| 1 | /* |
| 2 | * Windows crashdump (x86 specific implementations) |
| 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 "system/dump.h" |
| 13 | #include "system/physmem.h" |
| 14 | #include "qapi/error.h" |
| 15 | #include "qemu/error-report.h" |
| 16 | #include "exec/cpu-defs.h" |
| 17 | #include "hw/core/cpu.h" |
| 18 | #include "qemu/win_dump_defs.h" |
| 19 | #include "win_dump.h" |
| 20 | #include "cpu.h" |
| 21 | #include "qemu/bswap.h" |
| 22 | #include "hw/misc/vmcoreinfo.h" |
| 23 | #include "migration/misc.h" |
| 24 | #include "standard-headers/linux/qemu_fw_cfg.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 | int eno; |
| 53 | size_t total = 0; |
| 54 | |
| 55 | while (size) { |
| 56 | len = size; |
| 57 | |
| 58 | buf = physical_memory_map(addr, &len, false); |
| 59 | if (!buf) { |
| 60 | error_setg(errp, "win-dump: failed to map physical range" |
| 61 | " 0x%016" PRIx64 "-0x%016" PRIx64, addr, addr + size - 1); |
| 62 | return 0; |
| 63 | } |
| 64 | |
| 65 | l = qemu_write_full(fd, buf, len); |
| 66 | eno = errno; |
| 67 | physical_memory_unmap(buf, addr, false, len); |
| 68 | if (l != len) { |
| 69 | error_setg_errno(errp, eno, "win-dump: failed to save memory"); |
| 70 | return 0; |
| 71 | } |
| 72 | |
| 73 | addr += l; |
| 74 | size -= l; |
| 75 | total += l; |
| 76 | } |
| 77 | |
| 78 | return total; |
| 79 | } |
| 80 | |
| 81 | static void write_runs(DumpState *s, WinDumpHeader *h, bool x64, Error **errp) |
| 82 | { |
| 83 | uint64_t BasePage, PageCount; |
| 84 | Error *local_err = NULL; |
| 85 | int i; |
| 86 | |
| 87 | for (i = 0; i < WIN_DUMP_FIELD(PhysicalMemoryBlock.NumberOfRuns); i++) { |
| 88 | BasePage = WIN_DUMP_FIELD(PhysicalMemoryBlock.Run[i].BasePage); |
| 89 | PageCount = WIN_DUMP_FIELD(PhysicalMemoryBlock.Run[i].PageCount); |
| 90 | s->written_size += write_run(BasePage, PageCount, s->fd, &local_err); |
| 91 | if (local_err) { |
| 92 | error_propagate(errp, local_err); |
| 93 | return; |
| 94 | } |
| 95 | } |
| 96 | } |
| 97 | |
| 98 | static int cpu_read_ptr(bool x64, CPUState *cpu, uint64_t addr, uint64_t *ptr) |
| 99 | { |
| 100 | int ret; |
| 101 | uint32_t ptr32; |
| 102 | uint64_t ptr64; |
| 103 | |
| 104 | ret = cpu_memory_rw_debug(cpu, addr, x64 ? (void *)&ptr64 : (void *)&ptr32, |
| 105 | win_dump_ptr_size(x64), 0); |
| 106 | |
| 107 | *ptr = x64 ? ptr64 : ptr32; |
| 108 | |
| 109 | return ret; |
| 110 | } |
| 111 | |
| 112 | static void patch_mm_pfn_database(WinDumpHeader *h, bool x64, Error **errp) |
| 113 | { |
| 114 | if (cpu_memory_rw_debug(first_cpu, |
| 115 | WIN_DUMP_FIELD(KdDebuggerDataBlock) + KDBG_MM_PFN_DATABASE_OFFSET, |
| 116 | WIN_DUMP_FIELD_PTR(PfnDatabase), |
