diff --git a/Modules/_remote_debugging_module.c b/Modules/_remote_debugging_module.c index 0b6b9d7f301a98..4fe94d43924231 100644 --- a/Modules/_remote_debugging_module.c +++ b/Modules/_remote_debugging_module.c @@ -28,6 +28,7 @@ // issues. #include #include +#include #include #include #include @@ -807,7 +808,7 @@ static int append_awaited_by(RemoteUnwinderObject *unwinder, unsigned long tid, #define set_exception_cause(unwinder, exc_type, message) \ do { \ assert(PyErr_Occurred() && "function returned -1 without setting exception"); \ - if (unwinder->debug) { \ + if (unwinder->debug && !_Py_RemoteDebug_HasPermissionError()) { \ _set_debug_exception_cause(exc_type, message); \ } \ } while (0) @@ -1246,26 +1247,21 @@ read_py_long( return -1; } - // If the long object has inline digits, use them directly - digit *digits; - if (size <= _PY_NSMALLNEGINTS + _PY_NSMALLPOSINTS) { - // For small integers, digits are inline in the long_value.ob_digit array - digits = (digit *)PyMem_RawMalloc(size * sizeof(digit)); - if (!digits) { - PyErr_NoMemory(); - set_exception_cause(unwinder, PyExc_MemoryError, "Failed to allocate digits for small PyLong"); - return -1; - } - memcpy(digits, long_obj + unwinder->debug_offsets.long_object.ob_digit, size * sizeof(digit)); - } else { - // For larger integers, we need to read the digits separately - digits = (digit *)PyMem_RawMalloc(size * sizeof(digit)); - if (!digits) { - PyErr_NoMemory(); - set_exception_cause(unwinder, PyExc_MemoryError, "Failed to allocate digits for large PyLong"); - return -1; - } + // Calculate how many digits fit inline in our local buffer + Py_ssize_t ob_digit_offset = unwinder->debug_offsets.long_object.ob_digit; + Py_ssize_t inline_digits_space = SIZEOF_LONG_OBJ - ob_digit_offset; + Py_ssize_t max_inline_digits = inline_digits_space / (Py_ssize_t)sizeof(digit); + digit *digits = (digit *)PyMem_RawMalloc(size * sizeof(digit)); + if (!digits) { + PyErr_NoMemory(); + set_exception_cause(unwinder, PyExc_MemoryError, "Failed to allocate digits for PyLong"); + return -1; + } + + if (size <= max_inline_digits && size <= _PY_NSMALLNEGINTS + _PY_NSMALLPOSINTS) { + memcpy(digits, long_obj + ob_digit_offset, size * sizeof(digit)); + } else { bytes_read = _Py_RemoteDebug_PagedReadRemoteMemory( &unwinder->handle, address + (uintptr_t)unwinder->debug_offsets.long_object.ob_digit, @@ -1278,19 +1274,34 @@ read_py_long( } } - long long value = 0; + unsigned long limit = negative + ? (unsigned long)LONG_MAX + 1UL + : (unsigned long)LONG_MAX; + unsigned long value = 0; - // In theory this can overflow, but because of llvm/llvm-project#16778 - // we can't use __builtin_mul_overflow because it fails to link with - // __muloti4 on aarch64. In practice this is fine because all we're - // testing here are task numbers that would fit in a single byte. - for (Py_ssize_t i = 0; i < size; ++i) { - long long factor = digits[i] * (1UL << (Py_ssize_t)(shift * i)); - value += factor; + for (Py_ssize_t i = size; i-- > 0;) { + if (digits[i] >= PyLong_BASE) { + PyErr_Format(PyExc_RuntimeError, + "Invalid PyLong digit: %u (base %u)", digits[i], PyLong_BASE); + set_exception_cause(unwinder, PyExc_RuntimeError, + "Invalid PyLong digit (corrupted remote memory)"); + goto error; + } + if (value > ((limit - (unsigned long)digits[i]) >> shift)) { + PyErr_SetString(PyExc_OverflowError, + "Remote PyLong value does not fit in C long"); + set_exception_cause(unwinder, PyExc_OverflowError, + "Remote PyLong value is too large"); + goto error; + } + value = (value << shift) | (unsigned long)digits[i]; } PyMem_RawFree(digits); if (negative) { - value *= -1; + if (value == (unsigned long)LONG_MAX + 1UL) { + return LONG_MIN; + } + return -(long)value; } return (long)value; error: @@ -1312,32 +1323,35 @@ _Py_RemoteDebug_GetAsyncioDebugAddress(proc_handle_t* handle) // On Windows, search for asyncio debug in executable or DLL address = search_windows_map_for_section(handle, "AsyncioD", L"_asyncio", NULL); if (address == 0) { - // Error out: 'python' substring covers both executable and DLL - PyObject *exc = PyErr_GetRaisedException(); - PyErr_SetString(PyExc_RuntimeError, "Failed to find the AsyncioDebug section in the process."); - _PyErr_ChainExceptions1(exc); + if (!