From patchwork series 502529

https://patchwork.ozlabs.org//project/linuxppc-dev/list/?series=502529

Author: Fox Snowpatch

tools/perf/util/pmu.c

@@ -2117,7 +2117,7 @@ static char *format_alias(char *buf, int len, const struct perf_pmu *pmu,
 						   skip_duplicate_pmus);
 
 	/* Paramemterized events have the parameters shown. */
-	if (strstr(alias->terms, "=?")) {
+	if (!strstr(alias->terms, "=?")) {
 		/* No parameters. */
 		snprintf(buf, len, "%.*s/%s/", (int)pmu_name_len, pmu->name, alias->name);
 		return buf;
@@ -2129,15 +2129,19 @@ static char *format_alias(char *buf, int len, const struct perf_pmu *pmu,
 		pr_err("Failure to parse '%s' terms '%s': %d\n",
 			alias->name, alias->terms, ret);
 		parse_events_terms__exit(&terms);
-		snprintf(buf, len, "%.*s/%s/", (int)pmu_name_len, pmu->name, alias->name);
+		scnprintf(buf, len, "%.*s/%s/", (int)pmu_name_len, pmu->name, alias->name);
 		return buf;
 	}
-	used = snprintf(buf, len, "%.*s/%s", (int)pmu_name_len, pmu->name, alias->name);
+	used = scnprintf(buf, len, "%.*s/%s", (int)pmu_name_len, pmu->name, alias->name);
 
 	list_for_each_entry(term, &terms.terms, list) {
+		const char *name = term->config;
+
+		if (!name)
+			name = parse_events__term_type_str(term->type_term);
 		if (term->type_val == PARSE_EVENTS__TERM_TYPE_STR)
-			used += snprintf(buf + used, sub_non_neg(len, used),
-					",%s=%s", term->config,
+			used += scnprintf(buf + used, sub_non_neg(len, used),
+					",%s=%s", name,
 					term->val.str);
 	}
 	parse_events_terms__exit(&terms);
@@ -2201,6 +2205,7 @@ int perf_pmu__for_each_event(struct perf_pmu *pmu, bool skip_duplicate_pmus,
 	int ret = 0;
 	struct hashmap_entry *entry;
 	size_t bkt;
+	size_t size_rem, len;
 
 	if (perf_pmu__is_tracepoint(pmu))
 		return tp_pmu__for_each_event(pmu, state, cb);
@@ -2234,17 +2239,36 @@ int perf_pmu__for_each_event(struct perf_pmu *pmu, bool skip_duplicate_pmus,
 			}
 			buf_used = strlen(buf) + 1;
 		}
+
 		info.scale_unit = NULL;
 		if (strlen(event->unit) || event->scale != 1.0) {
-			info.scale_unit = buf + buf_used;
-			buf_used += snprintf(buf + buf_used, sizeof(buf) - buf_used,
-					"%G%s", event->scale, event->unit) + 1;
+			/* Check the remaining space */
+			size_rem = sub_non_neg(sizeof(buf), buf_used);
+
+			if (size_rem > 0) {
+				info.scale_unit = buf + buf_used;
+				len = scnprintf(buf + buf_used, size_rem, "%G%s",
+						event->scale, event->unit);
+				/*
+				 * Increment buf_used by 1 only if
+				 * it fits remaining space
+				 */
+				buf_used += min(len + 1, size_rem);
+			}
 		}
 		info.desc = event->desc;
 		info.long_desc = event->long_desc;
-		info.encoding_desc = buf + buf_used;
-		buf_used += snprintf(buf + buf_used, sizeof(buf) - buf_used,
-				"%.*s/%s/", (int)pmu_name_len, info.pmu_name, event->terms) + 1;
+		info.encoding_desc = NULL;
+
+		/* Check the remaining space */
+		size_rem = sub_non_neg(sizeof(buf), buf_used);
+		if (size_rem > 0) {
+			info.encoding_desc = buf + buf_used;
+			len = scnprintf(buf + buf_used, size_rem, "%.*s/%s/",
+					(int)pmu_name_len, info.pmu_name, event->terms);
+			buf_used += min(len + 1, size_rem);
+		}
+
 		info.str = event->terms;
 		info.topic = event->topic;
 		info.deprecated = perf_pmu_alias__check_deprecated(pmu, event);
@@ -2254,7 +2278,7 @@ int perf_pmu__for_each_event(struct perf_pmu *pmu, bool skip_duplicate_pmus,
 	}
 	if (pmu->selectable) {
 		info.name = buf;
-		snprintf(buf, sizeof(buf), "%s//", pmu->name);
+		scnprintf(buf, sizeof(buf), "%s//", pmu->name);
 		info.alias = NULL;
 		info.scale_unit = NULL;
 		info.desc = NULL;