Subject: Re: linux-next: manual merge of the pidfd tree with the overlayfs tree

From: Stephen Rothwell <[email-masked]>
Date: Fri, 5 Feb 2021 09:40:26 +1100

Hi all,

On Mon, 25 Jan 2021 17:07:16 +1100 Stephen Rothwell <[email-masked]> wrote:
>
> Today's linux-next merge of the pidfd tree got a conflict in:
> 
>   fs/overlayfs/inode.c
> 
> between commit:
> 
>   9c09be9e71c4 ("ovl: perform vfs_getxattr() with mounter creds")
> 
> from the overlayfs tree and commit:
> 
>   c7c7a1a18af4 ("xattr: handle idmapped mounts")
> 
> from the pidfd tree.
> 
> I fixed it up (see below) and can carry the fix as necessary. This
> is now fixed as far as linux-next is concerned, but any non trivial
> conflicts should be mentioned to your upstream maintainer when your tree
> is submitted for merging.  You may also want to consider cooperating
> with the maintainer of the conflicting tree to minimise any particularly
> complex conflicts.
> 
> 
> diff --cc fs/overlayfs/inode.c
> index cf41bcb664bc,e78d45dfeaee..000000000000
> --- a/fs/overlayfs/inode.c
> +++ b/fs/overlayfs/inode.c
> @@@ -352,9 -354,7 +354,9 @@@ int ovl_xattr_set(struct dentry *dentry
>   		goto out;
>   
>   	if (!value && !upperdentry) {
>  +		old_cred = ovl_override_creds(dentry->d_sb);
> - 		err = vfs_getxattr(realdentry, name, NULL, 0);
> + 		err = vfs_getxattr(&init_user_ns, realdentry, name, NULL, 0);
>  +		revert_creds(old_cred);
>   		if (err < 0)
>   			goto out_drop_write;
>   	}

This is now a conflict between the pidfd tree and Linus' tree.

-- 
Cheers,
Stephen Rothwell