9 files changed, 508 insertions, 275 deletions

diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index fc2f78d6a9b..b6e440baccc 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -51,6 +51,7 @@
 #include <linux/sunrpc/rpc_pipe_fs.h>
 #include <linux/sunrpc/gss_api.h>
 #include <asm/uaccess.h>
+#include <linux/hashtable.h>
 
 #include "../netns.h"
 
@@ -62,6 +63,9 @@ static const struct rpc_credops gss_nullops;
 #define GSS_RETRY_EXPIRED 5
 static unsigned int gss_expired_cred_retry_delay = GSS_RETRY_EXPIRED;
 
+#define GSS_KEY_EXPIRE_TIMEO 240
+static unsigned int gss_key_expire_timeo = GSS_KEY_EXPIRE_TIMEO;
+
 #ifdef RPC_DEBUG
 # define RPCDBG_FACILITY	RPCDBG_AUTH
 #endif
@@ -71,25 +75,40 @@ static unsigned int gss_expired_cred_retry_delay = GSS_RETRY_EXPIRED;
  * using integrity (two 4-byte integers): */
 #define GSS_VERF_SLACK		100
 
+static DEFINE_HASHTABLE(gss_auth_hash_table, 4);
+static DEFINE_SPINLOCK(gss_auth_hash_lock);
+
+struct gss_pipe {
+	struct rpc_pipe_dir_object pdo;
+	struct rpc_pipe *pipe;
+	struct rpc_clnt *clnt;
+	const char *name;
+	struct kref kref;
+};
+
 struct gss_auth {
 	struct kref kref;
+	struct hlist_node hash;
 	struct rpc_auth rpc_auth;
 	struct gss_api_mech *mech;
 	enum rpc_gss_svc service;
 	struct rpc_clnt *client;
+	struct net *net;
 	/*
 	 * 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 rpc_pipe *pipe[2];
+	struct gss_pipe *gss_pipe[2];
+	const char *target_name;
 };
 
 /* pipe_version >= 0 if and only if someone has a pipe open. */
 static DEFINE_SPINLOCK(pipe_version_lock);
 static struct rpc_wait_queue pipe_version_rpc_waitqueue;
 static DECLARE_WAIT_QUEUE_HEAD(pipe_version_waitqueue);
+static void gss_put_auth(struct gss_auth *gss_auth);
 
 static void gss_free_ctx(struct gss_cl_ctx *);
 static const struct rpc_pipe_ops gss_upcall_ops_v0;
@@ -124,7 +143,7 @@ gss_cred_set_ctx(struct rpc_cred *cred, struct gss_cl_ctx *ctx)
 	gss_get_ctx(ctx);
 	rcu_assign_pointer(gss_cred->gc_ctx, ctx);
 	set_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
-	smp_mb__before_clear_bit();
+	smp_mb__before_atomic();
 	clear_bit(RPCAUTH_CRED_NEW, &cred->cr_flags);
 }
 
@@ -294,7 +313,7 @@ static void put_pipe_version(struct net *net)
 static void
 gss_release_msg(struct gss_upcall_msg *gss_msg)
 {
-	struct net *net = rpc_net_ns(gss_msg->auth->client);
+	struct net *net = gss_msg->auth->net;
 	if (!atomic_dec_and_test(&gss_msg->count))
 		return;
 	put_pipe_version(net);
@@ -302,6 +321,7 @@ gss_release_msg(struct gss_upcall_msg *gss_msg)
 	if (gss_msg->ctx != NULL)
 		gss_put_ctx(gss_msg->ctx);
 	rpc_destroy_wait_queue(&gss_msg->rpc_waitqueue);
+	gss_put_auth(gss_msg->auth);
 	kfree(gss_msg);
 }
 
@@ -402,91 +422,105 @@ static void gss_encode_v0_msg(struct gss_upcall_msg *gss_msg)
 	memcpy(gss_msg->databuf, &uid, sizeof(uid));
 	gss_msg->msg.data = gss_msg->databuf;
 	gss_msg->msg.len = sizeof(uid);
-	BUG_ON(sizeof(uid) > UPCALL_BUF_LEN);
+
+	BUILD_BUG_ON(sizeof(uid) > sizeof(gss_msg->databuf));
 }
 
-static void gss_encode_v1_msg(struct gss_upcall_msg *gss_msg,
-				struct rpc_clnt *clnt,
-				const char *service_name)
+static int gss_encode_v1_msg(struct gss_upcall_msg *gss_msg,
+				const char *service_name,
+				const char *target_name)
 {
 	struct gss_api_mech *mech = gss_msg->auth->mech;
 	char *p = gss_msg->databuf;
-	int len = 0;
-
-	gss_msg->msg.len = sprintf(gss_msg->databuf, "mech=%s uid=%d ",
-				   mech->gm_name,
-				   from_kuid(&init_user_ns, gss_msg->uid));
-	p += gss_msg->msg.len;
-	if (clnt->cl_principal) {
-		len = sprintf(p, "target=%s ", clnt->cl_principal);
+	size_t buflen = sizeof(gss_msg->databuf);
+	int len;
+
+	len = scnprintf(p, buflen, "mech=%s uid=%d ", mech->gm_name,
+			from_kuid(&init_user_ns, gss_msg->uid));
+	buflen -= len;
+	p += len;
+	gss_msg->msg.len = len;
+	if (target_name) {
+		len = scnprintf(p, buflen, "target=%s ", target_name);
+		buflen -= len;
 		p += len;
 		gss_msg->msg.len += len;
 	}
 	if (service_name != NULL) {
-		len = sprintf(p, "service=%s ", service_name);
+		len = scnprintf(p, buflen, "service=%s ", service_name);
+		buflen -= len;
 		p += len;
 		gss_msg->msg.len += len;
 	}
 	if (mech->gm_upcall_enctypes) {
-		len = sprintf(p, "enctypes=%s ", mech->gm_upcall_enctypes);
+		len = scnprintf(p, buflen, "enctypes=%s ",
+				mech->gm_upcall_enctypes);
+		buflen -= len;
 		p += len;
 		gss_msg->msg.len += len;
 	}
-	len = sprintf(p, "\n");
+	len = scnprintf(p, buflen, "\n");
+	if (len == 0)
+		goto out_overflow;
 	gss_msg->msg.len += len;
 
