svn commit: r220101 - head/sys/kern

[Konstantin Belousov]

Author: kib
Date: Mon Mar 28 13:21:26 2011
New Revision: 220101
URL: http://svn.freebsd.org/changeset/base/220101

Log:
  Handle zero length in copyout_unmap().
  
  Submitted by:	John Wehle <john feith com>
  MFC after:	2 weeks

Modified:
  head/sys/kern/subr_uio.c

Modified: head/sys/kern/subr_uio.c
==============================================================================
--- head/sys/kern/subr_uio.c	Mon Mar 28 12:48:33 2011	(r220100)
+++ head/sys/kern/subr_uio.c	Mon Mar 28 13:21:26 2011	(r220101)
@@ -498,6 +498,9 @@ copyout_unmap(struct thread *td, vm_offs
 	vm_map_t map;
 	vm_size_t size;
     
+	if (sz == 0)
+		return (0);
+
 	map = &td->td_proc->p_vmspace->vm_map;
 	size = (vm_size_t) round_page(sz);