> On Mar 11, 2019, at 10:21 PM, Yonghong Song <y...@fb.com> wrote:
>
> The test_progs subtests, test_spin_lock() and test_map_lock(),
> requires BTF present to run successfully.
> Currently, when BTF failed to load, test_progs will segfault,
> $ ./test_progs
> ...
> 12: (bf) r1 = r8
> 13: (85) call bpf_spin_lock#93
> map 'hash_map' has to have BTF in order to use bpf_spin_lock
>
> libbpf: -- END LOG --
> libbpf: failed to load program 'map_lock_demo'
> libbpf: failed to load object './test_map_lock.o'
> test_map_lock:bpf_prog_load errno 13
> Segmentation fault
>
> The segfault is caused by uninitialized variable "obj", which
> is used in bpf_object__close(obj), when bpf prog failed to load.
>
> Initializing variable "obj" to NULL in two occasions fixed the problem.
> $ ./test_progs
> ...
> Summary: 219 PASSED, 2 FAILED
>
> Fixes: b4d4556c3266 ("selftests/bpf: add bpf_spin_lock verifier tests")
> Fixes: ba72a7b4badb ("selftests/bpf: test for BPF_F_LOCK")
> Reported-by: Daniel Borkmann <dan...@iogearbox.net>
> Signed-off-by: Yonghong Song <y...@fb.com>
Acked-by: Song Liu <songliubrav...@fb.com>
> ---
> tools/testing/selftests/bpf/prog_tests/map_lock.c | 2 +-
> tools/testing/selftests/bpf/prog_tests/spinlock.c | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/map_lock.c
> b/tools/testing/selftests/bpf/prog_tests/map_lock.c
> index 90f8a206340a..ee99368c595c 100644
> --- a/tools/testing/selftests/bpf/prog_tests/map_lock.c
> +++ b/tools/testing/selftests/bpf/prog_tests/map_lock.c
> @@ -37,7 +37,7 @@ void test_map_lock(void)
> const char *file = "./test_map_lock.o";
> int prog_fd, map_fd[2], vars[17] = {};
> pthread_t thread_id[6];
> - struct bpf_object *obj;
> + struct bpf_object *obj = NULL;
> int err = 0, key = 0, i;
> void *ret;
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/spinlock.c
> b/tools/testing/selftests/bpf/prog_tests/spinlock.c
> index 9a573a9675d7..114ebe6a438e 100644
> --- a/tools/testing/selftests/bpf/prog_tests/spinlock.c
> +++ b/tools/testing/selftests/bpf/prog_tests/spinlock.c
> @@ -5,7 +5,7 @@ void test_spinlock(void)
> {
> const char *file = "./test_spin_lock.o";
> pthread_t thread_id[4];
> - struct bpf_object *obj;
> + struct bpf_object *obj = NULL;
> int prog_fd;
> int err = 0, i;
> void *ret;
> --
> 2.17.1
>
