[PATCH 5.10 033/167] perf inject: Fix dso->nsinfo refcounting

From: Greg Kroah-Hartman
Date: Mon Jul 26 2021 - 12:18:47 EST


From: Riccardo Mancini <rickyman7@xxxxxxxxx>

[ Upstream commit 0967ebffe098157180a0bbd180ac90348c6e07d7 ]

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@xxxxxxxxx>
Fixes: 27c9c3424fc217da ("perf inject: Add --buildid-all option")
Cc: Ian Rogers <irogers@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Link: http://lore.kernel.org/lkml/55223bc8821b34ccb01f92ef1401c02b6a32e61f.1626343282.git.rickyman7@xxxxxxxxx
[ Split from a larger patch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
tools/perf/builtin-inject.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/tools/perf/builtin-inject.c b/tools/perf/builtin-inject.c
index 5320ac1b1285..ec7e46b63551 100644
--- a/tools/perf/builtin-inject.c
+++ b/tools/perf/builtin-inject.c
@@ -358,9 +358,10 @@ 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);
--
2.30.2