_Py_RemoteDebug_HasPermissionError()) { + PyObject *exc = PyErr_GetRaisedException(); + PyErr_SetString(PyExc_RuntimeError, "Failed to find the AsyncioDebug section in the process."); + _PyErr_ChainExceptions1(exc); + } } #elif defined(__linux__) // On Linux, search for asyncio debug in executable or DLL address = search_linux_map_for_section(handle, "AsyncioDebug", "_asyncio.cpython", NULL); if (address == 0) { - // Error out: 'python' substring covers both executable and DLL - PyObject *exc = PyErr_GetRaisedException(); - PyErr_SetString(PyExc_RuntimeError, "Failed to find the AsyncioDebug section in the process."); - _PyErr_ChainExceptions1(exc); + if (!_Py_RemoteDebug_HasPermissionError()) { + PyObject *exc = PyErr_GetRaisedException(); + PyErr_SetString(PyExc_RuntimeError, "Failed to find the AsyncioDebug section in the process."); + _PyErr_ChainExceptions1(exc); + } } #elif defined(__APPLE__) && TARGET_OS_OSX // On macOS, try libpython first, then fall back to python address = search_map_for_section(handle, "AsyncioDebug", "_asyncio.cpython", NULL); - if (address == 0) { + if (address == 0 && !_Py_RemoteDebug_HasPermissionError()) { PyErr_Clear(); address = search_map_for_section(handle, "AsyncioDebug", "_asyncio.cpython", NULL); } if (address == 0) { - // Error out: 'python' substring covers both executable and DLL - PyObject *exc = PyErr_GetRaisedException(); - PyErr_SetString(PyExc_RuntimeError, "Failed to find the AsyncioDebug section in the process."); - _PyErr_ChainExceptions1(exc); + if (!_Py_RemoteDebug_HasPermissionError()) { + PyObject *exc = PyErr_GetRaisedException(); + PyErr_SetString(PyExc_RuntimeError, "Failed to find the AsyncioDebug section in the process."); + _PyErr_ChainExceptions1(exc); + } } #else Py_UNREACHABLE(); @@ -1418,7 +1432,7 @@ parse_task_name( if ((GET_MEMBER(unsigned long, type_obj, unwinder->debug_offsets.type_object.tp_flags) & Py_TPFLAGS_LONG_SUBCLASS)) { long res = read_py_long(unwinder, task_name_addr); - if (res == -1) { + if (res == -1 && PyErr_Occurred()) { set_exception_cause(unwinder, PyExc_RuntimeError, "Task name PyLong parsing failed"); return NULL; } @@ -3124,6 +3138,9 @@ _remote_debugging_RemoteUnwinder___init___impl(RemoteUnwinderObject *self, return -1; } if (async_debug_result < 0) { + if (_Py_RemoteDebug_HasPermissionError()) { + return -1; + } PyErr_Clear(); memset(&self->async_debug_offsets, 0, sizeof(self->async_debug_offsets)); self->async_debug_offsets_available = 0; diff --git a/Python/remote_debug.h b/Python/remote_debug.h index bacba2ed5f000f..ed0c4e2c85c37d 100644 --- a/Python/remote_debug.h +++ b/Python/remote_debug.h @@ -92,7 +92,7 @@ _Py_RemoteDebug_HasPermissionError(void) #define _set_debug_exception_cause(exception, format, ...) \ do { \ - if (!PyErr_ExceptionMatches(PyExc_PermissionError)) { \ + if (!_Py_RemoteDebug_HasPermissionError()) { \ PyThreadState *tstate = _PyThreadState_GET(); \ if (!