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

From: Stephen Rothwell <[email-masked]>
Date: Fri, 5 Feb 2021 09:42:05 +1100

Hi all,

On Mon, 25 Jan 2021 17:04:26 +1100 Stephen Rothwell <[email-masked]> wrote:
>
> Today's linux-next merge of the pidfd tree got a conflict in:
> 
>   fs/overlayfs/copy_up.c
> 
> between commit:
> 
>   06896fa3193d ("ovl: skip getxattr of security labels")
> 
> 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/copy_up.c
> index 0fed532efa68,f81b836c2256..000000000000
> --- a/fs/overlayfs/copy_up.c
> +++ b/fs/overlayfs/copy_up.c
> @@@ -84,18 -84,10 +84,18 @@@ int ovl_copy_xattr(struct super_block *
>   
>   		if (ovl_is_private_xattr(sb, name))
>   			continue;
>  +
>  +		error = security_inode_copy_up_xattr(name);
>  +		if (error < 0 && error != -EOPNOTSUPP)
>  +			break;
>  +		if (error == 1) {
>  +			error = 0;
>  +			continue; /* Discard */
>  +		}
>   retry:
> - 		size = vfs_getxattr(old, name, value, value_size);
> + 		size = vfs_getxattr(&init_user_ns, old, name, value, value_size);
>   		if (size == -ERANGE)
> - 			size = vfs_getxattr(old, name, NULL, 0);
> + 			size = vfs_getxattr(&init_user_ns, old, name, NULL, 0);
>   
>   		if (size < 0) {
>   			error = size;
> @@@ -115,7 -107,14 +115,7 @@@
>   			goto retry;
>   		}
>   
> - 		error = vfs_setxattr(new, name, value, size, 0);
>  -		error = security_inode_copy_up_xattr(name);
>  -		if (error < 0 && error != -EOPNOTSUPP)
>  -			break;
>  -		if (error == 1) {
>  -			error = 0;
>  -			continue; /* Discard */
>  -		}
> + 		error = vfs_setxattr(&init_user_ns, new, name, value, size, 0);
>   		if (error) {
>   			if (error != -EOPNOTSUPP || ovl_must_copy_xattr(name))
>   				break;

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

-- 
Cheers,
Stephen Rothwell