diff options
| -rw-r--r-- | Doc/c-api/init.rst | 38 | ||||
| -rw-r--r-- | Include/sysmodule.h | 1 | ||||
| -rw-r--r-- | Misc/NEWS | 5 | ||||
| -rw-r--r-- | Python/sysmodule.c | 10 |
4 files changed, 47 insertions, 7 deletions
diff --git a/Doc/c-api/init.rst b/Doc/c-api/init.rst index 643628e..71e73b0 100644 --- a/Doc/c-api/init.rst +++ b/Doc/c-api/init.rst @@ -22,6 +22,7 @@ Initialization, Finalization, and Threads module: sys triple: module; search; path single: PySys_SetArgv() + single: PySys_SetArgvEx() single: Py_Finalize() Initialize the Python interpreter. In an application embedding Python, this @@ -31,7 +32,7 @@ Initialization, Finalization, and Threads the table of loaded modules (``sys.modules``), and creates the fundamental modules :mod:`builtins`, :mod:`__main__` and :mod:`sys`. It also initializes the module search path (``sys.path``). It does not set ``sys.argv``; use - :cfunc:`PySys_SetArgv` for that. This is a no-op when called for a second time + :cfunc:`PySys_SetArgvEx` for that. This is a no-op when called for a second time (without calling :cfunc:`Py_Finalize` first). There is no return value; it is a fatal error if the initialization fails. @@ -337,7 +338,7 @@ Initialization, Finalization, and Threads ``sys.version``. -.. cfunction:: void PySys_SetArgv(int argc, wchar_t **argv) +.. cfunction:: void PySys_SetArgvEx(int argc, wchar_t **argv, int updatepath) .. index:: single: main() @@ -352,14 +353,41 @@ Initialization, Finalization, and Threads string. If this function fails to initialize :data:`sys.argv`, a fatal condition is signalled using :cfunc:`Py_FatalError`. - This function also prepends the executed script's path to :data:`sys.path`. - If no script is executed (in the case of calling ``python -c`` or just the - interactive interpreter), the empty string is used instead. + If *updatepath* is zero, this is all the function does. If *updatepath* + is non-zero, the function also modifies :data:`sys.path` according to the + following algorithm: + + - If the name of an existing script is passed in ``argv[0]``, the absolute + path of the directory where the script is located is prepended to + :data:`sys.path`. + - Otherwise (that is, if *argc* is 0 or ``argv[0]`` doesn't point + to an existing file name), an empty string is prepended to + :data:`sys.path`, which is the same as prepending the current working + directory (``"."``). + + .. note:: + It is recommended that applications embedding the Python interpreter + for purposes other than executing a single script pass 0 as *updatepath*, + and update :data:`sys.path` themselves if desired. + See `CVE-2008-5983 <http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-5983>`_. + + On versions before 3.1.3, you can achieve the same effect by manually + popping the first :data:`sys.path` element after having called + :cfunc:`PySys_SetArgv`, for example using:: + + PyRun_SimpleString("import sys; sys.path.pop(0)\n"); + + .. versionadded:: 3.1.3 .. XXX impl. doesn't seem consistent in allowing 0/NULL for the params; check w/ Guido. +.. cfunction:: void PySys_SetArgv(int argc, wchar_t **argv) + + This function works like :cfunc:`PySys_SetArgv` with *updatepath* set to 1. + + .. cfunction:: void Py_SetPythonHome(wchar_t *home) Set the default "home" directory, that is, the location of the standard diff --git a/Include/sysmodule.h b/Include/sysmodule.h index 3a3bf3e..786d46a 100644 --- a/Include/sysmodule.h +++ b/Include/sysmodule.h @@ -10,6 +10,7 @@ extern "C" { PyAPI_FUNC(PyObject *) PySys_GetObject(const char *); PyAPI_FUNC(int) PySys_SetObject(const char *, PyObject *); PyAPI_FUNC(void) PySys_SetArgv(int, wchar_t **); +PyAPI_FUNC(void) PySys_SetArgvEx(int, wchar_t **, int); PyAPI_FUNC(void) PySys_SetPath(const wchar_t *); PyAPI_FUNC(void) PySys_WriteStdout(const char *format, ...) @@ -334,6 +334,11 @@ Core and Builtins C-API ----- +- Issue #5753: A new C API function, :cfunc:`PySys_SetArgvEx`, allows + embedders of the interpreter to set sys.argv without also modifying + sys.path. This helps fix `CVE-2008-5983 + <http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-5983>`_. + - Add PyArg_ValidateKeywordArguments, which checks if all keyword arguments are strings in an efficient manner. diff --git a/Python/sysmodule.c b/Python/sysmodule.c index ce06d7d..77b120f 100644 --- a/Python/sysmodule.c +++ b/Python/sysmodule.c @@ -1668,7 +1668,7 @@ _wrealpath(const wchar_t *path, wchar_t *resolved_path) #endif void -PySys_SetArgv(int argc, wchar_t **argv) +PySys_SetArgvEx(int argc, wchar_t **argv, int updatepath) { #if defined(HAVE_REALPATH) wchar_t fullpath[MAXPATHLEN]; @@ -1681,7 +1681,7 @@ PySys_SetArgv(int argc, wchar_t **argv) Py_FatalError("no mem for sys.argv"); if (PySys_SetObject("argv", av) != 0) Py_FatalError("can't assign sys.argv"); - if (path != NULL) { + if (updatepath && path != NULL) { wchar_t *argv0 = argv[0]; wchar_t *p = NULL; Py_ssize_t n = 0; @@ -1768,6 +1768,12 @@ PySys_SetArgv(int argc, wchar_t **argv) Py_DECREF(av); } +void +PySys_SetArgv(int argc, wchar_t **argv) +{ + PySys_SetArgvEx(argc, argv, 1); +} + /* Reimplementation of PyFile_WriteString() no calling indirectly PyErr_CheckSignals(): avoid the call to PyObject_Str(). */ |