---

yaml
---
r: 124763
b: refs/heads/master
c: 34769fc
h: refs/heads/master
i:
  124761: 03676ea
  124759: 3264ca7
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 5b7ddd4a7b19f913901140ef7807dbf5e2b301cd
+refs/heads/master: 34769fc488b463cb753fc632f8f5ba56c918b7cb

trunk/net/sunrpc/auth_gss/auth_gss.c

@@ -72,7 +72,13 @@ struct gss_auth {
 	struct gss_api_mech *mech;
 	enum rpc_gss_svc service;
 	struct rpc_clnt *client;
-	struct dentry *dentry;
+	/*
+	 * There are two upcall pipes; dentry[1], named "gssd", is used
+	 * for the new text-based upcall; dentry[0] is named after the
+	 * mechanism (for example, "krb5") and exists for
+	 * backwards-compatibility with older gssd's.
+	 */
+	struct dentry *dentry[2];
 };
 
 /* pipe_version >= 0 if and only if someone has a pipe open. */
@@ -83,7 +89,8 @@ static struct rpc_wait_queue pipe_version_rpc_waitqueue;
 static DECLARE_WAIT_QUEUE_HEAD(pipe_version_waitqueue);
 
 static void gss_free_ctx(struct gss_cl_ctx *);
-static struct rpc_pipe_ops gss_upcall_ops;
+static struct rpc_pipe_ops gss_upcall_ops_v0;
+static struct rpc_pipe_ops gss_upcall_ops_v1;
 
 static inline struct gss_cl_ctx *
 gss_get_ctx(struct gss_cl_ctx *ctx)
@@ -227,6 +234,7 @@ gss_fill_context(const void *p, const void *end, struct gss_cl_ctx *ctx, struct
 	return p;
 }
 
+#define UPCALL_BUF_LEN 128
 
 struct gss_upcall_msg {
 	atomic_t count;
@@ -238,6 +246,7 @@ struct gss_upcall_msg {
 	struct rpc_wait_queue rpc_waitqueue;
 	wait_queue_head_t waitqueue;
 	struct gss_cl_ctx *ctx;
+	char databuf[UPCALL_BUF_LEN];
 };
 
 static int get_pipe_version(void)
@@ -247,7 +256,7 @@ static int get_pipe_version(void)
 	spin_lock(&pipe_version_lock);
 	if (pipe_version >= 0) {
 		atomic_inc(&pipe_users);
-		ret = 0;
+		ret = pipe_version;
 	} else
 		ret = -EAGAIN;
 	spin_unlock(&pipe_version_lock);
@@ -353,6 +362,29 @@ gss_upcall_callback(struct rpc_task *task)
 	gss_release_msg(gss_msg);
 }
 
+static void gss_encode_v0_msg(struct gss_upcall_msg *gss_msg)
+{
+	gss_msg->msg.data = &gss_msg->uid;
+	gss_msg->msg.len = sizeof(gss_msg->uid);
+}
+
+static void gss_encode_v1_msg(struct gss_upcall_msg *gss_msg)
+{
+	gss_msg->msg.len = sprintf(gss_msg->databuf, "mech=%s uid=%d\n",
+				   gss_msg->auth->mech->gm_name,
+				   gss_msg->uid);
+	gss_msg->msg.data = gss_msg->databuf;
+	BUG_ON(gss_msg->msg.len > UPCALL_BUF_LEN);
+}
+
+static void gss_encode_msg(struct gss_upcall_msg *gss_msg)
+{
+	if (pipe_version == 0)
+		gss_encode_v0_msg(gss_msg);
+	else /* pipe_version == 1 */
+		gss_encode_v1_msg(gss_msg);
+}
+
 static inline struct gss_upcall_msg *
 gss_alloc_msg(struct gss_auth *gss_auth, uid_t uid)
 {
@@ -367,15 +399,14 @@ gss_alloc_msg(struct gss_auth *gss_auth, uid_t uid)
 		kfree(gss_msg);
 		return ERR_PTR(vers);
 	}
-	gss_msg->inode = RPC_I(gss_auth->dentry->d_inode);
+	gss_msg->inode = RPC_I(gss_auth->dentry[vers]->d_inode);
 	INIT_LIST_HEAD(&gss_msg->list);
 	rpc_init_wait_queue(&gss_msg->rpc_waitqueue, "RPCSEC_GSS upcall waitq");
 	init_waitqueue_head(&gss_msg->waitqueue);
 	atomic_set(&gss_msg->count, 1);
-	gss_msg->msg.data = &gss_msg->uid;
-	gss_msg->msg.len = sizeof(gss_msg->uid);
 	gss_msg->uid = uid;
 	gss_msg->auth = gss_auth;
+	gss_encode_msg(gss_msg);
 	return gss_msg;
 }
 