| 117 | WIN_DUMP_FIELD_SIZE(PfnDatabase), 0)) { |
| 118 | error_setg(errp, "win-dump: failed to read MmPfnDatabase"); |
| 119 | return; |
| 120 | } |
| 121 | } |
| 122 | |
| 123 | static void patch_bugcheck_data(WinDumpHeader *h, bool x64, Error **errp) |
| 124 | { |
| 125 | uint64_t KiBugcheckData; |
| 126 | |
| 127 | if (cpu_read_ptr(x64, first_cpu, |
| 128 | WIN_DUMP_FIELD(KdDebuggerDataBlock) + KDBG_KI_BUGCHECK_DATA_OFFSET, |
| 129 | &KiBugcheckData)) { |
| 130 | error_setg(errp, "win-dump: failed to read KiBugcheckData"); |
| 131 | return; |
| 132 | } |
| 133 | |
| 134 | if (cpu_memory_rw_debug(first_cpu, KiBugcheckData, |
| 135 | WIN_DUMP_FIELD(BugcheckData), |
| 136 | WIN_DUMP_FIELD_SIZE(BugcheckData), 0)) { |
| 137 | error_setg(errp, "win-dump: failed to read bugcheck data"); |
| 138 | return; |
| 139 | } |
| 140 | |
| 141 | /* |
| 142 | * If BugcheckCode wasn't saved, we consider guest OS as alive. |
| 143 | */ |
| 144 | |
| 145 | if (!WIN_DUMP_FIELD(BugcheckCode)) { |
| 146 | *(uint32_t *)WIN_DUMP_FIELD_PTR(BugcheckCode) = LIVE_SYSTEM_DUMP; |
| 147 | } |
| 148 | } |
| 149 | |
| 150 | /* |
| 151 | * This routine tries to correct mistakes in crashdump header. |
| 152 | */ |
| 153 | static void patch_header(WinDumpHeader *h, bool x64) |
| 154 | { |
| 155 | Error *local_err = NULL; |
| 156 | |
| 157 | if (x64) { |
| 158 | h->x64.RequiredDumpSpace = sizeof(WinDumpHeader64) + |
| 159 | (h->x64.PhysicalMemoryBlock.NumberOfPages << TARGET_PAGE_BITS); |
| 160 | h->x64.PhysicalMemoryBlock.unused = 0; |
| 161 | h->x64.unused1 = 0; |
| 162 | } else { |
| 163 | h->x32.RequiredDumpSpace = sizeof(WinDumpHeader32) + |
| 164 | (h->x32.PhysicalMemoryBlock.NumberOfPages << TARGET_PAGE_BITS); |
| 165 | } |
| 166 | |
| 167 | patch_mm_pfn_database(h, x64, &local_err); |
| 168 | if (local_err) { |
| 169 | warn_report_err(local_err); |
| 170 | local_err = NULL; |
| 171 | } |
| 172 | patch_bugcheck_data(h, x64, &local_err); |
| 173 | if (local_err) { |
| 174 | warn_report_err(local_err); |
| 175 | } |
| 176 | } |
| 177 | |
| 178 | static bool check_header(WinDumpHeader *h, bool *x64, Error **errp) |
| 179 | { |
| 180 | const char Signature[] = "PAGE"; |
| 181 | |
| 182 | if (memcmp(h->Signature, Signature, sizeof(h->Signature))) { |
| 183 | error_setg(errp, "win-dump: invalid header, expected '%.4s'," |
| 184 | " got '%.4s'", Signature, h->Signature); |
| 185 | return false; |
| 186 | } |
| 187 | |
| 188 | if (!memcmp(h->ValidDump, "DUMP", sizeof(h->ValidDump))) { |
| 189 | *x64 = false; |
| 190 | } else if (!memcmp(h->ValidDump, "DU64", sizeof(h->ValidDump))) { |
| 191 | *x64 = true; |
| 192 | } else { |
