From 3db79d21cf9cd1f52b4e0b2497e47b2967495a25 Mon Sep 17 00:00:00 2001 From: Jordan Rome Date: Sat, 11 Nov 2023 18:30:10 -0800 Subject: [PATCH] selftests/bpf: Add assert for user stacks in test_task_stack commit 727a92d62fd6a382b4c5972008e45667e707b0e4 upstream. This is a follow up to: commit b8e3a87a627b ("bpf: Add crosstask check to __bpf_get_stack"). This test ensures that the task iterator only gets a single user stack (for the current task). Signed-off-by: Jordan Rome Signed-off-by: Andrii Nakryiko Acked-by: Stanislav Fomichev Link: https://lore.kernel.org/bpf/20231112023010.144675-1-linux@jordanrome.com Signed-off-by: Greg Kroah-Hartman --- tools/testing/selftests/bpf/prog_tests/bpf_iter.c | 2 ++ tools/testing/selftests/bpf/progs/bpf_iter_task_stack.c | 5 +++++ 2 files changed, 7 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c index 1f021681..f141e27 100644 --- a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c +++ b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c @@ -334,6 +334,8 @@ static void test_task_stack(void) do_dummy_read(skel->progs.dump_task_stack); do_dummy_read(skel->progs.get_task_user_stacks); + ASSERT_EQ(skel->bss->num_user_stacks, 1, "num_user_stacks"); + bpf_iter_task_stack__destroy(skel); } diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_task_stack.c b/tools/testing/selftests/bpf/progs/bpf_iter_task_stack.c index f2b8167..442f4ca 100644 --- a/tools/testing/selftests/bpf/progs/bpf_iter_task_stack.c +++ b/tools/testing/selftests/bpf/progs/bpf_iter_task_stack.c @@ -35,6 +35,8 @@ int dump_task_stack(struct bpf_iter__task *ctx) return 0; } +int num_user_stacks = 0; + SEC("iter/task") int get_task_user_stacks(struct bpf_iter__task *ctx) { @@ -51,6 +53,9 @@ int get_task_user_stacks(struct bpf_iter__task *ctx) if (res <= 0) return 0; + /* Only one task, the current one, should succeed */ + ++num_user_stacks; + buf_sz += res; /* If the verifier doesn't refine bpf_get_task_stack res, and instead -- 2.7.4