perf bpf: check perf_attr_map is compatible with the perf binary

perf_attr_map could be shared among different version of perf binary. Add bperf_attr_map_compatible() to check whether the existing attr_map is compatible with current perf binary. Signed-off-by: Song Liu <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Song Liu <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
mrcsosa · Apr 29, 2021 · fe3dd82 · fe3dd82
1 parent ec8149f
commit fe3dd82
Showing 1 changed file with 19 additions and 0 deletions.
diff --git a/tools/perf/util/bpf_counter.c b/tools/perf/util/bpf_counter.c
@@ -312,6 +312,20 @@ static __u32 bpf_map_get_id(int fd)
 	return map_info.id;
 }
 
+static bool bperf_attr_map_compatible(int attr_map_fd)
+{
+	struct bpf_map_info map_info = {0};
+	__u32 map_info_len = sizeof(map_info);
+	int err;
+
+	err = bpf_obj_get_info_by_fd(attr_map_fd, &map_info, &map_info_len);
+
+	if (err)
+		return false;
+	return (map_info.key_size == sizeof(struct perf_event_attr)) &&
+		(map_info.value_size == sizeof(struct perf_event_attr_map_entry));
+}
+
 static int bperf_lock_attr_map(struct target *target)
 {
 	char path[PATH_MAX];
@@ -346,6 +360,11 @@ static int bperf_lock_attr_map(struct target *target)
 			return -1;
 	}
 
+	if (!bperf_attr_map_compatible(map_fd)) {
+		close(map_fd);
+		return -1;
+
+	}
 	err = flock(map_fd, LOCK_EX);
 	if (err) {
 		close(map_fd);