 	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,
-				struct rpc_clnt *clnt,
-				const char *service_name)
-{
-	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);
+	return 0;
+out_overflow:
+	WARN_ON_ONCE(1);
+	return -ENOMEM;
 }
 
 static struct gss_upcall_msg *
-gss_alloc_msg(struct gss_auth *gss_auth, struct rpc_clnt *clnt,
+gss_alloc_msg(struct gss_auth *gss_auth,
 		kuid_t uid, const char *service_name)
 {
 	struct gss_upcall_msg *gss_msg;
 	int vers;
+	int err = -ENOMEM;
 
 	gss_msg = kzalloc(sizeof(*gss_msg), GFP_NOFS);
 	if (gss_msg == NULL)
-		return ERR_PTR(-ENOMEM);
-	vers = get_pipe_version(rpc_net_ns(clnt));
-	if (vers < 0) {
-		kfree(gss_msg);
-		return ERR_PTR(vers);
-	}
-	gss_msg->pipe = gss_auth->pipe[vers];
+		goto err;
+	vers = get_pipe_version(gss_auth->net);
+	err = vers;
+	if (err < 0)
+		goto err_free_msg;
+	gss_msg->pipe = gss_auth->gss_pipe[vers]->pipe;
 	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->uid = uid;
 	gss_msg->auth = gss_auth;
-	gss_encode_msg(gss_msg, clnt, service_name);
+	switch (vers) {
+	case 0:
+		gss_encode_v0_msg(gss_msg);
+		break;
+	default:
+		err = gss_encode_v1_msg(gss_msg, service_name, gss_auth->target_name);
+		if (err)
+			goto err_put_pipe_version;
+	};
+	kref_get(&gss_auth->kref);
 	return gss_msg;
+err_put_pipe_version:
+	put_pipe_version(gss_auth->net);
+err_free_msg:
+	kfree(gss_msg);
+err:
+	return ERR_PTR(err);
 }
 
 static struct gss_upcall_msg *
-gss_setup_upcall(struct rpc_clnt *clnt, struct gss_auth *gss_auth, struct rpc_cred *cred)
+gss_setup_upcall(struct gss_auth *gss_auth, struct rpc_cred *cred)
 {
 	struct gss_cred *gss_cred = container_of(cred,
 			struct gss_cred, gc_base);
 	struct gss_upcall_msg *gss_new, *gss_msg;
 	kuid_t uid = cred->cr_uid;
 
-	gss_new = gss_alloc_msg(gss_auth, clnt, uid, gss_cred->gc_principal);
+	gss_new = gss_alloc_msg(gss_auth, uid, gss_cred->gc_principal);
 	if (IS_ERR(gss_new))
 		return gss_new;
 	gss_msg = gss_add_msg(gss_new);
@@ -503,14 +537,7 @@ gss_setup_upcall(struct rpc_clnt *clnt, struct gss_auth *gss_auth, struct rpc_cr
 
 static void warn_gssd(void)
 {
-	static unsigned long ratelimit;
-	unsigned long now = jiffies;
-
-	if (time_after(now, ratelimit)) {
-		printk(KERN_WARNING "RPC: AUTH_GSS upcall timed out.\n"
-				"Please check user daemon is running.\n");
-		ratelimit = now + 15*HZ;
-	}
+	dprintk("AUTH_GSS upcall failed. Please check user daemon is running.\n");
 }
 
 static inline int
@@ -527,7 +554,7 @@ gss_refresh_upcall(struct rpc_task *task)
 
 	dprintk("RPC: %5u %s for uid %u\n",
 		task->tk_pid, __func__, from_kuid(&init_user_ns, cred->cr_uid));
-	gss_msg = gss_setup_upcall(task->tk_client, gss_auth, cred);
+	gss_msg = gss_setup_upcall(gss_auth, cred);
 	if (PTR_ERR(gss_msg) == -EAGAIN) {
 		/* XXX: warning on the first, under the assumption we
 		 * shouldn't normally hit this case on a refresh. */
@@ -566,12 +593,11 @@ out:
 static inline int
 gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred)
 {
-	struct net *net = rpc_net_ns(gss_auth->client);
+	struct net *net = gss_auth->net;
 	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 	struct rpc_pipe *pipe;
 	struct rpc_cred *cred = &gss_cred->gc_base;
 	struct gss_upcall_msg *gss_msg;
-	unsigned long timeout;
 	DEFINE_WAIT(wait);
 	int err;
 
@@ -579,17 +605,16 @@ gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred)
 		__func__, from_kuid(&init_user_ns, cred->cr_uid));
 retry:
 	err = 0;
-	/* Default timeout is 15s unless we know that gssd is not running */
-	timeout = 15 * HZ;
-	if (!sn->gssd_running)
-		timeout = HZ >> 2;
-	gss_msg = gss_setup_upcall(gss_auth->client, gss_auth, cred);
+	/* if gssd is down, just skip upcalling altogether */
+	if (!gssd_running(net)) {
+		warn_gssd();
+		return -EACCES;
+	}
+	gss_msg = gss_setup_upcall(gss_auth, cred);
 	if (PTR_ERR(gss_msg) == -EAGAIN) {
 		err = wait_event_interruptible_timeout(pipe_version_waitqueue,
-				sn->pipe_version >= 0, timeout);
+				sn->pipe_version >= 0, 15 * HZ);
 		if (sn->pipe_version < 0) {
-			if (err == 0)
-				sn->gssd_running = 0;
 			warn_gssd();
 			err = -EACCES;
 		}
@@ -797,83 +822,153 @@ gss_pipe_destroy_msg(struct rpc_pipe_msg *msg)
 	}
 }
 
-static void gss_pipes_dentries_destroy(struct rpc_auth *auth)
+static void gss_pipe_dentry_destroy(struct dentry *dir,
+		struct rpc_pipe_dir_object *pdo)
 {
-	struct gss_auth *gss_auth;
+	struct gss_pipe *gss_pipe = pdo->pdo_data;
+	struct rpc_pipe *pipe = gss_pipe->pipe;
 
-	gss_auth = container_of(auth, struct gss_auth, rpc_auth);
-	if (gss_auth->pipe[0]->dentry)
-		rpc_unlink(gss_auth->pipe[0]->dentry);
-	if (gss_auth->pipe[1]->dentry)
-		rpc_unlink(gss_auth->pipe[1]->dentry);
+	if (pipe->dentry != NULL) {
+		rpc_unlink(pipe->dentry);
+		pipe->dentry = NULL;
+	}
 }
 
-static int gss_pipes_dentries_create(struct rpc_auth *auth)
+static int gss_pipe_dentry_create(struct dentry *dir,
+		struct rpc_pipe_dir_object *pdo)
 {
-	int err;
-	struct gss_auth *gss_auth;
-	struct rpc_clnt *clnt;
+	struct gss_pipe *p = pdo->pdo_data;
+	struct dentry *dentry;
 
-	gss_auth = container_of(auth, struct gss_auth, rpc_auth);
-	clnt = gss_auth->client;
-
-	gss_auth->pipe[1]->dentry = rpc_mkpipe_dentry(clnt->cl_dentry,
-						      "gssd",
-						      clnt, gss_auth->pipe[1]);
-	if (IS_ERR(gss_auth->pipe[1]->dentry))
-		return PTR_ERR(gss_auth->pipe[1]->dentry);
-	gss_auth->pipe[0]->dentry = rpc_mkpipe_dentry(clnt->cl_dentry,
-						      gss_auth->mech->gm_name,
-						      clnt, gss_auth->pipe[0]);
-	if (IS_ERR(gss_auth->pipe[0]->dentry)) {
-		err = PTR_ERR(gss_auth->pipe[0]->dentry);
-		goto err_unlink_pipe_1;
-	}
+	dentry = rpc_mkpipe_dentry(dir, p->name, p->clnt, p->pipe);
+	if (IS_ERR(dentry))
+		return PTR_ERR(dentry);
+	p->pipe->dentry = dentry;
 	return 0;
+}
 
