Commit 448d732c authored by Ian Rogers's avatar Ian Rogers Committed by Arnaldo Carvalho de Melo
Browse files

perf parse: Add parse events handle error 



Parse event error handling may overwrite one error string with another
creating memory leaks. Introduce a helper routine that warns about
multiple error messages as well as avoiding the memory leak.

A reproduction of this problem can be seen with:

  perf stat -e c/c/

After this change this produces:
WARNING: multiple event parsing errors
event syntax error: 'c/c/'
                       \___ unknown term

valid terms: event,filter_rem,filter_opc0,edge,filter_isoc,filter_tid,filter_loc,filter_nc,inv,umask,filter_opc1,tid_en,thresh,filter_all_op,filter_not_nm,filter_state,filter_nm,config,config1,config2,name,period,percore
Run 'perf list' for a list of valid events

 Usage: perf stat [<options>] [<command>]

    -e, --event <event>   event selector. use 'perf list' to list available events

Signed-off-by: default avatarIan Rogers <irogers@google.com>
Acked-by: default avatarJiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: bpf@vger.kernel.org
Cc: clang-built-linux@googlegroups.com
Cc: netdev@vger.kernel.org
Link: http://lore.kernel.org/lkml/20191030223448.12930-2-irogers@google.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent ef5502a1

tools/perf/util/parse-events.c

+51 −31
Original line number Diff line number Diff line
@@ -182,6 +182,20 @@ static int tp_event_has_id(const char *dir_path, struct dirent *evt_dir) 


#define MAX_EVENT_LENGTH 512



void parse_events__handle_error(struct parse_events_error *err, int idx,

				char *str, char *help)

{

	if (WARN(!str, "WARNING: failed to provide error string\n")) {

		free(help);

		return;

	}

	WARN_ONCE(err->str, "WARNING: multiple event parsing errors\n");

	err->idx = idx;

	free(err->str);

	err->str = str;

	free(err->help);

	err->help = help;

}



struct tracepoint_path *tracepoint_id_to_path(u64 config)

{
@@ -932,11 +946,11 @@ static int check_type_val(struct parse_events_term *term, 
		return 0;



	if (err) {

		err->idx = term->err_val;

		if (type == PARSE_EVENTS__TERM_TYPE_NUM)

			err->str = strdup("expected numeric value");

		else

			err->str = strdup("expected string value");

		parse_events__handle_error(err, term->err_val,

					type == PARSE_EVENTS__TERM_TYPE_NUM

					? strdup("expected numeric value")

					: strdup("expected string value"),

					NULL);

	}

	return -EINVAL;

}
@@ -972,8 +986,11 @@ static bool config_term_shrinked; 
static bool

config_term_avail(int term_type, struct parse_events_error *err)

{

	char *err_str;



	if (term_type < 0 || term_type >= __PARSE_EVENTS__TERM_TYPE_NR) {

		err->str = strdup("Invalid term_type");

		parse_events__handle_error(err, -1,

					strdup("Invalid term_type"), NULL);

		return false;

	}

	if (!config_term_shrinked)
@@ -992,9 +1009,9 @@ config_term_avail(int term_type, struct parse_events_error *err) 
			return false;



		/* term_type is validated so indexing is safe */

		if (asprintf(&err->str, "'%s' is not usable in 'perf stat'",

			     config_term_names[term_type]) < 0)

			err->str = NULL;

		if (asprintf(&err_str, "'%s' is not usable in 'perf stat'",

				config_term_names[term_type]) >= 0)

			parse_events__handle_error(err, -1, err_str, NULL);

		return false;

	}

}
@@ -1036,17 +1053,20 @@ do { \ 
	case PARSE_EVENTS__TERM_TYPE_BRANCH_SAMPLE_TYPE:

		CHECK_TYPE_VAL(STR);

		if (strcmp(term->val.str, "no") &&

		    parse_branch_str(term->val.str, &attr->branch_sample_type)) {

			err->str = strdup("invalid branch sample type");

			err->idx = term->err_val;

		    parse_branch_str(term->val.str,

				    &attr->branch_sample_type)) {

			parse_events__handle_error(err, term->err_val,

					strdup("invalid branch sample type"),

					NULL);

			return -EINVAL;

		}

		break;

	case PARSE_EVENTS__TERM_TYPE_TIME:

		CHECK_TYPE_VAL(NUM);

		if (term->val.num > 1) {

			err->str = strdup("expected 0 or 1");

			err->idx = term->err_val;

			parse_events__handle_error(err, term->err_val,

						strdup("expected 0 or 1"),

						NULL);

			return -EINVAL;

		}

		break;
@@ -1080,8 +1100,9 @@ do { \ 
	case PARSE_EVENTS__TERM_TYPE_PERCORE:

