1 /* 2 * Windows crashdump 3 * 4 * Copyright (c) 2018 Virtuozzo International GmbH 5 * 6 * This work is licensed under the terms of the GNU GPL, version 2 or later. 7 * See the COPYING file in the top-level directory. 8 * 9 */ 10 11 #include "qemu/osdep.h" 12 #include "qemu/cutils.h" 13 #include "elf.h" 14 #include "exec/hwaddr.h" 15 #include "monitor/monitor.h" 16 #include "sysemu/kvm.h" 17 #include "sysemu/dump.h" 18 #include "sysemu/memory_mapping.h" 19 #include "sysemu/cpus.h" 20 #include "qapi/error.h" 21 #include "qapi/qmp/qerror.h" 22 #include "qemu/error-report.h" 23 #include "hw/misc/vmcoreinfo.h" 24 #include "win_dump.h" 25 26 static size_t win_dump_ptr_size(bool x64) 27 { 28 return x64 ? sizeof(uint64_t) : sizeof(uint32_t); 29 } 30 31 #define _WIN_DUMP_FIELD(f) (x64 ? h->x64.f : h->x32.f) 32 #define WIN_DUMP_FIELD(field) _WIN_DUMP_FIELD(field) 33 34 #define _WIN_DUMP_FIELD_PTR(f) (x64 ? (void *)&h->x64.f : (void *)&h->x32.f) 35 #define WIN_DUMP_FIELD_PTR(field) _WIN_DUMP_FIELD_PTR(field) 36 37 #define _WIN_DUMP_FIELD_SIZE(f) (x64 ? sizeof(h->x64.f) : sizeof(h->x32.f)) 38 #define WIN_DUMP_FIELD_SIZE(field) _WIN_DUMP_FIELD_SIZE(field) 39 40 static size_t win_dump_ctx_size(bool x64) 41 { 42 return x64 ? sizeof(WinContext64) : sizeof(WinContext32); 43 } 44 45 static size_t write_run(uint64_t base_page, uint64_t page_count, 46 int fd, Error **errp) 47 { 48 void *buf; 49 uint64_t addr = base_page << TARGET_PAGE_BITS; 50 uint64_t size = page_count << TARGET_PAGE_BITS; 51 uint64_t len, l; 52 size_t total = 0; 53 54 while (size) { 55 len = size; 56 57 buf = cpu_physical_memory_map(addr, &len, false); 58 if (!buf) { 59 error_setg(errp, "win-dump: failed to map physical range" 60 " 0x%016" PRIx64 "-0x%016" PRIx64, addr, addr + size - 1); 61 return 0; 62 } 63 64 l = qemu_write_full(fd, buf, len); 65 cpu_physical_memory_unmap(buf, addr, false, len); 66 if (l != len) { 67 error_setg(errp, QERR_IO_ERROR); 68 return 0; 69 } 70 71 addr += l; 72 size -= l; 73 total += l; 74 } 75 76 return total; 77 } 78 79 static void write_runs(DumpState *s, WinDumpHeader *h, bool x64, Error **errp) 80 { 81 uint64_t BasePage, PageCount; 82 Error *local_err = NULL; 83 int i; 84 85 for (i = 0; i < WIN_DUMP_FIELD(PhysicalMemoryBlock.NumberOfRuns); i++) { 86 BasePage = WIN_DUMP_FIELD(PhysicalMemoryBlock.Run[i].BasePage); 87 PageCount = WIN_DUMP_FIELD(PhysicalMemoryBlock.Run[i].PageCount); 88 s->written_size += write_run(BasePage, PageCount, s->fd, &local_err); 89 if (local_err) { 90 error_propagate(errp, local_err); 91 return; 92 } 93 } 94 } 95 96 static int cpu_read_ptr(bool x64, CPUState *cpu, uint64_t addr, uint64_t *ptr) 97 { 98 int ret; 99 uint32_t ptr32; 100 uint64_t ptr64; 101 102 ret = cpu_memory_rw_debug(cpu, addr, x64 ? (void *)&ptr64 : (void *)&ptr32, 103 win_dump_ptr_size(x64), 0); 104 105 *ptr = x64 ? ptr64 : ptr32; 106 107 return ret; 108 } 109 110 static void patch_mm_pfn_database(WinDumpHeader *h, bool x64, Error **errp) 111 { 112 if (cpu_memory_rw_debug(first_cpu, 113 WIN_DUMP_FIELD(KdDebuggerDataBlock) + KDBG_MM_PFN_DATABASE_OFFSET, 114 WIN_DUMP_FIELD_PTR(PfnDatabase), 115 WIN_DUMP_FIELD_SIZE(PfnDatabase), 