From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnaldo Carvalho de Melo Subject: [PATCH 19/29] perf script python: Use PyBytes for attr in trace-event-python Date: Sat, 26 Jan 2019 00:18:33 +0100 Message-ID: <20190125231843.2895-20-acme@kernel.org> References: <20190125231843.2895-1-acme@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20190125231843.2895-1-acme@kernel.org> Sender: linux-kernel-owner@vger.kernel.org To: Ingo Molnar Cc: Clark Williams , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Tony Jones , Jiri Olsa , Arnaldo Carvalho de Melo , =?UTF-8?q?Jaroslav=20=C5=A0karvada?= , Jonathan Corbet , Ravi Bangoria , Seeteena Thoufeek List-Id: linux-perf-users.vger.kernel.org From: Tony Jones With Python3. PyUnicode_FromStringAndSize is unsafe to call on attr and will return NULL. Use _PyBytes_FromStringAndSize (as with raw_buf). Below is the observed behavior without the fix. Note it is first necessary to apply the prior fix (Add trace_context extension module to sys,modules): # ldd /usr/bin/perf | grep -i python libpython3.6m.so.1.0 => /usr/lib64/libpython3.6m.so.1.0 (0x00007f8e1dfb2000) # perf record -e raw_syscalls:sys_enter /bin/false [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.018 MB perf.data (21 samples) ] # perf script -g python | cat generated Python script: perf-script.py # perf script -s ./perf-script.py in trace_begin Segmentation fault (core dumped) Signed-off-by: Tony Jones Acked-by: Jiri Olsa Tested-by: Arnaldo Carvalho de Melo Cc: Jaroslav Škarvada Cc: Jonathan Corbet Cc: Ravi Bangoria Cc: Seeteena Thoufeek Fixes: 66dfdff03d19 ("perf tools: Add Python 3 support") Link: http://lkml.kernel.org/r/20190124005229.16146-3-tonyj@suse.de Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/scripting-engines/trace-event-python.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/tools/perf/util/scripting-engines/trace-event-python.c b/tools/perf/util/scripting-engines/trace-event-python.c index 40300d8e80a7..777c97b13905 100644 --- a/tools/perf/util/scripting-engines/trace-event-python.c +++ b/tools/perf/util/scripting-engines/trace-event-python.c @@ -733,8 +733,7 @@ static PyObject *get_perf_sample_dict(struct perf_sample *sample, Py_FatalError("couldn't create Python dictionary"); pydict_set_item_string_decref(dict, "ev_name", _PyUnicode_FromString(perf_evsel__name(evsel))); - pydict_set_item_string_decref(dict, "attr", _PyUnicode_FromStringAndSize( - (const char *)&evsel->attr, sizeof(evsel->attr))); + pydict_set_item_string_decref(dict, "attr", _PyBytes_FromStringAndSize((const char *)&evsel->attr, sizeof(evsel->attr))); pydict_set_item_string_decref(dict_sample, "pid", _PyLong_FromLong(sample->pid)); -- 2.20.1