From e655c1f1bd14804f398df7da029c4a7e3f9ccd7f Mon Sep 17 00:00:00 2001 From: Liang Luo Date: Thu, 9 Jul 2026 18:03:40 +0800 Subject: [PATCH] selftests/sched_ext: Fix bpf_link leak on early return in prog_run In prog_run's run(), the bpf_link is attached early but only destroyed on the success path. The three SCX_EQ assertions between attach and destroy expand to a direct 'return SCX_TEST_FAIL', so if any of them triggers, bpf_link__destroy() is never reached and the BPF scheduler stays loaded. All subsequent tests then fail to attach because SCX is not in the DISABLED state. Convert those assertions to explicit checks that jump to a unified 'out' label which always runs the cleanup, matching the pattern used in cyclic_kick_wait.c. Fixes: a5db7817af78 ("sched_ext: Add selftests") Signed-off-by: Liang Luo Reviewed-by: Andrea Righi Signed-off-by: Tejun Heo --- tools/testing/selftests/sched_ext/prog_run.c | 36 +++++++++++++++----- 1 file changed, 27 insertions(+), 9 deletions(-) diff --git a/tools/testing/selftests/sched_ext/prog_run.c b/tools/testing/selftests/sched_ext/prog_run.c index 05974820ca69..1129ec2aaddc 100644 --- a/tools/testing/selftests/sched_ext/prog_run.c +++ b/tools/testing/selftests/sched_ext/prog_run.c @@ -28,7 +28,8 @@ static enum scx_test_status setup(void **ctx) static enum scx_test_status run(void *ctx) { struct prog_run *skel = ctx; - struct bpf_link *link; + struct bpf_link *link = NULL; + enum scx_test_status status = SCX_TEST_PASS; int prog_fd, err = 0; prog_fd = bpf_program__fd(skel->progs.prog_run_syscall); @@ -42,23 +43,40 @@ static enum scx_test_status run(void *ctx) link = bpf_map__attach_struct_ops(skel->maps.prog_run_ops); if (!link) { SCX_ERR("Failed to attach scheduler"); - close(prog_fd); - return SCX_TEST_FAIL; + status = SCX_TEST_FAIL; + goto out; } err = bpf_prog_test_run_opts(prog_fd, &topts); - SCX_EQ(err, 0); + if (err) { + SCX_ERR("BPF_PROG_RUN failed (%d)", err); + status = SCX_TEST_FAIL; + goto out; + } /* Assumes uei.kind is written last */ while (skel->data->uei.kind == EXIT_KIND(SCX_EXIT_NONE)) sched_yield(); - SCX_EQ(skel->data->uei.kind, EXIT_KIND(SCX_EXIT_UNREG_BPF)); - SCX_EQ(skel->data->uei.exit_code, 0xdeadbeef); - close(prog_fd); - bpf_link__destroy(link); + if (skel->data->uei.kind != EXIT_KIND(SCX_EXIT_UNREG_BPF)) { + SCX_ERR("Unexpected exit kind: %llu", + (unsigned long long)skel->data->uei.kind); + status = SCX_TEST_FAIL; + goto out; + } + if (skel->data->uei.exit_code != 0xdeadbeef) { + SCX_ERR("Unexpected exit code: %lld", + (long long)skel->data->uei.exit_code); + status = SCX_TEST_FAIL; + goto out; + } - return SCX_TEST_PASS; +out: + close(prog_fd); + if (link) + bpf_link__destroy(link); + + return status; } static void cleanup(void *ctx)