diff --git a/Lib/test/test_faulthandler.py b/Lib/test/test_faulthandler.py index 4cf98b0491a..3c8c8ebfc51 100644 --- a/Lib/test/test_faulthandler.py +++ b/Lib/test/test_faulthandler.py @@ -69,7 +69,7 @@ class FaultHandlerTests(unittest.TestCase): return output.splitlines() def check_fatal_error(self, code, line_number, name_regex, - filename=None, all_threads=False): + filename=None, all_threads=False, other_regex=None): """ Check that the fault handler for fatal errors is enabled and check the traceback from the child process output. @@ -90,6 +90,8 @@ class FaultHandlerTests(unittest.TestCase): lineno=line_number, name=name_regex, header=re.escape(header)) + if other_regex: + regex += '|' + other_regex output = self.get_output(code, False, filename) output = '\n'.join(output) self.assertRegex(output, regex) @@ -153,7 +155,6 @@ faulthandler._fatal_error(b'xyz') 2, 'xyz') - @unittest.skipIf(True, 'test disabled, see #11393') @unittest.skipIf(not hasattr(faulthandler, '_stack_overflow'), 'need faulthandler._stack_overflow()') def test_stack_overflow(self): @@ -163,7 +164,8 @@ faulthandler.enable() faulthandler._stack_overflow() """.strip(), 3, - '(?:Segmentation fault|Bus error)') + '(?:Segmentation fault|Bus error)', + other_regex='unable to raise a stack overflow') def test_gil_released(self): self.check_fatal_error(""" diff --git a/Modules/faulthandler.c b/Modules/faulthandler.c index 8ef998db7a5..e8ed3e8a566 100644 --- a/Modules/faulthandler.c +++ b/Modules/faulthandler.c @@ -16,6 +16,9 @@ # define FAULTHANDLER_USER #endif +/* Allocate at maximum 100 MB of the stack to raise the stack overflow */ +#define STACK_OVERFLOW_MAX_SIZE (100*1024*1024) + #define PUTS(fd, str) write(fd, str, strlen(str)) #ifdef HAVE_SIGACTION @@ -742,15 +745,39 @@ faulthandler_fatal_error_py(PyObject *self, PyObject *args) } #if defined(HAVE_SIGALTSTACK) && defined(HAVE_SIGACTION) -static PyObject * -faulthandler_stack_overflow(PyObject *self) +void* +stack_overflow(void *min_sp, void *max_sp, size_t *depth) { /* allocate 4096 bytes on the stack at each call */ unsigned char buffer[4096]; + void *sp = &buffer; + *depth += 1; + if (sp < min_sp || max_sp < sp) + return sp; buffer[0] = 1; - buffer[4095] = 2; - faulthandler_stack_overflow(self); - return PyLong_FromLong(buffer[0] + buffer[4095]); + buffer[4095] = 0; + return stack_overflow(min_sp, max_sp, depth); +} + +static PyObject * +faulthandler_stack_overflow(PyObject *self) +{ + size_t depth, size; + void *sp = &depth, *stop; + + depth = 0; + stop = stack_overflow(sp - STACK_OVERFLOW_MAX_SIZE, + sp + STACK_OVERFLOW_MAX_SIZE, + &depth); + if (sp < stop) + size = stop - sp; + else + size = sp - stop; + PyErr_Format(PyExc_RuntimeError, + "unable to raise a stack overflow (allocated %zu bytes " + "on the stack, %zu recursive calls)", + size, depth); + return NULL; } #endif