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| author | Jackie Liu <jackieliu2113@gmail.com> | 2021-03-16 02:24:53 +0100 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2021-03-16 14:01:44 +0100 |
| commit | 1a096ae46e21b73f83a581e617f76326c1de592d (patch) | |
| tree | cd4a31171223f24b643605bb7fc2194d86ea8b27 /tools/perf/util/bpf-event.c | |
| parent | perf pmu: Validate raw event with sysfs exported format bits (diff) | |
| download | linux-1a096ae46e21b73f83a581e617f76326c1de592d.tar.xz linux-1a096ae46e21b73f83a581e617f76326c1de592d.zip | |
perf top: Fix BPF support related crash with perf_event_paranoid=3 + kptr_restrict
After installing the libelf-dev package and compiling perf, if we have
kptr_restrict=2 and perf_event_paranoid=3 'perf top' will 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
check before use.
Also plug some leaks on the error path.
Suggested-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: jackie liu <liuyun01@kylinos.cn>
Link: http://lore.kernel.org/lkml/20210316012453.1156-1-liuyun01@kylinos.cn
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util/bpf-event.c')
| -rw-r--r-- | tools/perf/util/bpf-event.c | 13 |
1 files 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); |