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Date:   Mon,  9 Oct 2023 11:39:17 -0700
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Subject: [PATCH v3 15/18] tools api: Avoid potential double free
From:   Ian Rogers <irogers@google.com>
To:     Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Tom Rix <trix@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jiri Olsa <jolsa@kernel.org>,
        Namhyung Kim <namhyung@kernel.org>,
        Ian Rogers <irogers@google.com>,
        Adrian Hunter <adrian.hunter@intel.com>,
        Yang Jihong <yangjihong1@huawei.com>,
        Huacai Chen <chenhuacai@kernel.org>,
        Ming Wang <wangming01@loongson.cn>,
        Kan Liang <kan.liang@linux.intel.com>,
        Ravi Bangoria <ravi.bangoria@amd.com>, llvm@lists.linux.dev,
        linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org,
        bpf@vger.kernel.org
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io__getline will free the line on error but it doesn't clear the out
argument. This may lead to the line being freed twice, like in
tools/perf/util/srcline.c as detected by clang-tidy.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/lib/api/io.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/lib/api/io.h b/tools/lib/api/io.h
index 9fc429d2852d..a77b74c5fb65 100644
--- a/tools/lib/api/io.h
+++ b/tools/lib/api/io.h
@@ -180,6 +180,7 @@ static inline ssize_t io__getline(struct io *io, char **line_out, size_t *line_l
 	return line_len;
 err_out:
 	free(line);
+	*line_out = NULL;
 	return -ENOMEM;
 }
 
-- 
2.42.0.609.gbb76f46606-goog