Re: [PATCH v5 4/4] ceph: Remove S_ISGID clear code in ceph_finish_async_create

[Xiubo Li <xiubli@redhat.com>]

On 4/21/22 3:54 PM, Yang Xu wrote:
> Since vfs has stripped S_ISGID in the previous patch, the calltrace
> as below:
>
> vfs:	lookup_open
> 	...
> 	  if (open_flag & O_CREAT) {
>                  if (open_flag & O_EXCL)
>                          open_flag &= ~O_TRUNC;
>                  mode = prepare_mode(mnt_userns, dir->d_inode, mode);
> 	...
> 	   dir_inode->i_op->atomic_open
>
> ceph:	ceph_atomic_open
> 	...
> 	      if (flags & O_CREAT)
>              		ceph_finish_async_create
>
> We have stripped sgid in prepare_mode, so remove this useless clear
> code directly.
>
> Signed-off-by: Yang Xu <xuyang2018.jy@fujitsu.com>
> ---
>   fs/ceph/file.c | 4 ----
>   1 file changed, 4 deletions(-)
>
> diff --git a/fs/ceph/file.c b/fs/ceph/file.c
> index 6c9e837aa1d3..8e3b99853333 100644
> --- a/fs/ceph/file.c
> +++ b/fs/ceph/file.c
> @@ -651,10 +651,6 @@ static int ceph_finish_async_create(struct inode *dir, struct dentry *dentry,
>   		/* Directories always inherit the setgid bit. */
>   		if (S_ISDIR(mode))
>   			mode |= S_ISGID;
> -		else if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP) &&
> -			 !in_group_p(dir->i_gid) &&
> -			 !capable_wrt_inode_uidgid(&init_user_ns, dir, CAP_FSETID))
> -			mode &= ~S_ISGID;
>   	} else {
>   		in.gid = cpu_to_le32(from_kgid(&init_user_ns, current_fsgid()));
>   	}

LGTM.

Reviewed-by: Xiubo Li <xiubli@redhat.com>