6939941 problem with moving files in zfs

usr/src/uts/common/fs/zfs/sys/zfs_ctldir.h

@@ -19,8 +19,7 @@
  * CDDL HEADER END
  */
 /*
- * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
- * Use is subject to license terms.
+ * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  */
 
 #ifndef	_ZFS_CTLDIR_H
@@ -49,6 +48,7 @@ void zfsctl_destroy(zfsvfs_t *);
 vnode_t *zfsctl_root(znode_t *);
 void zfsctl_init(void);
 void zfsctl_fini(void);
+boolean_t zfsctl_is_node(vnode_t *);
 
 int zfsctl_rename_snapshot(const char *from, const char *to);
 int zfsctl_destroy_snapshot(const char *snapname, int force);

usr/src/uts/common/fs/zfs/zfs_ctldir.c

@@ -19,8 +19,7 @@
  * CDDL HEADER END
  */
 /*
- * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
- * Use is subject to license terms.
+ * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  */
 
 /*
@@ -186,6 +185,17 @@ zfsctl_fini(void)
 	zfsctl_ops_shares_dir = NULL;
 }
 
+boolean_t
+zfsctl_is_node(vnode_t *vp)
+{
+	return (vn_matchops(vp, zfsctl_ops_root) ||
+	    vn_matchops(vp, zfsctl_ops_snapdir) ||
+	    vn_matchops(vp, zfsctl_ops_snapshot) ||
+	    vn_matchops(vp, zfsctl_ops_shares) ||
+	    vn_matchops(vp, zfsctl_ops_shares_dir));
+
+}
+
 /*
  * Return the inode number associated with the 'snapshot' or
  * 'shares' directory.

usr/src/uts/common/fs/zfs/zfs_vnops.c

@@ -19,8 +19,7 @@
  * CDDL HEADER END
  */
 /*
- * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
- * Use is subject to license terms.
+ * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  */
 
 /* Portions Copyright 2007 Jeremy Teo */
@@ -3248,7 +3247,7 @@ zfs_rename(vnode_t *sdvp, char *snm, vnode_t *tdvp, char *tnm, cred_t *cr,
 	if (VOP_REALVP(tdvp, &realvp, ct) == 0)
 		tdvp = realvp;
 
-	if (tdvp->v_vfsp != sdvp->v_vfsp) {
+	if (tdvp->v_vfsp != sdvp->v_vfsp || zfsctl_is_node(tdvp)) {
 		ZFS_EXIT(zfsvfs);
 		return (EXDEV);
 	}
@@ -3747,6 +3746,7 @@ zfs_link(vnode_t *tdvp, vnode_t *svp, char *name, cred_t *cr,
 	vnode_t		*realvp;
 	int		error;
 	int		zf = ZNEW;
+	uint64_t	parent;
 
 	ASSERT(tdvp->v_type == VDIR);
 
@@ -3757,13 +3757,35 @@ zfs_link(vnode_t *tdvp, vnode_t *svp, char *name, cred_t *cr,
 	if (VOP_REALVP(svp, &realvp, ct) == 0)
 		svp = realvp;
 
-	if (svp->v_vfsp != tdvp->v_vfsp) {
+	/*
+	 * POSIX dictates that we return EPERM here.
+	 * Better choices include ENOTSUP or EISDIR.
+	 */
+	if (svp->v_type == VDIR) {
+		ZFS_EXIT(zfsvfs);
+		return (EPERM);
+	}
+
+	if (svp->v_vfsp != tdvp->v_vfsp || zfsctl_is_node(svp)) {
 		ZFS_EXIT(zfsvfs);
 		return (EXDEV);
 	}
+
 	szp = VTOZ(svp);
 	ZFS_VERIFY_ZP(szp);
 
+	/* Prevent links to .zfs/shares files */
+
+	if ((error = sa_lookup(szp->z_sa_hdl, SA_ZPL_PARENT(zfsvfs),
+	    &parent, sizeof (uint64_t))) != 0) {
+		ZFS_EXIT(zfsvfs);
+		return (error);
+	}
+	if (parent == zfsvfs->z_shares_dir) {
+		ZFS_EXIT(zfsvfs);
+		return (EPERM);
+	}
+
 	if (zfsvfs->z_utf8 && u8_validate(name,
 	    strlen(name), NULL, U8_VALIDATE_ENTIRE, &error) < 0) {
 		ZFS_EXIT(zfsvfs);
@@ -3772,7 +3794,6 @@ zfs_link(vnode_t *tdvp, vnode_t *svp, char *name, cred_t *cr,
 	if (flags & FIGNORECASE)
 		zf |= ZCILOOK;
 
-top:
 	/*
 	 * We do not support links between attributes and non-attributes
 	 * because of the potential security risk of creating links
@@ -3784,14 +3805,6 @@ zfs_link(vnode_t *tdvp, vnode_t *svp, char *name, cred_t *cr,
 		return (EINVAL);
 	}
 
-	/*
-	 * POSIX dictates that we return EPERM here.
-	 * Better choices include ENOTSUP or EISDIR.
-	 */
-	if (svp->v_type == VDIR) {
-		ZFS_EXIT(zfsvfs);
-		return (EPERM);
-	}
 
 	if (szp->z_uid != crgetuid(cr) &&
 	    secpolicy_basic_link(cr) != 0) {
@@ -3804,6 +3817,7 @@ zfs_link(vnode_t *tdvp, vnode_t *svp, char *name, cred_t *cr,
 		return (error);
 	}
 
+top:
 	/*
 	 * Attempt to lock directory; fail if entry already exists.
 	 */