unmount-ncp.diff (see comments on kernel@)

[Csaba Henk <csaba.henk@xxxxxxx>]

# HG changeset patch
# User root@
# Node ID 758f5a725024e40c276e253651f9115aa4ba9fbe
# Parent  322bdf54fc0aeddb365a01452e57c144bf8986aa
imported patch ncp_unmount

diff -r 322bdf54fc0a -r 758f5a725024 sys/kern/vfs_syscalls.c
--- a/sys/kern/vfs_syscalls.c	Mon Jan  2 11:41:48 2006 +0000
+++ b/sys/kern/vfs_syscalls.c	Mon Jan  2 11:42:05 2006 +0000
@@ -453,7 +453,6 @@
 {
 	struct thread *td = curthread;
 	struct proc *p = td->td_proc;
-	struct vnode *vp;
 	struct mount *mp;
 	int error;
 	struct nlookupdata nd;
@@ -464,44 +463,42 @@
 	if (usermount == 0 && (error = suser(td)))
 		return (error);
 
-	vp = NULL;
 	error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
 	if (error == 0)
 		error = nlookup(&nd);
-	if (error == 0)
-		error = cache_vget(nd.nl_ncp, nd.nl_cred, LK_EXCLUSIVE, &vp);
+	if (error)
+		goto out;
+
+	mp = nd.nl_ncp->nc_mount;
+
+	/*
+	 * Only root, or the user that did the original mount is
+	 * permitted to unmount this filesystem.
+	 */
+	if ((mp->mnt_stat.f_owner != p->p_ucred->cr_uid) &&
+	    (error = suser(td)))
+		goto out;
+
+	/*
+	 * Don't allow unmounting the root file system.
+	 */
+	if (mp->mnt_flag & MNT_ROOTFS) {
+		error = EINVAL;
+		goto out;
+	}
+
+	/*
+	 * Must be the root of the filesystem
+	 */
+	if (! (nd.nl_ncp->nc_flag & NCF_MOUNTPT)) {
+		error = EINVAL;
+		goto out;
+	}
+
+out:
 	nlookup_done(&nd);
 	if (error)
 		return (error);
-
-	mp = vp->v_mount;
-
-	/*
-	 * Only root, or the user that did the original mount is
-	 * permitted to unmount this filesystem.
-	 */
-	if ((mp->mnt_stat.f_owner != p->p_ucred->cr_uid) &&
-	    (error = suser(td))) {
-		vput(vp);
-		return (error);
-	}
-
-	/*
-	 * Don't allow unmounting the root file system.
-	 */
-	if (mp->mnt_flag & MNT_ROOTFS) {
-		vput(vp);
-		return (EINVAL);
-	}
-
-	/*
-	 * Must be the root of the filesystem
-	 */
-	if ((vp->v_flag & VROOT) == 0) {
-		vput(vp);
-		return (EINVAL);
-	}
-	vput(vp);
 	return (dounmount(mp, uap->flags, td));
 }