1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2006 Peter Wemm 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 __FBSDID("$FreeBSD$"); 30 31 /* 32 * i386 machine dependent routines for kvm and minidumps. 33 */ 34 35 #include <sys/param.h> 36 #include <sys/endian.h> 37 #include <stdint.h> 38 #include <stdlib.h> 39 #include <string.h> 40 #include <unistd.h> 41 #include <vm/vm.h> 42 #include <kvm.h> 43 44 #include "../../sys/i386/include/minidump.h" 45 46 #include <limits.h> 47 48 #include "kvm_private.h" 49 #include "kvm_i386.h" 50 51 #define i386_round_page(x) roundup2((kvaddr_t)(x), I386_PAGE_SIZE) 52 53 struct vmstate { 54 struct minidumphdr hdr; 55 }; 56 57 static i386_pte_pae_t 58 _i386_pte_pae_get(kvm_t *kd, u_long pteindex) 59 { 60 i386_pte_pae_t *pte = _kvm_pmap_get(kd, pteindex, sizeof(*pte)); 61 62 return le64toh(*pte); 63 } 64 65 static i386_pte_t 66 _i386_pte_get(kvm_t *kd, u_long pteindex) 67 { 68 i386_pte_t *pte = _kvm_pmap_get(kd, pteindex, sizeof(*pte)); 69 70 return le32toh(*pte); 71 } 72 73 static int 74 _i386_minidump_probe(kvm_t *kd) 75 { 76 77 return (_kvm_probe_elf_kernel(kd, ELFCLASS32, EM_386) && 78 _kvm_is_minidump(kd)); 79 } 80 81 static void 82 _i386_minidump_freevtop(kvm_t *kd) 83 { 84 struct vmstate *vm = kd->vmst; 85 86 free(vm); 87 kd->vmst = NULL; 88 } 89 90 static int 91 _i386_minidump_initvtop(kvm_t *kd) 92 { 93 struct vmstate *vmst; 94 off_t off, dump_avail_off, sparse_off; 95 96 vmst = _kvm_malloc(kd, sizeof(*vmst)); 97 if (vmst == NULL) { 98 _kvm_err(kd, kd->program, "cannot allocate vm"); 99 return (-1); 100 } 101 kd->vmst = vmst; 102 if (pread(kd->pmfd, &vmst->hdr, sizeof(vmst->hdr), 0) != 103 sizeof(vmst->hdr)) { 104 _kvm_err(kd, kd->program, "cannot read dump header"); 105 return (-1); 106 } 107 if (strncmp(MINIDUMP_MAGIC, vmst->hdr.magic, sizeof(vmst->hdr.magic)) != 0) { 108 _kvm_err(kd, kd->program, "not a minidump for this platform"); 109 return (-1); 110 } 111 vmst->hdr.version = le32toh(vmst->hdr.version); 112 if (vmst->hdr.version != MINIDUMP_VERSION && vmst->hdr.version != 1) { 113 _kvm_err(kd, kd->program, "wrong minidump version. expected %d got %d", 114 MINIDUMP_VERSION, vmst->hdr.version); 115 return (-1); 116 } 117 vmst->hdr.msgbufsize = le32toh(vmst->hdr.msgbufsize); 118 vmst->hdr.bitmapsize = le32toh(vmst->hdr.bitmapsize); 119 vmst->hdr.ptesize = le32toh(vmst->hdr.ptesize); 120 vmst->hdr.kernbase = le32toh(vmst->hdr.kernbase); 121 vmst->hdr.paemode = le32toh(vmst->hdr.paemode); 122 vmst->hdr.dumpavailsize = vmst->hdr.version == MINIDUMP_VERSION ? 