Commit 24750082 authored Jun 21, 2013 by J. Bruce Fields

nfsd4: fix decoding of compounds across page boundaries



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.

Cc: stable@vger.kernel.org
Reported-by: Rick Macklem <rmacklem@uoguelph.ca>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

parent 99c41515

fs/nfsd/nfs4xdr.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -167,8 +167,8 @@ static __be32 read_buf(struct nfsd4_compoundargs argp, u32 nbytes)
		*/
		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;