-err_unlink_pipe_1:
-	rpc_unlink(gss_auth->pipe[1]->dentry);
-	return err;
+static const struct rpc_pipe_dir_object_ops gss_pipe_dir_object_ops = {
+	.create = gss_pipe_dentry_create,
+	.destroy = gss_pipe_dentry_destroy,
+};
+
+static struct gss_pipe *gss_pipe_alloc(struct rpc_clnt *clnt,
+		const char *name,
+		const struct rpc_pipe_ops *upcall_ops)
+{
+	struct gss_pipe *p;
+	int err = -ENOMEM;
+
+	p = kmalloc(sizeof(*p), GFP_KERNEL);
+	if (p == NULL)
+		goto err;
+	p->pipe = rpc_mkpipe_data(upcall_ops, RPC_PIPE_WAIT_FOR_OPEN);
+	if (IS_ERR(p->pipe)) {
+		err = PTR_ERR(p->pipe);
+		goto err_free_gss_pipe;
+	}
+	p->name = name;
+	p->clnt = clnt;
+	kref_init(&p->kref);
+	rpc_init_pipe_dir_object(&p->pdo,
+			&gss_pipe_dir_object_ops,
+			p);
+	return p;
+err_free_gss_pipe:
+	kfree(p);
+err:
+	return ERR_PTR(err);
+}
+
+struct gss_alloc_pdo {
+	struct rpc_clnt *clnt;
+	const char *name;
+	const struct rpc_pipe_ops *upcall_ops;
+};
+
+static int gss_pipe_match_pdo(struct rpc_pipe_dir_object *pdo, void *data)
+{
+	struct gss_pipe *gss_pipe;
+	struct gss_alloc_pdo *args = data;
+
+	if (pdo->pdo_ops != &gss_pipe_dir_object_ops)
+		return 0;
+	gss_pipe = container_of(pdo, struct gss_pipe, pdo);
+	if (strcmp(gss_pipe->name, args->name) != 0)
+		return 0;
+	if (!kref_get_unless_zero(&gss_pipe->kref))
+		return 0;
+	return 1;
+}
+
+static struct rpc_pipe_dir_object *gss_pipe_alloc_pdo(void *data)
+{
+	struct gss_pipe *gss_pipe;
+	struct gss_alloc_pdo *args = data;
+
+	gss_pipe = gss_pipe_alloc(args->clnt, args->name, args->upcall_ops);
+	if (!IS_ERR(gss_pipe))
+		return &gss_pipe->pdo;
+	return NULL;
 }
 
-static void gss_pipes_dentries_destroy_net(struct rpc_clnt *clnt,
-					   struct rpc_auth *auth)
+static struct gss_pipe *gss_pipe_get(struct rpc_clnt *clnt,
+		const char *name,
+		const struct rpc_pipe_ops *upcall_ops)
 {
 	struct net *net = rpc_net_ns(clnt);
-	struct super_block *sb;
+	struct rpc_pipe_dir_object *pdo;
+	struct gss_alloc_pdo args = {
+		.clnt = clnt,
+		.name = name,
+		.upcall_ops = upcall_ops,
+	};
 
-	sb = rpc_get_sb_net(net);
-	if (sb) {
-		if (clnt->cl_dentry)
-			gss_pipes_dentries_destroy(auth);
-		rpc_put_sb_net(net);
-	}
+	pdo = rpc_find_or_alloc_pipe_dir_object(net,
+			&clnt->cl_pipedir_objects,
+			gss_pipe_match_pdo,
+			gss_pipe_alloc_pdo,
+			&args);
+	if (pdo != NULL)
+		return container_of(pdo, struct gss_pipe, pdo);
+	return ERR_PTR(-ENOMEM);
 }
 
-static int gss_pipes_dentries_create_net(struct rpc_clnt *clnt,
-					 struct rpc_auth *auth)
+static void __gss_pipe_free(struct gss_pipe *p)
 {
+	struct rpc_clnt *clnt = p->clnt;
 	struct net *net = rpc_net_ns(clnt);
-	struct super_block *sb;
-	int err = 0;
 
-	sb = rpc_get_sb_net(net);
-	if (sb) {
-		if (clnt->cl_dentry)
-			err = gss_pipes_dentries_create(auth);
-		rpc_put_sb_net(net);
-	}
-	return err;
+	rpc_remove_pipe_dir_object(net,
+			&clnt->cl_pipedir_objects,
+			&p->pdo);
+	rpc_destroy_pipe_data(p->pipe);
+	kfree(p);
+}
+
+static void __gss_pipe_release(struct kref *kref)
+{
+	struct gss_pipe *p = container_of(kref, struct gss_pipe, kref);
+
+	__gss_pipe_free(p);
+}
+
+static void gss_pipe_free(struct gss_pipe *p)
+{
+	if (p != NULL)
+		kref_put(&p->kref, __gss_pipe_release);
 }
 
 /*
  * NOTE: we have the opportunity to use different
  * parameters based on the input flavor (which must be a pseudoflavor)
  */
-static struct rpc_auth *
-gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
+static struct gss_auth *
+gss_create_new(struct rpc_auth_create_args *args, struct rpc_clnt *clnt)
 {
+	rpc_authflavor_t flavor = args->pseudoflavor;
 	struct gss_auth *gss_auth;
+	struct gss_pipe *gss_pipe;
 	struct rpc_auth * auth;
 	int err = -ENOMEM; /* XXX? */
 
@@ -883,16 +978,26 @@ gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
 		return ERR_PTR(err);
 	if (!(gss_auth = kmalloc(sizeof(*gss_auth), GFP_KERNEL)))
 		goto out_dec;
+	INIT_HLIST_NODE(&gss_auth->hash);
+	gss_auth->target_name = NULL;
+	if (args->target_name) {
+		gss_auth->target_name = kstrdup(args->target_name, GFP_KERNEL);
+		if (gss_auth->target_name == NULL)
+			goto err_free;
+	}
 	gss_auth->client = clnt;
+	gss_auth->net = get_net(rpc_net_ns(clnt));
 	err = -EINVAL;
 	gss_auth->mech = gss_mech_get_by_pseudoflavor(flavor);
 	if (!gss_auth->mech) {
 		dprintk("RPC:       Pseudoflavor %d not found!\n", flavor);
-		goto err_free;
+		goto err_put_net;
 	}
 	gss_auth->service = gss_pseudoflavor_to_service(gss_auth->mech, flavor);
 	if (gss_auth->service == 0)
 		goto err_put_mech;
+	if (!gssd_running(gss_auth->net))
+		goto err_put_mech;
 	auth = &gss_auth->rpc_auth;
 	auth->au_cslack = GSS_CRED_SLACK >> 2;
 	auth->au_rslack = GSS_VERF_SLACK >> 2;
@@ -901,42 +1006,41 @@ gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
 	atomic_set(&auth->au_count, 1);
 	kref_init(&gss_auth->kref);
 