_PyErr_Occurred(tstate)) { \ _PyErr_Format(tstate, exception, format, ##__VA_ARGS__); \ @@ -102,6 +102,20 @@ _Py_RemoteDebug_HasPermissionError(void) } \ } while (0) +#define _set_debug_oserror_from_errno(err, format, ...) \ + do { \ + errno = (err); \ + PyErr_SetFromErrno(PyExc_OSError); \ + _set_debug_exception_cause(PyExc_OSError, format, ##__VA_ARGS__); \ + } while (0) + +#define _set_debug_oserror_from_errno_with_filename(err, filename, format, ...) \ + do { \ + errno = (err); \ + PyErr_SetFromErrnoWithFilename(PyExc_OSError, filename); \ + _set_debug_exception_cause(PyExc_OSError, format, ##__VA_ARGS__); \ + } while (0) + static inline size_t get_page_size(void) { size_t page_size = 0; @@ -192,6 +206,20 @@ static mach_port_t pid_to_task(pid_t pid); // Initialize the process handle static int _Py_RemoteDebug_InitProcHandle(proc_handle_t *handle, pid_t pid) { + handle->pid = 0; +#if defined(__APPLE__) && defined(TARGET_OS_OSX) && TARGET_OS_OSX + handle->task = 0; +#elif defined(MS_WINDOWS) + handle->hProcess = NULL; +#elif defined(__linux__) + handle->memfd = -1; +#endif + handle->page_size = get_page_size(); + for (int i = 0; i < MAX_PAGES; i++) { + handle->pages[i].data = NULL; + handle->pages[i].valid = 0; + } + handle->pid = pid; #if defined(__APPLE__) && defined(TARGET_OS_OSX) && TARGET_OS_OSX handle->task = pid_to_task(handle->pid); @@ -204,18 +232,12 @@ _Py_RemoteDebug_InitProcHandle(proc_handle_t *handle, pid_t pid) { PROCESS_VM_READ | PROCESS_VM_WRITE | PROCESS_VM_OPERATION | PROCESS_QUERY_INFORMATION, FALSE, pid); if (handle->hProcess == NULL) { - PyErr_SetFromWindowsErr(0); + DWORD error = GetLastError(); + PyErr_SetFromWindowsErr(error); _set_debug_exception_cause(PyExc_RuntimeError, "Failed to initialize Windows process handle"); return -1; } -#elif defined(__linux__) - handle->memfd = -1; #endif - handle->page_size = get_page_size(); - for (int i = 0; i < MAX_PAGES; i++) { - handle->pages[i].data = NULL; - handle->pages[i].valid = 0; - } return 0; } @@ -380,17 +402,19 @@ return_section_address_fat( size_t cpu_size = sizeof(cpu), abi64_size = sizeof(is_abi64); if (sysctlbyname("hw.cputype", &cpu, &cpu_size, NULL, 0) != 0) { - PyErr_Format(PyExc_OSError, + int err = errno; + _set_debug_oserror_from_errno(err, "Failed to determine CPU type via sysctlbyname " "for fat binary analysis at 0x%lx: %s", - base, strerror(errno)); + base, strerror(err)); return 0; } if (sysctlbyname("hw.cpu64bit_capable", &is_abi64, &abi64_size, NULL, 0) != 0) { - PyErr_Format(PyExc_OSError, + int err = errno; + _set_debug_oserror_from_errno(err, "Failed to determine CPU ABI capability via sysctlbyname " "for fat binary analysis at 0x%lx: %s", - base, strerror(errno)); + base, strerror(err)); return 0; } @@ -443,26 +467,29 @@ search_section_in_file(const char* secname, char* path, uintptr_t base, mach_vm_ { int fd = open(path, O_RDONLY); if (fd == -1) { - PyErr_Format(PyExc_OSError, + int err = errno; + _set_debug_oserror_from_errno_with_filename(err, path, "Cannot open binary file '%s' for section '%s' search: %s", - path, secname, strerror(errno)); + path, secname, strerror(err)); return 0; } struct stat fs; if (fstat(fd, &fs) == -1) { - PyErr_Format(PyExc_OSError, + int err = errno; + _set_debug_oserror_from_errno_with_filename(err, path, "Cannot get file size for binary '%s' during section '%s' search: %s", - path, secname, strerror(errno)); + path, secname, strerror(err)); close(fd); return 0; } void* map = mmap(0, fs.st_size, PROT_READ, MAP_SHARED, fd, 0); if (map == MAP_FAILED) { - PyErr_Format(PyExc_OSError, + int err = errno; + _set_debug_oserror_from_errno_with_filename(err, path, "Cannot memory map binary file '%s' (size: %lld bytes) for section '%s' search: %s", - path, (long long)fs.st_size, secname, strerror(errno)); + path, (long long)fs.st_size, secname, strerror(err)); close(fd); return 0; } @@ -491,15 +518,21 @@ search_section_in_file(const char* secname, char* path, uintptr_t base, mach_vm_ } if (munmap(map, fs.st_size) != 0) { - PyErr_Format(PyExc_OSError, - "Failed