selftests/bpf: Task_work selftest cleanup fixes

task_work selftest does not properly handle cleanup during failures:
 * destroy bpf_link
 * perf event fd is passed to bpf_link, no need to close it if link was
 created successfully
 * goto cleanup if fork() failed, close pipe.

Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250924142954.129519-2-mykyta.yatsenko5@gmail.com

diff --git a/tools/testing/selftests/bpf/prog_tests/test_task_work.c b/tools/testing/selftests/bpf/prog_tests/test_task_work.c
index 666585270fbf997c7f3664718aeea77304a7628c..774b31a5f6ca12ba3ade230ee26d495c823096ed 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/test_task_work.c
+++ b/tools/testing/selftests/bpf/prog_tests/test_task_work.c
@@ -55,8 +55,8 @@ static void task_work_run(const char *prog_name, const char *map_name)
        struct task_work *skel;
        struct bpf_program *prog;
        struct bpf_map *map;
-       struct bpf_link *link;
-       int err, pe_fd = 0, pid, status, pipefd[2];
+       struct bpf_link *link = NULL;
+       int err, pe_fd = -1, pid, status, pipefd[2];
        char user_string[] = "hello world";
 
        if (!ASSERT_NEQ(pipe(pipefd), -1, "pipe"))
@@ -77,7 +77,11 @@ static void task_work_run(const char *prog_name, const char *map_name)
                (void)num;
                exit(0);
        }
-       ASSERT_GT(pid, 0, "fork() failed");
+       if (!ASSERT_GT(pid, 0, "fork() failed")) {
+               close(pipefd[0]);
+               close(pipefd[1]);
+               return;
+       }
 
        skel = task_work__open();
        if (!ASSERT_OK_PTR(skel, "task_work__open"))
@@ -112,6 +116,8 @@ static void task_work_run(const char *prog_name, const char *map_name)
        if (!ASSERT_OK_PTR(link, "attach_perf_event"))
                goto cleanup;
 
+       /* perf event fd ownership is passed to bpf_link */
+       pe_fd = -1;
        close(pipefd[0]);
        write(pipefd[1], user_string, 1);
        close(pipefd[1]);
@@ -126,8 +132,9 @@ static void task_work_run(const char *prog_name, const char *map_name)
 cleanup:
        if (pe_fd >= 0)
                close(pe_fd);
+       bpf_link__destroy(link);
        task_work__destroy(skel);
-       if (pid) {
+       if (pid > 0) {
                close(pipefd[0]);
                write(pipefd[1], user_string, 1);
                close(pipefd[1]);