+	err = rpcauth_init_credcache(auth);
+	if (err)
+		goto err_put_mech;
 	/*
 	 * 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->pipe[1] = rpc_mkpipe_data(&gss_upcall_ops_v1,
-					    RPC_PIPE_WAIT_FOR_OPEN);
-	if (IS_ERR(gss_auth->pipe[1])) {
-		err = PTR_ERR(gss_auth->pipe[1]);
-		goto err_put_mech;
+	gss_pipe = gss_pipe_get(clnt, "gssd", &gss_upcall_ops_v1);
+	if (IS_ERR(gss_pipe)) {
+		err = PTR_ERR(gss_pipe);
+		goto err_destroy_credcache;
 	}
+	gss_auth->gss_pipe[1] = gss_pipe;
 
-	gss_auth->pipe[0] = rpc_mkpipe_data(&gss_upcall_ops_v0,
-					    RPC_PIPE_WAIT_FOR_OPEN);
-	if (IS_ERR(gss_auth->pipe[0])) {
-		err = PTR_ERR(gss_auth->pipe[0]);
+	gss_pipe = gss_pipe_get(clnt, gss_auth->mech->gm_name,
+			&gss_upcall_ops_v0);
+	if (IS_ERR(gss_pipe)) {
+		err = PTR_ERR(gss_pipe);
 		goto err_destroy_pipe_1;
 	}
-	err = gss_pipes_dentries_create_net(clnt, auth);
-	if (err)
-		goto err_destroy_pipe_0;
-	err = rpcauth_init_credcache(auth);
-	if (err)
-		goto err_unlink_pipes;
+	gss_auth->gss_pipe[0] = gss_pipe;
 
-	return auth;
-err_unlink_pipes:
-	gss_pipes_dentries_destroy_net(clnt, auth);
-err_destroy_pipe_0:
-	rpc_destroy_pipe_data(gss_auth->pipe[0]);
+	return gss_auth;
 err_destroy_pipe_1:
-	rpc_destroy_pipe_data(gss_auth->pipe[1]);
+	gss_pipe_free(gss_auth->gss_pipe[1]);
+err_destroy_credcache:
+	rpcauth_destroy_credcache(auth);
 err_put_mech:
 	gss_mech_put(gss_auth->mech);
+err_put_net:
+	put_net(gss_auth->net);
 err_free:
+	kfree(gss_auth->target_name);
 	kfree(gss_auth);
 out_dec:
 	module_put(THIS_MODULE);
@@ -946,10 +1050,11 @@ out_dec:
 static void
 gss_free(struct gss_auth *gss_auth)
 {
-	gss_pipes_dentries_destroy_net(gss_auth->client, &gss_auth->rpc_auth);
-	rpc_destroy_pipe_data(gss_auth->pipe[0]);
-	rpc_destroy_pipe_data(gss_auth->pipe[1]);
+	gss_pipe_free(gss_auth->gss_pipe[0]);
+	gss_pipe_free(gss_auth->gss_pipe[1]);
 	gss_mech_put(gss_auth->mech);
+	put_net(gss_auth->net);
+	kfree(gss_auth->target_name);
 
 	kfree(gss_auth);
 	module_put(THIS_MODULE);
@@ -964,17 +1069,118 @@ gss_free_callback(struct kref *kref)
 }
 
 static void
+gss_put_auth(struct gss_auth *gss_auth)
+{
+	kref_put(&gss_auth->kref, gss_free_callback);
+}
+
+static void
 gss_destroy(struct rpc_auth *auth)
 {
-	struct gss_auth *gss_auth;
+	struct gss_auth *gss_auth = container_of(auth,
+			struct gss_auth, rpc_auth);
 
 	dprintk("RPC:       destroying GSS authenticator %p flavor %d\n",
 			auth, auth->au_flavor);
 
+	if (hash_hashed(&gss_auth->hash)) {
+		spin_lock(&gss_auth_hash_lock);
+		hash_del(&gss_auth->hash);
+		spin_unlock(&gss_auth_hash_lock);
+	}
+
+	gss_pipe_free(gss_auth->gss_pipe[0]);
+	gss_auth->gss_pipe[0] = NULL;
+	gss_pipe_free(gss_auth->gss_pipe[1]);
+	gss_auth->gss_pipe[1] = NULL;
 	rpcauth_destroy_credcache(auth);
 
-	gss_auth = container_of(auth, struct gss_auth, rpc_auth);
-	kref_put(&gss_auth->kref, gss_free_callback);
+	gss_put_auth(gss_auth);
+}
+
+/*
+ * Auths may be shared between rpc clients that were cloned from a
+ * common client with the same xprt, if they also share the flavor and
+ * target_name.
+ *
+ * The auth is looked up from the oldest parent sharing the same
+ * cl_xprt, and the auth itself references only that common parent
+ * (which is guaranteed to last as long as any of its descendants).
+ */
+static struct gss_auth *
+gss_auth_find_or_add_hashed(struct rpc_auth_create_args *args,
+		struct rpc_clnt *clnt,
+		struct gss_auth *new)
+{
+	struct gss_auth *gss_auth;
+	unsigned long hashval = (unsigned long)clnt;
+
+	spin_lock(&gss_auth_hash_lock);
+	hash_for_each_possible(gss_auth_hash_table,
+			gss_auth,
+			hash,
+			hashval) {
+		if (gss_auth->client != clnt)
+			continue;
+		if (gss_auth->rpc_auth.au_flavor != args->pseudoflavor)
+			continue;
+		if (gss_auth->target_name != args->target_name) {
+			if (gss_auth->target_name == NULL)
+				continue;
+			if (args->target_name == NULL)
+				continue;
+			if (strcmp(gss_auth->target_name, args->target_name))
+				continue;
+		}
+		if (!atomic_inc_not_zero(&gss_auth->rpc_auth.au_count))
+			continue;
+		goto out;
+	}
+	if (new)
+		hash_add(gss_auth_hash_table, &new->hash, hashval);
+	gss_auth = new;
+out:
+	spin_unlock(&gss_auth_hash_lock);
+	return gss_auth;
+}
+
+static struct gss_auth *
+gss_create_hashed(struct rpc_auth_create_args *args, struct rpc_clnt *clnt)
+{
+	struct gss_auth *gss_auth;
+	struct gss_auth *new;
+
+	gss_auth = gss_auth_find_or_add_hashed(args, clnt, NULL);
+	if (gss_auth != NULL)
+		goto out;
+	new = gss_create_new(args, clnt);
+	if (IS_ERR(new))
+		return new;
+	gss_auth = gss_auth_find_or_add_hashed(args, clnt, new);
+	if (gss_auth != new)
+		gss_destroy(&new->rpc_auth);
+out:
+	return gss_auth;
+}
+
+static struct rpc_auth *
+gss_create(struct rpc_auth_create_args *args, struct rpc_clnt *clnt)
+{
+	struct gss_auth *gss_auth;
+	struct rpc_xprt *xprt = rcu_access_pointer(clnt->cl_xprt);
+
+	while (clnt != clnt->cl_parent) {
+		struct rpc_clnt *parent = clnt->cl_parent;
+		/* Find the original parent for this transport */
+		if (rcu_access_pointer(parent->cl_xprt) != xprt)
+			break;
+		clnt = parent;
+	}
+
+	gss_auth = gss_create_hashed(args, clnt);
+	if (IS_ERR(gss_auth))
+		return ERR_CAST(gss_auth);
+	return &gss_auth->rpc_auth;
 }
 