123 le32toh(vmst->hdr.dumpavailsize) : 0; 124 125 /* Skip header and msgbuf */ 126 dump_avail_off = I386_PAGE_SIZE + i386_round_page(vmst->hdr.msgbufsize); 127 128 /* Skip dump_avail */ 129 off = dump_avail_off + i386_round_page(vmst->hdr.dumpavailsize); 130 131 sparse_off = off + i386_round_page(vmst->hdr.bitmapsize) + 132 i386_round_page(vmst->hdr.ptesize); 133 if (_kvm_pt_init(kd, vmst->hdr.dumpavailsize, dump_avail_off, 134 vmst->hdr.bitmapsize, off, sparse_off, I386_PAGE_SIZE) == -1) { 135 return (-1); 136 } 137 off += i386_round_page(vmst->hdr.bitmapsize); 138 139 if (_kvm_pmap_init(kd, vmst->hdr.ptesize, off) == -1) { 140 return (-1); 141 } 142 off += i386_round_page(vmst->hdr.ptesize); 143 144 return (0); 145 } 146 147 static int 148 _i386_minidump_vatop_pae(kvm_t *kd, kvaddr_t va, off_t *pa) 149 { 150 struct vmstate *vm; 151 i386_physaddr_pae_t offset; 152 i386_pte_pae_t pte; 153 kvaddr_t pteindex; 154 i386_physaddr_pae_t a; 155 off_t ofs; 156 157 vm = kd->vmst; 158 offset = va & I386_PAGE_MASK; 159 160 if (va >= vm->hdr.kernbase) { 161 pteindex = (va - vm->hdr.kernbase) >> I386_PAGE_SHIFT; 162 if (pteindex >= vm->hdr.ptesize / sizeof(pte)) 163 goto invalid; 164 pte = _i386_pte_pae_get(kd, pteindex); 165 if ((pte & I386_PG_V) == 0) { 166 _kvm_err(kd, kd->program, 167 "_i386_minidump_vatop_pae: pte not valid"); 168 goto invalid; 169 } 170 a = pte & I386_PG_FRAME_PAE; 171 ofs = _kvm_pt_find(kd, a, I386_PAGE_SIZE); 172 if (ofs == -1) { 173 _kvm_err(kd, kd->program, 174 "_i386_minidump_vatop_pae: physical address 0x%jx not in minidump", 175 (uintmax_t)a); 176 goto invalid; 177 } 178 *pa = ofs + offset; 179 return (I386_PAGE_SIZE - offset); 180 } else { 181 _kvm_err(kd, kd->program, 182 "_i386_minidump_vatop_pae: virtual address 0x%jx not minidumped", 183 (uintmax_t)va); 184 goto invalid; 185 } 186 187 invalid: 188 _kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va); 189 return (0); 190 } 191 192 static int 193 _i386_minidump_vatop(kvm_t *kd, kvaddr_t va, off_t *pa) 194 { 195 struct vmstate *vm; 196 i386_physaddr_t offset; 197 i386_pte_t pte; 198 kvaddr_t pteindex; 199 i386_physaddr_t a; 200 off_t ofs; 201 202 vm = kd->vmst; 203 offset = va & I386_PAGE_MASK; 204 205 if (va >= vm->hdr.kernbase) { 206 pteindex = (va - vm->hdr.kernbase) >> I386_PAGE_SHIFT; 207 if (pteindex >= vm->hdr.ptesize / sizeof(pte)) 208 goto invalid; 209 pte = _i386_pte_get(kd, pteindex); 210 if ((pte & I386_PG_V) == 0) { 211 _kvm_err(kd, kd->program, 212 "_i386_minidump_vatop: pte not valid"); 213 goto invalid; 214 } 215 a = pte & I386_PG_FRAME; 216 ofs = _kvm_pt_find(kd, a, I386_PAGE_SIZE); 217 if (ofs == -1) { 218 _kvm_err(kd, kd->program, 219 "_i386_minidump_vatop: physical address 0x%jx not in minidump", 220 (uintmax_t)a); 221 goto invalid; 222 } 223 *pa = ofs + offset; 224 return (I386_PAGE_SIZE - offset); 225 } else { 226 _kvm_err(kd, kd->program, 227 "_i386_minidump_vatop: virtual address 0x%jx not minidumped", 228 (uintmax_t)va); 229 goto invalid; 230 } 231 232 invalid: 