0)) { 116 error_setg(errp, "win-dump: failed to read MmPfnDatabase"); 117 return; 118 } 119 } 120 121 static void patch_bugcheck_data(WinDumpHeader *h, bool x64, Error **errp) 122 { 123 uint64_t KiBugcheckData; 124 125 if (cpu_read_ptr(x64, first_cpu, 126 WIN_DUMP_FIELD(KdDebuggerDataBlock) + KDBG_KI_BUGCHECK_DATA_OFFSET, 127 &KiBugcheckData)) { 128 error_setg(errp, "win-dump: failed to read KiBugcheckData"); 129 return; 130 } 131 132 if (cpu_memory_rw_debug(first_cpu, KiBugcheckData, 133 WIN_DUMP_FIELD(BugcheckData), 134 WIN_DUMP_FIELD_SIZE(BugcheckData), 0)) { 135 error_setg(errp, "win-dump: failed to read bugcheck data"); 136 return; 137 } 138 139 /* 140 * If BugcheckCode wasn't saved, we consider guest OS as alive. 141 */ 142 143 if (!WIN_DUMP_FIELD(BugcheckCode)) { 144 *(uint32_t *)WIN_DUMP_FIELD_PTR(BugcheckCode) = LIVE_SYSTEM_DUMP; 145 } 146 } 147 148 /* 149 * This routine tries to correct mistakes in crashdump header. 150 */ 151 static void patch_header(WinDumpHeader *h, bool x64) 152 { 153 Error *local_err = NULL; 154 155 if (x64) { 156 h->x64.RequiredDumpSpace = sizeof(WinDumpHeader64) + 157 (h->x64.PhysicalMemoryBlock.NumberOfPages << TARGET_PAGE_BITS); 158 h->x64.PhysicalMemoryBlock.unused = 0; 159 h->x64.unused1 = 0; 160 } else { 161 h->x32.RequiredDumpSpace = sizeof(WinDumpHeader32) + 162 (h->x32.PhysicalMemoryBlock.NumberOfPages << TARGET_PAGE_BITS); 163 } 164 165 patch_mm_pfn_database(h, x64, &local_err); 166 if (local_err) { 167 warn_report_err(local_err); 168 local_err = NULL; 169 } 170 patch_bugcheck_data(h, x64, &local_err); 171 if (local_err) { 172 warn_report_err(local_err); 173 } 174 } 175 176 static bool check_header(WinDumpHeader *h, bool *x64, Error **errp) 177 { 178 const char Signature[] = "PAGE"; 179 180 if (memcmp(h->Signature, Signature, sizeof(h->Signature))) { 181 error_setg(errp, "win-dump: invalid header, expected '%.4s'," 182 " got '%.4s'", Signature, h->Signature); 183 return false; 184 } 185 186 if (!memcmp(h->ValidDump, "DUMP", sizeof(h->ValidDump))) { 187 *x64 = false; 188 } else if (!memcmp(h->ValidDump, "DU64", sizeof(h->ValidDump))) { 189 *x64 = true; 190 } else { 191 error_setg(errp, "win-dump: invalid header, expected 'DUMP' or 'DU64'," 192 " got '%.4s'", h->ValidDump); 193 return false; 194 } 195 196 return true; 197 } 198 199 static void check_kdbg(WinDumpHeader *h, bool x64, Error **errp) 200 { 201 const char OwnerTag[] = "KDBG"; 202 char read_OwnerTag[4]; 203 uint64_t KdDebuggerDataBlock = WIN_DUMP_FIELD(KdDebuggerDataBlock); 204 bool try_fallback = true; 205 206 try_again: 207 if (cpu_memory_rw_debug(first_cpu, 208 KdDebuggerDataBlock + KDBG_OWNER_TAG_OFFSET, 209 (uint8_t *)&read_OwnerTag, sizeof(read_OwnerTag), 0)) { 210 error_setg(errp, "win-dump: failed to read OwnerTag"); 211 return; 212 } 213 214 if (memcmp(read_OwnerTag, OwnerTag, sizeof(read_OwnerTag))) { 215 if (try_fallback) { 216 /* 217 * If attempt to use original KDBG failed 218 * (most likely because of its encryption), 219 * we try to use KDBG obtained by guest driver. 