NLM: fix source address of callback to client

Use the destination address of the original NLM request as the
source address in callbacks to the client.

Signed-off-by: Frank van Maarseveen <frankvm@frankvm.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

2 files changed, 20 insertions, 8 deletions

diff --git a/fs/lockd/host.c b/fs/lockd/host.c
index c252a1c95857..572601e98dcd 100644
--- a/fs/lockd/host.c
+++ b/fs/lockd/host.c
@@ -44,9 +44,8 @@ static struct nsm_handle *	nsm_find(const struct sockaddr_in *sin,
  */
 static struct nlm_host *
 nlm_lookup_host(int server, const struct sockaddr_in *sin,
-                                        int proto, int version,
-                                        const char *hostname,
-                                        int hostname_len)
+                int proto, int version, const char *hostname,
+                int hostname_len, const struct sockaddr_in *ssin)
 {
         struct hlist_head *chain;
         struct hlist_node *pos;
@@ -54,7 +53,9 @@ nlm_lookup_host(int server, const struct sockaddr_in *sin,
         struct nsm_handle *nsm = NULL;
         int             hash;
 
-        dprintk("lockd: nlm_lookup_host(%u.%u.%u.%u, p=%d, v=%d, my role=%s, name=%.*s)\n",
+        dprintk("lockd: nlm_lookup_host("NIPQUAD_FMT"->"NIPQUAD_FMT
+                        ", p=%d, v=%d, my role=%s, name=%.*s)\n",
+                        NIPQUAD(ssin->sin_addr.s_addr),
                         NIPQUAD(sin->sin_addr.s_addr), proto, version,
                         server? "server" : "client",
                         hostname_len,
@@ -91,6 +92,8 @@ nlm_lookup_host(int server, const struct sockaddr_in *sin,
                         continue;
                 if (host->h_server != server)
                         continue;
+                if (!nlm_cmp_addr(&host->h_saddr, ssin))
+                        continue;
 
                 /* Move to head of hash chain. */
                 hlist_del(&host->h_hash);
@@ -118,6 +121,7 @@ nlm_lookup_host(int server, const struct sockaddr_in *sin,
         host->h_name       = nsm->sm_name;
         host->h_addr       = *sin;
         host->h_addr.sin_port = 0;      /* ouch! */
+        host->h_saddr      = *ssin;
         host->h_version    = version;
         host->h_proto      = proto;
         host->h_rpcclnt    = NULL;
@@ -174,8 +178,10 @@ struct nlm_host *
 nlmclnt_lookup_host(const struct sockaddr_in *sin, int proto, int version,
                         const char *hostname, int hostname_len)
 {
+        struct sockaddr_in ssin = {0};
+
         return nlm_lookup_host(0, sin, proto, version,
-                               hostname, hostname_len);
+                               hostname, hostname_len, &ssin);
 }
 
 /*
@@ -185,9 +191,12 @@ struct nlm_host *
 nlmsvc_lookup_host(struct svc_rqst *rqstp,
                         const char *hostname, int hostname_len)
 {
+        struct sockaddr_in ssin = {0};
+
+        ssin.sin_addr = rqstp->rq_daddr.addr;
         return nlm_lookup_host(1, svc_addr_in(rqstp),
                                rqstp->rq_prot, rqstp->rq_vers,
-                               hostname, hostname_len);
+                               hostname, hostname_len, &ssin);
 }
 
 /*
@@ -198,8 +207,9 @@ nlm_bind_host(struct nlm_host *host)
 {
         struct rpc_clnt *clnt;
 
-        dprintk("lockd: nlm_bind_host(%08x)\n",
-                        (unsigned)ntohl(host->h_addr.sin_addr.s_addr));
+        dprintk("lockd: nlm_bind_host("NIPQUAD_FMT"->"NIPQUAD_FMT")\n",
+                        NIPQUAD(host->h_saddr.sin_addr),
+                        NIPQUAD(host->h_addr.sin_addr));
 
         /* Lock host handle */
         mutex_lock(&host->h_mutex);
@@ -226,6 +236,7 @@ nlm_bind_host(struct nlm_host *host)
                         .protocol       = host->h_proto,
                         .address        = (struct sockaddr *)&host->h_addr,
                         .addrsize       = sizeof(host->h_addr),
+                        .saddress       = (struct sockaddr *)&host->h_saddr,
                         .timeout        = &timeparms,
                         .servername     = host->h_name,
                         .program        = &nlm_program,
diff --git a/include/linux/lockd/lockd.h b/include/linux/lockd/lockd.h
index 05707e2fccae..e2d1ce36b367 100644
--- a/include/linux/lockd/lockd.h
+++ b/include/linux/lockd/lockd.h
@@ -39,6 +39,7 @@
 struct nlm_host {
         struct hlist_node       h_hash;         /* doubly linked list */
         struct sockaddr_in      h_addr;         /* peer address */
+        struct sockaddr_in      h_saddr;        /* our address (optional) */
         struct rpc_clnt *       h_rpcclnt;      /* RPC client to talk to peer */
         char *                  h_name;         /* remote hostname */
         u32                     h_version;      /* interface version */