After install the libelf-dev package and compiling perf, kptr_restrict=2
and perf_event_paranoid=3 will cause perf top to crash, because the
value of /proc/kallsyms cannot be obtained, which leads to
info->jited_ksyms == NULL. In order to solve this problem, Add a
judgment before use.
v3->v4:
Fix memory leaks in more places
v2->v3:
free info_linear memory and move code above, don't do those extra btf
checks.
Suggested-by: Jiri Olsa <jo...@redhat.com>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Ingo Molnar <mi...@redhat.com>
Cc: Arnaldo Carvalho de Melo <a...@kernel.org>
Cc: Mark Rutland <mark.rutl...@arm.com>
Cc: Alexander Shishkin <alexander.shish...@linux.intel.com>
Cc: Namhyung Kim <namhy...@kernel.org>
Signed-off-by: Jackie Liu <liuyu...@kylinos.cn>
---
tools/perf/util/bpf-event.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)
diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c
index 57d58c81a5f8..cdecda1ddd36 100644
--- a/tools/perf/util/bpf-event.c
+++ b/tools/perf/util/bpf-event.c
@@ -196,25 +196,32 @@ static int perf_event__synthesize_one_bpf_prog(struct
perf_session *session,
}
if (info_linear->info_len < offsetof(struct bpf_prog_info, prog_tags)) {
+ free(info_linear);
pr_debug("%s: the kernel is too old, aborting\n", __func__);
return -2;
}
info = &info_linear->info;
+ if (!info->jited_ksyms) {
+ free(info_linear);
+ return -1;
+ }
/* number of ksyms, func_lengths, and tags should match */
sub_prog_cnt = info->nr_jited_ksyms;
if (sub_prog_cnt != info->nr_prog_tags ||
- sub_prog_cnt != info->nr_jited_func_lens)
+ sub_prog_cnt != info->nr_jited_func_lens) {
+ free(info_linear);
return -1;
+ }
/* check BTF func info support */
if (info->btf_id && info->nr_func_info && info->func_info_rec_size) {
/* btf func info number should be same as sub_prog_cnt */
if (sub_prog_cnt != info->nr_func_info) {
pr_debug("%s: mismatch in BPF sub program count and BTF
function info count, aborting\n", __func__);
- err = -1;
- goto out;
+ free(info_linear);
+ return -1;
}
if (btf__get_from_id(info->btf_id, &btf)) {
pr_debug("%s: failed to get BTF of id %u, aborting\n",
__func__, info->btf_id);
--
2.25.1
