perf inject: Fix dso->nsinfo refcounting

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 when a
refcounted variable is replaced with a new value.

Signed-off-by: Riccardo Mancini <rickyman7@gmail.com>
Fixes: 27c9c3424fc217da ("perf inject: Add --buildid-all option")
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/55223bc8821b34ccb01f92ef1401c02b6a32e61f.1626343282.git.rickyman7@gmail.com
[ Split from a larger patch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/builtin-inject.c b/tools/perf/builtin-inject.c
index 5d6f583e2cd35be0fffa4c0979d5fbd9e01f0588..ffd2b25039e36e1d5749cf031613a1f663d77294 100644 (file)
--- a/tools/perf/builtin-inject.c
+++ b/tools/perf/builtin-inject.c
@@ -361,9 +361,10 @@ static struct dso *findnew_dso(int pid, int tid, const char *filename,
                dso = machine__findnew_dso_id(machine, filename, id);
        }
 
-       if (dso)
+       if (dso) {
+               nsinfo__put(dso->nsinfo);
                dso->nsinfo = nsi;
-       else
+       } else
                nsinfo__put(nsi);
 
        thread__put(thread);