Unverified Commit 899bf2ce authored by Christian Brauner's avatar Christian Brauner
Browse files

nfs: do not export idmapped mounts 

Prevent nfs from exporting idmapped mounts until we have ported it to
support exporting idmapped mounts.

Link: https://lore.kernel.org/linux-api/20210123130958.3t6kvgkl634njpsm@wittgenstein


Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: "J. Bruce Fields" <bfields@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: default avatarChristian Brauner <christian.brauner@ubuntu.com>
parent 029a52ad

fs/nfsd/export.c

+9 −3
Original line number Diff line number Diff line
@@ -369,8 +369,9 @@ static struct svc_export *svc_export_update(struct svc_export *new, 
					    struct svc_export *old);

static struct svc_export *svc_export_lookup(struct svc_export *);



static int check_export(struct inode *inode, int *flags, unsigned char *uuid)

static int check_export(struct path *path, int *flags, unsigned char *uuid)

{

	struct inode *inode = d_inode(path->dentry);



	/*

	 * We currently export only dirs, regular files, and (for v4
@@ -394,6 +395,7 @@ static int check_export(struct inode *inode, int *flags, unsigned char *uuid) 
	 *       or an FSID number (so NFSEXP_FSID or ->uuid is needed).

	 * 2:  We must be able to find an inode from a filehandle.

	 *       This means that s_export_op must be set.

	 * 3: We must not currently be on an idmapped mount.

	 */

	if (!(inode->i_sb->s_type->fs_flags & FS_REQUIRES_DEV) &&

	    !(*flags & NFSEXP_FSID) &&
@@ -408,6 +410,11 @@ static int check_export(struct inode *inode, int *flags, unsigned char *uuid) 
		return -EINVAL;

	}



	if (mnt_user_ns(path->mnt) != &init_user_ns) {

		dprintk("exp_export: export of idmapped mounts not yet supported.\n");

		return -EINVAL;

	}



	if (inode->i_sb->s_export_op->flags & EXPORT_OP_NOSUBTREECHK &&

	    !(*flags & NFSEXP_NOSUBTREECHECK)) {

		dprintk("%s: %s does not support subtree checking!\n",
@@ -636,8 +643,7 @@ static int svc_export_parse(struct cache_detail *cd, char *mesg, int mlen) 
				goto out4;

		}



		err = check_export(d_inode(exp.ex_path.dentry), &exp.ex_flags,

				   exp.ex_uuid);

		err = check_export(&exp.ex_path, &exp.ex_flags, exp.ex_uuid);

		if (err)

			goto out4;

		/*