From d6f1837107c00fa7b2fdb606acf65b33b455dbfd Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Mon, 11 Mar 2019 22:21:09 -0700 Subject: [PATCH] selftests/bpf: fix segfault of test_progs when prog loading failed 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 Signed-off-by: Yonghong Song Acked-by: Song Liu Signed-off-by: Daniel Borkmann --- 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;