1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 2008, Juniper Networks, Inc. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the author nor the names of any co-contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #include <sys/cdefs.h> 32 __FBSDID("$FreeBSD$"); 33 34 #include <sys/param.h> 35 #include <sys/endian.h> 36 #include <sys/kerneldump.h> 37 #include <sys/mman.h> 38 39 #include <elf.h> 40 #include <kvm.h> 41 #include <limits.h> 42 #include <stdlib.h> 43 #include <string.h> 44 45 #include "kvm_private.h" 46 47 struct vmstate { 48 void *map; 49 size_t mapsz; 50 size_t dmphdrsz; 51 Elf64_Ehdr *eh; 52 Elf64_Phdr *ph; 53 }; 54 55 static int 56 valid_elf_header(kvm_t *kd, Elf64_Ehdr *eh) 57 { 58 59 if (!IS_ELF(*eh)) 60 return (0); 61 if (eh->e_ident[EI_CLASS] != ELFCLASS64) 62 return (0); 63 if (eh->e_ident[EI_DATA] != ELFDATA2MSB && 64 eh->e_ident[EI_DATA] != ELFDATA2LSB) 65 return (0); 66 if (eh->e_ident[EI_VERSION] != EV_CURRENT) 67 return (0); 68 if (eh->e_ident[EI_OSABI] != ELFOSABI_STANDALONE) 69 return (0); 70 if (_kvm16toh(kd, eh->e_type) != ET_CORE) 71 return (0); 72 if (_kvm16toh(kd, eh->e_machine) != EM_PPC64) 73 return (0); 74 /* Can't think of anything else to check... */ 75 return (1); 76 } 77 78 static size_t 79 dump_header_size(struct kerneldumpheader *dh) 80 { 81 82 if (strcmp(dh->magic, KERNELDUMPMAGIC) != 0) 83 return (0); 84 if (strcmp(dh->architecture, "powerpc64") != 0 && 85 strcmp(dh->architecture, "powerpc64le") != 0) 86 return (0); 87 /* That should do it... */ 88 return (sizeof(*dh)); 89 } 90 91 /* 92 * Map the ELF headers into the process' address space. We do this in two 93 * steps: first the ELF header itself and using that information the whole 94 * set of headers. 95 */ 96 static int 97 powerpc_maphdrs(kvm_t *kd) 98 { 99 struct vmstate *vm; 100 size_t mapsz; 101 102 vm = kd->vmst; 103 104 vm->mapsz = sizeof(*vm->eh) + sizeof(struct kerneldumpheader); 105 vm->map = mmap(NULL, vm->mapsz, PROT_READ, MAP_PRIVATE, kd->pmfd, 0); 106 if (vm->map == MAP_FAILED) { 107 _kvm_err(kd, kd->program, "cannot map corefile"); 108 return (-1); 109 } 110 vm->dmphdrsz = 0; 111 vm->eh = vm->map; 112 if (!valid_elf_header(kd, vm->eh)) { 113 /* 114 * Hmmm, no ELF header. Maybe we still have a dump header. 115 * This is normal when the core file wasn't created by 116 * savecore(8), but instead was dumped over TFTP. We can 117 * easily skip the dump header... 118 */ 119 vm->dmphdrsz = dump_header_size(vm->map); 120 if (vm->dmphdrsz == 0) 121 goto inval; 122 vm->eh = (void *)((uintptr_t)vm->map + vm->dmphdrsz); 123 if (!valid_elf_header(kd, vm->eh)) 124 goto inval; 125 } 126 mapsz = _kvm16toh(kd, vm->eh->e_phentsize) * 127 _kvm16toh(kd, vm->eh->e_phnum) + _kvm64toh(kd, vm->eh->e_phoff); 128 munmap(vm->map, vm->mapsz); 129 130 /* Map all headers. */ 131 vm->mapsz = vm->dmphdrsz + mapsz; 132 vm->map = mmap(NULL, vm->mapsz, PROT_READ, MAP_PRIVATE, kd->pmfd, 0); 133 if (vm->map == MAP_FAILED) { 134 _kvm_err(kd, kd->program, "cannot map corefile headers"); 135 return (-1); 136 } 137 vm->eh = (void *)((uintptr_t)vm->map + vm->dmphdrsz); 138 vm->ph = (void *)((uintptr_t)vm->eh + 139 (uintptr_t)_kvm64toh(kd, vm->eh->e_phoff)); 140 return (0); 141 142 inval: 143 _kvm_err(kd, kd->program, "invalid corefile"); 144 return (-1); 145 } 146 147 /* 148 * Determine the offset within the corefile corresponding the virtual 149 * address. Return the number of contiguous bytes in the corefile or 150 * 0 when the virtual address is invalid. 