From 7fcdccd4237724931d9773d1e3039bfe053a6f52 Mon Sep 17 00:00:00 2001
From: Arnaldo Carvalho de Melo <acme@redhat.com>
Date: Wed, 13 May 2020 10:20:26 -0300
Subject: [PATCH] perf parse-events: Fix incorrect conversion of 'if () free()'
 to 'zfree()'

When applying a patch by Ian I incorrectly converted to zfree() an
expression that involved testing some other struct member, not the one
being freed, which lead to bugs reproduceable by:

  $ perf stat -e i/bs,tsc,L2/o sleep 1
  WARNING: multiple event parsing errors
  Segmentation fault (core dumped)
  $

Fix it by restoring the test for pos->free_str before freeing
pos->val.str, but continue using zfree(&pos->val.str) to set that member
to NULL after freeing it.

Reported-by: Ian Rogers <irogers@google.com>
Fixes: e8dfb81838b1 ("perf parse-events: Fix memory leaks found on parse_events")
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: clang-built-linux@googlegroups.com
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/parse-events.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index e9464b04f149..e37a6a3e6217 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -1480,7 +1480,8 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
 
 		list_for_each_entry_safe(pos, tmp, &config_terms, list) {
 			list_del_init(&pos->list);
-			zfree(&pos->val.str);
+			if (pos->free_str)
+				zfree(&pos->val.str);
 			free(pos);
 		}
 		return -EINVAL;
-- 
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