xref: /freebsd/sys/amd64/include/asan.h (revision e8d8bef961a50d4dc22501cde4fb9fb0be1b2532)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2020 The FreeBSD Foundation
5  *
6  * This software was developed by Mark Johnston under sponsorship from the
7  * FreeBSD Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions are
11  * met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in
16  *    the documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #ifndef _MACHINE_ASAN_H_
32 #define	_MACHINE_ASAN_H_
33 
34 #ifdef KASAN
35 
36 #include <vm/vm.h>
37 #include <vm/pmap.h>
38 #include <vm/vm_page.h>
39 #include <machine/vmparam.h>
40 
41 static inline vm_offset_t
42 kasan_md_addr_to_shad(vm_offset_t addr)
43 {
44 	return (((addr - VM_MIN_KERNEL_ADDRESS) >> KASAN_SHADOW_SCALE_SHIFT) +
45 	    KASAN_MIN_ADDRESS);
46 }
47 
48 static inline bool
49 kasan_md_unsupported(vm_offset_t addr)
50 {
51 	vm_offset_t kernmin;
52 
53 	/*
54 	 * The vm_page array is mapped at the beginning of the kernel map, but
55 	 * accesses to the array are not validated for now.  Handle the fact
56 	 * that KASAN must validate accesses before the vm_page array is
57 	 * initialized.
58 	 */
59 	kernmin = vm_page_array == NULL ? VM_MIN_KERNEL_ADDRESS :
60 	    (vm_offset_t)(vm_page_array + vm_page_array_size);
61 	return (addr < kernmin || addr >= VM_MAX_KERNEL_ADDRESS);
62 }
63 
64 static inline void
65 kasan_md_init(void)
66 {
67 }
68 
69 #endif /* KASAN */
70 
71 #endif /* !_MACHINE_ASAN_H_ */
72