svn commit: r198873 - head/sys/kern

[Edward Tomasz Napierala]

Author: trasz
Date: Wed Nov  4 06:47:14 2009
New Revision: 198873
URL: http://svn.freebsd.org/changeset/base/198873

Log:
  While VAPPEND without VWRITE makes sense for VOP_ACCESSX(9) (e.g. to check
  for the permission to create subdirectory (ACE4_ADD_SUBDIRECTORY)), it doesn't
  really make sense for VOP_ACCESS(9).  Also, many VOP_ACCESS(9) implementations
  don't expect that.  Make sure we don't confuse them.

Modified:
  head/sys/kern/vfs_default.c

Modified: head/sys/kern/vfs_default.c
==============================================================================
--- head/sys/kern/vfs_default.c	Wed Nov  4 04:41:03 2009	(r198872)
+++ head/sys/kern/vfs_default.c	Wed Nov  4 06:47:14 2009	(r198873)
@@ -353,6 +353,14 @@ vop_stdaccessx(struct vop_accessx_args *
 	if (accmode == 0)
 		return (0);
 
+	/*
+	 * Many VOP_APPEND implementations don't expect VAPPEND without VWRITE
+	 * being set, e.g. they check whether the filesystem is read-only only
+	 * when VWRITE is set.  Make sure we don't confuse them.
+	 */
+	if (accmode & VAPPEND)
+		accmode |= VWRITE;
+
 	return (VOP_ACCESS(ap->a_vp, accmode, ap->a_cred, ap->a_td));
 }