svn commit: r326699 - stable/11/sys/vm

[Mark Johnston]

Author: markj
Date: Fri Dec  8 17:16:35 2017
New Revision: 326699
URL: https://svnweb.freebsd.org/changeset/base/326699

Log:
  MFC r326371:
  Verify the object/vnode association after vget() in vm_pageout_clean().

Modified:
  stable/11/sys/vm/vm_pageout.c
Directory Properties:
  stable/11/   (props changed)

Modified: stable/11/sys/vm/vm_pageout.c
==============================================================================
--- stable/11/sys/vm/vm_pageout.c	Fri Dec  8 17:15:20 2017	(r326698)
+++ stable/11/sys/vm/vm_pageout.c	Fri Dec  8 17:16:35 2017	(r326699)
@@ -617,7 +617,17 @@ vm_pageout_clean(vm_page_t m, int *numpagedout)
 			goto unlock_mp;
 		}
 		VM_OBJECT_WLOCK(object);
+
+		/*
+		 * Ensure that the object and vnode were not disassociated
+		 * while locks were dropped.
+		 */
+		if (vp->v_object != object) {
+			error = ENOENT;
+			goto unlock_all;
+		}
 		vm_page_lock(m);
+
 		/*
 		 * While the object and page were unlocked, the page
 		 * may have been: