svn commit: r234957 - head/sys/security/mac_mls

[Christian Brueffer]

Author: brueffer
Date: Thu May  3 15:51:34 2012
New Revision: 234957
URL: http://svn.freebsd.org/changeset/base/234957

Log:
  Check vplabel for NULL before dereferencing it.  Fixes a panic
  when running atop with MAC_MLS enabled.
  
  Submitted by:	Richard Kojedzinszky <krichy at tvnetwork.hu>
  Reviewed by:	rwatson
  MFC after:	1 week

Modified:
  head/sys/security/mac_mls/mac_mls.c

Modified: head/sys/security/mac_mls/mac_mls.c
==============================================================================
--- head/sys/security/mac_mls/mac_mls.c	Thu May  3 15:37:05 2012	(r234956)
+++ head/sys/security/mac_mls/mac_mls.c	Thu May  3 15:51:34 2012	(r234957)
@@ -2028,6 +2028,9 @@ mls_system_check_acct(struct ucred *cred
 	if (!mls_enabled)
 		return (0);
 
+	if (vplabel == NULL)
+		return (0);
+
 	subj = SLOT(cred->cr_label);
 	obj = SLOT(vplabel);