From d95daf5accf4a72005daa13fbb1d1bd8709f2861 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Thu, 18 Jul 2019 11:28:37 -0300 Subject: [PATCH] perf probe: Avoid calling freeing routine multiple times for same pointer When perf_add_probe_events() we call cleanup_perf_probe_events() for the pev pointer it receives, then, as part of handling this failure the main 'perf probe' goes on and calls cleanup_params() and that will again call cleanup_perf_probe_events()for the same pointer, so just set nevents to zero when handling the failure of perf_add_probe_events() to avoid the double free. Cc: Adrian Hunter Cc: Jiri Olsa Cc: Masami Hiramatsu Cc: Namhyung Kim Link: https://lkml.kernel.org/n/tip-x8qgma4g813z96dvtw9w219q@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-probe.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c index 6418782951a4..3d0ffd41fb55 100644 --- a/tools/perf/builtin-probe.c +++ b/tools/perf/builtin-probe.c @@ -698,6 +698,16 @@ __cmd_probe(int argc, const char **argv) ret = perf_add_probe_events(params.events, params.nevents); if (ret < 0) { + + /* + * When perf_add_probe_events() fails it calls + * cleanup_perf_probe_events(pevs, npevs), i.e. + * cleanup_perf_probe_events(params.events, params.nevents), which + * will call clear_perf_probe_event(), so set nevents to zero + * to avoid cleanup_params() to call clear_perf_probe_event() again + * on the same pevs. + */ + params.nevents = 0; pr_err_with_code(" Error: Failed to add events.", ret); return ret; } -- 2.30.2