From: Kirk McKusick <mckusick@ucbvax.Berkeley.EDU>
Date: Tue, 22 Nov 1994 09:42:10 +0000 (-0800)
Subject: return EBUSY if reference count on mount point is greater than 1 to
X-Git-Url: https://git.subgeniuskitty.com/unix-history/.git/commitdiff_plain/7a191a213efffdb6838c010998b9e95667a1f39b

return EBUSY if reference count on mount point is greater than 1 to
avoid problems in lookup from programs referencing the hidden vnode

SCCS-vsn: sys/kern/vfs_syscalls.c 8.25
---

diff --git a/usr/src/sys/kern/vfs_syscalls.c b/usr/src/sys/kern/vfs_syscalls.c
index c59ce72831..4577355cf1 100644
--- a/usr/src/sys/kern/vfs_syscalls.c
+++ b/usr/src/sys/kern/vfs_syscalls.c
@@ -9,7 +9,7 @@
  *
  * %sccs.include.redist.c%
  *
- *	@(#)vfs_syscalls.c	8.24 (Berkeley) %G%
+ *	@(#)vfs_syscalls.c	8.25 (Berkeley) %G%
  */
 
 #include <sys/param.h>
@@ -145,6 +145,10 @@ mount(p, uap, retval)
 		vput(vp);
 		return (ENODEV);
 	}
+	if (vp->v_usecount > 1 || vp->v_mountedhere != NULL) {
+		vput(vp);
+		return (EBUSY);
+	}
 
 	/*
 	 * Allocate and initialize the file system.
@@ -158,12 +162,6 @@ mount(p, uap, retval)
 		vput(vp);
 		return (error);
 	}
-	if (vp->v_mountedhere != NULL) {
-		vfs_unlock(mp);
-		free((caddr_t)mp, M_MOUNT);
-		vput(vp);
-		return (EBUSY);
-	}
 	vp->v_mountedhere = mp;
 	mp->mnt_vnodecovered = vp;
 	mp->mnt_stat.f_owner = p->p_ucred->cr_uid;