On Wed, Aug 17, 2022 at 6:49 AM Zhang Tianci
<zhangtianci.1997@xxxxxxxxxxxxx> wrote:
>
> ovl_link() did not create a new inode after commit
> 51f7e52dc943 ("ovl: share inode for hard link"), so
> in ovl_create_or_link() we should not override cred's
> fsuid and fsgid when called by ovl_link().
>
> Signed-off-by: Zhang Tianci <zhangtianci.1997@xxxxxxxxxxxxx>
> Signed-off-by: Jiachen Zhang <zhangjiachen.jaycee@xxxxxxxxxxxxx>
> ---
> fs/overlayfs/dir.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
> index 6b03457f72bb..568d338032db 100644
> --- a/fs/overlayfs/dir.c
> +++ b/fs/overlayfs/dir.c
> @@ -595,9 +595,9 @@ static int ovl_create_or_link(struct dentry *dentry, struct inode *inode,
> err = -ENOMEM;
> override_cred = prepare_creds();
> if (override_cred) {
> - override_cred->fsuid = inode->i_uid;
> - override_cred->fsgid = inode->i_gid;
> if (!attr->hardlink) {
> + override_cred->fsuid = inode->i_uid;
> + override_cred->fsgid = inode->i_gid;
> err = security_dentry_create_files_as(dentry,
> attr->mode, &dentry->d_name, old_cred,
> override_cred);
> --
This change looks incorrect.
Unless I am missing something, fsuid/fsgid still need to
be overridden for calling link() on underlying fs.
What made you do this change?
Thanks,
Amir.