233 _kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va); 234 return (0); 235 } 236 237 static int 238 _i386_minidump_kvatop(kvm_t *kd, kvaddr_t va, off_t *pa) 239 { 240 241 if (ISALIVE(kd)) { 242 _kvm_err(kd, 0, "_i386_minidump_kvatop called in live kernel!"); 243 return (0); 244 } 245 if (kd->vmst->hdr.paemode) 246 return (_i386_minidump_vatop_pae(kd, va, pa)); 247 else 248 return (_i386_minidump_vatop(kd, va, pa)); 249 } 250 251 static vm_prot_t 252 _i386_entry_to_prot(uint64_t pte) 253 { 254 vm_prot_t prot = VM_PROT_READ; 255 256 /* Source: i386/pmap.c:pmap_protect() */ 257 if (pte & I386_PG_RW) 258 prot |= VM_PROT_WRITE; 259 if ((pte & I386_PG_NX) == 0) 260 prot |= VM_PROT_EXECUTE; 261 262 return prot; 263 } 264 265 struct i386_iter { 266 kvm_t *kd; 267 u_long nptes; 268 u_long pteindex; 269 }; 270 271 static void 272 _i386_iterator_init(struct i386_iter *it, kvm_t *kd) 273 { 274 struct vmstate *vm = kd->vmst; 275 276 it->kd = kd; 277 it->pteindex = 0; 278 if (vm->hdr.paemode) { 279 it->nptes = vm->hdr.ptesize / sizeof(i386_pte_pae_t); 280 } else { 281 it->nptes = vm->hdr.ptesize / sizeof(i386_pte_t); 282 } 283 return; 284 } 285 286 static int 287 _i386_iterator_next(struct i386_iter *it, u_long *pa, u_long *va, u_long *dva, 288 vm_prot_t *prot) 289 { 290 struct vmstate *vm = it->kd->vmst; 291 i386_pte_t pte32; 292 i386_pte_pae_t pte64; 293 int found = 0; 294 295 *dva = 0; 296 *pa = 0; 297 *va = 0; 298 *dva = 0; 299 *prot = 0; 300 for (; it->pteindex < it->nptes && found == 0; it->pteindex++) { 301 if (vm->hdr.paemode) { 302 pte64 = _i386_pte_pae_get(it->kd, it->pteindex); 303 if ((pte64 & I386_PG_V) == 0) 304 continue; 305 *prot = _i386_entry_to_prot(pte64); 306 *pa = pte64 & I386_PG_FRAME_PAE; 307 } else { 308 pte32 = _i386_pte_get(it->kd, it->pteindex); 309 if ((pte32 & I386_PG_V) == 0) 310 continue; 311 *prot = _i386_entry_to_prot(pte32); 312 *pa = pte32 & I386_PG_FRAME; 313 } 314 *va = vm->hdr.kernbase + (it->pteindex << I386_PAGE_SHIFT); 315 found = 1; 316 } 317 return found; 318 } 319 320 static int 321 _i386_minidump_walk_pages(kvm_t *kd, kvm_walk_pages_cb_t *cb, void *arg) 322 { 323 struct i386_iter it; 324 u_long dva, pa, va; 325 vm_prot_t prot; 326 327 _i386_iterator_init(&it, kd); 328 while (_i386_iterator_next(&it, &pa, &va, &dva, &prot)) { 329 if (!_kvm_visit_cb(kd, cb, arg, pa, va, dva, 330 prot, I386_PAGE_SIZE, 0)) { 331 return (0); 332 } 333 } 334 return (1); 335 } 336 337 static struct kvm_arch kvm_i386_minidump = { 338 .ka_probe = _i386_minidump_probe, 339 .ka_initvtop = _i386_minidump_initvtop, 340 .ka_freevtop = _i386_minidump_freevtop, 341 .ka_kvatop = _i386_minidump_kvatop, 342 .ka_native = _i386_native, 343 .ka_walk_pages = _i386_minidump_walk_pages, 344 }; 345 346 KVM_ARCH(kvm_i386_minidump); 347