[PATCH 2/7] perf report: fix memory leak in addr2line when called by addr2inlines

From: Namhyung Kim
Date: Wed May 24 2017 - 02:22:25 EST


From: Milian Wolff <milian.wolff@xxxxxxxx>

When a filename was found in addr2line it was duplicated via strdup
but never freed. Now we pass NULL and handle this gracefully in
addr2line.

Detected by Valgrind:

==16331== 1,680 bytes in 21 blocks are definitely lost in loss record 148 of 220
==16331== at 0x4C2AF1F: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==16331== by 0x672FA69: strdup (in /usr/lib/libc-2.25.so)
==16331== by 0x52769F: addr2line (srcline.c:256)
==16331== by 0x52769F: addr2inlines (srcline.c:294)
==16331== by 0x52769F: dso__parse_addr_inlines (srcline.c:502)
==16331== by 0x574D7A: inline__fprintf (hist.c:41)
==16331== by 0x574D7A: ipchain__fprintf_graph (hist.c:147)
==16331== by 0x57518A: __callchain__fprintf_graph (hist.c:212)
==16331== by 0x5753CF: callchain__fprintf_graph.constprop.6 (hist.c:337)
==16331== by 0x57738E: hist_entry__fprintf (hist.c:628)
==16331== by 0x57738E: hists__fprintf (hist.c:882)
==16331== by 0x44A20F: perf_evlist__tty_browse_hists (builtin-report.c:399)
==16331== by 0x44A20F: report__browse_hists (builtin-report.c:491)
==16331== by 0x44A20F: __cmd_report (builtin-report.c:624)
==16331== by 0x44A20F: cmd_report (builtin-report.c:1054)
==16331== by 0x4A49CE: run_builtin (perf.c:296)
==16331== by 0x4A4CC0: handle_internal_command (perf.c:348)
==16331== by 0x434371: run_argv (perf.c:392)
==16331== by 0x434371: main (perf.c:530)

Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Yao Jin <yao.jin@xxxxxxxxxxxxxxx>
Signed-off-by: Milian Wolff <milian.wolff@xxxxxxxx>
Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
tools/perf/util/srcline.c | 23 +++++++++++++----------
1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/tools/perf/util/srcline.c b/tools/perf/util/srcline.c
index df051a52393c..5e376d64d59e 100644
--- a/tools/perf/util/srcline.c
+++ b/tools/perf/util/srcline.c
@@ -230,7 +230,10 @@ static int addr2line(const char *dso_name, u64 addr,

bfd_map_over_sections(a2l->abfd, find_address_in_section, a2l);

- if (a2l->found && unwind_inlines) {
+ if (!a2l->found)
+ return 0;
+
+ if (unwind_inlines) {
int cnt = 0;

while (bfd_find_inliner_info(a2l->abfd, &a2l->filename,
@@ -243,6 +246,8 @@ static int addr2line(const char *dso_name, u64 addr,
a2l->line, node,
dso) != 0)
return 0;
+ // found at least one inline frame
+ ret = 1;
}
}

@@ -252,14 +257,14 @@ static int addr2line(const char *dso_name, u64 addr,
}
}

- if (a2l->found && a2l->filename) {
- *file = strdup(a2l->filename);
- *line = a2l->line;
-
- if (*file)
- ret = 1;
+ if (file) {
+ *file = a2l->filename ? strdup(a2l->filename) : NULL;
+ ret = *file ? 1 : 0;
}

+ if (line)
+ *line = a2l->line;
+
return ret;
}

@@ -278,8 +283,6 @@ void dso__free_a2l(struct dso *dso)
static struct inline_node *addr2inlines(const char *dso_name, u64 addr,
struct dso *dso)
{
- char *file = NULL;
- unsigned int line = 0;
struct inline_node *node;

node = zalloc(sizeof(*node));
@@ -291,7 +294,7 @@ static struct inline_node *addr2inlines(const char *dso_name, u64 addr,
INIT_LIST_HEAD(&node->val);
node->addr = addr;

- if (!addr2line(dso_name, addr, &file, &line, dso, TRUE, node))
+ if (!addr2line(dso_name, addr, NULL, NULL, dso, TRUE, node))
goto out_free_inline_node;

if (list_empty(&node->val))
--
2.13.0