A malicious monitor can craft an auth reply message that could cause a NULL function pointer dereference in the client's kernel. To prevent this, the auth_none protocol handler needs an empty ceph_auth_client_ops->build_request() function. CVE-2013-1059 Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Reported-by: Chanam Park <chanam.park@hkpco.kr> Reviewed-by: Seth Arnold <seth.arnold@canonical.com> Reviewed-by: Sage Weil <sage@inktank.com> Cc: stable@vger.kernel.org
		
			
				
	
	
		
			137 lines
		
	
	
	
		
			3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			137 lines
		
	
	
	
		
			3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
 | 
						|
#include <linux/ceph/ceph_debug.h>
 | 
						|
 | 
						|
#include <linux/err.h>
 | 
						|
#include <linux/module.h>
 | 
						|
#include <linux/random.h>
 | 
						|
#include <linux/slab.h>
 | 
						|
 | 
						|
#include <linux/ceph/decode.h>
 | 
						|
#include <linux/ceph/auth.h>
 | 
						|
 | 
						|
#include "auth_none.h"
 | 
						|
 | 
						|
static void reset(struct ceph_auth_client *ac)
 | 
						|
{
 | 
						|
	struct ceph_auth_none_info *xi = ac->private;
 | 
						|
 | 
						|
	xi->starting = true;
 | 
						|
	xi->built_authorizer = false;
 | 
						|
}
 | 
						|
 | 
						|
static void destroy(struct ceph_auth_client *ac)
 | 
						|
{
 | 
						|
	kfree(ac->private);
 | 
						|
	ac->private = NULL;
 | 
						|
}
 | 
						|
 | 
						|
static int is_authenticated(struct ceph_auth_client *ac)
 | 
						|
{
 | 
						|
	struct ceph_auth_none_info *xi = ac->private;
 | 
						|
 | 
						|
	return !xi->starting;
 | 
						|
}
 | 
						|
 | 
						|
static int should_authenticate(struct ceph_auth_client *ac)
 | 
						|
{
 | 
						|
	struct ceph_auth_none_info *xi = ac->private;
 | 
						|
 | 
						|
	return xi->starting;
 | 
						|
}
 | 
						|
 | 
						|
static int build_request(struct ceph_auth_client *ac, void *buf, void *end)
 | 
						|
{
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 * the generic auth code decode the global_id, and we carry no actual
 | 
						|
 * authenticate state, so nothing happens here.
 | 
						|
 */
 | 
						|
static int handle_reply(struct ceph_auth_client *ac, int result,
 | 
						|
			void *buf, void *end)
 | 
						|
{
 | 
						|
	struct ceph_auth_none_info *xi = ac->private;
 | 
						|
 | 
						|
	xi->starting = false;
 | 
						|
	return result;
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 * build an 'authorizer' with our entity_name and global_id.  we can
 | 
						|
 * reuse a single static copy since it is identical for all services
 | 
						|
 * we connect to.
 | 
						|
 */
 | 
						|
static int ceph_auth_none_create_authorizer(
 | 
						|
	struct ceph_auth_client *ac, int peer_type,
 | 
						|
	struct ceph_auth_handshake *auth)
 | 
						|
{
 | 
						|
	struct ceph_auth_none_info *ai = ac->private;
 | 
						|
	struct ceph_none_authorizer *au = &ai->au;
 | 
						|
	void *p, *end;
 | 
						|
	int ret;
 | 
						|
 | 
						|
	if (!ai->built_authorizer) {
 | 
						|
		p = au->buf;
 | 
						|
		end = p + sizeof(au->buf);
 | 
						|
		ceph_encode_8(&p, 1);
 | 
						|
		ret = ceph_entity_name_encode(ac->name, &p, end - 8);
 | 
						|
		if (ret < 0)
 | 
						|
			goto bad;
 | 
						|
		ceph_decode_need(&p, end, sizeof(u64), bad2);
 | 
						|
		ceph_encode_64(&p, ac->global_id);
 | 
						|
		au->buf_len = p - (void *)au->buf;
 | 
						|
		ai->built_authorizer = true;
 | 
						|
		dout("built authorizer len %d\n", au->buf_len);
 | 
						|
	}
 | 
						|
 | 
						|
	auth->authorizer = (struct ceph_authorizer *) au;
 | 
						|
	auth->authorizer_buf = au->buf;
 | 
						|
	auth->authorizer_buf_len = au->buf_len;
 | 
						|
	auth->authorizer_reply_buf = au->reply_buf;
 | 
						|
	auth->authorizer_reply_buf_len = sizeof (au->reply_buf);
 | 
						|
 | 
						|
	return 0;
 | 
						|
 | 
						|
bad2:
 | 
						|
	ret = -ERANGE;
 | 
						|
bad:
 | 
						|
	return ret;
 | 
						|
}
 | 
						|
 | 
						|
static void ceph_auth_none_destroy_authorizer(struct ceph_auth_client *ac,
 | 
						|
				      struct ceph_authorizer *a)
 | 
						|
{
 | 
						|
	/* nothing to do */
 | 
						|
}
 | 
						|
 | 
						|
static const struct ceph_auth_client_ops ceph_auth_none_ops = {
 | 
						|
	.name = "none",
 | 
						|
	.reset = reset,
 | 
						|
	.destroy = destroy,
 | 
						|
	.is_authenticated = is_authenticated,
 | 
						|
	.should_authenticate = should_authenticate,
 | 
						|
	.build_request = build_request,
 | 
						|
	.handle_reply = handle_reply,
 | 
						|
	.create_authorizer = ceph_auth_none_create_authorizer,
 | 
						|
	.destroy_authorizer = ceph_auth_none_destroy_authorizer,
 | 
						|
};
 | 
						|
 | 
						|
int ceph_auth_none_init(struct ceph_auth_client *ac)
 | 
						|
{
 | 
						|
	struct ceph_auth_none_info *xi;
 | 
						|
 | 
						|
	dout("ceph_auth_none_init %p\n", ac);
 | 
						|
	xi = kzalloc(sizeof(*xi), GFP_NOFS);
 | 
						|
	if (!xi)
 | 
						|
		return -ENOMEM;
 | 
						|
 | 
						|
	xi->starting = true;
 | 
						|
	xi->built_authorizer = false;
 | 
						|
 | 
						|
	ac->protocol = CEPH_AUTH_NONE;
 | 
						|
	ac->private = xi;
 | 
						|
	ac->ops = &ceph_auth_none_ops;
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 |