svn commit: r316667 - head/sys/fs/nfsclient

[Rick Macklem]

Author: rmacklem
Date: Sun Apr  9 21:50:21 2017
New Revision: 316667
URL: https://svnweb.freebsd.org/changeset/base/316667

Log:
  Fix the NFSv4 client hndling of a stale write verifier in the Commit operation.
  
  When the NFSv4 client Commit operation encountered a stale write verifier,
  it erroneously mapped that to EIO. This could have caused recently written
  data to be lost when a server crashes/reboots between an UNSTABLE write
  and the subsequent commit. This patch fixes this.
  The bug was only for the NFSv4 client and did not affect NFSv3.
  
  Tested by:	cperciva
  PR:		215887
  MFC after:	2 weeks

Modified:
  head/sys/fs/nfsclient/nfs_clport.c

Modified: head/sys/fs/nfsclient/nfs_clport.c
==============================================================================
--- head/sys/fs/nfsclient/nfs_clport.c	Sun Apr  9 21:06:21 2017	(r316666)
+++ head/sys/fs/nfsclient/nfs_clport.c	Sun Apr  9 21:50:21 2017	(r316667)
@@ -1196,7 +1196,7 @@ nfscl_maperr(struct thread *td, int erro
 {
 	struct proc *p;
 
-	if (error < 10000)
+	if (error < 10000 || error >= NFSERR_STALEWRITEVERF)
 		return (error);
 	if (td != NULL)
 		p = td->td_proc;