svn commit: r291291 - head/sys/kern

[Andrey V. Elsukov]

Author: ae
Date: Wed Nov 25 07:14:58 2015
New Revision: 291291
URL: https://svnweb.freebsd.org/changeset/base/291291

Log:
  Check that hhk_helper pointer isn't NULL before access.
  
  It isn't forbidden to use NULL pointer for hook_helper in hookinfo
  structure when hhook_add_hook() adds new helper hook.

Modified:
  head/sys/kern/kern_hhook.c

Modified: head/sys/kern/kern_hhook.c
==============================================================================
--- head/sys/kern/kern_hhook.c	Wed Nov 25 04:13:28 2015	(r291290)
+++ head/sys/kern/kern_hhook.c	Wed Nov 25 07:14:58 2015	(r291291)
@@ -101,7 +101,8 @@ hhook_run_hooks(struct hhook_head *hhh, 
 
 	HHH_RLOCK(hhh, &rmpt);
 	STAILQ_FOREACH(hhk, &hhh->hhh_hooks, hhk_next) {
-		if (hhk->hhk_helper->h_flags & HELPER_NEEDS_OSD) {
+		if (hhk->hhk_helper != NULL &&
+		    hhk->hhk_helper->h_flags & HELPER_NEEDS_OSD) {
 			hdata = osd_get(OSD_KHELP, hosd, hhk->hhk_helper->h_id);
 			if (hdata == NULL)
 				continue;