diff mbox series

[v2,2/3] NFSD: Update nfsd_cache_append() to use xdr_stream

Message ID 169963371954.5404.15414594140516305111.stgit@bazille.1015granger.net (mailing list archive)
State New, archived
Headers show
Series NFSD DRC fixes for v6.7-rc | expand

Commit Message

Chuck Lever Nov. 10, 2023, 4:28 p.m. UTC 
From: Chuck Lever <chuck.lever@oracle.com>

When inserting a DRC-cached response into the reply buffer, ensure
that the buffer's xdr_stream is updated properly. Otherwise the
server will send a garbage response.

This should have been part of last year's series to handle NFS
response encoding using the xdr_stream utilities.

Cc: <stable@vger.kernel.org> # v5.16+
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 fs/nfsd/nfscache.c |   23 ++++++++---------------
 1 file changed, 8 insertions(+), 15 deletions(-)
diff mbox series

Patch

diff --git a/fs/nfsd/nfscache.c b/fs/nfsd/nfscache.c
index fd56a52aa5fb..9046331e0e5e 100644
--- a/fs/nfsd/nfscache.c
+++ b/fs/nfsd/nfscache.c
@@ -641,24 +641,17 @@  void nfsd_cache_update(struct svc_rqst *rqstp, struct nfsd_cacherep *rp,
 	return;
 }
 
-/*
- * Copy cached reply to current reply buffer. Should always fit.
- * FIXME as reply is in a page, we should just attach the page, and
- * keep a refcount....
- */
 static int
 nfsd_cache_append(struct svc_rqst *rqstp, struct kvec *data)
 {
-	struct kvec	*vec = &rqstp->rq_res.head[0];
-
-	if (vec->iov_len + data->iov_len > PAGE_SIZE) {
-		printk(KERN_WARNING "nfsd: cached reply too large (%zd).\n",
-				data->iov_len);
-		return 0;
-	}
-	memcpy((char*)vec->iov_base + vec->iov_len, data->iov_base, data->iov_len);
-	vec->iov_len += data->iov_len;
-	return 1;
+	__be32 *p;
+
+	p = xdr_reserve_space(&rqstp->rq_res_stream, data->iov_len);
+	if (unlikely(!p))
+		return false;
+	memcpy(p, data->iov_base, data->iov_len);
+	xdr_commit_encode(&rqstp->rq_res_stream);
+	return true;
 }
 
 /*