220 */ 221 222 KdDebuggerDataBlock = WIN_DUMP_FIELD(BugcheckParameter1); 223 try_fallback = false; 224 goto try_again; 225 } else { 226 error_setg(errp, "win-dump: invalid KDBG OwnerTag," 227 " expected '%.4s', got '%.4s'", 228 OwnerTag, read_OwnerTag); 229 return; 230 } 231 } 232 233 if (x64) { 234 h->x64.KdDebuggerDataBlock = KdDebuggerDataBlock; 235 } else { 236 h->x32.KdDebuggerDataBlock = KdDebuggerDataBlock; 237 } 238 } 239 240 struct saved_context { 241 WinContext ctx; 242 uint64_t addr; 243 }; 244 245 static void patch_and_save_context(WinDumpHeader *h, bool x64, 246 struct saved_context *saved_ctx, 247 Error **errp) 248 { 249 uint64_t KdDebuggerDataBlock = WIN_DUMP_FIELD(KdDebuggerDataBlock); 250 uint64_t KiProcessorBlock; 251 uint16_t OffsetPrcbContext; 252 CPUState *cpu; 253 int i = 0; 254 255 if (cpu_read_ptr(x64, first_cpu, 256 KdDebuggerDataBlock + KDBG_KI_PROCESSOR_BLOCK_OFFSET, 257 &KiProcessorBlock)) { 258 error_setg(errp, "win-dump: failed to read KiProcessorBlock"); 259 return; 260 } 261 262 if (cpu_memory_rw_debug(first_cpu, 263 KdDebuggerDataBlock + KDBG_OFFSET_PRCB_CONTEXT_OFFSET, 264 (uint8_t *)&OffsetPrcbContext, sizeof(OffsetPrcbContext), 0)) { 265 error_setg(errp, "win-dump: failed to read OffsetPrcbContext"); 266 return; 267 } 268 269 CPU_FOREACH(cpu) { 270 X86CPU *x86_cpu = X86_CPU(cpu); 271 CPUX86State *env = &x86_cpu->env; 272 uint64_t Prcb; 273 uint64_t Context; 274 WinContext ctx; 275 276 if (cpu_read_ptr(x64, first_cpu, 277 KiProcessorBlock + i * win_dump_ptr_size(x64), 278 &Prcb)) { 279 error_setg(errp, "win-dump: failed to read" 280 " CPU #%d PRCB location", i); 281 return; 282 } 283 284 if (cpu_read_ptr(x64, first_cpu, 285 Prcb + OffsetPrcbContext, 286 &Context)) { 287 error_setg(errp, "win-dump: failed to read" 288 " CPU #%d ContextFrame location", i); 289 return; 290 } 291 292 saved_ctx[i].addr = Context; 293 294 if (x64) { 295 ctx.x64 = (WinContext64){ 296 .ContextFlags = WIN_CTX64_ALL, 297 .MxCsr = env->mxcsr, 298 299 .SegEs = env->segs[0].selector, 300 .SegCs = env->segs[1].selector, 301 .SegSs = env->segs[2].selector, 302 .SegDs = env->segs[3].selector, 303 .SegFs = env->segs[4].selector, 304 .SegGs = env->segs[5].selector, 305 .EFlags = cpu_compute_eflags(env), 306 307 .Dr0 = env->dr[0], 308 .Dr1 = env->dr[1], 309 .Dr2 = env->dr[2], 310 .Dr3 = env->dr[3], 311 .Dr6 = env->dr[6], 312 .Dr7 = env->dr[7], 313 314 .Rax = env->regs[R_EAX], 315 .Rbx = env->regs[R_EBX], 316 .Rcx = env->regs[R_ECX], 317 .Rdx = env->regs[R_EDX], 318 .Rsp = env->regs[R_ESP], 319 .Rbp = env->regs[R_EBP], 320 .Rsi = env->regs[R_ESI], 321 .Rdi = env->regs[R_EDI], 322 .R8 = env->regs[8], 323 .R9 = env->regs[9], 324 .R10 = env->regs[10], 325 .R11 = env->regs[11], 326 .R12 = env->regs[12], 327 .R13 = env->regs[13], 328 .R14 = env->regs[14], 329 .R15 = env->regs[15], 330 331 .Rip = env->eip, 332 .FltSave = { 333 .MxCsr = env->mxcsr, 334 }, 335 }; 336 } else { 337 ctx.x32 = (WinContext32){ 338 .ContextFlags = WIN_CTX32_FULL | WIN_CTX_DBG, 339 340 .SegEs = env->segs[0].selector, 341 .SegCs = env->segs[1].selector, 342 .SegSs = env->segs[2].selector, 343 .SegDs = env->segs[3].selector, 344 .SegFs = env->segs[4].selector, 345 .SegGs = env->segs[5].selector, 346 .EFlags = cpu_compute_eflags(env), 347 348 .Dr0 = env->dr[0], 