[PATCH 6.4 470/800] perf dwarf-aux: Fix off-by-one in die_get_varname()

Greg Kroah-Hartman
2023-07-16T20:14:50Z

From: Namhyung Kim <namhyung@kernel.org>

[ Upstream commit 3abfcfd847717d232e36963f31a361747c388fe7 ]

The die_get_varname() returns "(unknown_type)" string if it failed to
find a type for the variable. But it had a space before the opening
parenthesis and it made the closing parenthesis cut off due to the
off-by-one in the string length (14).

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Fixes: 88fd633cdfa19060 ("perf probe: No need to use formatting strbuf method")
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230612234102.3909116-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
tools/perf/util/dwarf-aux.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c
index b074144097710..3bff678745635 100644
--- a/tools/perf/util/dwarf-aux.c
+++ b/tools/perf/util/dwarf-aux.c
@@ -1103,7 +1103,7 @@ int die_get_varname(Dwarf_Die *vr_die, struct strbuf *buf)
ret = die_get_typename(vr_die, buf);
if (ret < 0) {
pr_debug("Failed to get type, make it unknown.\n");
- ret = strbuf_add(buf, " (unknown_type)", 14);
+ ret = strbuf_add(buf, "(unknown_type)", 14);
}

return ret < 0 ? ret : strbuf_addf(buf, "\t%s", dwarf_diename(vr_die));
--
2.39.2