[src/trunk]: src/sys/kern Apply fix from hannken to ensure that VOP_ACCESS() ...

[njoly <njoly%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/0920c45a46d0
branches:  trunk
changeset: 782990:0920c45a46d0
user:      njoly <njoly%NetBSD.org@localhost>
date:      Fri Nov 30 13:26:37 2012 +0000

description:
Apply fix from hannken to ensure that VOP_ACCESS() is called on a
locked vnode for fd_nameiat(), fd_nameiat_simple() and do_sys_openat().
Fix both PR/47226 and PR/47255.

diffstat:

 sys/kern/vfs_syscalls.c |  10 ++++++++--
 1 files changed, 8 insertions(+), 2 deletions(-)

diffs (48 lines):

diff -r f88560644d72 -r 0920c45a46d0 sys/kern/vfs_syscalls.c
--- a/sys/kern/vfs_syscalls.c   Fri Nov 30 10:14:18 2012 +0000
+++ b/sys/kern/vfs_syscalls.c   Fri Nov 30 13:26:37 2012 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: vfs_syscalls.c,v 1.461 2012/11/19 15:01:17 martin Exp $        */
+/*     $NetBSD: vfs_syscalls.c,v 1.462 2012/11/30 13:26:37 njoly Exp $ */
 
 /*-
  * Copyright (c) 2008, 2009 The NetBSD Foundation, Inc.
@@ -70,7 +70,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: vfs_syscalls.c,v 1.461 2012/11/19 15:01:17 martin Exp $");
+__KERNEL_RCSID(0, "$NetBSD: vfs_syscalls.c,v 1.462 2012/11/30 13:26:37 njoly Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_fileassoc.h"
@@ -182,7 +182,9 @@
                        goto out;
 
                if (!(dfp->f_flag & FSEARCH)) {
+                       vn_lock(dfp->f_data, LK_EXCLUSIVE);
                        error = VOP_ACCESS(dfp->f_data, VEXEC, l->l_cred);
+                       VOP_UNLOCK(dfp->f_data);
                        if (error)
                                goto cleanup;
                }
@@ -212,7 +214,9 @@
                        goto out;
 
                if (!(dfp->f_flag & FSEARCH)) {
+                       vn_lock(dfp->f_data, LK_EXCLUSIVE);
                        error = VOP_ACCESS(dfp->f_data, VEXEC, l->l_cred);
+                       VOP_UNLOCK(dfp->f_data);
                        if (error)
                                goto cleanup;
                }
@@ -1660,7 +1664,9 @@
                dvp = dfp->f_data;
 
                if (!(dfp->f_flag & FSEARCH)) {
+                       vn_lock(dfp->f_data, LK_EXCLUSIVE);
                        error = VOP_ACCESS(dfp->f_data, VEXEC, l->l_cred);
+                       VOP_UNLOCK(dfp->f_data);
                        if (error)
                                goto cleanup;
                }