| 193 | error_setg(errp, "win-dump: invalid header, expected 'DUMP' or 'DU64'," |
| 194 | " got '%.4s'", h->ValidDump); |
| 195 | return false; |
| 196 | } |
| 197 | |
| 198 | return true; |
| 199 | } |
| 200 | |
| 201 | static void check_kdbg(WinDumpHeader *h, bool x64, Error **errp) |
| 202 | { |
| 203 | const char OwnerTag[] = "KDBG"; |
| 204 | char read_OwnerTag[4]; |
| 205 | uint64_t KdDebuggerDataBlock = WIN_DUMP_FIELD(KdDebuggerDataBlock); |
| 206 | bool try_fallback = true; |
| 207 | |
| 208 | try_again: |
| 209 | if (cpu_memory_rw_debug(first_cpu, |
| 210 | KdDebuggerDataBlock + KDBG_OWNER_TAG_OFFSET, |
| 211 | (uint8_t *)&read_OwnerTag, sizeof(read_OwnerTag), 0)) { |
| 212 | error_setg(errp, "win-dump: failed to read OwnerTag"); |
| 213 | return; |
| 214 | } |
| 215 | |
| 216 | if (memcmp(read_OwnerTag, OwnerTag, sizeof(read_OwnerTag))) { |
| 217 | if (try_fallback) { |
| 218 | /* |
| 219 | * If attempt to use original KDBG failed |
| 220 | * (most likely because of its encryption), |
| 221 | * we try to use KDBG obtained by guest driver. |
| 222 | */ |
| 223 | |
| 224 | KdDebuggerDataBlock = WIN_DUMP_FIELD(BugcheckParameter1); |
| 225 | try_fallback = false; |
| 226 | goto try_again; |
| 227 | } else { |
| 228 | error_setg(errp, "win-dump: invalid KDBG OwnerTag," |
| 229 | " expected '%.4s', got '%.4s'", |
| 230 | OwnerTag, read_OwnerTag); |
| 231 | return; |
| 232 | } |
| 233 | } |
| 234 | |
| 235 | if (x64) { |
| 236 | h->x64.KdDebuggerDataBlock = KdDebuggerDataBlock; |
| 237 | } else { |
| 238 | h->x32.KdDebuggerDataBlock = KdDebuggerDataBlock; |
| 239 | } |
| 240 | } |
| 241 | |
| 242 | struct saved_context { |
| 243 | WinContext ctx; |
| 244 | uint64_t addr; |
| 245 | }; |
| 246 | |
| 247 | static void patch_and_save_context(WinDumpHeader *h, bool x64, |
| 248 | struct saved_context *saved_ctx, |
| 249 | Error **errp) |
| 250 | { |
| 251 | uint64_t KdDebuggerDataBlock = WIN_DUMP_FIELD(KdDebuggerDataBlock); |
| 252 | uint64_t KiProcessorBlock; |
| 253 | uint16_t OffsetPrcbContext; |
| 254 | CPUState *cpu; |
| 255 | int i = 0; |
| 256 | |
| 257 | if (cpu_read_ptr(x64, first_cpu, |
| 258 | KdDebuggerDataBlock + KDBG_KI_PROCESSOR_BLOCK_OFFSET, |
| 259 | &KiProcessorBlock)) { |
| 260 | error_setg(errp, "win-dump: failed to read KiProcessorBlock"); |
| 261 | return; |
| 262 | } |
| 263 | |
| 264 | if (cpu_memory_rw_debug(first_cpu, |
| 265 | KdDebuggerDataBlock + KDBG_OFFSET_PRCB_CONTEXT_OFFSET, |
| 266 | (uint8_t *)&OffsetPrcbContext, sizeof(OffsetPrcbContext), 0)) { |
| 267 | error_setg(errp, "win-dump: failed to read OffsetPrcbContext"); |
| 268 | return; |
| 269 | } |
| 270 | |
| 271 | CPU_FOREACH(cpu) { |
