Adding upstream version 4.19.304.upstream/4.19.304upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 9 insertions, 0 deletions

diff --git a/fs/nfsd/blocklayoutxdr.c b/fs/nfsd/blocklayoutxdr.c
index 442543304..2455dc8be 100644
--- a/fs/nfsd/blocklayoutxdr.c
+++ b/fs/nfsd/blocklayoutxdr.c
@@ -82,6 +82,15 @@ nfsd4_block_encode_getdeviceinfo(struct xdr_stream *xdr,
 	int len = sizeof(__be32), ret, i;
 	__be32 *p;
 
+	/*
+	 * See paragraph 5 of RFC 8881 S18.40.3.
+	 */
+	if (!gdp->gd_maxcount) {
+		if (xdr_stream_encode_u32(xdr, 0) != XDR_UNIT)
+			return nfserr_resource;
+		return nfs_ok;
+	}
+
 	p = xdr_reserve_space(xdr, len + sizeof(__be32));
 	if (!p)
 		return nfserr_resource;