NLM: Decode "priv" argument of NLMPROC_SM_NOTIFY as an opaque

The NLM XDR decoders for the NLMPROC_SM_NOTIFY procedure should treat
their "priv" argument truly as an opaque, as defined by the protocol,
and let the upper layers figure out what is in it.

This will make it easier to modify the contents and interpretation of
the "priv" argument, and keep knowledge about what's in "priv" local
to fs/lockd/mon.c.

For now, the NLM and NSM implementations should behave exactly as they
did before.

The formation of the address of the rebooted host in
nlm_host_rebooted() may look a little strange, but it is the inverse
of how nsm_init_private() forms the private cookie.  Plus, it's
going away soon anyway.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

4 files changed, 10 insertions, 9 deletions

diff --git a/fs/lockd/host.c b/fs/lockd/host.c
index ed103387964d..dc41e46ef74c 100644
--- a/fs/lockd/host.c
+++ b/fs/lockd/host.c
@@ -453,9 +453,10 @@ void nlm_release_host(struct nlm_host *host)
  */
 void nlm_host_rebooted(const struct nlm_reboot *info)
 {
+        __be32 *p = (__be32 *)&info->priv.data;
         const struct sockaddr_in sin = {
                 .sin_family             = AF_INET,
-                .sin_addr.s_addr        = info->addr,
+                .sin_addr.s_addr        = *p,
         };
         struct hlist_head *chain;
         struct hlist_node *pos;
diff --git a/fs/lockd/xdr.c b/fs/lockd/xdr.c
index 1f226290c67c..4cc7d01a1eb5 100644
--- a/fs/lockd/xdr.c
+++ b/fs/lockd/xdr.c
@@ -349,8 +349,8 @@ nlmsvc_decode_reboot(struct svc_rqst *rqstp, __be32 *p, struct nlm_reboot *argp)
         if (!(p = xdr_decode_string_inplace(p, &argp->mon, &argp->len, SM_MAXSTRLEN)))
                 return 0;
         argp->state = ntohl(*p++);
-        /* Preserve the address in network byte order */
-        argp->addr = *p++;
+        memcpy(&argp->priv.data, p, sizeof(argp->priv.data));
+        p += XDR_QUADLEN(SM_PRIV_SIZE);
         return xdr_argsize_check(rqstp, p);
 }
 
diff --git a/fs/lockd/xdr4.c b/fs/lockd/xdr4.c
index 50c493a8ad8e..61d1714a470e 100644
--- a/fs/lockd/xdr4.c
+++ b/fs/lockd/xdr4.c
@@ -356,8 +356,8 @@ nlm4svc_decode_reboot(struct svc_rqst *rqstp, __be32 *p, struct nlm_reboot *argp
         if (!(p = xdr_decode_string_inplace(p, &argp->mon, &argp->len, SM_MAXSTRLEN)))
                 return 0;
         argp->state = ntohl(*p++);
-        /* Preserve the address in network byte order */
-        argp->addr  = *p++;
+        memcpy(&argp->priv.data, p, sizeof(argp->priv.data));
+        p += XDR_QUADLEN(SM_PRIV_SIZE);
         return xdr_argsize_check(rqstp, p);
 }
 
diff --git a/include/linux/lockd/xdr.h b/include/linux/lockd/xdr.h
index 6b5199263858..6338866222a8 100644
--- a/include/linux/lockd/xdr.h
+++ b/include/linux/lockd/xdr.h
@@ -83,10 +83,10 @@ struct nlm_res {
  * statd callback when client has rebooted
  */
 struct nlm_reboot {
-        char *          mon;
-        unsigned int    len;
-        u32             state;
-        __be32          addr;
+        char                    *mon;
+        unsigned int            len;
+        u32                     state;
+        struct nsm_private      priv;
 };
 
 /*