Re: [PATCH V2] perf script python: Fail check on dynamic allocation

[Adrian Hunter <adrian.hunter@intel.com>]

On 19/11/23 06:09, Paran Lee wrote:
> Add PyList_New() Fail check in
> get_field_numeric_entry() function
> and dynamic allocation checking for
> set_regs_in_dict(), python_start_script().

Try to wrap lines at 75 characters (max).

> 
> Signed-off-by: Paran Lee <p4ranlee@gmail.com>
> Reviewed-by: Seonghee Jin<shjy180909@gmail.com>

Other instances of that email address in the kernel git repo
use the name MichelleJin <shjy180909@gmail.com>.  Might as well
be consistent.

> ---
>  .../util/scripting-engines/trace-event-python.c | 17 +++++++++++++++--
>  1 file changed, 15 insertions(+), 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 94312741443a..f96968ba371f 100644
> --- a/tools/perf/util/scripting-engines/trace-event-python.c
> +++ b/tools/perf/util/scripting-engines/trace-event-python.c
> @@ -353,6 +353,8 @@ static PyObject *get_field_numeric_entry(struct tep_event *event,
>  
>  	if (is_array) {
>  		list = PyList_New(field->arraylen);
> +		if (!list)
> +			Py_FatalError("couldn't create Python list");
>  		item_size = field->size / field->arraylen;
>  		n_items = field->arraylen;
>  	} else {
> @@ -754,7 +756,7 @@ static void regs_map(struct regs_dump *regs, uint64_t mask, const char *arch, ch
>  	}
>  }
>  
> -static void set_regs_in_dict(PyObject *dict,
> +static int set_regs_in_dict(PyObject *dict,
>  			     struct perf_sample *sample,
>  			     struct evsel *evsel)
>  {
> @@ -770,6 +772,8 @@ static void set_regs_in_dict(PyObject *dict,
>  	 */
>  	int size = __sw_hweight64(attr->sample_regs_intr) * 28;
>  	char *bf = malloc(size);
> +	if (!bf)
> +		return -1;
>  
>  	regs_map(&sample->intr_regs, attr->sample_regs_intr, arch, bf, size);
>  
> @@ -781,6 +785,8 @@ static void set_regs_in_dict(PyObject *dict,
>  	pydict_set_item_string_decref(dict, "uregs",
>  			_PyUnicode_FromString(bf));
>  	free(bf);
> +
> +	return 0;
>  }
>  
>  static void set_sym_in_dict(PyObject *dict, struct addr_location *al,
> @@ -920,7 +926,8 @@ static PyObject *get_perf_sample_dict(struct perf_sample *sample,
>  			PyLong_FromUnsignedLongLong(sample->cyc_cnt));
>  	}
>  
> -	set_regs_in_dict(dict, sample, evsel);
> +	if (!set_regs_in_dict(dict, sample, evsel))

The condition is the wrong way around.

> +		Py_FatalError("Failed to setting regs in dict");
>  
>  	return dict;
>  }
> @@ -1918,12 +1925,18 @@ static int python_start_script(const char *script, int argc, const char **argv,
>  	scripting_context->session = session;
>  #if PY_MAJOR_VERSION < 3
>  	command_line = malloc((argc + 1) * sizeof(const char *));
> +	if (!command_line)
> +		return -1;
> +
>  	command_line[0] = script;
>  	for (i = 1; i < argc + 1; i++)
>  		command_line[i] = argv[i - 1];
>  	PyImport_AppendInittab(name, initperf_trace_context);
>  #else
>  	command_line = malloc((argc + 1) * sizeof(wchar_t *));
> +	if (!command_line)
> +		return -1;
> +
>  	command_line[0] = Py_DecodeLocale(script, NULL);
>  	for (i = 1; i < argc + 1; i++)
>  		command_line[i] = Py_DecodeLocale(argv[i - 1], NULL);