APPLIED/cmnt: [PATCH][SRU][Disco] UBUNTU: SAUCE: shiftfs: use separate llseek method for directories

[Kleber Souza]

On 4/16/19 6:29 PM, Christian Brauner wrote:
> BugLink: https://bugs.launchpad.net/bugs/1824812
> 
> Give shiftfs it's own proper llseek method for directories.
> 
> Before this commit we used to rely on an llseek method that was targeted
> for regular files for both directories and regular files. Give
> directories their own llseek operation.
> This is required to have AppArmor function correctly with shiftfs.
> 
> Signed-off-by: Christian Brauner <christian.brauner at ubuntu.com>

Applied to disco/master-next branch, changing the commit message to the
one suggested by Tyler.

Thanks,
Kleber

> ---
>  fs/shiftfs.c | 14 +++++++++++---
>  1 file changed, 11 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/shiftfs.c b/fs/shiftfs.c
> index 4c8a6ec2a617..9771165d1ce0 100644
> --- a/fs/shiftfs.c
> +++ b/fs/shiftfs.c
> @@ -1144,7 +1144,15 @@ static int shiftfs_release(struct inode *inode, struct file *file)
>  	return 0;
>  }
>  
> -static loff_t shiftfs_llseek(struct file *file, loff_t offset, int whence)
> +static loff_t shiftfs_dir_llseek(struct file *file, loff_t offset, int whence)
> +{
> +	struct shiftfs_file_info *file_info = file->private_data;
> +	struct file *realfile = file_info->realfile;
> +
> +	return vfs_llseek(realfile, offset, whence);
> +}
> +
> +static loff_t shiftfs_file_llseek(struct file *file, loff_t offset, int whence)
>  {
>  	struct inode *realinode = file_inode(file)->i_private;
>  
> @@ -1653,7 +1661,7 @@ static int shiftfs_iterate_shared(struct file *file, struct dir_context *ctx)
>  const struct file_operations shiftfs_file_operations = {
>  	.open			= shiftfs_open,
>  	.release		= shiftfs_release,
> -	.llseek			= shiftfs_llseek,
> +	.llseek			= shiftfs_file_llseek,
>  	.read_iter		= shiftfs_read_iter,
>  	.write_iter		= shiftfs_write_iter,
>  	.fsync			= shiftfs_fsync,
> @@ -1670,7 +1678,7 @@ const struct file_operations shiftfs_dir_operations = {
>  	.compat_ioctl		= shiftfs_compat_ioctl,
>  	.fsync			= shiftfs_fsync,
>  	.iterate_shared		= shiftfs_iterate_shared,
> -	.llseek			= shiftfs_llseek,
> +	.llseek			= shiftfs_dir_llseek,
>  	.open			= shiftfs_open,
>  	.read			= generic_read_dir,
>  	.release		= shiftfs_release,
>