6.5-stable review patch. If anyone has any objections, please let me know.
------------------
From: Chuck Lever <chuck.lever@xxxxxxxxxx>
commit 49cecd8628a9855cd993792a0377559ea32d5e7c upstream.
When inserting a DRC-cached response into the reply buffer, ensure
that the reply buffer's xdr_stream is updated properly. Otherwise
the server will send a garbage response.
Cc: stable@xxxxxxxxxxxxxxx # v6.3+
Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
Tested-by: Jeff Layton <jlayton@xxxxxxxxxx>
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/nfsd/nfscache.c | 21 +++++++--------------
1 file changed, 7 insertions(+), 14 deletions(-)
--- a/fs/nfsd/nfscache.c
+++ b/fs/nfsd/nfscache.c
@@ -582,24 +582,17 @@ void nfsd_cache_update(struct svc_rqst *
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];
+ __be32 *p;
- 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;
+ 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;
}
/*
