[PATCH v4 5/9] perf tools: ensure config and str in terms are unique

From: Ian Rogers
Date: Fri Oct 25 2019 - 14:09:22 EST


Make it easier to release memory associated with parse event terms by
duplicating the string for the config name and ensuring the val string
is a duplicate.

Currently the parser may memory leak terms and this is addressed in a
later patch.

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/perf/util/parse-events.c | 51 ++++++++++++++++++++++++++++------
tools/perf/util/parse-events.y | 4 ++-
2 files changed, 45 insertions(+), 10 deletions(-)

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 4c4c6f3e866a..fb6436a74869 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -1414,7 +1414,6 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
int parse_events_multi_pmu_add(struct parse_events_state *parse_state,
char *str, struct list_head **listp)
{
- struct list_head *head;
struct parse_events_term *term;
struct list_head *list;
struct perf_pmu *pmu = NULL;
@@ -1431,19 +1430,30 @@ int parse_events_multi_pmu_add(struct parse_events_state *parse_state,

list_for_each_entry(alias, &pmu->aliases, list) {
if (!strcasecmp(alias->name, str)) {
+ struct list_head *head;
+ char *config;
+
head = malloc(sizeof(struct list_head));
if (!head)
return -1;
INIT_LIST_HEAD(head);
- if (parse_events_term__num(&term, PARSE_EVENTS__TERM_TYPE_USER,
- str, 1, false, &str, NULL) < 0)
+ config = strdup(str);
+ if (!config)
+ return -1;
+ if (parse_events_term__num(&term,
+ PARSE_EVENTS__TERM_TYPE_USER,
+ config, 1, false, &config,
+ NULL) < 0) {
+ free(list);
+ free(config);
return -1;
+ }
list_add_tail(&term->list, head);

if (!parse_events_add_pmu(parse_state, list,
pmu->name, head,
true, true)) {
- pr_debug("%s -> %s/%s/\n", str,
+ pr_debug("%s -> %s/%s/\n", config,
pmu->name, alias->str);
ok++;
}
@@ -1452,8 +1462,10 @@ int parse_events_multi_pmu_add(struct parse_events_state *parse_state,
}
}
}
- if (!ok)
+ if (!ok) {
+ free(list);
return -1;
+ }
*listp = list;
return 0;
}
@@ -2748,30 +2760,51 @@ int parse_events_term__sym_hw(struct parse_events_term **term,
char *config, unsigned idx)
{
struct event_symbol *sym;
+ char *str;
struct parse_events_term temp = {
.type_val = PARSE_EVENTS__TERM_TYPE_STR,
.type_term = PARSE_EVENTS__TERM_TYPE_USER,
- .config = config ?: (char *) "event",
+ .config = config,
};

+ if (!temp.config) {
+ temp.config = strdup("event");
+ if (!temp.config)
+ return -ENOMEM;
+ }
BUG_ON(idx >= PERF_COUNT_HW_MAX);
sym = &event_symbols_hw[idx];

- return new_term(term, &temp, (char *) sym->symbol, 0);
+ str = strdup(sym->symbol);
+ if (!str)
+ return -ENOMEM;
+ return new_term(term, &temp, str, 0);
}

int parse_events_term__clone(struct parse_events_term **new,
struct parse_events_term *term)
{
+ char *str;
struct parse_events_term temp = {
.type_val = term->type_val,
.type_term = term->type_term,
- .config = term->config,
+ .config = NULL,
.err_term = term->err_term,
.err_val = term->err_val,
};

- return new_term(new, &temp, term->val.str, term->val.num);
+ if (term->config) {
+ temp.config = strdup(term->config);
+ if (!temp.config)
+ return -ENOMEM;
+ }
+ if (term->type_val == PARSE_EVENTS__TERM_TYPE_NUM)
+ return new_term(new, &temp, NULL, term->val.num);
+
+ str = strdup(term->val.str);
+ if (!str)
+ return -ENOMEM;
+ return new_term(new, &temp, str, 0);
}

int parse_events_copy_term_list(struct list_head *old,
diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y
index ffa1a1b63796..545ab7cefc20 100644
--- a/tools/perf/util/parse-events.y
+++ b/tools/perf/util/parse-events.y
@@ -665,9 +665,11 @@ PE_NAME array '=' PE_VALUE
PE_DRV_CFG_TERM
{
struct parse_events_term *term;
+ char *config = strdup($1);

+ ABORT_ON(!config);
ABORT_ON(parse_events_term__str(&term, PARSE_EVENTS__TERM_TYPE_DRV_CFG,
- $1, $1, &@1, NULL));
+ config, $1, &@1, NULL));
$$ = term;
}

--
2.24.0.rc0.303.g954a862665-goog