349 .Dr1 = env->dr[1], 350 .Dr2 = env->dr[2], 351 .Dr3 = env->dr[3], 352 .Dr6 = env->dr[6], 353 .Dr7 = env->dr[7], 354 355 .Eax = env->regs[R_EAX], 356 .Ebx = env->regs[R_EBX], 357 .Ecx = env->regs[R_ECX], 358 .Edx = env->regs[R_EDX], 359 .Esp = env->regs[R_ESP], 360 .Ebp = env->regs[R_EBP], 361 .Esi = env->regs[R_ESI], 362 .Edi = env->regs[R_EDI], 363 364 .Eip = env->eip, 365 }; 366 } 367 368 if (cpu_memory_rw_debug(first_cpu, Context, 369 &saved_ctx[i].ctx, win_dump_ctx_size(x64), 0)) { 370 error_setg(errp, "win-dump: failed to save CPU #%d context", i); 371 return; 372 } 373 374 if (cpu_memory_rw_debug(first_cpu, Context, 375 &ctx, win_dump_ctx_size(x64), 1)) { 376 error_setg(errp, "win-dump: failed to write CPU #%d context", i); 377 return; 378 } 379 380 i++; 381 } 382 } 383 384 static void restore_context(WinDumpHeader *h, bool x64, 385 struct saved_context *saved_ctx) 386 { 387 int i; 388 389 for (i = 0; i < WIN_DUMP_FIELD(NumberProcessors); i++) { 390 if (cpu_memory_rw_debug(first_cpu, saved_ctx[i].addr, 391 &saved_ctx[i].ctx, win_dump_ctx_size(x64), 1)) { 392 warn_report("win-dump: failed to restore CPU #%d context", i); 393 } 394 } 395 } 396 397 void create_win_dump(DumpState *s, Error **errp) 398 { 399 WinDumpHeader *h = (void *)(s->guest_note + VMCOREINFO_ELF_NOTE_HDR_SIZE); 400 X86CPU *first_x86_cpu = X86_CPU(first_cpu); 401 uint64_t saved_cr3 = first_x86_cpu->env.cr[3]; 402 struct saved_context *saved_ctx = NULL; 403 Error *local_err = NULL; 404 bool x64 = true; 405 size_t hdr_size; 406 407 if (s->guest_note_size != VMCOREINFO_WIN_DUMP_NOTE_SIZE32 && 408 s->guest_note_size != VMCOREINFO_WIN_DUMP_NOTE_SIZE64) { 409 error_setg(errp, "win-dump: invalid vmcoreinfo note size"); 410 return; 411 } 412 413 if (!check_header(h, &x64, &local_err)) { 414 error_propagate(errp, local_err); 415 return; 416 } 417 418 hdr_size = x64 ? sizeof(WinDumpHeader64) : sizeof(WinDumpHeader32); 419 420 /* 421 * Further access to kernel structures by virtual addresses 422 * should be made from system context. 423 */ 424 425 first_x86_cpu->env.cr[3] = WIN_DUMP_FIELD(DirectoryTableBase); 426 427 check_kdbg(h, x64, &local_err); 428 if (local_err) { 429 error_propagate(errp, local_err); 430 goto out_cr3; 431 } 432 433 patch_header(h, x64); 434 435 saved_ctx = g_new(struct saved_context, WIN_DUMP_FIELD(NumberProcessors)); 436 437 /* 438 * Always patch context because there is no way 439 * to determine if the system-saved context is valid 440 */ 441 442 patch_and_save_context(h, x64, saved_ctx, &local_err); 443 if (local_err) { 444 error_propagate(errp, local_err); 445 goto out_free; 446 } 447 448 s->total_size = WIN_DUMP_FIELD(RequiredDumpSpace); 449 450 s->written_size = qemu_write_full(s->fd, h, hdr_size); 451 if (s->written_size != hdr_size) { 452 error_setg(errp, QERR_IO_ERROR); 453 goto out_restore; 454 } 455 456 write_runs(s, h, x64, &local_err); 457 if (local_err) { 458 error_propagate(errp, local_err); 459 goto out_restore; 460 } 461 462 out_restore: 463 restore_context(h, x64, saved_ctx); 464 out_free: 465 g_free(saved_ctx); 466 out_cr3: 467 first_x86_cpu->env.cr[3] = saved_cr3; 468 469 return; 470 } 471