SUNRPC: Convert auth_gss pipe detection to work in namespaces

This seems to have been overlooked when we did the namespace
conversion. If a container is running a legacy version of rpc.gssd
then it will be disrupted if the global 'pipe_version' is set by a
container running the new version of rpc.gssd.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

3 files changed, 30 insertions, 19 deletions

diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index 3aff72f78bf2..fc2f78d6a9b4 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -87,8 +87,6 @@ struct gss_auth {
 };
 
 /* pipe_version >= 0 if and only if someone has a pipe open. */
-static int pipe_version = -1;
-static atomic_t pipe_users = ATOMIC_INIT(0);
 static DEFINE_SPINLOCK(pipe_version_lock);
 static struct rpc_wait_queue pipe_version_rpc_waitqueue;
 static DECLARE_WAIT_QUEUE_HEAD(pipe_version_waitqueue);
@@ -268,24 +266,27 @@ struct gss_upcall_msg {
         char databuf[UPCALL_BUF_LEN];
 };
 
-static int get_pipe_version(void)
+static int get_pipe_version(struct net *net)
 {
+        struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
         int ret;
 
         spin_lock(&pipe_version_lock);
-        if (pipe_version >= 0) {
-                atomic_inc(&pipe_users);
-                ret = pipe_version;
+        if (sn->pipe_version >= 0) {
+                atomic_inc(&sn->pipe_users);
+                ret = sn->pipe_version;
         } else
                 ret = -EAGAIN;
         spin_unlock(&pipe_version_lock);
         return ret;
 }
 
-static void put_pipe_version(void)
+static void put_pipe_version(struct net *net)
 {
-        if (atomic_dec_and_lock(&pipe_users, &pipe_version_lock)) {
-                pipe_version = -1;
+        struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
+
+        if (atomic_dec_and_lock(&sn->pipe_users, &pipe_version_lock)) {
+                sn->pipe_version = -1;
                 spin_unlock(&pipe_version_lock);
         }
 }
@@ -293,9 +294,10 @@ static void put_pipe_version(void)
 static void
 gss_release_msg(struct gss_upcall_msg *gss_msg)
 {
+        struct net *net = rpc_net_ns(gss_msg->auth->client);
         if (!atomic_dec_and_test(&gss_msg->count))
                 return;
-        put_pipe_version();
+        put_pipe_version(net);
         BUG_ON(!list_empty(&gss_msg->list));
         if (gss_msg->ctx != NULL)
                 gss_put_ctx(gss_msg->ctx);
@@ -441,7 +443,10 @@ static void gss_encode_msg(struct gss_upcall_msg *gss_msg,
                                 struct rpc_clnt *clnt,
                                 const char *service_name)
 {
-        if (pipe_version == 0)
+        struct net *net = rpc_net_ns(clnt);
+        struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
+
+        if (sn->pipe_version == 0)
                 gss_encode_v0_msg(gss_msg);
         else /* pipe_version == 1 */
                 gss_encode_v1_msg(gss_msg, clnt, service_name);
@@ -457,7 +462,7 @@ gss_alloc_msg(struct gss_auth *gss_auth, struct rpc_clnt *clnt,
         gss_msg = kzalloc(sizeof(*gss_msg), GFP_NOFS);
         if (gss_msg == NULL)
                 return ERR_PTR(-ENOMEM);
-        vers = get_pipe_version();
+        vers = get_pipe_version(rpc_net_ns(clnt));
         if (vers < 0) {
                 kfree(gss_msg);
                 return ERR_PTR(vers);
@@ -581,8 +586,8 @@ retry:
         gss_msg = gss_setup_upcall(gss_auth->client, gss_auth, cred);
         if (PTR_ERR(gss_msg) == -EAGAIN) {
                 err = wait_event_interruptible_timeout(pipe_version_waitqueue,
-                                pipe_version >= 0, timeout);
-                if (pipe_version < 0) {
+                                sn->pipe_version >= 0, timeout);
+                if (sn->pipe_version < 0) {
                         if (err == 0)
                                 sn->gssd_running = 0;
                         warn_gssd();
@@ -719,20 +724,22 @@ out:
 
 static int gss_pipe_open(struct inode *inode, int new_version)
 {
+        struct net *net = inode->i_sb->s_fs_info;
+        struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
         int ret = 0;
 
         spin_lock(&pipe_version_lock);
-        if (pipe_version < 0) {
+        if (sn->pipe_version < 0) {
                 /* First open of any gss pipe determines the version: */
-                pipe_version = new_version;
+                sn->pipe_version = new_version;
                 rpc_wake_up(&pipe_version_rpc_waitqueue);
                 wake_up(&pipe_version_waitqueue);
-        } else if (pipe_version != new_version) {
+        } else if (sn->pipe_version != new_version) {
                 /* Trying to open a pipe of a different version */
                 ret = -EBUSY;
                 goto out;
         }
-        atomic_inc(&pipe_users);
+        atomic_inc(&sn->pipe_users);
 out:
         spin_unlock(&pipe_version_lock);
         return ret;
@@ -752,6 +759,7 @@ static int gss_pipe_open_v1(struct inode *inode)
 static void
 gss_pipe_release(struct inode *inode)
 {
+        struct net *net = inode->i_sb->s_fs_info;
         struct rpc_pipe *pipe = RPC_I(inode)->pipe;
         struct gss_upcall_msg *gss_msg;
 
@@ -770,7 +778,7 @@ restart:
         }
         spin_unlock(&pipe->lock);
 
-        put_pipe_version();
+        put_pipe_version(net);
 }
 
 static void
diff --git a/net/sunrpc/netns.h b/net/sunrpc/netns.h
index 0827f641e8d7..74d948f5d5a1 100644
--- a/net/sunrpc/netns.h
+++ b/net/sunrpc/netns.h
@@ -28,6 +28,8 @@ struct sunrpc_net {
         wait_queue_head_t gssp_wq;
         struct rpc_clnt *gssp_clnt;
         int use_gss_proxy;
+        int pipe_version;
+        atomic_t pipe_users;
         struct proc_dir_entry *use_gssp_proc;
 
         unsigned int gssd_running;
diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c
index a370762e459d..e7ce4b3eb0bd 100644
--- a/net/sunrpc/rpc_pipe.c
+++ b/net/sunrpc/rpc_pipe.c
@@ -1073,6 +1073,7 @@ void rpc_pipefs_init_net(struct net *net)
 
         mutex_init(&sn->pipefs_sb_lock);
         sn->gssd_running = 1;
+        sn->pipe_version = -1;
 }
 
 /*