to unmap binary file '%s' (size: %lld bytes): %s", - path, (long long)fs.st_size, strerror(errno)); + if (!PyErr_Occurred()) { + int err = errno; + _set_debug_oserror_from_errno_with_filename(err, path, + "Failed to unmap binary file '%s' (size: %lld bytes): %s", + path, (long long)fs.st_size, strerror(err)); + } result = 0; } if (close(fd) != 0) { - PyErr_Format(PyExc_OSError, - "Failed to close binary file '%s': %s", - path, strerror(errno)); + if (!PyErr_Occurred()) { + int err = errno; + _set_debug_oserror_from_errno_with_filename(err, path, + "Failed to close binary file '%s': %s", + path, strerror(err)); + } result = 0; } return result; @@ -544,14 +577,15 @@ search_map_for_section(proc_handle_t *handle, const char* secname, const char* s char map_filename[MAXPATHLEN + 1]; - while (mach_vm_region( - proc_ref, - &address, - &size, - VM_REGION_BASIC_INFO_64, - (vm_region_info_t)®ion_info, - &count, - &object_name) == KERN_SUCCESS) + kern_return_t kr; + while ((kr = mach_vm_region( + proc_ref, + &address, + &size, + VM_REGION_BASIC_INFO_64, + (vm_region_info_t)®ion_info, + &count, + &object_name)) == KERN_SUCCESS) { if ((region_info.protection & VM_PROT_READ) == 0 @@ -575,18 +609,32 @@ search_map_for_section(proc_handle_t *handle, const char* secname, const char* s } if (strncmp(filename, substr, strlen(substr)) == 0) { + PyErr_Clear(); uintptr_t result = search_section_in_file( secname, map_filename, address, size, proc_ref); - if (result != 0 - && (validator == NULL || validator(handle, result))) - { - return result; + if (result != 0) { + if (validator == NULL || validator(handle, result)) { + return result; + } + if (_Py_RemoteDebug_HasPermissionError()) { + return 0; + } + } + else if (_Py_RemoteDebug_HasPermissionError()) { + return 0; } } address += size; } + if (kr != KERN_INVALID_ADDRESS && !PyErr_Occurred()) { + PyErr_Format(PyExc_RuntimeError, + "mach_vm_region failed while searching PID %d for section '%s' " + "(kern_return_t: %d)", + handle->pid, secname, kr); + } + return 0; } @@ -609,25 +657,29 @@ search_elf_file_for_section( int fd = open(elf_file, O_RDONLY); if (fd < 0) { - PyErr_Format(PyExc_OSError, + int err = errno; + _set_debug_oserror_from_errno_with_filename(err, elf_file, "Cannot open ELF file '%s' for section '%s' search: %s", - elf_file, secname, strerror(errno)); + elf_file, secname, strerror(err)); goto exit; } struct stat file_stats; if (fstat(fd, &file_stats) != 0) { - PyErr_Format(PyExc_OSError, + int err = errno; + _set_debug_oserror_from_errno_with_filename(err, elf_file, "Cannot get file size for ELF file '%s' during section '%s' search: %s", - elf_file, secname, strerror(errno)); + elf_file, secname, strerror(err)); goto exit; } file_memory = mmap(NULL, file_stats.st_size, PROT_READ, MAP_PRIVATE, fd, 0); if (file_memory == MAP_FAILED) { - PyErr_Format(PyExc_OSError, + int err = errno; + _set_debug_oserror_from_errno_with_filename(err, elf_file, "Cannot memory map ELF file '%s' (size: %lld bytes) for section '%s' search: %s", - elf_file, (long long)file_stats.st_size, secname, strerror(errno)); + elf_file, (long long)file_stats.st_size, secname, strerror(err)); + file_memory = NULL; goto exit; } @@ -684,12 +736,23 @@ search_elf_file_for_section( exit: if (file_memory != NULL) { - munmap(file_memory, file_stats.st_size); + if (munmap(file_memory, file_stats.st_size) != 0) { + if (!PyErr_Occurred()) { + int err = errno; + _set_debug_oserror_from_errno_with_filename(err, elf_file, + "Failed to unmap ELF file '%s' (size: %lld bytes): %s", + elf_file, (long long)file_stats.st_size, strerror(err)); + } + result = 0; + } } if (fd >= 0 && close(fd) != 0) { - PyErr_Format(PyExc_OSError, - "Failed to close ELF file '%s': %s", - elf_file, strerror(errno)); + if (!PyErr_Occurred()) { + int err = errno; + _set_debug_oserror_from_errno_with_filename(err, elf_file, + "Failed to close ELF file '%s': %s", + elf_file, strerror(err)); + } result = 0; } return result; @@ -804,9 +867,10 @@ search_linux_map_for_section(proc_handle_t *handle, const char* secname, const c FILE* maps_file = fopen(maps_file_path, "r"); if (maps_file == NULL) { - PyErr_Format(PyExc_OSError, + int err = errno; + _set_debug_oserror_from_errno_with_filename(err, maps_file_path, "Cannot open process memory map file '%s' for PID %d section search: %s", - maps_file_path, handle->pid, strerror(errno)); + maps_file_path, handle->pid, strerror(err)); return 0; } @@ -908,11 +972,21 @@ search_linux_map_for_section(proc_handle_t *handle, const char* secname, const c } } + if (retval == 0 && !PyErr_Occurred() && ferror(maps_file)) { + int err = errno; + _set_debug_oserror_from_errno_with_filename(err, maps_file_path, + "Failed to read process map file '%s' for PID %d section search: %s", + maps_file_path, handle->pid, strerror(err)); + } + PyMem_Free(line); if (fclose(maps_file) != 0) { - PyErr_Format(PyExc_OSError, - "Failed to close process map file '%s': %s", - maps_file_path, strerror(errno)); + if (!PyErr_Occurred()) { + int err = errno; + _set_debug_oserror_from_errno_with_filename(err, maps_file_path, + "Failed to close process map file '%s': %s", + maps_file_path, strerror(err)); + } retval = 0; } @@ -924,12 +998,22 @@ search_linux_map_for_section(proc_handle_t *handle, const char* secname, const c #ifdef MS_WINDOWS +static int +is_process_alive(HANDLE hProcess) +{ + DWORD exitCode; + if (GetExitCodeProcess(hProcess, &exitCode)) { + return exitCode == STILL_ACTIVE; + } + return 0; +} + static void* analyze_pe(const wchar_t* mod_path, BYTE* remote_base, const char* secname) { HANDLE hFile = CreateFileW(mod_path, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL); if (hFile == INVALID_HANDLE_VALUE) { - PyErr_SetFromWindowsErr(0); DWORD error = GetLastError(); - PyErr_Format(PyExc_OSError, + PyErr_SetFromWindowsErr(error); + _set_debug_exception_cause(PyExc_OSError, "Cannot open PE file for section '%s' analysis (error %lu)", secname, error); return NULL; @@ -937,9 +1021,9 @@ static void* analyze_pe(const wchar_t* mod_path, BYTE* remote_base, const char* HANDLE hMap = CreateFileMapping(hFile, NULL, PAGE_READONLY, 0, 0, 0); if (!hMap) { - PyErr_SetFromWindowsErr(0); DWORD error = GetLastError(); - PyErr_Format(PyExc_OSError, + PyErr_SetFromWindowsErr(error); + _set_debug_exception_cause(PyExc_OSError, "Cannot create file mapping for PE file section '%s' analysis (error %lu)", secname, error); CloseHandle(hFile); @@ -948,9 +1032,9 @@ static void* analyze_pe(const wchar_t* mod_path, BYTE* remote_base, const char* BYTE* mapView = (BYTE*)MapViewOfFile(hMap, FILE_MAP_READ, 0, 0, 0); if (!mapView) { - PyErr_SetFromWindowsErr(0); DWORD error = GetLastError(); - PyErr_Format(PyExc_OSError, + PyErr_SetFromWindowsErr(error); + _set_debug_exception_cause(PyExc_OSError, "Cannot map view of PE file for section '%s' analysis (error %lu)", secname, error); CloseHandle(hMap); @@ -1008,9 +1092,9 @@ search_windows_map_for_section(proc_handle_t* handle, const char* secname, const } while (hProcSnap == INVALID_HANDLE_VALUE && GetLastError() == ERROR_BAD_LENGTH); if (hProcSnap == INVALID_HANDLE_VALUE) { - PyErr_SetFromWindowsErr(0); DWORD error = GetLastError(); - PyErr_Format(PyExc_PermissionError, + PyErr_SetFromWindowsErr(error); + _set_debug_exception_cause(PyExc_OSError, "Unable to create module snapshot for PID %d section '%s' " "search (error %lu). Check permissions or PID validity", handle->pid, secname, error); @@ -1021,17 +1105,46 @@ search_windows_map_for_section(proc_handle_t* handle, const char* secname, const moduleEntry.dwSize = sizeof(moduleEntry); void* runtime_addr = NULL; - for (BOOL hasModule = Module32FirstW(hProcSnap, &moduleEntry); hasModule; hasModule = Module32NextW(hProcSnap, &moduleEntry)) { + if (!Module32FirstW(hProcSnap, &moduleEntry)) { + DWORD error = GetLastError(); + PyErr_SetFromWindowsErr(error); + _set_debug_exception_cause(PyExc_OSError, + "Unable to enumerate modules for PID %d section '%s' " + "search (error %lu)", + handle->pid, secname, error); + CloseHandle(hProcSnap); + return 0; + } + + do { // Look for either python executable or DLL if (wcsstr(moduleEntry.szModule, substr)) { + PyErr_Clear(); void *candidate = analyze_pe(moduleEntry.szExePath, moduleEntry.modBaseAddr, secname); - if (candidate != NULL - && (validator == NULL || validator(handle, (uintptr_t)candidate))) - { - runtime_addr = candidate; + if (candidate != NULL) { + if (validator == NULL || validator(handle, (uintptr_t)candidate)) { + runtime_addr = candidate; + break; + } + if (_Py_RemoteDebug_HasPermissionError()) { + break; + } + } + else if (_Py_RemoteDebug_HasPermissionError()) { break; } } + } while (Module32NextW(hProcSnap, &moduleEntry)); + + if (runtime_addr == NULL && !PyErr_Occurred()) { + DWORD error = GetLastError(); + if (error != ERROR_NO_MORE_FILES) { + PyErr_SetFromWindowsErr(error); + _set_debug_exception_cause(PyExc_OSError, + "Module enumeration failed for PID %d section '%s' " + "search (error %lu)", + handle->pid, secname, error); + } } CloseHandle(hProcSnap); @@ -1052,12 +1165,14 @@ _Py_RemoteDebug_GetPyRuntimeAddress(proc_handle_t* handle) address = search_windows_map_for_section(handle, "PyRuntime", L"python", _Py_RemoteDebug_ValidatePyRuntimeCookie); if (address == 0) { - // Error out: 'python' substring covers both executable and DLL - PyObject *exc = PyErr_GetRaisedException(); - PyErr_Format(PyExc_RuntimeError, - "Failed to find the PyRuntime section in process %d on Windows platform", - handle->pid); - _PyErr_ChainExceptions1(exc); + if (!_Py_RemoteDebug_HasPermissionError()) { + // Error out: 'python' substring covers both executable and DLL + PyObject *exc = PyErr_GetRaisedException(); + PyErr_Format(PyExc_RuntimeError, + "Failed to find the PyRuntime section in process %d on Windows platform", + handle->pid); + _PyErr_ChainExceptions1(exc); + } } #elif defined(__linux__) // On Linux, search for 'python' in executable or DLL @@ -1080,17 +1195,19 @@ _Py_RemoteDebug_GetPyRuntimeAddress(proc_handle_t* handle) PyErr_Clear(); address = search_map_for_section(handle, "PyRuntime", *candidate, _Py_RemoteDebug_ValidatePyRuntimeCookie); - if (address != 0) { + if (address != 0 || _Py_RemoteDebug_HasPermissionError()) { break; } } if (address == 0) { - PyObject *exc = PyErr_GetRaisedException(); - PyErr_Format(PyExc_RuntimeError, - "Failed to find the PyRuntime section in process %d " - "on macOS platform (tried both libpython and python)", - handle->pid); - _PyErr_ChainExceptions1(exc); + if (!_Py_RemoteDebug_HasPermissionError()) { + PyObject *exc = PyErr_GetRaisedException(); + PyErr_Format(PyExc_RuntimeError, + "Failed to find the PyRuntime section in process %d " + "on macOS platform (tried both libpython and python)", + handle->pid); + _PyErr_ChainExceptions1(exc); + } } #else Py_UNREACHABLE(); @@ -1109,9 +1226,9 @@ open_proc_mem_fd(proc_handle_t *handle) handle->memfd = open(mem_file_path, O_RDWR); if (handle->memfd == -1) { - PyErr_SetFromErrno(PyExc_OSError); - _set_debug_exception_cause(PyExc_OSError, - "failed to open file %s: %s", mem_file_path, strerror(errno)); + int err = errno; + _set_debug_oserror_from_errno_with_filename(err, mem_file_path, + "failed to open