Patch "NFSD: Update the NFSv2 diropres encoder to use struct xdr_stream" has been added to the 5.10-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    NFSD: Update the NFSv2 diropres encoder to use struct xdr_stream

to the 5.10-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     nfsd-update-the-nfsv2-diropres-encoder-to-use-struct.patch
and it can be found in the queue-5.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 0564cc939508910d46afe1205f130e23e9bd9be9
Author: Chuck Lever <chuck.lever@xxxxxxxxxx>
Date:   Fri Oct 23 16:44:16 2020 -0400

    NFSD: Update the NFSv2 diropres encoder to use struct xdr_stream
    
    [ Upstream commit e3b4ef221ac57c08341c97a10c8a81c041f76716 ]
    
    Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/fs/nfsd/nfsxdr.c b/fs/nfsd/nfsxdr.c
index 65c8f8f314443..989144b0d5be2 100644
--- a/fs/nfsd/nfsxdr.c
+++ b/fs/nfsd/nfsxdr.c
@@ -63,11 +63,17 @@ svcxdr_decode_fhandle(struct xdr_stream *xdr, struct svc_fh *fhp)
 	return true;
 }
 
-static __be32 *
-encode_fh(__be32 *p, struct svc_fh *fhp)
+static bool
+svcxdr_encode_fhandle(struct xdr_stream *xdr, const struct svc_fh *fhp)
 {
+	__be32 *p;
+
+	p = xdr_reserve_space(xdr, NFS_FHSIZE);
+	if (!p)
+		return false;
 	memcpy(p, &fhp->fh_handle.fh_base, NFS_FHSIZE);
-	return p + (NFS_FHSIZE>> 2);
+
+	return true;
 }
 
 static __be32 *
@@ -244,7 +250,7 @@ encode_fattr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp,
 	return p;
 }
 
-static int
+static bool
 svcxdr_encode_fattr(struct svc_rqst *rqstp, struct xdr_stream *xdr,
 		    const struct svc_fh *fhp, const struct kstat *stat)
 {
@@ -257,7 +263,7 @@ svcxdr_encode_fattr(struct svc_rqst *rqstp, struct xdr_stream *xdr,
 
 	p = xdr_reserve_space(xdr, XDR_UNIT * 17);
 	if (!p)
-		return 0;
+		return false;
 
 	*p++ = cpu_to_be32(nfs_ftypes[type >> 12]);
 	*p++ = cpu_to_be32((u32)stat->mode);
@@ -299,7 +305,7 @@ svcxdr_encode_fattr(struct svc_rqst *rqstp, struct xdr_stream *xdr,
 	p = encode_timeval(p, &time);
 	encode_timeval(p, &stat->ctime);
 
-	return 1;
+	return true;
 }
 
 /* Helper function for NFSv2 ACL code */
@@ -501,15 +507,21 @@ nfssvc_encode_attrstatres(struct svc_rqst *rqstp, __be32 *p)
 int
 nfssvc_encode_diropres(struct svc_rqst *rqstp, __be32 *p)
 {
+	struct xdr_stream *xdr = &rqstp->rq_res_stream;
 	struct nfsd_diropres *resp = rqstp->rq_resp;
 
-	*p++ = resp->status;
-	if (resp->status != nfs_ok)
-		goto out;
-	p = encode_fh(p, &resp->fh);
-	p = encode_fattr(rqstp, p, &resp->fh, &resp->stat);
-out:
-	return xdr_ressize_check(rqstp, p);
+	if (!svcxdr_encode_stat(xdr, resp->status))
+		return 0;
+	switch (resp->status) {
+	case nfs_ok:
+		if (!svcxdr_encode_fhandle(xdr, &resp->fh))
+			return 0;
+		if (!svcxdr_encode_fattr(rqstp, xdr, &resp->fh, &resp->stat))
+			return 0;
+		break;
+	}
+
+	return 1;
 }
 
 int