diff options
Diffstat (limited to 'Python')
| -rw-r--r-- | Python/clinic/sysmodule.c.h | 55 | ||||
| -rw-r--r-- | Python/initconfig.c | 61 | ||||
| -rw-r--r-- | Python/sysmodule.c | 46 |
3 files changed, 160 insertions, 2 deletions
diff --git a/Python/clinic/sysmodule.c.h b/Python/clinic/sysmodule.c.h index 04c8481149..2a6ad89137 100644 --- a/Python/clinic/sysmodule.c.h +++ b/Python/clinic/sysmodule.c.h @@ -647,6 +647,59 @@ exit: #endif /* defined(USE_MALLOPT) */ +PyDoc_STRVAR(sys_get_int_max_str_digits__doc__, +"get_int_max_str_digits($module, /)\n" +"--\n" +"\n" +"Set the maximum string digits limit for non-binary int<->str conversions."); + +#define SYS_GET_INT_MAX_STR_DIGITS_METHODDEF \ + {"get_int_max_str_digits", (PyCFunction)sys_get_int_max_str_digits, METH_NOARGS, sys_get_int_max_str_digits__doc__}, + +static PyObject * +sys_get_int_max_str_digits_impl(PyObject *module); + +static PyObject * +sys_get_int_max_str_digits(PyObject *module, PyObject *Py_UNUSED(ignored)) +{ + return sys_get_int_max_str_digits_impl(module); +} + +PyDoc_STRVAR(sys_set_int_max_str_digits__doc__, +"set_int_max_str_digits($module, /, maxdigits)\n" +"--\n" +"\n" +"Set the maximum string digits limit for non-binary int<->str conversions."); + +#define SYS_SET_INT_MAX_STR_DIGITS_METHODDEF \ + {"set_int_max_str_digits", (PyCFunction)(void(*)(void))sys_set_int_max_str_digits, METH_FASTCALL|METH_KEYWORDS, sys_set_int_max_str_digits__doc__}, + +static PyObject * +sys_set_int_max_str_digits_impl(PyObject *module, int maxdigits); + +static PyObject * +sys_set_int_max_str_digits(PyObject *module, PyObject *const *args, Py_ssize_t nargs, PyObject *kwnames) +{ + PyObject *return_value = NULL; + static const char * const _keywords[] = {"maxdigits", NULL}; + static _PyArg_Parser _parser = {NULL, _keywords, "set_int_max_str_digits", 0}; + PyObject *argsbuf[1]; + int maxdigits; + + args = _PyArg_UnpackKeywords(args, nargs, NULL, kwnames, &_parser, 1, 1, 0, argsbuf); + if (!args) { + goto exit; + } + maxdigits = _PyLong_AsInt(args[0]); + if (maxdigits == -1 && PyErr_Occurred()) { + goto exit; + } + return_value = sys_set_int_max_str_digits_impl(module, maxdigits); + +exit: + return return_value; +} + PyDoc_STRVAR(sys_getrefcount__doc__, "getrefcount($module, object, /)\n" "--\n" @@ -983,4 +1036,4 @@ sys__deactivate_opcache(PyObject *module, PyObject *Py_UNUSED(ignored)) #ifndef SYS_GETANDROIDAPILEVEL_METHODDEF #define SYS_GETANDROIDAPILEVEL_METHODDEF #endif /* !defined(SYS_GETANDROIDAPILEVEL_METHODDEF) */ -/*[clinic end generated code: output=68c62b9ca317a0c8 input=a9049054013a1b77]*/ +/*[clinic end generated code: output=6230a1e3a4415744 input=a9049054013a1b77]*/ diff --git a/Python/initconfig.c b/Python/initconfig.c index 0341e7baa2..0d2077a657 100644 --- a/Python/initconfig.c +++ b/Python/initconfig.c @@ -3,6 +3,7 @@ #include "pycore_getopt.h" // _PyOS_GetOpt() #include "pycore_initconfig.h" // _PyStatus_OK() #include "pycore_interp.h" // _PyInterpreterState.runtime +#include "pycore_long.h" // _PY_LONG_MAX_STR_DIGITS_THRESHOLD #include "pycore_pathconfig.h" // _Py_path_config #include "pycore_pyerrors.h" // _PyErr_Fetch() #include "pycore_pylifecycle.h" // _Py_PreInitializeFromConfig() @@ -95,6 +96,10 @@ static const char usage_3[] = "\ -X pycache_prefix=PATH: enable writing .pyc files to a parallel tree rooted at the\n\ given directory instead of to the code tree\n\ -X warn_default_encoding: enable opt-in EncodingWarning for 'encoding=None'\n\ + -X int_max_str_digits=number: limit the size of int<->str conversions.\n\ + This helps avoid denial of service attacks when parsing untrusted data.\n\ + The default is sys.int_info.default_max_str_digits. 0 disables.\n\ +\n\ --check-hash-based-pycs always|default|never:\n\ control how Python invalidates hash-based .pyc files\n\ "; @@ -120,6 +125,10 @@ static const char usage_6[] = " to seed the hashes of str and bytes objects. It can also be set to an\n" " integer in the range [0,4294967295] to get hash values with a\n" " predictable seed.\n" +"PYTHONINTMAXSTRDIGITS: limits the maximum digit characters in an int value\n" +" when converting from a string and when converting an int back to a str.\n" +" A value of 0 disables the limit. Conversions to or from bases 2, 4, 8,\n" +" 16, and 32 are never limited.\n" "PYTHONMALLOC: set the Python memory allocators and/or install debug hooks\n" " on Python memory allocators. Use PYTHONMALLOC=debug to install debug\n" " hooks.\n" @@ -721,6 +730,10 @@ _PyConfig_InitCompatConfig(PyConfig *config) #endif } +/* Excluded from public struct PyConfig for backporting reasons. */ +/* default to unconfigured, _PyLong_InitTypes() does the rest */ +int _Py_global_config_int_max_str_digits = -1; + static void config_init_defaults(PyConfig *config) @@ -1757,6 +1770,48 @@ config_init_tracemalloc(PyConfig *config) return _PyStatus_OK(); } +static PyStatus +config_init_int_max_str_digits(PyConfig *config) +{ + int maxdigits; + int valid = 0; + + const char *env = config_get_env(config, "PYTHONINTMAXSTRDIGITS"); + if (env) { + if (!_Py_str_to_int(env, &maxdigits)) { + valid = ((maxdigits == 0) || (maxdigits >= _PY_LONG_MAX_STR_DIGITS_THRESHOLD)); + } + if (!valid) { +#define STRINGIFY(VAL) _STRINGIFY(VAL) +#define _STRINGIFY(VAL) #VAL + return _PyStatus_ERR( + "PYTHONINTMAXSTRDIGITS: invalid limit; must be >= " + STRINGIFY(_PY_LONG_MAX_STR_DIGITS_THRESHOLD) + " or 0 for unlimited."); + } + _Py_global_config_int_max_str_digits = maxdigits; + } + + const wchar_t *xoption = config_get_xoption(config, L"int_max_str_digits"); + if (xoption) { + const wchar_t *sep = wcschr(xoption, L'='); + if (sep) { + if (!config_wstr_to_int(sep + 1, &maxdigits)) { + valid = ((maxdigits == 0) || (maxdigits >= _PY_LONG_MAX_STR_DIGITS_THRESHOLD)); + } + } + if (!valid) { + return _PyStatus_ERR( + "-X int_max_str_digits: invalid limit; must be >= " + STRINGIFY(_PY_LONG_MAX_STR_DIGITS_THRESHOLD) + " or 0 for unlimited."); +#undef _STRINGIFY +#undef STRINGIFY + } + _Py_global_config_int_max_str_digits = maxdigits; + } + return _PyStatus_OK(); +} static PyStatus config_init_pycache_prefix(PyConfig *config) @@ -1808,6 +1863,12 @@ config_read_complex_options(PyConfig *config) return status; } } + if (_Py_global_config_int_max_str_digits < 0) { + status = config_init_int_max_str_digits(config); + if (_PyStatus_EXCEPTION(status)) { + return status; + } + } if (config->pycache_prefix == NULL) { status = config_init_pycache_prefix(config); diff --git a/Python/sysmodule.c b/Python/sysmodule.c index ac49f7867a..1d5a06a6b4 100644 --- a/Python/sysmodule.c +++ b/Python/sysmodule.c @@ -17,6 +17,7 @@ Data members: #include "Python.h" #include "pycore_ceval.h" // _Py_RecursionLimitLowerWaterMark() #include "pycore_initconfig.h" // _PyStatus_EXCEPTION() +#include "pycore_long.h" // _PY_LONG_MAX_STR_DIGITS_THRESHOLD #include "pycore_object.h" // _PyObject_IS_GC() #include "pycore_pathconfig.h" // _PyPathConfig_ComputeSysPath0() #include "pycore_pyerrors.h" // _PyErr_Fetch() @@ -1652,6 +1653,45 @@ sys_mdebug_impl(PyObject *module, int flag) } #endif /* USE_MALLOPT */ + +/*[clinic input] +sys.get_int_max_str_digits + +Set the maximum string digits limit for non-binary int<->str conversions. +[clinic start generated code]*/ + +static PyObject * +sys_get_int_max_str_digits_impl(PyObject *module) +/*[clinic end generated code: output=0042f5e8ae0e8631 input=8dab13e2023e60d5]*/ +{ + PyInterpreterState *interp = _PyInterpreterState_GET(); + return PyLong_FromSsize_t(interp->int_max_str_digits); +} + +/*[clinic input] +sys.set_int_max_str_digits + + maxdigits: int + +Set the maximum string digits limit for non-binary int<->str conversions. +[clinic start generated code]*/ + +static PyObject * +sys_set_int_max_str_digits_impl(PyObject *module, int maxdigits) +/*[clinic end generated code: output=734d4c2511f2a56d input=d7e3f325db6910c5]*/ +{ + PyThreadState *tstate = _PyThreadState_GET(); + if ((!maxdigits) || (maxdigits >= _PY_LONG_MAX_STR_DIGITS_THRESHOLD)) { + tstate->interp->int_max_str_digits = maxdigits; + Py_RETURN_NONE; + } else { + PyErr_Format( + PyExc_ValueError, "maxdigits must be 0 or larger than %d", + _PY_LONG_MAX_STR_DIGITS_THRESHOLD); + return NULL; + } +} + size_t _PySys_GetSizeOf(PyObject *o) { @@ -2027,6 +2067,8 @@ static PyMethodDef sys_methods[] = { SYS_GETANDROIDAPILEVEL_METHODDEF SYS_UNRAISABLEHOOK_METHODDEF SYS__DEACTIVATE_OPCACHE_METHODDEF + SYS_GET_INT_MAX_STR_DIGITS_METHODDEF + SYS_SET_INT_MAX_STR_DIGITS_METHODDEF {NULL, NULL} /* sentinel */ }; @@ -2516,6 +2558,7 @@ static PyStructSequence_Field flags_fields[] = { {"dev_mode", "-X dev"}, {"utf8_mode", "-X utf8"}, {"warn_default_encoding", "-X warn_default_encoding"}, + {"int_max_str_digits", "-X int_max_str_digits"}, {0} }; @@ -2523,7 +2566,7 @@ static PyStructSequence_Desc flags_desc = { "sys.flags", /* name */ flags__doc__, /* doc */ flags_fields, /* fields */ - 16 + 17 }; static int @@ -2563,6 +2606,7 @@ set_flags_from_config(PyInterpreterState *interp, PyObject *flags) SetFlagObj(PyBool_FromLong(config->dev_mode)); SetFlag(preconfig->utf8_mode); SetFlag(config->warn_default_encoding); + SetFlag(_Py_global_config_int_max_str_digits); #undef SetFlagObj #undef SetFlag return 0; |