tools: Free BTF objects at various locations

Make sure to call btf__free() (and not simply free(), which does not
free all pointers stored in the struct) on pointers to struct btf
objects retrieved at various locations.

These were found while updating the calls to btf__get_from_id().

Fixes: 999d82cbc044 ("tools/bpf: enhance test_btf file testing to test func info")
Fixes: 254471e57a86 ("tools/bpf: bpftool: add support for func types")
Fixes: 7b612e291a5a ("perf tools: Synthesize PERF_RECORD_* for loaded BPF programs")
Fixes: d56354dc4909 ("perf tools: Save bpf_prog_info and BTF of new BPF programs")
Fixes: 47c09d6a9f67 ("bpftool: Introduce "prog profile" command")
Fixes: fa853c4b839e ("perf stat: Enable counting events for BPF programs")
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210729162028.29512-5-quentin@isovalent.com

4 files changed, 9 insertions, 4 deletions

diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
index cc48726740ad..9d709b427665 100644
--- a/tools/bpf/bpftool/prog.c
+++ b/tools/bpf/bpftool/prog.c
@@ -781,6 +781,8 @@ prog_dump(struct bpf_prog_info *info, enum dump_mode mode,
 		kernel_syms_destroy(&dd);
 	}
 
+	btf__free(btf);
+
 	return 0;
 }
 
@@ -2002,8 +2004,8 @@ static char *profile_target_name(int tgt_fd)
 	struct bpf_prog_info_linear *info_linear;
 	struct bpf_func_info *func_info;
 	const struct btf_type *t;
+	struct btf *btf = NULL;
 	char *name = NULL;
-	struct btf *btf;
 
 	info_linear = bpf_program__get_prog_info_linear(
 		tgt_fd, 1UL << BPF_PROG_INFO_FUNC_INFO);
@@ -2027,6 +2029,7 @@ static char *profile_target_name(int tgt_fd)
 	}
 	name = strdup(btf__name_by_offset(btf, t->name_off));
 out:
+	btf__free(btf);
 	free(info_linear);
 	return name;
 }
diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c
index cdecda1ddd36..17a9844e4fbf 100644
--- a/tools/perf/util/bpf-event.c
+++ b/tools/perf/util/bpf-event.c
@@ -296,7 +296,7 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session,
 
 out:
 	free(info_linear);
-	free(btf);
+	btf__free(btf);
 	return err ? -1 : 0;
 }
 
@@ -486,7 +486,7 @@ static void perf_env__add_bpf_info(struct perf_env *env, u32 id)
 	perf_env__fetch_btf(env, btf_id, btf);
 
 out:
-	free(btf);
+	btf__free(btf);
 	close(fd);
 }
 
diff --git a/tools/perf/util/bpf_counter.c b/tools/perf/util/bpf_counter.c
index 8150e03367bb..beca55129b0b 100644
--- a/tools/perf/util/bpf_counter.c
+++ b/tools/perf/util/bpf_counter.c
@@ -64,8 +64,8 @@ static char *bpf_target_prog_name(int tgt_fd)
 	struct bpf_prog_info_linear *info_linear;
 	struct bpf_func_info *func_info;
 	const struct btf_type *t;
+	struct btf *btf = NULL;
 	char *name = NULL;
-	struct btf *btf;
 
 	info_linear = bpf_program__get_prog_info_linear(
 		tgt_fd, 1UL << BPF_PROG_INFO_FUNC_INFO);
@@ -89,6 +89,7 @@ static char *bpf_target_prog_name(int tgt_fd)
 	}
 	name = strdup(btf__name_by_offset(btf, t->name_off));
 out:
+	btf__free(btf);
 	free(info_linear);
 	return name;
 }
diff --git a/tools/testing/selftests/bpf/prog_tests/btf.c b/tools/testing/selftests/bpf/prog_tests/btf.c
index 857e3f26086f..68e415f4d33c 100644
--- a/tools/testing/selftests/bpf/prog_tests/btf.c
+++ b/tools/testing/selftests/bpf/prog_tests/btf.c
@@ -4386,6 +4386,7 @@ skip:
 	fprintf(stderr, "OK");
 
 done:
+	btf__free(btf);
 	free(func_info);
 	bpf_object__close(obj);
 }