 /*
@@ -1060,7 +1266,7 @@ gss_destroy_nullcred(struct rpc_cred *cred)
 	call_rcu(&cred->cr_rcu, gss_free_cred_callback);
 	if (ctx)
 		gss_put_ctx(ctx);
-	kref_put(&gss_auth->kref, gss_free_callback);
+	gss_put_auth(gss_auth);
 }
 
 static void
@@ -1126,10 +1332,32 @@ gss_cred_init(struct rpc_auth *auth, struct rpc_cred *cred)
 	return err;
 }
 
+/*
+ * Returns -EACCES if GSS context is NULL or will expire within the
+ * timeout (miliseconds)
+ */
+static int
+gss_key_timeout(struct rpc_cred *rc)
+{
+	struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base);
+	unsigned long now = jiffies;
+	unsigned long expire;
+
+	if (gss_cred->gc_ctx == NULL)
+		return -EACCES;
+
+	expire = gss_cred->gc_ctx->gc_expiry - (gss_key_expire_timeo * HZ);
+
+	if (time_after(now, expire))
+		return -EACCES;
+	return 0;
+}
+
 static int
 gss_match(struct auth_cred *acred, struct rpc_cred *rc, int flags)
 {
 	struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base);
+	int ret;
 
 	if (test_bit(RPCAUTH_CRED_NEW, &rc->cr_flags))
 		goto out;
@@ -1142,11 +1370,26 @@ out:
 	if (acred->principal != NULL) {
 		if (gss_cred->gc_principal == NULL)
 			return 0;
-		return strcmp(acred->principal, gss_cred->gc_principal) == 0;
+		ret = strcmp(acred->principal, gss_cred->gc_principal) == 0;
+		goto check_expire;
 	}
 	if (gss_cred->gc_principal != NULL)
 		return 0;
-	return uid_eq(rc->cr_uid, acred->uid);
+	ret = uid_eq(rc->cr_uid, acred->uid);
+
+check_expire:
+	if (ret == 0)
+		return ret;
+
+	/* Notify acred users of GSS context expiration timeout */
+	if (test_bit(RPC_CRED_NOTIFY_TIMEOUT, &acred->ac_flags) &&
+	    (gss_key_timeout(rc) != 0)) {
+		/* test will now be done from generic cred */
+		test_and_clear_bit(RPC_CRED_NOTIFY_TIMEOUT, &acred->ac_flags);
+		/* tell NFS layer that key will expire soon */
+		set_bit(RPC_CRED_KEY_EXPIRE_SOON, &acred->ac_flags);
+	}
+	return ret;
 }
 
 /*
@@ -1278,7 +1521,7 @@ out:
 static int
 gss_refresh_null(struct rpc_task *task)
 {
-	return -EACCES;
+	return 0;
 }
 
 static __be32 *
@@ -1292,6 +1535,7 @@ gss_validate(struct rpc_task *task, __be32 *p)
 	struct xdr_netobj mic;
 	u32		flav,len;
 	u32		maj_stat;
+	__be32		*ret = ERR_PTR(-EIO);
 
 	dprintk("RPC: %5u %s\n", task->tk_pid, __func__);
 
@@ -1307,6 +1551,7 @@ gss_validate(struct rpc_task *task, __be32 *p)
 	mic.data = (u8 *)p;
 	mic.len = len;
 
+	ret = ERR_PTR(-EACCES);
 	maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &verf_buf, &mic);
 	if (maj_stat == GSS_S_CONTEXT_EXPIRED)
 		clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
@@ -1324,8 +1569,9 @@ gss_validate(struct rpc_task *task, __be32 *p)
 	return p + XDR_QUADLEN(len);
 out_bad:
 	gss_put_ctx(ctx);
-	dprintk("RPC: %5u %s failed.\n", task->tk_pid, __func__);
-	return NULL;
+	dprintk("RPC: %5u %s failed ret %ld.\n", task->tk_pid, __func__,
+		PTR_ERR(ret));
+	return ret;
 }
 
 static void gss_wrap_req_encode(kxdreproc_t encode, struct rpc_rqst *rqstp,
@@ -1657,8 +1903,6 @@ static const struct rpc_authops authgss_ops = {
 	.destroy	= gss_destroy,
 	.lookup_cred	= gss_lookup_cred,
 	.crcreate	= gss_create_cred,
-	.pipes_create	= gss_pipes_dentries_create,
-	.pipes_destroy	= gss_pipes_dentries_destroy,
 	.list_pseudoflavors = gss_mech_list_pseudoflavors,
 	.info2flavor	= gss_mech_info2flavor,
 	.flavor2info	= gss_mech_flavor2info,
@@ -1675,6 +1919,7 @@ static const struct rpc_credops gss_credops = {
 	.crvalidate	= gss_validate,
 	.crwrap_req	= gss_wrap_req,
 	.crunwrap_resp	= gss_unwrap_resp,
+	.crkey_timeout	= gss_key_timeout,
 };
 
 static const struct rpc_credops gss_nullops = {
@@ -1762,5 +2007,12 @@ module_param_named(expired_cred_retry_delay,
 MODULE_PARM_DESC(expired_cred_retry_delay, "Timeout (in seconds) until "
 		"the RPC engine retries an expired credential");
 
+module_param_named(key_expire_timeo,
+		   gss_key_expire_timeo,
+		   uint, 0644);
+MODULE_PARM_DESC(key_expire_timeo, "Time (in seconds) at the end of a "
+		"credential keys lifetime where the NFS layer cleans up "
+		"prior to key expiration");
+
 module_init(init_rpcsec_gss)
 module_exit(exit_rpcsec_gss)
diff --git a/net/sunrpc/auth_gss/gss_krb5_keys.c b/net/sunrpc/auth_gss/gss_krb5_keys.c
index 76e42e6be75..24589bd2a4b 100644
--- a/net/sunrpc/auth_gss/gss_krb5_keys.c
+++ b/net/sunrpc/auth_gss/gss_krb5_keys.c
@@ -59,6 +59,7 @@
 #include <linux/crypto.h>
 #include <linux/sunrpc/gss_krb5.h>
 #include <linux/sunrpc/xdr.h>
+#include <linux/lcm.h>
 
 #ifdef RPC_DEBUG
 # define RPCDBG_FACILITY        RPCDBG_AUTH
@@ -72,7 +73,7 @@
 static void krb5_nfold(u32 inbits, const u8 *in,
 		       u32 outbits, u8 *out)
 {
-	int a, b, c, lcm;
+	unsigned long ulcm;
 	int byte, i, msbit;
 
 	/* the code below is more readable if I make these bytes
@@ -82,17 +83,7 @@ static void krb5_nfold(u32 inbits, const u8 *in,
 	outbits >>= 3;
 
 	/* first compute lcm(n,k) */
-
-	a = outbits;
-	b = inbits;
-
-	while (b != 0) {
-		c = b;
-		b = a%b;
-		a = c;
-	}
-
-	lcm = outbits*inbits/a;
+	ulcm = lcm(inbits, outbits);
 
 	/* now do the real work */
 
@@ -101,7 +92,7 @@ static void krb5_nfold(u32 inbits, const u8 *in,
 
 	/* this will end up cycling through k lcm(k,n)/k times, which
 	   is correct */
-	for (i = lcm-1; i >= 0; i--) {
+	for (i = ulcm-1; i >= 0; i--) {
 		/* compute the msbit in k which gets added into this byte */
 		msbit = (
 			/* first, start with the msbit in the first,
diff --git a/net/sunrpc/auth_gss/gss_krb5_unseal.c b/net/sunrpc/auth_gss/gss_krb5_unseal.c
index 6cd930f3678..6c981ddc19f 100644
--- a/net/sunrpc/auth_gss/gss_krb5_unseal.c
+++ b/net/sunrpc/auth_gss/gss_krb5_unseal.c
@@ -150,7 +150,6 @@ gss_verify_mic_v2(struct krb5_ctx *ctx,
 	struct xdr_netobj cksumobj = {.len = sizeof(cksumdata),
 				      .data = cksumdata};
 	s32 now;
-	u64 seqnum;
 	u8 *ptr = read_token->data;
 	u8 *cksumkey;
 	u8 flags;
@@ -197,9 +196,10 @@ gss_verify_mic_v2(struct krb5_ctx *ctx,
 	if (now > ctx->endtime)
 		return GSS_S_CONTEXT_EXPIRED;
 
-	/* do sequencing checks */
-
-	seqnum = be64_to_cpup((__be64 *)ptr + 8);
+	/*
+	 * NOTE: the sequence number at ptr + 8 is skipped, rpcsec_gss
+	 * doesn't want it checked; see page 6 of rfc 2203.
+	 */
 
 	return GSS_S_COMPLETE;
 }
diff --git a/net/sunrpc/auth_gss/gss_krb5_wrap.c b/net/sunrpc/auth_gss/gss_krb5_wrap.c
index 1da52d1406f..42560e55d97 100644
--- a/net/sunrpc/auth_gss/gss_krb5_wrap.c
+++ b/net/sunrpc/auth_gss/gss_krb5_wrap.c
@@ -489,7 +489,6 @@ static u32
 gss_unwrap_kerberos_v2(struct krb5_ctx *kctx, int offset, struct xdr_buf *buf)
 {
 	s32		now;
-	u64		seqnum;
 	u8		*ptr;
 	u8		flags = 0x00;
 	u16		ec, rrc;
@@ -525,7 +524,10 @@ gss_unwrap_kerberos_v2(struct krb5_ctx *kctx, int offset, struct xdr_buf *buf)
 	ec = be16_to_cpup((__be16 *)(ptr + 4));
 	rrc = be16_to_cpup((__be16 *)(ptr + 6));
 
-	seqnum = be64_to_cpup((__be64 *)(ptr + 8));
+	/*
+	 * NOTE: the sequence number at ptr + 8 is skipped, rpcsec_gss
+	 * doesn't want it checked; see page 6 of rfc 2203.
+	 */
 
 	if (rrc != 0)
 		rotate_left(offset + 16, buf, rrc);
@@ -574,8 +576,8 @@ gss_unwrap_kerberos_v2(struct krb5_ctx *kctx, int offset, struct xdr_buf *buf)
 	buf->head[0].iov_len -= GSS_KRB5_TOK_HDR_LEN + headskip;
 	buf->len -= GSS_KRB5_TOK_HDR_LEN + headskip;
 
-	/* Trim off the checksum blob */
-	xdr_buf_trim(buf, GSS_KRB5_TOK_HDR_LEN + tailskip);
+	/* Trim off the trailing "extra count" and checksum blob */
+	xdr_buf_trim(buf, ec + GSS_KRB5_TOK_HDR_LEN + tailskip);
 	return GSS_S_COMPLETE;
 }
 
diff --git a/net/sunrpc/auth_gss/gss_mech_switch.c b/net/sunrpc/auth_gss/gss_mech_switch.c
index 27ce2624093..92d5ab99fbf 100644
--- a/net/sunrpc/auth_gss/gss_mech_switch.c
+++ b/net/sunrpc/auth_gss/gss_mech_switch.c
@@ -218,10 +218,8 @@ static struct gss_api_mech *_gss_mech_get_by_pseudoflavor(u32 pseudoflavor)
 
 	spin_lock(&registered_mechs_lock);
 	list_for_each_entry(pos, &registered_mechs, gm_list) {
-		if (!mech_supports_pseudoflavor(pos, pseudoflavor)) {
-			module_put(pos->gm_owner);
+		if (!mech_supports_pseudoflavor(pos, pseudoflavor))
 			continue;
-		}
 		if (try_module_get(pos->gm_owner))
 			gm = pos;
 		break;
diff --git a/net/sunrpc/auth_gss/gss_rpc_upcall.c b/net/sunrpc/auth_gss/gss_rpc_upcall.c
index af7ffd447fe..abbb7dcd168 100644
--- a/net/sunrpc/auth_gss/gss_rpc_upcall.c
+++ b/net/sunrpc/auth_gss/gss_rpc_upcall.c
@@ -137,7 +137,6 @@ void init_gssp_clnt(struct sunrpc_net *sn)
 {
 	mutex_init(&sn->gssp_lock);
 	sn->gssp_clnt = NULL;
-	init_waitqueue_head(&sn->gssp_wq);
 }
 
 int set_gssp_clnt(struct net *net)
@@ -154,7 +153,6 @@ int set_gssp_clnt(struct net *net)
 		sn->gssp_clnt = clnt;
 	}
 	mutex_unlock(&sn->gssp_lock);
-	wake_up(&sn->gssp_wq);
 	return ret;
 }
 
@@ -213,6 +211,26 @@ static int gssp_call(struct net *net, struct rpc_message *msg)
 	return status;
 }
 
+static void gssp_free_receive_pages(struct gssx_arg_accept_sec_context *arg)
+{
+	int i;
+
+	for (i = 0; i < arg->npages && arg->pages[i]; i++)
+		__free_page(arg->pages[i]);
+}
+
+static int gssp_alloc_receive_pages(struct gssx_arg_accept_sec_context *arg)
+{
+	arg->npages = DIV_ROUND_UP(NGROUPS_MAX * 4, PAGE_SIZE);
+	arg->pages = kzalloc(arg->npages * sizeof(struct page *), GFP_KERNEL);
+	/*
+	 * XXX: actual pages are allocated by xdr layer in
+	 * xdr_partial_copy_from_skb.
+	 */
+	if (!arg->pages)
+		return -ENOMEM;
+	return 0;
+}
 
 /*
  * Public functions
@@ -261,10 +279,16 @@ int gssp_accept_sec_context_upcall(struct net *net,
 		arg.context_handle = &ctxh;
 	res.output_token->len = GSSX_max_output_token_sz;
 
+	ret = gssp_alloc_receive_pages(&arg);
+	if (ret)
+		return ret;
+
 	/* use nfs/ for targ_name ? */
 
 	ret = gssp_call(net, &msg);
 
