[patch] [python] PR python/15461 (gate architecture calls)

Phil Muldoon
2013-08-28T12:04:54Z

This patch gates calls to architecture.name and
architecture.disassemble. If the underlying GDB architecture is NULL,
calls to those Python functions will result in an assert call.

Something I thought about is not allowing gdb.Architecture to be
instantiated directly, but I could not think of a clean way to do
this. Also, all other GDB Python classes can be instantiated
(though, not very usefully, IE foo = gdb.Frame())

In any case, this patch gates those calls mentioned above.

Cheers,

Phil

2013-08-28 Phil Muldoon <pmuldoon@redhat.com>

PR python/15461

* python/py-arch.c (ARCHPY_REQUIRE_VALID): New macro.
(archpy_name): Check for valid architecture.
(archpy_disassemble): Ditto.

2013-08-28 Phil Muldoon <pmuldoon@redhat.com>

* gdb.python/py-arch.exp: Tests for invalid architecture.

--

diff --git a/gdb/python/py-arch.c b/gdb/python/py-arch.c
index 7098a8a..2775c9d 100644
--- a/gdb/python/py-arch.c
+++ b/gdb/python/py-arch.c
@@ -30,6 +30,14 @@ typedef struct arch_object_type_object {

static struct gdbarch_data *arch_object_data = NULL;

+/* Require a valid Architecture. */
+#define ARCHPY_REQUIRE_VALID (arch_obj, arch) \
+ do { \
+ arch = arch_object_to_gdbarch (arch_obj); \
+ if (arch == NULL) \
+ error (_("Architecture is invalid.")); \
+ } while (0)
+
static PyTypeObject arch_object_type
CPYCHECKER_TYPE_OBJECT_FOR_TYPEDEF ("arch_object");

@@ -82,9 +90,19 @@ gdbarch_to_arch_object (struct gdbarch *gdbarch)
static PyObject *
archpy_name (PyObject *self, PyObject *args)
{
- struct gdbarch *gdbarch = arch_object_to_gdbarch (self);
- const char *name = (gdbarch_bfd_arch_info (gdbarch))->printable_name;
- PyObject *py_name = PyString_FromString (name);
+ struct gdbarch *gdbarch = NULL;
+ const char *name;
+ PyObject *py_name;
+ volatile struct gdb_exception except;
+
+ TRY_CATCH (except, RETURN_MASK_ALL)
+ {
+ ARCHPY_REQUIRE_VALID (self, gdbarch);
+ }
+ GDB_PY_HANDLE_EXCEPTION (except);
+
+ name = (gdbarch_bfd_arch_info (gdbarch))->printable_name;
+ py_name = PyString_FromString (name);

return py_name;
}
@@ -104,7 +122,14 @@ archpy_disassemble (PyObject *self, PyObject *args, PyObject *kw)
gdb_py_ulongest start_temp;
long count = 0, i;
PyObject *result_list, *end_obj = NULL, *count_obj = NULL;
- struct gdbarch *gdbarch = arch_object_to_gdbarch (self);
+ struct gdbarch *gdbarch = NULL;
+ volatile struct gdb_exception except;
+
+ TRY_CATCH (except, RETURN_MASK_ALL)
+ {
+ ARCHPY_REQUIRE_VALID (self, gdbarch);
+ }
+ GDB_PY_HANDLE_EXCEPTION (except);

if (!PyArg_ParseTupleAndKeywords (args, kw, GDB_PY_LLU_ARG "|OO", keywords,
&start_temp, &end_obj, &count_obj))
diff --git a/gdb/testsuite/gdb.python/py-arch.exp b/gdb/testsuite/gdb.python/py-arch.exp
index 4e736b8..0d32ef7 100644
--- a/gdb/testsuite/gdb.python/py-arch.exp
+++ b/gdb/testsuite/gdb.python/py-arch.exp
@@ -12,6 +12,7 @@
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
+load_lib gdb-python.exp

standard_testfile

@@ -26,6 +27,14 @@ if ![runto_main] {
return -1
}

+# Test python/15461. Invalid architectures should not trigger an
+# internal GDB assert.
+gdb_py_test_silent_cmd "python empty = gdb.Architecture()" "get empty arch" 0
+gdb_test "python print(empty.name())" ".*Architecture is invalid.*" \
+ "Test empty architecture.name does not trigger an assert"
+gdb_test "python print(empty.disassemble())" ".*Architecture is invalid.*" \
+ "Test empty architecture.disassemble does not trigger an assert"
+
gdb_py_test_silent_cmd "python frame = gdb.selected_frame()" "get frame" 0
gdb_py_test_silent_cmd "python arch = frame.architecture()" "get arch" 0
gdb_py_test_silent_cmd "python pc = frame.pc()" "get pc" 0