file %s: %s", mem_file_path, strerror(err)); return -1; } return 0; @@ -1122,6 +1239,9 @@ open_proc_mem_fd(proc_handle_t *handle) static int read_remote_memory_fallback(proc_handle_t *handle, uintptr_t remote_address, size_t len, void* dst) { + if (len == 0) { + return 0; + } if (handle->memfd == -1) { if (open_proc_mem_fd(handle) < 0) { return -1; @@ -1139,14 +1259,23 @@ read_remote_memory_fallback(proc_handle_t *handle, uintptr_t remote_address, siz read_bytes = preadv(handle->memfd, local, 1, offset); if (read_bytes < 0) { + int err = errno; + errno = err; PyErr_SetFromErrno(PyExc_OSError); _set_debug_exception_cause(PyExc_OSError, "preadv failed for PID %d at address 0x%lx " "(size %zu, partial read %zd bytes): %s", - handle->pid, remote_address + result, len - result, result, strerror(errno)); + handle->pid, remote_address + result, len - result, result, strerror(err)); return -1; } + if (read_bytes == 0) { + PyErr_Format(PyExc_OSError, + "preadv returned 0 bytes for PID %d at address 0x%lx " + "(size %zu, partial read %zd bytes)", + handle->pid, remote_address + result, len - result, result); + return -1; + } result += read_bytes; } while ((size_t)read_bytes != local[0].iov_len); return 0; @@ -1158,19 +1287,36 @@ read_remote_memory_fallback(proc_handle_t *handle, uintptr_t remote_address, siz static int _Py_RemoteDebug_ReadRemoteMemory(proc_handle_t *handle, uintptr_t remote_address, size_t len, void* dst) { + if (len == 0) { + return 0; + } #ifdef MS_WINDOWS SIZE_T read_bytes = 0; SIZE_T result = 0; do { if (!ReadProcessMemory(handle->hProcess, (LPCVOID)(remote_address + result), (char*)dst + result, len - result, &read_bytes)) { - PyErr_SetFromWindowsErr(0); DWORD error = GetLastError(); + // Check if the process is still alive: we need to be able to tell our caller + // that the process is dead and not just that the read failed. + if (!is_process_alive(handle->hProcess)) { + _set_errno(ESRCH); + PyErr_SetFromErrno(PyExc_OSError); + return -1; + } + PyErr_SetFromWindowsErr(error); _set_debug_exception_cause(PyExc_OSError, "ReadProcessMemory failed for PID %d at address 0x%lx " "(size %zu, partial read %zu bytes): Windows error %lu", handle->pid, remote_address + result, len - result, result, error); return -1; } + if (read_bytes == 0) { + PyErr_Format(PyExc_OSError, + "ReadProcessMemory returned 0 bytes for PID %d at address 0x%lx " + "(size %zu, partial read %zu bytes)", + handle->pid, remote_address + result, len - result, result); + return -1; + } result += read_bytes; } while (result < len); return 0; @@ -1191,28 +1337,40 @@ _Py_RemoteDebug_ReadRemoteMemory(proc_handle_t *handle, uintptr_t remote_address read_bytes = process_vm_readv(handle->pid, local, 1, remote, 1, 0); if (read_bytes < 0) { - if (errno == ENOSYS) { + int err = errno; + if (err == ENOSYS) { return read_remote_memory_fallback(handle, remote_address, len, dst); } + errno = err; PyErr_SetFromErrno(PyExc_OSError); + if (err == ESRCH) { + return -1; + } _set_debug_exception_cause(PyExc_OSError, "process_vm_readv failed for PID %d at address 0x%lx " "(size %zu, partial read %zd bytes): %s", - handle->pid, remote_address + result, len - result, result, strerror(errno)); + handle->pid, remote_address + result, len - result, result, strerror(err)); return -1; } + if (read_bytes == 0) { + PyErr_Format(PyExc_OSError, + "process_vm_readv returned 0 bytes for PID %d at address 0x%lx " + "(size %zu, partial read %zd bytes)", + handle->pid, remote_address + result, len - result, result); + return -1; + } result += read_bytes; } while ((size_t)read_bytes != local[0].iov_len); return 0; #elif defined(__APPLE__) && defined(TARGET_OS_OSX) && TARGET_OS_OSX - Py_ssize_t result = -1; + mach_vm_size_t bytes_read = 0; kern_return_t kr = mach_vm_read_overwrite( handle->task, (mach_vm_address_t)remote_address, len, (mach_vm_address_t)dst, - (mach_vm_size_t*)&result); + &bytes_read); if (kr != KERN_SUCCESS) { switch (kr) { @@ -1236,6 +1394,13 @@ _Py_RemoteDebug_ReadRemoteMemory(proc_handle_t *handle, uintptr_t remote_address } return -1; } + if (bytes_read != (mach_vm_size_t)len) { + PyErr_Format(PyExc_OSError, + "mach_vm_read_overwrite read %llu of %zu bytes for PID %d at " + "address 0x%lx", + (unsigned long long)bytes_read, len, handle->pid, remote_address); + return -1; + } return 0; #else Py_UNREACHABLE(); diff --git a/Python/remote_debugging.c b/Python/remote_debugging.c index 71ffb17ed68b1d..82e58f03966de3 100644 --- a/Python/remote_debugging.c +++ b/Python/remote_debugging.c @@ -30,6 +30,9 @@ read_memory(proc_handle_t *handle, uintptr_t remote_address, size_t len, void* d static int write_memory_fallback(proc_handle_t *handle, uintptr_t remote_address, size_t len, const void* src) { + if (len == 0) { + return 0; + } if (handle->memfd == -1) { if (open_proc_mem_fd(handle) < 0) { return -1; @@ -47,10 +50,19 @@ write_memory_fallback(proc_handle_t *handle, uintptr_t remote_address, size_t le written = pwritev(handle->memfd, local, 1, offset); if (written < 0) { + int err = errno; + errno = err; PyErr_SetFromErrno(PyExc_OSError); return -1; } + if (written == 0) { + PyErr_Format(PyExc_OSError, + "pwritev wrote 0 bytes for PID %d at address 0x%lx " + "(size %zu, partial write %zd bytes)", + handle->pid, remote_address + result, len - result, result); + return -1; + } result += written; } while ((size_t)written != local[0].iov_len); return 0; @@ -60,12 +72,27 @@ write_memory_fallback(proc_handle_t *handle, uintptr_t remote_address, size_t le static int write_memory(proc_handle_t *handle, uintptr_t remote_address, size_t len, const void* src) { + if (len == 0) { + return 0; + } #ifdef MS_WINDOWS SIZE_T written = 0; SIZE_T result = 0; do { if (!WriteProcessMemory(handle->hProcess, (LPVOID)(remote_address + result), (const char*)src + result, len - result, &written)) { - PyErr_SetFromWindowsErr(0); + DWORD error = GetLastError(); + PyErr_SetFromWindowsErr(error); + _set_debug_exception_cause(PyExc_OSError, + "WriteProcessMemory failed for PID %d at address 0x%lx " + "(size %zu, partial write %zu bytes): Windows error %lu", + handle->pid, remote_address + result, len - result, result, error); + return -1; + } + if (written == 0) { + PyErr_Format(PyExc_OSError, + "WriteProcessMemory wrote 0 bytes for PID %d at address 0x%lx " + "(size %zu, partial write %zu bytes)", + handle->pid, remote_address + result, len - result, result); return -1; } result += written; @@ -88,13 +115,26 @@ write_memory(proc_handle_t *handle, uintptr_t remote_address, size_t len, const written = process_vm_writev(handle->pid, local, 1, remote, 1, 0); if (written < 0) { - if (errno == ENOSYS) { + int err = errno; + if (err == ENOSYS) { return write_memory_fallback(handle, remote_address, len, src); } + errno = err; PyErr_SetFromErrno(PyExc_OSError); + _set_debug_exception_cause(PyExc_OSError, + "process_vm_writev failed for PID %d at address 0x%lx " + "(size %zu, partial write %zd bytes): %s", + handle->pid, remote_address + result, len - result, result, strerror(err)); return -1; } + if (written == 0) { + PyErr_Format(PyExc_OSError, + "process_vm_writev wrote 0 bytes for PID %d at address 0x%lx " + "(size %zu, partial write %zd bytes)", + handle->pid, remote_address + result, len - result, result); + return -1; + } result += written; } while ((size_t)written != local[0].iov_len); return 0; @@ -398,4 +438,3 @@ _PySysRemoteDebug_SendExec(int pid, int tid, const char *debugger_script_path) return rc; #endif } -