| 272 | X86CPU *x86_cpu = X86_CPU(cpu); |
| 273 | CPUX86State *env = &x86_cpu->env; |
| 274 | uint64_t Prcb; |
| 275 | uint64_t Context; |
| 276 | WinContext ctx; |
| 277 | |
| 278 | if (i >= WIN_DUMP_FIELD(NumberProcessors)) { |
| 279 | warn_report("win-dump: number of QEMU CPUs is bigger than" |
| 280 | " NumberProcessors (%u) in guest Windows", |
| 281 | WIN_DUMP_FIELD(NumberProcessors)); |
| 282 | return; |
| 283 | } |
| 284 | |
| 285 | if (cpu_read_ptr(x64, first_cpu, |
| 286 | KiProcessorBlock + i * win_dump_ptr_size(x64), |
| 287 | &Prcb)) { |
| 288 | error_setg(errp, "win-dump: failed to read" |
| 289 | " CPU #%d PRCB location", i); |
| 290 | return; |
| 291 | } |
| 292 | |
| 293 | if (cpu_read_ptr(x64, first_cpu, |
| 294 | Prcb + OffsetPrcbContext, |
| 295 | &Context)) { |
| 296 | error_setg(errp, "win-dump: failed to read" |
| 297 | " CPU #%d ContextFrame location", i); |
| 298 | return; |
| 299 | } |
| 300 | |
| 301 | saved_ctx[i].addr = Context; |
| 302 | |
| 303 | if (x64) { |
| 304 | ctx.x64 = (WinContext64){ |
| 305 | .ContextFlags = WIN_CTX64_ALL, |
| 306 | .MxCsr = env->mxcsr, |
| 307 | |
| 308 | .SegEs = env->segs[0].selector, |
| 309 | .SegCs = env->segs[1].selector, |
| 310 | .SegSs = env->segs[2].selector, |
| 311 | .SegDs = env->segs[3].selector, |
| 312 | .SegFs = env->segs[4].selector, |
| 313 | .SegGs = env->segs[5].selector, |
| 314 | .EFlags = cpu_compute_eflags(env), |
| 315 | |
| 316 | .Dr0 = env->dr[0], |
| 317 | .Dr1 = env->dr[1], |
| 318 | .Dr2 = env->dr[2], |
| 319 | .Dr3 = env->dr[3], |
| 320 | .Dr6 = env->dr[6], |
| 321 | .Dr7 = env->dr[7], |
| 322 | |
| 323 | .Rax = env->regs[R_EAX], |
| 324 | .Rbx = env->regs[R_EBX], |
| 325 | .Rcx = env->regs[R_ECX], |
| 326 | .Rdx = env->regs[R_EDX], |
| 327 | .Rsp = env->regs[R_ESP], |
| 328 | .Rbp = env->regs[R_EBP], |
| 329 | .Rsi = env->regs[R_ESI], |
| 330 | .Rdi = env->regs[R_EDI], |
| 331 | .R8 = env->regs[8], |
| 332 | .R9 = env->regs[9], |
| 333 | .R10 = env->regs[10], |
| 334 | .R11 = env->regs[11], |
| 335 | .R12 = env->regs[12], |
| 336 | .R13 = env->regs[13], |
| 337 | .R14 = env->regs[14], |
| 338 | .R15 = env->regs[15], |
| 339 | |
| 340 | .Rip = env->eip, |
| 341 | .FltSave = { |
| 342 | .MxCsr = env->mxcsr, |
| 343 | }, |
| 344 | }; |
| 345 | } else { |
| 346 | ctx.x32 = (WinContext32){ |
| 347 | .ContextFlags = WIN_CTX32_FULL | WIN_CTX_DBG, |
| 348 | |
| 349 | .SegEs = env->segs[0].selector, |
| 350 | .SegCs = env->segs[1].selector, |
| 351 | .SegSs = env->segs[2].selector, |
| 352 | .SegDs = env->segs[3].selector, |
| 353 | .SegFs = env->segs[4].selector, |
| 354 | .SegGs = env->segs[5].selector, |
