_t size)
>  	return error;
>  }
>  
> -static ssize_t do_listxattrat(int dfd, const char __user *pathname, char __user *list,
> -			      size_t size, int flags)
> +static ssize_t do_listxattrat(int dfd, const char __user *pathname,
> +			      unsigned int at_flags,
> +			      char __user *list, size_t size)
>  {
>  	struct path path;
>  	ssize_t error = 0;
>  	int lookup_flags;
>  
> -	if ((flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0)
> +	if ((at_flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0)
>  		return -EINVAL;
>  
> -	if (flags & AT_EMPTY_PATH && vfs_empty_path(dfd, pathname)) {
> +	if (at_flags & AT_EMPTY_PATH && vfs_empty_path(dfd, pathname)) {
>  		CLASS(fd, f)(dfd);
>  
>  		if (!f.file)
> @@ -965,22 +966,23 @@ static ssize_t do_listxattrat(int dfd, const char __user *pathname, char __user
>  	return error;
>  }
>  
> -SYSCALL_DEFINE5(listxattrat, int, dfd, const char __user *, pathname, char __user *, list,
> -		size_t, size, int, flags)
> +SYSCALL_DEFINE5(listxattrat, int, dfd, const char __user *, pathname,
> +		unsigned int, at_flags,
> +		char __user *, list, size_t, size)
>  {
> -	return do_listxattrat(dfd, pathname, list, size, flags);
> +	return do_listxattrat(dfd, pathname, at_flags, list, size);
>  }
>  
>  SYSCALL_DEFINE3(listxattr, const char __user *, pathname, char __user *, list,
>  		size_t, size)
>  {
> -	return do_listxattrat(AT_FDCWD, pathname, list, size, 0);
> +	return do_listxattrat(AT_FDCWD, pathname, 0, list, size);
>  }
>  
>  SYSCALL_DEFINE3(llistxattr, const char __user *, pathname, char __user *, list,
>  		size_t, size)
>  {
> -	return do_listxattrat(AT_FDCWD, pathname, list, size, AT_SYMLINK_NOFOLLOW);
> +	return do_listxattrat(AT_FDCWD, pathname, AT_SYMLINK_NOFOLLOW, list, size);
>  }
>  
>  SYSCALL_DEFINE3(flistxattr, int, fd, char __user *, list, size_t, size)
> @@ -1019,17 +1021,17 @@ removexattr(struct mnt_idmap *idmap, struct dentry *d,
>  }
>  
>  static int do_removexattrat(int dfd, const char __user *pathname,
> -			    const char __user *name, int flags)
> +			    unsigned int at_flags, const char __user *name)
>  {
>  	struct path path;
>  	int error;
>  	int lookup_flags;
>  
> -	if ((flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0)
> +	if ((at_flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0)
>  		return -EINVAL;
>  
> -	lookup_flags = (flags & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW;
> -	if (flags & AT_EMPTY_PATH)
> +	lookup_flags = (at_flags & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW;
> +	if (at_flags & AT_EMPTY_PATH)
>  		lookup_flags |= LOOKUP_EMPTY;
>  retry:
>  	error = user_path_at(dfd, pathname, lookup_flags, &path);
> @@ -1049,21 +1051,21 @@ static int do_removexattrat(int dfd, const char __user *pathname,
>  }
>  
>  SYSCALL_DEFINE4(removexattrat, int, dfd, const char __user *, pathname,
> -		const char __user *, name, int, flags)
> +		unsigned int, at_flags, const char __user *, name)
>  {
> -	return do_removexattrat(dfd, pathname, name, flags);
> +	return do_removexattrat(dfd, pathname, at_flags, name);
>  }
>  
>  SYSCALL_DEFINE2(removexattr, const char __user *, pathname,
>  		const char __user *, name)
>  {
> -	return do_removexattrat(AT_FDCWD, pathname, name, 0);
> +	return do_removexattrat(AT_FDCWD, pathname, 0, name);
>  }
>  
>  SYSCALL_DEFINE2(lremovexattr, const char __user *, pathname,
>  		const char __user *, name)
>  {
> -	return do_removexattrat(AT_FDCWD, pathname, name, AT_SYMLINK_NOFOLLOW);
> +	return do_removexattrat(AT_FDCWD, pathname, AT_SYMLINK_NOFOLLOW, name);
>  }
>  
>  SYSCALL_DEFINE2(fremovexattr, int, fd, const char __user *, name)
> diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
> index e06fffc48535..ca3cba698602 100644
> --- a/include/linux/syscalls.h
> +++ b/include/linux/syscalls.h
> @@ -356,15 +356,17 @@ asmlinkage long sys_fgetxattr(int fd, const char __user *name,
>  			      void __user *value, size_t size);
>  asmlinkage long sys_listxattr(const char __user *path, char __user *list,
>  			      size_t size);
> -asmlinkage long sys_listxattrat(int dfd, const char __user *path, char __user *list,
> -			      size_t size, int flags);
> +asmlinkage long sys_listxattrat(int dfd, const char __user *path,
> +				unsigned int at_flags,
> +				char __user *list, size_t size);
>  asmlinkage long sys_llistxattr(const char __user *path, char __user *list,
>  			       size_t size);
>  asmlinkage long sys_flistxattr(int fd, char __user *list, size_t size);
>  asmlinkage long sys_removexattr(const char __user *path,
>  				const char __user *name);
>  asmlinkage long sys_removexattrat(int dfd, const char __user *path,
> -				const char __user *name, int flags);
> +				  unsigned int at_flags,
> +				  const char __user *name);
>  asmlinkage long sys_lremovexattr(const char __user *path,
>  				 const char __user *name);
>  asmlinkage long sys_fremovexattr(int fd, const char __user *name);
> -- 
> 2.43.0
> 
-- 
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR