Commit ac83228a authored by Trond Myklebust's avatar Trond Myklebust Committed by Anna Schumaker
Browse files

SUNRPC: Use namespace of listening daemon in the client AUTH_GSS upcall 



When the client needs to talk to rpc.gssd, we should ensure that the
uid argument is encoded to match the user namespace of the daemon.

Signed-off-by: default avatarTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: default avatarAnna Schumaker <Anna.Schumaker@Netapp.com>
parent 283ebe3e

net/sunrpc/auth_gss/auth_gss.c

+44 −16
Original line number Diff line number Diff line
@@ -269,6 +269,7 @@ gss_fill_context(const void *p, const void *end, struct gss_cl_ctx *ctx, struct 
struct gss_upcall_msg {

	refcount_t count;

	kuid_t	uid;

	const char *service_name;

	struct rpc_pipe_msg msg;

	struct list_head list;

	struct gss_auth *auth;
@@ -316,6 +317,7 @@ gss_release_msg(struct gss_upcall_msg *gss_msg) 
		gss_put_ctx(gss_msg->ctx);

	rpc_destroy_wait_queue(&gss_msg->rpc_waitqueue);

	gss_put_auth(gss_msg->auth);

	kfree_const(gss_msg->service_name);

	kfree(gss_msg);

}
@@ -410,10 +412,10 @@ gss_upcall_callback(struct rpc_task *task) 
	gss_release_msg(gss_msg);

}



static void gss_encode_v0_msg(struct gss_upcall_msg *gss_msg)

static void gss_encode_v0_msg(struct gss_upcall_msg *gss_msg,

			      const struct cred *cred)

{

	struct user_namespace *userns = gss_msg->auth->client->cl_cred ?

		gss_msg->auth->client->cl_cred->user_ns : &init_user_ns;

	struct user_namespace *userns = cred->user_ns;



	uid_t uid = from_kuid_munged(userns, gss_msg->uid);

	memcpy(gss_msg->databuf, &uid, sizeof(uid));
@@ -423,12 +425,24 @@ static void gss_encode_v0_msg(struct gss_upcall_msg *gss_msg) 
	BUILD_BUG_ON(sizeof(uid) > sizeof(gss_msg->databuf));

}



static ssize_t

gss_v0_upcall(struct file *file, struct rpc_pipe_msg *msg,

		char __user *buf, size_t buflen)

{

	struct gss_upcall_msg *gss_msg = container_of(msg,

						      struct gss_upcall_msg,

						      msg);

	if (msg->copied == 0)

		gss_encode_v0_msg(gss_msg, file->f_cred);

	return rpc_pipe_generic_upcall(file, msg, buf, buflen);

}



static int gss_encode_v1_msg(struct gss_upcall_msg *gss_msg,

				const char *service_name,

				const char *target_name)

				const char *target_name,

				const struct cred *cred)

{

	struct user_namespace *userns = gss_msg->auth->client->cl_cred ?

		gss_msg->auth->client->cl_cred->user_ns : &init_user_ns;

	struct user_namespace *userns = cred->user_ns;

	struct gss_api_mech *mech = gss_msg->auth->mech;

	char *p = gss_msg->databuf;

	size_t buflen = sizeof(gss_msg->databuf);
@@ -496,6 +510,25 @@ static int gss_encode_v1_msg(struct gss_upcall_msg *gss_msg, 
	return -ENOMEM;

}



static ssize_t

gss_v1_upcall(struct file *file, struct rpc_pipe_msg *msg,

		char __user *buf, size_t buflen)

{

	struct gss_upcall_msg *gss_msg = container_of(msg,

						      struct gss_upcall_msg,

						      msg);

	int err;

	if (msg->copied == 0) {

		err = gss_encode_v1_msg(gss_msg,

					gss_msg->service_name,

					gss_msg->auth->target_name,

					file->f_cred);

		if (err)

			return err;

	}

	return rpc_pipe_generic_upcall(file, msg, buf, buflen);

}



static struct gss_upcall_msg *

gss_alloc_msg(struct gss_auth *gss_auth,

		kuid_t uid, const char *service_name)
@@ -518,16 +551,11 @@ gss_alloc_msg(struct gss_auth *gss_auth, 
	refcount_set(&gss_msg->count, 1);

	gss_msg->uid = uid;

	gss_msg->auth = gss_auth;

	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)

	if (service_name) {

		gss_msg->service_name = kstrdup_const(service_name, GFP_NOFS);

		if (!gss_msg->service_name)

			goto err_put_pipe_version;

	}

	kref_get(&gss_auth->kref);

	return gss_msg;

err_put_pipe_version:

	put_pipe_version(gss_auth->net);
@@ -2120,7 +2148,7 @@ static const struct rpc_credops gss_nullops = { 
};



static const struct rpc_pipe_ops gss_upcall_ops_v0 = {

	.upcall		= rpc_pipe_generic_upcall,

	.upcall		= gss_v0_upcall,

	.downcall	= gss_pipe_downcall,

	.destroy_msg	= gss_pipe_destroy_msg,

	.open_pipe	= gss_pipe_open_v0,
@@ -2128,7 +2156,7 @@ static const struct rpc_pipe_ops gss_upcall_ops_v0 = { 
};



static const struct rpc_pipe_ops gss_upcall_ops_v1 = {

	.upcall		= rpc_pipe_generic_upcall,

	.upcall		= gss_v1_upcall,

	.downcall	= gss_pipe_downcall,

	.destroy_msg	= gss_pipe_destroy_msg,

	.open_pipe	= gss_pipe_open_v1,