Messages in this thread | | | Date | Sat, 5 Aug 2023 23:01:48 +0900 | From | Masami Hiramatsu (Google) <> | Subject | Re: [PATCH 1/1] perf probe: Free string returned by synthesize_perf_probe_point() on failure to add a probe |
| |
On Fri, 4 Aug 2023 13:22:44 -0300 Arnaldo Carvalho de Melo <acme@kernel.org> wrote:
> Building perf with EXTRA_CFLAGS="-fsanitize=address" a leak is detect > when trying to add a probe to a non-existent function: > > # perf probe -x ~/bin/perf dso__neW > Probe point 'dso__neW' not found. > Error: Failed to add events. > > ================================================================= > ==296634==ERROR: LeakSanitizer: detected memory leaks > > Direct leak of 128 byte(s) in 1 object(s) allocated from: > #0 0x7f67642ba097 in calloc (/lib64/libasan.so.8+0xba097) > #1 0x7f67641a76f1 in allocate_cfi (/lib64/libdw.so.1+0x3f6f1) > > Direct leak of 65 byte(s) in 1 object(s) allocated from: > #0 0x7f67642b95b5 in __interceptor_realloc.part.0 (/lib64/libasan.so.8+0xb95b5) > #1 0x6cac75 in strbuf_grow util/strbuf.c:64 > #2 0x6ca934 in strbuf_init util/strbuf.c:25 > #3 0x9337d2 in synthesize_perf_probe_point util/probe-event.c:2018 > #4 0x92be51 in try_to_find_probe_trace_events util/probe-event.c:964 > #5 0x93d5c6 in convert_to_probe_trace_events util/probe-event.c:3512 > #6 0x93d6d5 in convert_perf_probe_events util/probe-event.c:3529 > #7 0x56f37f in perf_add_probe_events /var/home/acme/git/perf-tools-next/tools/perf/builtin-probe.c:354 > #8 0x572fbc in __cmd_probe /var/home/acme/git/perf-tools-next/tools/perf/builtin-probe.c:738 > #9 0x5730f2 in cmd_probe /var/home/acme/git/perf-tools-next/tools/perf/builtin-probe.c:766 > #10 0x635d81 in run_builtin /var/home/acme/git/perf-tools-next/tools/perf/perf.c:323 > #11 0x6362c1 in handle_internal_command /var/home/acme/git/perf-tools-next/tools/perf/perf.c:377 > #12 0x63667a in run_argv /var/home/acme/git/perf-tools-next/tools/perf/perf.c:421 > #13 0x636b8d in main /var/home/acme/git/perf-tools-next/tools/perf/perf.c:537 > #14 0x7f676302950f in __libc_start_call_main (/lib64/libc.so.6+0x2950f) > > SUMMARY: AddressSanitizer: 193 byte(s) leaked in 2 allocation(s). > # > > synthesize_perf_probe_point() returns a "detached" strbuf, i.e. a > malloc'ed string that needs to be free'd. > > An audit will be performed to find other such cases.
Thanks for finding it!
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> > Cc: Adrian Hunter <adrian.hunter@intel.com> > Cc: Ian Rogers <irogers@google.com> > Cc: Jiri Olsa <jolsa@kernel.org> > Cc: Masami Hiramatsu <mhiramat@kernel.org> > Cc: Namhyung Kim <namhyung@kernel.org> > Link: https://lore.kernel.org/lkml/ > Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> > --- > tools/perf/util/probe-event.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c > index 2d056f02ae408a64..c7bfeab610a3679a 100644 > --- a/tools/perf/util/probe-event.c > +++ b/tools/perf/util/probe-event.c > @@ -961,8 +961,9 @@ static int try_to_find_probe_trace_events(struct perf_probe_event *pev, > debuginfo__delete(dinfo); > > if (ntevs == 0) { /* No error but failed to find probe point. */ > - pr_warning("Probe point '%s' not found.\n", > - synthesize_perf_probe_point(&pev->point)); > + char *probe_point = synthesize_perf_probe_point(&pev->point); > + pr_warning("Probe point '%s' not found.\n", probe_point); > + free(probe_point); > return -ENODEV; > } else if (ntevs < 0) { > /* Error path : ntevs < 0 */ > -- > 2.37.1 >
-- Masami Hiramatsu (Google) <mhiramat@kernel.org>
| |