| 355 | .EFlags = cpu_compute_eflags(env), |
| 356 | |
| 357 | .Dr0 = env->dr[0], |
| 358 | .Dr1 = env->dr[1], |
| 359 | .Dr2 = env->dr[2], |
| 360 | .Dr3 = env->dr[3], |
| 361 | .Dr6 = env->dr[6], |
| 362 | .Dr7 = env->dr[7], |
| 363 | |
| 364 | .Eax = env->regs[R_EAX], |
| 365 | .Ebx = env->regs[R_EBX], |
| 366 | .Ecx = env->regs[R_ECX], |
| 367 | .Edx = env->regs[R_EDX], |
| 368 | .Esp = env->regs[R_ESP], |
| 369 | .Ebp = env->regs[R_EBP], |
| 370 | .Esi = env->regs[R_ESI], |
| 371 | .Edi = env->regs[R_EDI], |
| 372 | |
| 373 | .Eip = env->eip, |
| 374 | }; |
| 375 | } |
| 376 | |
| 377 | if (cpu_memory_rw_debug(first_cpu, Context, |
| 378 | &saved_ctx[i].ctx, win_dump_ctx_size(x64), 0)) { |
| 379 | error_setg(errp, "win-dump: failed to save CPU #%d context", i); |
| 380 | return; |
| 381 | } |
| 382 | |
| 383 | if (cpu_memory_rw_debug(first_cpu, Context, |
| 384 | &ctx, win_dump_ctx_size(x64), 1)) { |
| 385 | error_setg(errp, "win-dump: failed to write CPU #%d context", i); |
| 386 | return; |
| 387 | } |
| 388 | |
| 389 | i++; |
| 390 | } |
| 391 | } |
| 392 | |
| 393 | static void restore_context(WinDumpHeader *h, bool x64, |
| 394 | struct saved_context *saved_ctx) |
| 395 | { |
| 396 | int i; |
| 397 | |
| 398 | for (i = 0; i < WIN_DUMP_FIELD(NumberProcessors); i++) { |
| 399 | if (cpu_memory_rw_debug(first_cpu, saved_ctx[i].addr, |
| 400 | &saved_ctx[i].ctx, win_dump_ctx_size(x64), 1)) { |
| 401 | warn_report("win-dump: failed to restore CPU #%d context", i); |
| 402 | } |
| 403 | } |
| 404 | } |
| 405 | |
| 406 | bool win_dump_available(Error **errp) |
| 407 | { |
| 408 | VMCoreInfoState *vmci = vmcoreinfo_find(); |
| 409 | g_autofree uint8_t *note = NULL; |
| 410 | Error *local_err = NULL; |
| 411 | WinDumpHeader *h; |
| 412 | uint32_t size; |
| 413 | bool x64 = true; |
| 414 | |
| 415 | if (migration_guest_ram_loading()) { |
| 416 | error_setg(errp, "win-dump: not available during migration"); |
| 417 | return false; |
| 418 | } |
| 419 | |
| 420 | if (!vmci || !vmci->has_vmcoreinfo || |
| 421 | le16_to_cpu(vmci->vmcoreinfo.guest_format) != |
| 422 | FW_CFG_VMCOREINFO_FORMAT_ELF) { |
| 423 | error_setg(errp, "win-dump: no vmcoreinfo note from the guest"); |
| 424 | return false; |
| 425 | } |
| 426 | |
| 427 | size = le32_to_cpu(vmci->vmcoreinfo.size); |
| 428 | if (size != VMCOREINFO_WIN_DUMP_NOTE_SIZE32 && |
| 429 | size != VMCOREINFO_WIN_DUMP_NOTE_SIZE64) { |
| 430 | error_setg(errp, "win-dump: invalid vmcoreinfo note size"); |
| 431 | return false; |
| 432 | } |
| 433 | |
| 434 | note = g_malloc(size); |
| 435 | physical_memory_read(le64_to_cpu(vmci->vmcoreinfo.paddr), note, size); |
| 436 | |
