From 306411a8bf75568380bf00f37eb535c7c09eef0d Mon Sep 17 00:00:00 2001 From: Riccardo Mancini Date: Thu, 15 Jul 2021 18:07:06 +0200 Subject: [PATCH] perf probe: Fix dso->nsinfo refcounting [ Upstream commit dedeb4be203b382ba7245d13079bc3b0f6d40c65 ] ASan reports a memory leak of nsinfo during the execution of: # perf test "31: Lookup mmap thread". The leak is caused by a refcounted variable being replaced without dropping the refcount. This patch makes sure that the refcnt of nsinfo is decreased whenever a refcounted variable is replaced with a new value. Signed-off-by: Riccardo Mancini Fixes: 544abd44c7064c8a ("perf probe: Allow placing uprobes in alternate namespaces.") Cc: Ian Rogers Cc: Jiri Olsa Cc: Krister Johansen Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/55223bc8821b34ccb01f92ef1401c02b6a32e61f.1626343282.git.rickyman7@gmail.com [ Split from a larger patch ] Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin --- tools/perf/util/probe-event.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index 8eae2afff71a..07db6cfad65b 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -180,8 +180,10 @@ struct map *get_target_map(const char *target, struct nsinfo *nsi, bool user) struct map *map; map = dso__new_map(target); - if (map && map->dso) + if (map && map->dso) { + nsinfo__put(map->dso->nsinfo); map->dso->nsinfo = nsinfo__get(nsi); + } return map; } else { return kernel_get_module_map(target);