+	gssp_free_receive_pages(&arg);
+
 	/* we need to fetch all data even in case of error so
 	 * that we can free special strctures is they have been allocated */
 	data->major_status = res.status.major_status;
@@ -272,7 +296,8 @@ int gssp_accept_sec_context_upcall(struct net *net,
 	if (res.context_handle) {
 		data->out_handle = rctxh.exported_context_token;
 		data->mech_oid.len = rctxh.mech.len;
-		memcpy(data->mech_oid.data, rctxh.mech.data,
+		if (rctxh.mech.data)
+			memcpy(data->mech_oid.data, rctxh.mech.data,
 						data->mech_oid.len);
 		client_name = rctxh.src_name.display_name;
 	}
diff --git a/net/sunrpc/auth_gss/gss_rpc_xdr.c b/net/sunrpc/auth_gss/gss_rpc_xdr.c
index 3c85d1c8a02..1ec19f6f0c2 100644
--- a/net/sunrpc/auth_gss/gss_rpc_xdr.c
+++ b/net/sunrpc/auth_gss/gss_rpc_xdr.c
@@ -166,14 +166,15 @@ static int dummy_dec_opt_array(struct xdr_stream *xdr,
 	return 0;
 }
 
-static int get_s32(void **p, void *max, s32 *res)
+static int get_host_u32(struct xdr_stream *xdr, u32 *res)
 {
-	void *base = *p;
-	void *next = (void *)((char *)base + sizeof(s32));
-	if (unlikely(next > max || next < base))
+	__be32 *p;
+
+	p = xdr_inline_decode(xdr, 4);
+	if (!p)
 		return -EINVAL;
-	memcpy(res, base, sizeof(s32));
-	*p = next;
+	/* Contents of linux creds are all host-endian: */
+	memcpy(res, p, sizeof(u32));
 	return 0;
 }
 
@@ -182,9 +183,9 @@ static int gssx_dec_linux_creds(struct xdr_stream *xdr,
 {
 	u32 length;
 	__be32 *p;
-	void *q, *end;
-	s32 tmp;
-	int N, i, err;
+	u32 tmp;
+	u32 N;
+	int i, err;
 
 	p = xdr_inline_decode(xdr, 4);
 	if (unlikely(p == NULL))
@@ -192,33 +193,28 @@ static int gssx_dec_linux_creds(struct xdr_stream *xdr,
 
 	length = be32_to_cpup(p);
 
-	/* FIXME: we do not want to use the scratch buffer for this one
-	 * may need to use functions that allows us to access an io vector
-	 * directly */
-	p = xdr_inline_decode(xdr, length);
-	if (unlikely(p == NULL))
+	if (length > (3 + NGROUPS_MAX) * sizeof(u32))
 		return -ENOSPC;
 
-	q = p;
-	end = q + length;
-
 	/* uid */
-	err = get_s32(&q, end, &tmp);
+	err = get_host_u32(xdr, &tmp);
 	if (err)
 		return err;
 	creds->cr_uid = make_kuid(&init_user_ns, tmp);
 
 	/* gid */
-	err = get_s32(&q, end, &tmp);
+	err = get_host_u32(xdr, &tmp);
 	if (err)
 		return err;
 	creds->cr_gid = make_kgid(&init_user_ns, tmp);
 
 	/* number of additional gid's */
-	err = get_s32(&q, end, &tmp);
+	err = get_host_u32(xdr, &tmp);
 	if (err)
 		return err;
 	N = tmp;
+	if ((3 + N) * sizeof(u32) != length)
+		return -EINVAL;
 	creds->cr_group_info = groups_alloc(N);
 	if (creds->cr_group_info == NULL)
 		return -ENOMEM;
@@ -226,7 +222,7 @@ static int gssx_dec_linux_creds(struct xdr_stream *xdr,
 	/* gid's */
 	for (i = 0; i < N; i++) {
 		kgid_t kgid;
-		err = get_s32(&q, end, &tmp);
+		err = get_host_u32(xdr, &tmp);
 		if (err)
 			goto out_free_groups;
 		err = -EINVAL;
@@ -563,6 +559,8 @@ static int gssx_enc_cred(struct xdr_stream *xdr,
 
 	/* cred->elements */
 	err = dummy_enc_credel_array(xdr, &cred->elements);
+	if (err)
+		return err;
 
 	/* cred->cred_handle_reference */
 	err = gssx_enc_buffer(xdr, &cred->cred_handle_reference);
@@ -744,22 +742,20 @@ void gssx_enc_accept_sec_context(struct rpc_rqst *req,
 		goto done;
 
 	/* arg->context_handle */
-	if (arg->context_handle) {
+	if (arg->context_handle)
 		err = gssx_enc_ctx(xdr, arg->context_handle);
-		if (err)
-			goto done;
-	} else {
+	else
 		err = gssx_enc_bool(xdr, 0);
-	}
+	if (err)
+		goto done;
 
 	/* arg->cred_handle */
-	if (arg->cred_handle) {
+	if (arg->cred_handle)
 		err = gssx_enc_cred(xdr, arg->cred_handle);
-		if (err)
-			goto done;
-	} else {
+	else
 		err = gssx_enc_bool(xdr, 0);
-	}
+	if (err)
+		goto done;
 
 	/* arg->input_token */
 	err = gssx_enc_in_token(xdr, &arg->input_token);
@@ -767,13 +763,12 @@ void gssx_enc_accept_sec_context(struct rpc_rqst *req,
 		goto done;
 
 	/* arg->input_cb */
-	if (arg->input_cb) {
+	if (arg->input_cb)
 		err = gssx_enc_cb(xdr, arg->input_cb);
-		if (err)
-			goto done;
-	} else {
+	else
 		err = gssx_enc_bool(xdr, 0);
-	}
+	if (err)
+		goto done;
 
 	err = gssx_enc_bool(xdr, arg->ret_deleg_cred);
 	if (err)
@@ -784,6 +779,9 @@ void gssx_enc_accept_sec_context(struct rpc_rqst *req,
 	/* arg->options */
 	err = dummy_enc_opt_array(xdr, &arg->options);
 
+	xdr_inline_pages(&req->rq_rcv_buf,
+		PAGE_SIZE/2 /* pretty arbitrary */,
+		arg->pages, 0 /* page base */, arg->npages * PAGE_SIZE);
 done:
 	if (err)
 		dprintk("RPC:       gssx_enc_accept_sec_context: %d\n", err);
diff --git a/net/sunrpc/auth_gss/gss_rpc_xdr.h b/net/sunrpc/auth_gss/gss_rpc_xdr.h
index 1c98b27d870..685a688f3d8 100644
--- a/net/sunrpc/auth_gss/gss_rpc_xdr.h
+++ b/net/sunrpc/auth_gss/gss_rpc_xdr.h
@@ -147,6 +147,8 @@ struct gssx_arg_accept_sec_context {
 	struct gssx_cb *input_cb;
 	u32 ret_deleg_cred;
 	struct gssx_option_array options;
+	struct page **pages;
+	unsigned int npages;
 };
 
