[src/trunk]: src/sys/kern Reorder code to avoid use-after-free on error. From...

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

details:   https://anonhg.NetBSD.org/src/rev/81efb8935025
branches:  trunk
changeset: 325911:81efb8935025
user:      christos <christos%NetBSD.org@localhost>
date:      Sat Jan 11 16:31:20 2014 +0000

description:
Reorder code to avoid use-after-free on error. From Maxime Villard

diffstat:

 sys/kern/kern_verifiedexec.c |  28 ++++++++++++++--------------
 1 files changed, 14 insertions(+), 14 deletions(-)

diffs (56 lines):

diff -r 23c619eb7855 -r 81efb8935025 sys/kern/kern_verifiedexec.c
--- a/sys/kern/kern_verifiedexec.c      Sat Jan 11 15:51:02 2014 +0000
+++ b/sys/kern/kern_verifiedexec.c      Sat Jan 11 16:31:20 2014 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: kern_verifiedexec.c,v 1.131 2013/11/27 17:24:44 christos Exp $ */
+/*     $NetBSD: kern_verifiedexec.c,v 1.132 2014/01/11 16:31:20 christos Exp $ */
 
 /*-
  * Copyright (c) 2005, 2006 Elad Efrat <elad%NetBSD.org@localhost>
@@ -29,7 +29,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_verifiedexec.c,v 1.131 2013/11/27 17:24:44 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_verifiedexec.c,v 1.132 2014/01/11 16:31:20 christos Exp $");
 
 #include "opt_veriexec.h"
 
@@ -1309,18 +1309,6 @@
        vfe->npages = 0;
        vfe->last_page_size = 0;
 
-       vte = veriexec_table_lookup(vp->v_mount);
-       if (vte == NULL)
-               vte = veriexec_table_add(l, vp->v_mount);
-
-       /* XXX if we bail below this, we might want to gc newly created vtes. */
-
-       error = fileassoc_add(vp, veriexec_hook, vfe);
-       if (error)
-               goto unlock_out;
-
-       vte->vte_count++;
-
        if (prop_bool_true(prop_dictionary_get(dict, "eval-on-load")) ||
            (vfe->type & VERIEXEC_UNTRUSTED)) {
                u_char *digest;
@@ -1342,6 +1330,18 @@
                kmem_free(digest, vfe->ops->hash_len);
        }
 
+       vte = veriexec_table_lookup(vp->v_mount);
+       if (vte == NULL)
+               vte = veriexec_table_add(l, vp->v_mount);
+
+       /* XXX if we bail below this, we might want to gc newly created vtes. */
+
+       error = fileassoc_add(vp, veriexec_hook, vfe);
+       if (error)
+               goto unlock_out;
+
+       vte->vte_count++;
+
        veriexec_file_report(NULL, "New entry.", file, NULL, REPORT_DEBUG);
        veriexec_bypass = 0;