@@ -613,18 +644,36 @@ gss_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
 	return err;
 }
 
-static int
-gss_pipe_open(struct inode *inode)
+static int gss_pipe_open(struct inode *inode, int new_version)
 {
+	int ret = 0;
+
 	spin_lock(&pipe_version_lock);
 	if (pipe_version < 0) {
-		pipe_version = 0;
+		/* First open of any gss pipe determines the version: */
+		pipe_version = new_version;
 		rpc_wake_up(&pipe_version_rpc_waitqueue);
 		wake_up(&pipe_version_waitqueue);
+	} else if (pipe_version != new_version) {
+		/* Trying to open a pipe of a different version */
+		ret = -EBUSY;
+		goto out;
 	}
 	atomic_inc(&pipe_users);
+out:
 	spin_unlock(&pipe_version_lock);
-	return 0;
+	return ret;
+
+}
+
+static int gss_pipe_open_v0(struct inode *inode)
+{
+	return gss_pipe_open(inode, 0);
+}
+
+static int gss_pipe_open_v1(struct inode *inode)
+{
+	return gss_pipe_open(inode, 1);
 }
 
 static void
@@ -702,20 +751,38 @@ gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
 	atomic_set(&auth->au_count, 1);
 	kref_init(&gss_auth->kref);
 
-	gss_auth->dentry = rpc_mkpipe(clnt->cl_dentry, gss_auth->mech->gm_name,
-			clnt, &gss_upcall_ops, RPC_PIPE_WAIT_FOR_OPEN);
-	if (IS_ERR(gss_auth->dentry)) {
-		err = PTR_ERR(gss_auth->dentry);
+	/*
+	 * Note: if we created the old pipe first, then someone who
+	 * examined the directory at the right moment might conclude
+	 * that we supported only the old pipe.  So we instead create
+	 * the new pipe first.
+	 */
+	gss_auth->dentry[1] = rpc_mkpipe(clnt->cl_dentry,
+					 "gssd",
+					 clnt, &gss_upcall_ops_v1,
+					 RPC_PIPE_WAIT_FOR_OPEN);
+	if (IS_ERR(gss_auth->dentry[1])) {
+		err = PTR_ERR(gss_auth->dentry[1]);
 		goto err_put_mech;
 	}
 
+	gss_auth->dentry[0] = rpc_mkpipe(clnt->cl_dentry,
+					 gss_auth->mech->gm_name,
+					 clnt, &gss_upcall_ops_v0,
+					 RPC_PIPE_WAIT_FOR_OPEN);
+	if (IS_ERR(gss_auth->dentry[0])) {
+		err = PTR_ERR(gss_auth->dentry[0]);
+		goto err_unlink_pipe_1;
+	}
 	err = rpcauth_init_credcache(auth);
 	if (err)
-		goto err_unlink_pipe;
+		goto err_unlink_pipe_0;
 
 	return auth;
-err_unlink_pipe:
-	rpc_unlink(gss_auth->dentry);
+err_unlink_pipe_0:
+	rpc_unlink(gss_auth->dentry[0]);
+err_unlink_pipe_1:
+	rpc_unlink(gss_auth->dentry[1]);
 err_put_mech:
 	gss_mech_put(gss_auth->mech);
 err_free:
@@ -728,7 +795,8 @@ gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
 static void
 gss_free(struct gss_auth *gss_auth)
 {
-	rpc_unlink(gss_auth->dentry);
+	rpc_unlink(gss_auth->dentry[1]);
+	rpc_unlink(gss_auth->dentry[0]);
 	gss_mech_put(gss_auth->mech);
 
 	kfree(gss_auth);
@@ -1419,11 +1487,19 @@ static const struct rpc_credops gss_nullops = {
 	.crunwrap_resp	= gss_unwrap_resp,
 };
 
-static struct rpc_pipe_ops gss_upcall_ops = {
+static struct rpc_pipe_ops gss_upcall_ops_v0 = {
+	.upcall		= gss_pipe_upcall,
+	.downcall	= gss_pipe_downcall,
+	.destroy_msg	= gss_pipe_destroy_msg,
+	.open_pipe	= gss_pipe_open_v0,
+	.release_pipe	= gss_pipe_release,
+};
+
+static struct rpc_pipe_ops gss_upcall_ops_v1 = {
 	.upcall		= gss_pipe_upcall,
 	.downcall	= gss_pipe_downcall,
 	.destroy_msg	= gss_pipe_destroy_msg,
-	.open_pipe	= gss_pipe_open,
+	.open_pipe	= gss_pipe_open_v1,
 	.release_pipe	= gss_pipe_release,
 };