		CHECK_TYPE_VAL(NUM);

		if ((unsigned int)term->val.num > 1) {

			err->str = strdup("expected 0 or 1");

			err->idx = term->err_val;

			parse_events__handle_error(err, term->err_val,

						strdup("expected 0 or 1"),

						NULL);

			return -EINVAL;

		}

		break;
@@ -1089,9 +1110,9 @@ do { \ 
		CHECK_TYPE_VAL(NUM);

		break;

	default:

		err->str = strdup("unknown term");

		err->idx = term->err_term;

		err->help = parse_events_formats_error_string(NULL);

		parse_events__handle_error(err, term->err_term,

				strdup("unknown term"),

				parse_events_formats_error_string(NULL));

		return -EINVAL;

	}
@@ -1142,9 +1163,9 @@ static int config_term_tracepoint(struct perf_event_attr *attr, 
		return config_term_common(attr, term, err);

	default:

		if (err) {

			err->idx = term->err_term;

			err->str = strdup("unknown term");

			err->help = strdup("valid terms: call-graph,stack-size\n");

			parse_events__handle_error(err, term->err_term,

				strdup("unknown term"),

				strdup("valid terms: call-graph,stack-size\n"));

		}

		return -EINVAL;

	}
@@ -1323,10 +1344,12 @@ int parse_events_add_pmu(struct parse_events_state *parse_state, 


	pmu = perf_pmu__find(name);

	if (!pmu) {

		if (asprintf(&err->str,

		char *err_str;



		if (asprintf(&err_str,

				"Cannot find PMU `%s'. Missing kernel support?",

				name) < 0)

			err->str = NULL;

				name) >= 0)

			parse_events__handle_error(err, -1, err_str, NULL);

		return -EINVAL;

	}
@@ -2802,13 +2825,10 @@ void parse_events__clear_array(struct parse_events_array *a) 
void parse_events_evlist_error(struct parse_events_state *parse_state,

			       int idx, const char *str)

{

	struct parse_events_error *err = parse_state->error;



	if (!err)

	if (!parse_state->error)

		return;

	err->idx = idx;

	err->str = strdup(str);

	WARN_ONCE(!err->str, "WARNING: failed to allocate error string");



	parse_events__handle_error(parse_state->error, idx, strdup(str), NULL);

}



static void config_terms_list(char *buf, size_t buf_sz)

tools/perf/util/parse-events.h

+2 −0
Original line number Diff line number Diff line
@@ -124,6 +124,8 @@ struct parse_events_state { 
	struct list_head	  *terms;

};



void parse_events__handle_error(struct parse_events_error *err, int idx,

				char *str, char *help);

void parse_events__shrink_config_terms(void);

int parse_events__is_hardcoded_term(struct parse_events_term *term);

int parse_events_term__num(struct parse_events_term **term,

tools/perf/util/pmu.c

+18 −12
Original line number Diff line number Diff line
@@ -1050,9 +1050,9 @@ static int pmu_config_term(struct list_head *formats, 
		if (err) {

			char *pmu_term = pmu_formats_string(formats);



			err->idx  = term->err_term;

			err->str  = strdup("unknown term");

			err->help = parse_events_formats_error_string(pmu_term);

			parse_events__handle_error(err, term->err_term,

				strdup("unknown term"),

				parse_events_formats_error_string(pmu_term));

			free(pmu_term);

		}

		return -EINVAL;
@@ -1080,8 +1080,9 @@ static int pmu_config_term(struct list_head *formats, 
		if (term->no_value &&

		    bitmap_weight(format->bits, PERF_PMU_FORMAT_BITS) > 1) {

			if (err) {

				err->idx = term->err_val;

				err->str = strdup("no value assigned for term");

				parse_events__handle_error(err, term->err_val,

					   strdup("no value assigned for term"),

					   NULL);

			}

			return -EINVAL;

		}
@@ -1094,8 +1095,9 @@ static int pmu_config_term(struct list_head *formats, 
						term->config, term->val.str);

			}

			if (err) {

				err->idx = term->err_val;

				err->str = strdup("expected numeric value");

				parse_events__handle_error(err, term->err_val,

					strdup("expected numeric value"),

					NULL);

			}

			return -EINVAL;

		}
@@ -1108,11 +1110,15 @@ static int pmu_config_term(struct list_head *formats, 
	max_val = pmu_format_max_value(format->bits);

	if (val > max_val) {

		if (err) {

			err->idx = term->err_val;

			if (asprintf(&err->str,

			char *err_str;



			parse_events__handle_error(err, term->err_val,

				asprintf(&err_str,

				    "value too big for format, maximum is %llu",

				     (unsigned long long)max_val) < 0)

				err->str = strdup("value too big for format");

				    (unsigned long long)max_val) < 0

				    ? strdup("value too big for format")

				    : err_str,

				    NULL);

			return -EINVAL;

		}

		/*

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