Patch "nfsd4: minor NFSv2/v3 write decoding cleanup" has been added to the 4.10-stable tree

Patch "nfsd4: minor NFSv2/v3 write decoding cleanup" has been added to the 4.10-stable tree

[gregkh]

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

    nfsd4: minor NFSv2/v3 write decoding cleanup

to the 4.10-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:
     nfsd4-minor-nfsv2-v3-write-decoding-cleanup.patch
and it can be found in the queue-4.10 subdirectory.

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


>From db44bac41bbfc0c0d9dd943092d8bded3c9db19b Mon Sep 17 00:00:00 2001
From: "J. Bruce Fields" <bfields@redhat.com>
Date: Tue, 25 Apr 2017 16:21:34 -0400
Subject: nfsd4: minor NFSv2/v3 write decoding cleanup

From: J. Bruce Fields <bfields@redhat.com>

commit db44bac41bbfc0c0d9dd943092d8bded3c9db19b upstream.

Use a couple shortcuts that will simplify a following bugfix.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 fs/nfsd/nfs3xdr.c |    9 +++++----
 fs/nfsd/nfsxdr.c  |    8 ++++----
 2 files changed, 9 insertions(+), 8 deletions(-)

--- a/fs/nfsd/nfs3xdr.c
+++ b/fs/nfsd/nfs3xdr.c
@@ -358,6 +358,8 @@ nfs3svc_decode_writeargs(struct svc_rqst
 {
 	unsigned int len, v, hdr, dlen;
 	u32 max_blocksize = svc_max_payload(rqstp);
+	struct kvec *head = rqstp->rq_arg.head;
+	struct kvec *tail = rqstp->rq_arg.tail;
 
 	p = decode_fh(p, &args->fh);
 	if (!p)
@@ -377,9 +379,8 @@ nfs3svc_decode_writeargs(struct svc_rqst
 	 * Check to make sure that we got the right number of
 	 * bytes.
 	 */
-	hdr = (void*)p - rqstp->rq_arg.head[0].iov_base;
-	dlen = rqstp->rq_arg.head[0].iov_len + rqstp->rq_arg.page_len
-		+ rqstp->rq_arg.tail[0].iov_len - hdr;
+	hdr = (void*)p - head->iov_base;
+	dlen = head->iov_len + rqstp->rq_arg.page_len + tail->iov_len - hdr;
 	/*
 	 * Round the length of the data which was specified up to
 	 * the next multiple of XDR units and then compare that
@@ -396,7 +397,7 @@ nfs3svc_decode_writeargs(struct svc_rqst
 		len = args->len = max_blocksize;
 	}
 	rqstp->rq_vec[0].iov_base = (void*)p;
-	rqstp->rq_vec[0].iov_len = rqstp->rq_arg.head[0].iov_len - hdr;
+	rqstp->rq_vec[0].iov_len = head->iov_len - hdr;
 	v = 0;
 	while (len > rqstp->rq_vec[v].iov_len) {
 		len -= rqstp->rq_vec[v].iov_len;
--- a/fs/nfsd/nfsxdr.c
+++ b/fs/nfsd/nfsxdr.c
@@ -280,6 +280,7 @@ nfssvc_decode_writeargs(struct svc_rqst
 					struct nfsd_writeargs *args)
 {
 	unsigned int len, hdr, dlen;
+	struct kvec *head = rqstp->rq_arg.head;
 	int v;
 
 	p = decode_fh(p, &args->fh);
@@ -300,9 +301,8 @@ nfssvc_decode_writeargs(struct svc_rqst
 	 * Check to make sure that we got the right number of
 	 * bytes.
 	 */
-	hdr = (void*)p - rqstp->rq_arg.head[0].iov_base;
-	dlen = rqstp->rq_arg.head[0].iov_len + rqstp->rq_arg.page_len
-		- hdr;
+	hdr = (void*)p - head->iov_base;
+	dlen = head->iov_len + rqstp->rq_arg.page_len - hdr;
 
 	/*
 	 * Round the length of the data which was specified up to
@@ -316,7 +316,7 @@ nfssvc_decode_writeargs(struct svc_rqst
 		return 0;
 
 	rqstp->rq_vec[0].iov_base = (void*)p;
-	rqstp->rq_vec[0].iov_len = rqstp->rq_arg.head[0].iov_len - hdr;
+	rqstp->rq_vec[0].iov_len = head->iov_len - hdr;
 	v = 0;
 	while (len > rqstp->rq_vec[v].iov_len) {
 		len -= rqstp->rq_vec[v].iov_len;


Patches currently in stable-queue which might be from bfields@redhat.com are

queue-4.10/nfsd-check-for-oversized-nfsv2-v3-arguments.patch
queue-4.10/nfsd4-minor-nfsv2-v3-write-decoding-cleanup.patch
queue-4.10/nfsd-stricter-decoding-of-write-like-nfsv2-v3-ops.patch