perf header: Fix memory leaks when processing feature headers

These leaks were found with leak sanitizer running "perf pipe recording
and injection test".

In pipe mode feat_fd may hold onto an events struct that needs freeing.

When string features are processed they may overwrite an already created
string, so free this before the overwrite.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20211118201730.2302927-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 79cce216727e03021937c5bac4b569f07b494f39..e3c1a532d05910bf634a1d22cc452eaba7dc057f 100644 (file)
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -2321,6 +2321,7 @@ out:
 #define FEAT_PROCESS_STR_FUN(__feat, __feat_env) \
 static int process_##__feat(struct feat_fd *ff, void *data __maybe_unused) \
 {\
+       free(ff->ph->env.__feat_env);                \
        ff->ph->env.__feat_env = do_read_string(ff); \
        return ff->ph->env.__feat_env ? 0 : -ENOMEM; \
 }
@@ -4124,6 +4125,7 @@ int perf_event__process_feature(struct perf_session *session,
        struct perf_record_header_feature *fe = (struct perf_record_header_feature *)event;
        int type = fe->header.type;
        u64 feat = fe->feat_id;
+       int ret = 0;
 
        if (type < 0 || type >= PERF_RECORD_HEADER_MAX) {
                pr_warning("invalid record type %d in pipe-mode\n", type);
@@ -4141,11 +4143,13 @@ int perf_event__process_feature(struct perf_session *session,
        ff.size = event->header.size - sizeof(*fe);
        ff.ph = &session->header;
 
-       if (feat_ops[feat].process(&ff, NULL))
-               return -1;
+       if (feat_ops[feat].process(&ff, NULL)) {
+               ret = -1;
+               goto out;
+       }
 
        if (!feat_ops[feat].print || !tool->show_feat_hdr)
-               return 0;
+               goto out;
 
        if (!feat_ops[feat].full_only ||
            tool->show_feat_hdr >= SHOW_FEAT_HEADER_FULL_INFO) {
@@ -4154,8 +4158,9 @@ int perf_event__process_feature(struct perf_session *session,
                fprintf(stdout, "# %s info available, use -I to display\n",
                        feat_ops[feat].name);
        }
-
-       return 0;
+out:
+       free_event_desc(ff.events);
+       return ret;
 }
 
 size_t perf_event__fprintf_event_update(union perf_event *event, FILE *fp)