From: Christian Brauner <brauner@kernel.org>
Date: Mon, 4 Apr 2022 10:51:58 +0000 (+0200)
Subject: ovl: support idmapped layers
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=bc70682a497c4f3c968c552e465d1d9948b1ff4c;p=linux.git

ovl: support idmapped layers

Now that overlay is able to take a layers idmapping into account allow
overlay mounts to be created on top of idmapped mounts.

Cc: <linux-unionfs@vger.kernel.org>
Tested-by: Giuseppe Scrivano <gscrivan@redhat.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
---

diff --git a/fs/overlayfs/ovl_entry.h b/fs/overlayfs/ovl_entry.h
index 469162ca9b213..e1af8f6606984 100644
--- a/fs/overlayfs/ovl_entry.h
+++ b/fs/overlayfs/ovl_entry.h
@@ -92,7 +92,7 @@ static inline struct vfsmount *ovl_upper_mnt(struct ovl_fs *ofs)
 
 static inline struct user_namespace *ovl_upper_mnt_userns(struct ovl_fs *ofs)
 {
-	return &init_user_ns;
+	return mnt_user_ns(ovl_upper_mnt(ofs));
 }
 
 static inline struct ovl_fs *OVL_FS(struct super_block *sb)
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 0123c8086ee96..e0a2e0468ee7f 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -874,10 +874,6 @@ static int ovl_mount_dir_noesc(const char *name, struct path *path)
 		pr_err("filesystem on '%s' not supported\n", name);
 		goto out_put;
 	}
-	if (is_idmapped_mnt(path->mnt)) {
-		pr_err("idmapped layers are currently not supported\n");
-		goto out_put;
-	}
 	if (!d_is_dir(path->dentry)) {
 		pr_err("'%s' not a directory\n", name);
 		goto out_put;