| 437 | h = (void *)(note + VMCOREINFO_ELF_NOTE_HDR_SIZE); |
| 438 | if (!check_header(h, &x64, &local_err)) { |
| 439 | error_propagate(errp, local_err); |
| 440 | return false; |
| 441 | } |
| 442 | |
| 443 | return true; |
| 444 | } |
| 445 | |
| 446 | void create_win_dump(DumpState *s, Error **errp) |
| 447 | { |
| 448 | WinDumpHeader *h = (void *)(s->guest_note + VMCOREINFO_ELF_NOTE_HDR_SIZE); |
| 449 | X86CPU *first_x86_cpu = X86_CPU(first_cpu); |
| 450 | uint64_t saved_cr3 = first_x86_cpu->env.cr[3]; |
| 451 | struct saved_context *saved_ctx = NULL; |
| 452 | Error *local_err = NULL; |
| 453 | bool x64 = true; |
| 454 | size_t hdr_size; |
| 455 | |
| 456 | if (s->guest_note_size != VMCOREINFO_WIN_DUMP_NOTE_SIZE32 && |
| 457 | s->guest_note_size != VMCOREINFO_WIN_DUMP_NOTE_SIZE64) { |
| 458 | error_setg(errp, "win-dump: invalid vmcoreinfo note size"); |
| 459 | return; |
| 460 | } |
| 461 | |
| 462 | if (!check_header(h, &x64, &local_err)) { |
| 463 | error_propagate(errp, local_err); |
| 464 | return; |
| 465 | } |
| 466 | |
| 467 | hdr_size = x64 ? sizeof(WinDumpHeader64) : sizeof(WinDumpHeader32); |
| 468 | |
| 469 | /* |
| 470 | * Further access to kernel structures by virtual addresses |
| 471 | * should be made from system context. |
| 472 | */ |
| 473 | |
| 474 | first_x86_cpu->env.cr[3] = WIN_DUMP_FIELD(DirectoryTableBase); |
| 475 | |
| 476 | check_kdbg(h, x64, &local_err); |
| 477 | if (local_err) { |
| 478 | error_propagate(errp, local_err); |
| 479 | goto out_cr3; |
| 480 | } |
| 481 | |
| 482 | patch_header(h, x64); |
| 483 | |
| 484 | saved_ctx = g_new(struct saved_context, WIN_DUMP_FIELD(NumberProcessors)); |
| 485 | |
| 486 | /* |
| 487 | * Always patch context because there is no way |
| 488 | * to determine if the system-saved context is valid |
| 489 | */ |
| 490 | |
| 491 | patch_and_save_context(h, x64, saved_ctx, &local_err); |
| 492 | if (local_err) { |
| 493 | error_propagate(errp, local_err); |
| 494 | goto out_free; |
| 495 | } |
| 496 | |
| 497 | s->total_size = WIN_DUMP_FIELD(RequiredDumpSpace); |
| 498 | |
| 499 | s->written_size = qemu_write_full(s->fd, h, hdr_size); |
| 500 | if (s->written_size != hdr_size) { |
| 501 | error_setg_errno(errp, errno, "win-dump: failed to write header"); |
| 502 | goto out_restore; |
| 503 | } |
| 504 | |
| 505 | write_runs(s, h, x64, &local_err); |
| 506 | if (local_err) { |
| 507 | error_propagate(errp, local_err); |
| 508 | goto out_restore; |
| 509 | } |
| 510 | |
| 511 | out_restore: |
| 512 | restore_context(h, x64, saved_ctx); |
| 513 | out_free: |
| 514 | g_free(saved_ctx); |
| 515 | out_cr3: |
| 516 | first_x86_cpu->env.cr[3] = saved_cr3; |
| 517 | } |