151 */ 152 static size_t 153 powerpc64_va2off(kvm_t *kd, kvaddr_t va, off_t *ofs) 154 { 155 struct vmstate *vm = kd->vmst; 156 Elf64_Phdr *ph; 157 int nph; 158 159 ph = vm->ph; 160 nph = _kvm16toh(kd, vm->eh->e_phnum); 161 while (nph && (va < _kvm64toh(kd, ph->p_vaddr) || 162 va >= _kvm64toh(kd, ph->p_vaddr) + _kvm64toh(kd, ph->p_memsz))) { 163 nph--; 164 ph = (void *)((uintptr_t)ph + 165 _kvm16toh(kd, vm->eh->e_phentsize)); 166 } 167 if (nph == 0) 168 return (0); 169 170 /* Segment found. Return file offset and range. */ 171 *ofs = vm->dmphdrsz + _kvm64toh(kd, ph->p_offset) + 172 (va - _kvm64toh(kd, ph->p_vaddr)); 173 return (_kvm64toh(kd, ph->p_memsz) - 174 (va - _kvm64toh(kd, ph->p_vaddr))); 175 } 176 177 static void 178 _powerpc64_freevtop(kvm_t *kd) 179 { 180 struct vmstate *vm = kd->vmst; 181 182 if (vm->eh != MAP_FAILED) 183 munmap(vm->eh, vm->mapsz); 184 free(vm); 185 kd->vmst = NULL; 186 } 187 188 static int 189 _powerpc64_probe(kvm_t *kd) 190 { 191 192 return (_kvm_probe_elf_kernel(kd, ELFCLASS64, EM_PPC64) && 193 kd->nlehdr.e_ident[EI_DATA] == ELFDATA2MSB); 194 } 195 196 static int 197 _powerpc64le_probe(kvm_t *kd) 198 { 199 200 return (_kvm_probe_elf_kernel(kd, ELFCLASS64, EM_PPC64) && 201 kd->nlehdr.e_ident[EI_DATA] == ELFDATA2LSB); 202 } 203 204 static int 205 _powerpc64_initvtop(kvm_t *kd) 206 { 207 208 kd->vmst = (struct vmstate *)_kvm_malloc(kd, sizeof(*kd->vmst)); 209 if (kd->vmst == NULL) 210 return (-1); 211 212 if (powerpc_maphdrs(kd) == -1) 213 return (-1); 214 215 return (0); 216 } 217 218 static int 219 _powerpc64_kvatop(kvm_t *kd, kvaddr_t va, off_t *ofs) 220 { 221 struct vmstate *vm; 222 223 vm = kd->vmst; 224 if (_kvm64toh(kd, vm->ph->p_paddr) == 0xffffffffffffffff) 225 return ((int)powerpc64_va2off(kd, va, ofs)); 226 227 _kvm_err(kd, kd->program, "Raw corefile not supported"); 228 return (0); 229 } 230 231 static int 232 _powerpc64_native(kvm_t *kd __unused) 233 { 234 235 #if defined(__powerpc64__) && BYTE_ORDER == BIG_ENDIAN 236 return (1); 237 #else 238 return (0); 239 #endif 240 } 241 242 static int 243 _powerpc64le_native(kvm_t *kd __unused) 244 { 245 246 #if defined(__powerpc64__) && BYTE_ORDER == LITTLE_ENDIAN 247 return (1); 248 #else 249 return (0); 250 #endif 251 } 252 253 static struct kvm_arch kvm_powerpc64 = { 254 .ka_probe = _powerpc64_probe, 255 .ka_initvtop = _powerpc64_initvtop, 256 .ka_freevtop = _powerpc64_freevtop, 257 .ka_kvatop = _powerpc64_kvatop, 258 .ka_native = _powerpc64_native, 259 }; 260 261 static struct kvm_arch kvm_powerpc64le = { 262 .ka_probe = _powerpc64le_probe, 263 .ka_initvtop = _powerpc64_initvtop, 264 .ka_freevtop = _powerpc64_freevtop, 265 .ka_kvatop = _powerpc64_kvatop, 266 .ka_native = _powerpc64le_native, 267 }; 268 269 KVM_ARCH(kvm_powerpc64); 270 KVM_ARCH(kvm_powerpc64le); 271