svcrpc: don't byte-swap sk_reclen in place

Byte-swapping in place is always a little dubious.

Let's instead define this field to always be big-endian, and do the
swapping on demand where we need it.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

2 files changed, 22 insertions, 16 deletions

diff --git a/include/linux/sunrpc/svcsock.h b/include/linux/sunrpc/svcsock.h
index 92ad02f0dcc0..613cf42227aa 100644
--- a/include/linux/sunrpc/svcsock.h
+++ b/include/linux/sunrpc/svcsock.h
@@ -26,11 +26,21 @@ struct svc_sock {
         void                    (*sk_owspace)(struct sock *);
 
         /* private TCP part */
-        u32                     sk_reclen;      /* length of record */
+        __be32                  sk_reclen;      /* length of record */
         u32                     sk_tcplen;      /* current read length */
         struct page *           sk_pages[RPCSVC_MAXPAGES];      /* received data */
 };
 
+static inline u32 svc_sock_reclen(struct svc_sock *svsk)
+{
+        return ntohl(svsk->sk_reclen) & RPC_FRAGMENT_SIZE_MASK;
+}
+
+static inline u32 svc_sock_final_rec(struct svc_sock *svsk)
+{
+        return ntohl(svsk->sk_reclen) & RPC_LAST_STREAM_FRAGMENT;
+}
+
 /*
  * Function prototypes.
  */
diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index 03827cef1fa7..d50de2b95036 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -950,8 +950,7 @@ static int svc_tcp_recv_record(struct svc_sock *svsk, struct svc_rqst *rqstp)
                         return -EAGAIN;
                 }
 
-                svsk->sk_reclen = ntohl(svsk->sk_reclen);
-                if (!(svsk->sk_reclen & RPC_LAST_STREAM_FRAGMENT)) {
+                if (!(svc_sock_final_rec(svsk))) {
                         /* FIXME: technically, a record can be fragmented,
                          *  and non-terminal fragments will not have the top
                          *  bit set in the fragment length header.
@@ -961,21 +960,18 @@ static int svc_tcp_recv_record(struct svc_sock *svsk, struct svc_rqst *rqstp)
                         goto err_delete;
                 }
 
-                svsk->sk_reclen &= RPC_FRAGMENT_SIZE_MASK;
-                dprintk("svc: TCP record, %d bytes\n", svsk->sk_reclen);
-                if (svsk->sk_reclen > serv->sv_max_mesg) {
+                dprintk("svc: TCP record, %d bytes\n", svc_sock_reclen(svsk));
+                if (svc_sock_reclen(svsk) > serv->sv_max_mesg) {
                         net_notice_ratelimited("RPC: fragment too large: 0x%08lx\n",
-                                               (unsigned long)svsk->sk_reclen);
+                                        (unsigned long)svc_sock_reclen(svsk));
                         goto err_delete;
                 }
         }
 
-        if (svsk->sk_reclen < 8)
+        if (svc_sock_reclen(svsk) < 8)
                 goto err_delete; /* client is nuts. */
 
-        len = svsk->sk_reclen;
-
-        return len;
+        return svc_sock_reclen(svsk);
 error:
         dprintk("RPC: TCP recv_record got %d\n", len);
         return len;
@@ -1019,7 +1015,7 @@ static int receive_cb_reply(struct svc_sock *svsk, struct svc_rqst *rqstp)
         if (dst->iov_len < src->iov_len)
                 return -EAGAIN; /* whatever; just giving up. */
         memcpy(dst->iov_base, src->iov_base, src->iov_len);
-        xprt_complete_rqst(req->rq_task, svsk->sk_reclen);
+        xprt_complete_rqst(req->rq_task, rqstp->rq_arg.len);
         rqstp->rq_arg.len = 0;
         return 0;
 }
@@ -1064,12 +1060,12 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
                 goto error;
 
         base = svc_tcp_restore_pages(svsk, rqstp);
-        want = svsk->sk_reclen - base;
+        want = svc_sock_reclen(svsk) - base;
 
         vec = rqstp->rq_vec;
 
         pnum = copy_pages_to_kvecs(&vec[0], &rqstp->rq_pages[0],
-                                                svsk->sk_reclen);
+                                                svc_sock_reclen(svsk));
 
         rqstp->rq_respages = &rqstp->rq_pages[pnum];
 
@@ -1082,11 +1078,11 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
                 if (len < 0 && len != -EAGAIN)
                         goto err_other;
                 dprintk("svc: incomplete TCP record (%d of %d)\n",
-                        svsk->sk_tcplen, svsk->sk_reclen);
+                        svsk->sk_tcplen, svc_sock_reclen(svsk));
                 goto err_noclose;
         }
 
-        rqstp->rq_arg.len = svsk->sk_reclen;
+        rqstp->rq_arg.len = svc_sock_reclen(svsk);
         rqstp->rq_arg.page_base = 0;
         if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len) {
                 rqstp->rq_arg.head[0].iov_len = rqstp->rq_arg.len;