Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Wed,  8 Jun 2022 22:23:52 -0700
In-Reply-To: <20220609052355.1300162-1-irogers@google.com>
Message-Id: <20220609052355.1300162-2-irogers@google.com>
Mime-Version: 1.0
References: <20220609052355.1300162-1-irogers@google.com>
Subject: [PATCH v2 1/4] libperf evsel: Open shouldn't leak fd on failure
From:   Ian Rogers <irogers@google.com>
To:     Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jiri Olsa <jolsa@kernel.org>,
        Namhyung Kim <namhyung@kernel.org>,
        Kajol Jain <kjain@linux.ibm.com>,
        Andi Kleen <ak@linux.intel.com>,
        Adrian Hunter <adrian.hunter@intel.com>,
        Anshuman Khandual <anshuman.khandual@arm.com>,
        linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org,
        Rob Herring <robh@kernel.org>
Cc:     Stephane Eranian <eranian@google.com>,
        Ian Rogers <irogers@google.com>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

If the perf_event_open fails the fd is opened but the fd is only freed
by closing (not by delete). Typically when an open fails you don't call
close and so this results in a memory leak. To avoid this, add a close
when open fails.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/lib/perf/evsel.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/tools/lib/perf/evsel.c b/tools/lib/perf/evsel.c
index c1d58673f6ef..952f3520d5c2 100644
--- a/tools/lib/perf/evsel.c
+++ b/tools/lib/perf/evsel.c
@@ -149,23 +149,30 @@ int perf_evsel__open(struct perf_evsel *evsel, struct perf_cpu_map *cpus,
 			int fd, group_fd, *evsel_fd;
 
 			evsel_fd = FD(evsel, idx, thread);
-			if (evsel_fd == NULL)
-				return -EINVAL;
+			if (evsel_fd == NULL) {
+				err = -EINVAL;
+				goto out;
+			}
 
 			err = get_group_fd(evsel, idx, thread, &group_fd);
 			if (err < 0)
-				return err;
+				goto out;
 
 			fd = sys_perf_event_open(&evsel->attr,
 						 threads->map[thread].pid,
 						 cpu, group_fd, 0);
 
-			if (fd < 0)
-				return -errno;
+			if (fd < 0) {
+				err = -errno;
+				goto out;
+			}
 
 			*evsel_fd = fd;
 		}
 	}
+out:
+	if (err)
+		perf_evsel__close(evsel);
 
 	return err;
 }
-- 
2.36.1.255.ge46751e96f-goog