 struct gssx_res_accept_sec_context {
@@ -240,7 +242,8 @@ int gssx_dec_accept_sec_context(struct rpc_rqst *rqstp,
 			     2 * GSSX_max_princ_sz + \
 			     8 + 8 + 4 + 4 + 4)
 #define GSSX_max_output_token_sz 1024
-#define GSSX_max_creds_sz (4 + 4 + 4 + NGROUPS_MAX * 4)
+/* grouplist not included; we allocate separate pages for that: */
+#define GSSX_max_creds_sz (4 + 4 + 4 /* + NGROUPS_MAX*4 */)
 #define GSSX_RES_accept_sec_context_sz (GSSX_default_status_sz + \
 					GSSX_default_ctx_sz + \
 					GSSX_max_output_token_sz + \
diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c
index 09fb638bcaa..4ce5eccec1f 100644
--- a/net/sunrpc/auth_gss/svcauth_gss.c
+++ b/net/sunrpc/auth_gss/svcauth_gss.c
@@ -1167,8 +1167,8 @@ static int gss_proxy_save_rsc(struct cache_detail *cd,
 	if (!ud->found_creds) {
 		/* userspace seem buggy, we should always get at least a
 		 * mapping to nobody */
-		dprintk("RPC:       No creds found, marking Negative!\n");
-		set_bit(CACHE_NEGATIVE, &rsci.h.flags);
+		dprintk("RPC:       No creds found!\n");
+		goto out;
 	} else {
 
 		/* steal creds */
@@ -1263,65 +1263,34 @@ out:
 	return ret;
 }
 
-DEFINE_SPINLOCK(use_gssp_lock);
-
-static bool use_gss_proxy(struct net *net)
-{
-	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
-
-	if (sn->use_gss_proxy != -1)
-		return sn->use_gss_proxy;
-	spin_lock(&use_gssp_lock);
-	/*
-	 * If you wanted gss-proxy, you should have said so before
-	 * starting to accept requests:
-	 */
-	sn->use_gss_proxy = 0;
-	spin_unlock(&use_gssp_lock);
-	return 0;
-}
-
-#ifdef CONFIG_PROC_FS
-
+/*
+ * Try to set the sn->use_gss_proxy variable to a new value. We only allow
+ * it to be changed if it's currently undefined (-1). If it's any other value
+ * then return -EBUSY unless the type wouldn't have changed anyway.
+ */
 static int set_gss_proxy(struct net *net, int type)
 {
 	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
-	int ret = 0;
+	int ret;
 
 	WARN_ON_ONCE(type != 0 && type != 1);
-	spin_lock(&use_gssp_lock);
-	if (sn->use_gss_proxy == -1 || sn->use_gss_proxy == type)
-		sn->use_gss_proxy = type;
-	else
-		ret = -EBUSY;
-	spin_unlock(&use_gssp_lock);
-	wake_up(&sn->gssp_wq);
-	return ret;
-}
-
-static inline bool gssp_ready(struct sunrpc_net *sn)
-{
-	switch (sn->use_gss_proxy) {
-		case -1:
-			return false;
-		case 0:
-			return true;
-		case 1:
-			return sn->gssp_clnt;
-	}
-	WARN_ON_ONCE(1);
-	return false;
+	ret = cmpxchg(&sn->use_gss_proxy, -1, type);
+	if (ret != -1 && ret != type)
+		return -EBUSY;
+	return 0;
 }
 
-static int wait_for_gss_proxy(struct net *net, struct file *file)
+static bool use_gss_proxy(struct net *net)
 {
 	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 
-	if (file->f_flags & O_NONBLOCK && !gssp_ready(sn))
-		return -EAGAIN;
-	return wait_event_interruptible(sn->gssp_wq, gssp_ready(sn));
+	/* If use_gss_proxy is still undefined, then try to disable it */
+	if (sn->use_gss_proxy == -1)
+		set_gss_proxy(net, 0);
+	return sn->use_gss_proxy;
 }
 
+#ifdef CONFIG_PROC_FS
 
 static ssize_t write_gssp(struct file *file, const char __user *buf,
 			 size_t count, loff_t *ppos)
@@ -1342,10 +1311,10 @@ static ssize_t write_gssp(struct file *file, const char __user *buf,
 		return res;
 	if (i != 1)
 		return -EINVAL;
-	res = set_gss_proxy(net, 1);
+	res = set_gssp_clnt(net);
 	if (res)
 		return res;
-	res = set_gssp_clnt(net);
+	res = set_gss_proxy(net, 1);
 	if (res)
 		return res;
 	return count;
@@ -1355,16 +1324,12 @@ static ssize_t read_gssp(struct file *file, char __user *buf,
 			 size_t count, loff_t *ppos)
 {
 	struct net *net = PDE_DATA(file_inode(file));
+	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 	unsigned long p = *ppos;
 	char tbuf[10];
 	size_t len;
-	int ret;
 
-	ret = wait_for_gss_proxy(net, file);
-	if (ret)
-		return ret;
-
-	snprintf(tbuf, sizeof(tbuf), "%d\n", use_gss_proxy(net));
+	snprintf(tbuf, sizeof(tbuf), "%d\n", sn->use_gss_proxy);
 	len = strlen(tbuf);
 	if (p >= len)
 		return 0;
@@ -1538,6 +1503,7 @@ svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
 			if (unwrap_integ_data(rqstp, &rqstp->rq_arg,
 					gc->gc_seq, rsci->mechctx))
 				goto garbage_args;
+			rqstp->rq_auth_slack = RPC_MAX_AUTH_SIZE;
 			break;
 		case RPC_GSS_SVC_PRIVACY:
 			/* placeholders for length and seq. number: */
@@ -1546,6 +1512,7 @@ svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
 			if (unwrap_priv_data(rqstp, &rqstp->rq_arg,
 					gc->gc_seq, rsci->mechctx))
 				goto garbage_args;
+			rqstp->rq_auth_slack = RPC_MAX_AUTH_SIZE * 2;
 			break;
 		default:
 			goto auth_err;
@@ -1626,8 +1593,7 @@ svcauth_gss_wrap_resp_integ(struct svc_rqst *rqstp)
 	BUG_ON(integ_len % 4);
 	*p++ = htonl(integ_len);
 	*p++ = htonl(gc->gc_seq);
-	if (xdr_buf_subsegment(resbuf, &integ_buf, integ_offset,
-				integ_len))
+	if (xdr_buf_subsegment(resbuf, &integ_buf, integ_offset, integ_len))
 		BUG();
 	if (resbuf->tail[0].iov_base == NULL) {
 		if (resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE > PAGE_SIZE)
@@ -1635,10 +1601,8 @@ svcauth_gss_wrap_resp_integ(struct svc_rqst *rqstp)
 		resbuf->tail[0].iov_base = resbuf->head[0].iov_base
 						+ resbuf->head[0].iov_len;
 		resbuf->tail[0].iov_len = 0;
-		resv = &resbuf->tail[0];
-	} else {
-		resv = &resbuf->tail[0];
 	}
+	resv = &resbuf->tail[0];
 	mic.data = (u8 *)resv->iov_base + resv->iov_len + 4;
 	if (gss_get_mic(gsd->rsci->mechctx, &integ_buf, &mic))
 		goto out_err;