1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2021 The FreeBSD Foundation 5 * Copyright (c) 2023 Juniper Networks, Inc. 6 * 7 * This software was developed by Mark Johnston under sponsorship from the 8 * FreeBSD Foundation. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions are 12 * met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in 17 * the documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #ifndef _MACHINE_MSAN_H_ 33 #define _MACHINE_MSAN_H_ 34 35 #ifdef KMSAN 36 37 #include <vm/vm.h> 38 #include <vm/pmap.h> 39 #include <vm/vm_page.h> 40 #include <machine/vmparam.h> 41 42 typedef uint32_t msan_orig_t; 43 44 /* 45 * Our 32-bit origin cells encode a 2-bit type and 30-bit pointer to a kernel 46 * instruction. The pointer is compressed by making it a positive offset 47 * relative to KERNBASE. 48 */ 49 #define KMSAN_ORIG_TYPE_SHIFT 30u 50 #define KMSAN_ORIG_PTR_MASK ((1ul << KMSAN_ORIG_TYPE_SHIFT) - 1) 51 52 static inline msan_orig_t 53 kmsan_md_orig_encode(int type, uintptr_t ptr) 54 { 55 return ((type << KMSAN_ORIG_TYPE_SHIFT) | 56 ((ptr & KMSAN_ORIG_PTR_MASK))); 57 } 58 59 static inline void 60 kmsan_md_orig_decode(msan_orig_t orig, int *type, uintptr_t *ptr) 61 { 62 *type = orig >> KMSAN_ORIG_TYPE_SHIFT; 63 *ptr = (orig & KMSAN_ORIG_PTR_MASK) | KERNBASE; 64 } 65 66 static inline vm_offset_t 67 kmsan_md_addr_to_shad(vm_offset_t addr) 68 { 69 return (addr - VM_MIN_KERNEL_ADDRESS + KMSAN_SHAD_MIN_ADDRESS); 70 } 71 72 static inline vm_offset_t 73 kmsan_md_addr_to_orig(vm_offset_t addr) 74 { 75 return (addr - VM_MIN_KERNEL_ADDRESS + KMSAN_ORIG_MIN_ADDRESS); 76 } 77 78 static inline bool 79 kmsan_md_unsupported(vm_offset_t addr) 80 { 81 /* 82 * It would be cheaper to use VM_MAX_KERNEL_ADDRESS as the upper bound, 83 * but we need to exclude device mappings above kernel_vm_end but within 84 * the kernel map. 85 */ 86 return (addr < VM_MIN_KERNEL_ADDRESS || addr >= kernel_vm_end); 87 } 88 89 #endif /* KMSAN */ 90 91 #endif /* !_MACHINE_MSAN_H_ */ 92