From 41d585411311abf187e5f09042978fe7073a9375 Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Mon, 15 Mar 2021 13:56:41 +0900 Subject: [PATCH] perf record: Fix memory leak in vDSO found using ASAN I got several memory leak reports from Asan with a simple command. It was because VDSO is not released due to the refcount. Like in __dsos_addnew_id(), it should put the refcount after adding to the list. $ perf record true [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.030 MB perf.data (10 samples) ] ================================================================= ==692599==ERROR: LeakSanitizer: detected memory leaks Direct leak of 439 byte(s) in 1 object(s) allocated from: #0 0x7fea52341037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154 #1 0x559bce4aa8ee in dso__new_id util/dso.c:1256 #2 0x559bce59245a in __machine__addnew_vdso util/vdso.c:132 #3 0x559bce59245a in machine__findnew_vdso util/vdso.c:347 #4 0x559bce50826c in map__new util/map.c:175 #5 0x559bce503c92 in machine__process_mmap2_event util/machine.c:1787 #6 0x559bce512f6b in machines__deliver_event util/session.c:1481 #7 0x559bce515107 in perf_session__deliver_event util/session.c:1551 #8 0x559bce51d4d2 in do_flush util/ordered-events.c:244 #9 0x559bce51d4d2 in __ordered_events__flush util/ordered-events.c:323 #10 0x559bce519bea in __perf_session__process_events util/session.c:2268 #11 0x559bce519bea in perf_session__process_events util/session.c:2297 #12 0x559bce2e7a52 in process_buildids /home/namhyung/project/linux/tools/perf/builtin-record.c:1017 #13 0x559bce2e7a52 in record__finish_output /home/namhyung/project/linux/tools/perf/builtin-record.c:1234 #14 0x559bce2ed4f6 in __cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2026 #15 0x559bce2ed4f6 in cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2858 #16 0x559bce422db4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313 #17 0x559bce2acac8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365 #18 0x559bce2acac8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409 #19 0x559bce2acac8 in main /home/namhyung/project/linux/tools/perf/perf.c:539 #20 0x7fea51e76d09 in __libc_start_main ../csu/libc-start.c:308 Indirect leak of 32 byte(s) in 1 object(s) allocated from: #0 0x7fea52341037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154 #1 0x559bce520907 in nsinfo__copy util/namespaces.c:169 #2 0x559bce50821b in map__new util/map.c:168 #3 0x559bce503c92 in machine__process_mmap2_event util/machine.c:1787 #4 0x559bce512f6b in machines__deliver_event util/session.c:1481 #5 0x559bce515107 in perf_session__deliver_event util/session.c:1551 #6 0x559bce51d4d2 in do_flush util/ordered-events.c:244 #7 0x559bce51d4d2 in __ordered_events__flush util/ordered-events.c:323 #8 0x559bce519bea in __perf_session__process_events util/session.c:2268 #9 0x559bce519bea in perf_session__process_events util/session.c:2297 #10 0x559bce2e7a52 in process_buildids /home/namhyung/project/linux/tools/perf/builtin-record.c:1017 #11 0x559bce2e7a52 in record__finish_output /home/namhyung/project/linux/tools/perf/builtin-record.c:1234 #12 0x559bce2ed4f6 in __cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2026 #13 0x559bce2ed4f6 in cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2858 #14 0x559bce422db4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313 #15 0x559bce2acac8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365 #16 0x559bce2acac8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409 #17 0x559bce2acac8 in main /home/namhyung/project/linux/tools/perf/perf.c:539 #18 0x7fea51e76d09 in __libc_start_main ../csu/libc-start.c:308 SUMMARY: AddressSanitizer: 471 byte(s) leaked in 2 allocation(s). Signed-off-by: Namhyung Kim Acked-by: Jiri Olsa Cc: Alexander Shishkin Cc: Andi Kleen Cc: Ian Rogers Cc: Mark Rutland Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/20210315045641.700430-1-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/vdso.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/tools/perf/util/vdso.c b/tools/perf/util/vdso.c index 3cc91ad048ea..43beb169631d 100644 --- a/tools/perf/util/vdso.c +++ b/tools/perf/util/vdso.c @@ -133,6 +133,8 @@ static struct dso *__machine__addnew_vdso(struct machine *machine, const char *s if (dso != NULL) { __dsos__add(&machine->dsos, dso); dso__set_long_name(dso, long_name, false); + /* Put dso here because __dsos_add already got it */ + dso__put(dso); } return dso;