nfsd4: fix decoding of compounds across page boundaries
commit 247500820ebd02ad87525db5d9b199e5b66f6636 upstream.
A freebsd NFSv4.0 client was getting rare IO errors expanding a tarball.
A network trace showed the server returning BAD_XDR on the final getattr
of a getattr+write+getattr compound. The final getattr started on a
page boundary.
I believe the Linux client ignores errors on the post-write getattr, and
that that's why we haven't seen this before.
Reported-by: Rick Macklem <rmacklem@uoguelph.ca>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 6cd86e0..582321a 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -162,8 +162,8 @@
*/
memcpy(p, argp->p, avail);
/* step to next page */
- argp->p = page_address(argp->pagelist[0]);
argp->pagelist++;
+ argp->p = page_address(argp->pagelist[0]);
if (argp->pagelen < PAGE_SIZE) {
argp->end = argp->p + (argp->pagelen>>2);
argp->pagelen = 0;