Re: [PATCH 8/9] perf test: Free aliases for PMU event map aliases test

From: John Garry
Date: Mon Sep 07 2020 - 06:31:45 EST


On 07/09/2020 04:45, Namhyung Kim wrote:
The aliases were never released causing the following leaks:

Indirect leak of 1224 byte(s) in 9 object(s) allocated from:
#0 0x7feefb830628 in malloc (/lib/x86_64-linux-gnu/libasan.so.5+0x107628)
#1 0x56332c8f1b62 in __perf_pmu__new_alias util/pmu.c:322
#2 0x56332c8f401f in pmu_add_cpu_aliases_map util/pmu.c:778
#3 0x56332c792ce9 in __test__pmu_event_aliases tests/pmu-events.c:295
#4 0x56332c792ce9 in test_aliases tests/pmu-events.c:367
#5 0x56332c76a09b in run_test tests/builtin-test.c:410
#6 0x56332c76a09b in test_and_print tests/builtin-test.c:440
#7 0x56332c76ce69 in __cmd_test tests/builtin-test.c:695
#8 0x56332c76ce69 in cmd_test tests/builtin-test.c:807
#9 0x56332c7d2214 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
#10 0x56332c6701a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
#11 0x56332c6701a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
#12 0x56332c6701a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
#13 0x7feefb359cc9 in __libc_start_main ../csu/libc-start.c:308

Cc: John Garry <john.garry@xxxxxxxxxx>
Fixes: 956a78356c24c ("perf test: Test pmu-events aliases")
Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
tools/perf/tests/pmu-events.c | 5 +++++
tools/perf/util/pmu.c | 2 +-
tools/perf/util/pmu.h | 1 +
3 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/tools/perf/tests/pmu-events.c b/tools/perf/tests/pmu-events.c
index eb19f9a0bc15..d3517a74d95e 100644
--- a/tools/perf/tests/pmu-events.c
+++ b/tools/perf/tests/pmu-events.c
@@ -274,6 +274,7 @@ static int __test__pmu_event_aliases(char *pmu_name, int *count)
int res = 0;
bool use_uncore_table;
struct pmu_events_map *map = __test_pmu_get_events_map();
+ struct perf_pmu_alias *a, *tmp;
if (!map)
return -1;
@@ -347,6 +348,10 @@ static int __test__pmu_event_aliases(char *pmu_name, int *count)
pmu_name, alias->name);
}
+ list_for_each_entry_safe(a, tmp, &aliases, list) {
+ list_del(&a->list);
+ perf_pmu_free_alias(a);

This looks ok.

I also notice that we have other paths like this, where the allocated pmu (and aliases) are not freed for later error paths, it seems:

parse_events_add_pmu() -> perf_pmu_find() -> pmu_lookup() -> pmu_add_cpu_aliases().

I had a quick look at the rest of the series, and could not see if we fix up any of this.

Cheers,
john

+ }
free(pmu);
return res;
}
diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index f1688e1f6ed7..555cb3524c25 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -274,7 +274,7 @@ static void perf_pmu_update_alias(struct perf_pmu_alias *old,
}
/* Delete an alias entry. */
-static void perf_pmu_free_alias(struct perf_pmu_alias *newalias)
+void perf_pmu_free_alias(struct perf_pmu_alias *newalias)
{
zfree(&newalias->name);
zfree(&newalias->desc);
diff --git a/tools/perf/util/pmu.h b/tools/perf/util/pmu.h
index 44ccbdbb1c37..b63c4c5e335e 100644
--- a/tools/perf/util/pmu.h
+++ b/tools/perf/util/pmu.h
@@ -113,6 +113,7 @@ void pmu_add_cpu_aliases_map(struct list_head *head, struct perf_pmu *pmu,
struct pmu_events_map *perf_pmu__find_map(struct perf_pmu *pmu);
bool pmu_uncore_alias_match(const char *pmu_name, const char *name);
+void perf_pmu_free_alias(struct perf_pmu_alias *alias);
int perf_pmu__convert_scale(const char *scale, char **end, double *sval);