xnu-792.12.6.tar.gz

[apple/xnu.git] / osfmk / ipc / ipc_kmsg.c

diff --git a/osfmk/ipc/ipc_kmsg.c b/osfmk/ipc/ipc_kmsg.c
index 2edc405596e4eb3551388f95fb03eb75977a4e52..c122d9bc0dd7e6cdb794967dc2491b7415296f19 100644 (file)
--- a/osfmk/ipc/ipc_kmsg.c
+++ b/osfmk/ipc/ipc_kmsg.c
@@ -1,23 +1,31 @@
 /*
  * Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved.
  *
- * @APPLE_LICENSE_HEADER_START@
+ * @APPLE_LICENSE_OSREFERENCE_HEADER_START@
  * 
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License").  You may not use this file except in compliance with the
- * License.  Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
- * 
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
- * License for the specific language governing rights and limitations
- * under the License.
- * 
- * @APPLE_LICENSE_HEADER_END@
+ * This file contains Original Code and/or Modifications of Original Code 
+ * as defined in and that are subject to the Apple Public Source License 
+ * Version 2.0 (the 'License'). You may not use this file except in 
+ * compliance with the License.  The rights granted to you under the 
+ * License may not be used to create, or enable the creation or 
+ * redistribution of, unlawful or unlicensed copies of an Apple operating 
+ * system, or to circumvent, violate, or enable the circumvention or 
+ * violation of, any terms of an Apple operating system software license 
+ * agreement.
+ *
+ * Please obtain a copy of the License at 
+ * http://www.opensource.apple.com/apsl/ and read it before using this 
+ * file.
+ *
+ * The Original Code and all software distributed under the License are 
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 
+ * Please see the License for the specific language governing rights and 
+ * limitations under the License.
+ *
+ * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  */
 /*
  * @OSF_COPYRIGHT@
@@ -200,8 +208,6 @@ ipc_kmsg_alloc(
        ipc_kmsg_t kmsg;
 
 #if !defined(__LP64__)
-       mach_msg_size_t size = msg_and_trailer_size - MAX_TRAILER_SIZE;
-
        /*
         * LP64support -
         * Pad the allocation in case we need to expand the
@@ -215,20 +221,23 @@ ipc_kmsg_alloc(
         * forward as we process them than it is to push all the
         * data backwards.
         */
-       max_expanded_size = 
-               (size > sizeof(mach_msg_base_t)) ?
-               (msg_and_trailer_size + DESC_SIZE_ADJUSTMENT * 
-                ((size - sizeof(mach_msg_base_t)) /
-                 (sizeof(mach_msg_ool_descriptor_t))))
-               :
-               (msg_and_trailer_size);
-#else
-       max_expanded_size = msg_and_trailer_size;
+
+       mach_msg_size_t size = msg_and_trailer_size - MAX_TRAILER_SIZE;
+       if (size > sizeof(mach_msg_base_t)) {
+               mach_msg_size_t max_desc = ((size - sizeof(mach_msg_base_t)) /
+                                          sizeof(mach_msg_ool_descriptor_t)) *
+                                          DESC_SIZE_ADJUSTMENT;
+               if (msg_and_trailer_size >= MACH_MSG_SIZE_MAX - max_desc)
+                       return IKM_NULL;
+               max_expanded_size = msg_and_trailer_size + max_desc;
+       } else
 #endif
+               max_expanded_size = msg_and_trailer_size;
 
-       /* round up for ikm_cache */
-       if (max_expanded_size < IKM_SAVED_MSG_SIZE)
-               max_expanded_size = IKM_SAVED_MSG_SIZE;
+       if (max_expanded_size > ikm_less_overhead(MACH_MSG_SIZE_MAX))
+               return IKM_NULL;
+       else if (max_expanded_size < IKM_SAVED_MSG_SIZE)
+               max_expanded_size = IKM_SAVED_MSG_SIZE;         /* round up for ikm_cache */
 
        if (max_expanded_size == IKM_SAVED_MSG_SIZE) {
                struct ikm_cache        *cache;
@@ -712,6 +721,9 @@ ipc_kmsg_get(
        if ((size < sizeof(mach_msg_header_t)) || (size & 3))
                return MACH_SEND_MSG_TOO_SMALL;
 
+       if (size > MACH_MSG_SIZE_MAX - MAX_TRAILER_SIZE)
+               return MACH_SEND_TOO_LARGE;
+
        msg_and_trailer_size = size + MAX_TRAILER_SIZE;
 
        kmsg = ipc_kmsg_alloc(msg_and_trailer_size);