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Signed-off-by: Jordan Rome --- .../selftests/bpf/prog_tests/bpf_iter.c | 68 +++++++++++ .../selftests/bpf/prog_tests/read_vsyscall.c | 1 + .../selftests/bpf/progs/bpf_iter_tasks.c | 110 ++++++++++++++++++ .../selftests/bpf/progs/read_vsyscall.c | 11 +- 4 files changed, 188 insertions(+), 2 deletions(-) -- 2.43.5 diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c index 6f1bfacd7375..add4a18c33bd 100644 --- a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c +++ b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c @@ -323,19 +323,87 @@ static void test_task_pidfd(void) static void test_task_sleepable(void) { struct bpf_iter_tasks *skel; + int pid, status, err, data_pipe[2], finish_pipe[2], c; + char *test_data = NULL; + char *test_data_long = NULL; + char *data[2]; + + if (!ASSERT_OK(pipe(data_pipe), "data_pipe") || + !ASSERT_OK(pipe(finish_pipe), "finish_pipe")) + return; skel = bpf_iter_tasks__open_and_load(); if (!ASSERT_OK_PTR(skel, "bpf_iter_tasks__open_and_load")) return; + pid = fork(); + if (!ASSERT_GE(pid, 0, "fork")) + return; + + if (pid == 0) { + /* child */ + close(data_pipe[0]); + close(finish_pipe[1]); + + test_data = malloc(sizeof(char) * 10); + strncpy(test_data, "test_data", 10); + test_data[9] = '\0'; + + test_data_long = malloc(sizeof(char) * 5000); + for (int i = 0; i < 5000; ++i) { + if (i % 2 == 0) + test_data_long[i] = 'b'; + else + test_data_long[i] = 'a'; + } + test_data_long[4999] = '\0'; + + data[0] = test_data; + data[1] = test_data_long; + + write(data_pipe[1], &data, sizeof(data)); + + /* keep child alive until after the test */ + err = read(finish_pipe[0], &c, 1); + if (err != 1) + exit(-1); + + close(data_pipe[1]); + close(finish_pipe[0]); + _exit(0); + } + + /* parent */ + close(data_pipe[1]); + close(finish_pipe[0]); + + err = read(data_pipe[0], &data, sizeof(data)); + ASSERT_EQ(err, sizeof(data), "read_check"); + + skel->bss->user_ptr = data[0]; + skel->bss->user_ptr_long = data[1]; + skel->bss->pid = pid; + do_dummy_read(skel->progs.dump_task_sleepable); ASSERT_GT(skel->bss->num_expected_failure_copy_from_user_task, 0, "num_expected_failure_copy_from_user_task"); ASSERT_GT(skel->bss->num_success_copy_from_user_task, 0, "num_success_copy_from_user_task"); + ASSERT_GT(skel->bss->num_expected_failure_copy_from_user_task_str, 0, + "num_expected_failure_copy_from_user_task_str"); + ASSERT_GT(skel->bss->num_success_copy_from_user_task_str, 0, + "num_success_copy_from_user_task_str"); bpf_iter_tasks__destroy(skel); + + write(finish_pipe[1], &c, 1); + err = waitpid(pid, &status, 0); + ASSERT_EQ(err, pid, "waitpid"); + ASSERT_EQ(status, 0, "zero_child_exit"); + + close(data_pipe[0]); + close(finish_pipe[1]); } static void test_task_stack(void) diff --git a/tools/testing/selftests/bpf/prog_tests/read_vsyscall.c b/tools/testing/selftests/bpf/prog_tests/read_vsyscall.c index c7b9ba8b1d06..a8d1eaa67020 100644 --- a/tools/testing/selftests/bpf/prog_tests/read_vsyscall.c +++ b/tools/testing/selftests/bpf/prog_tests/read_vsyscall.c @@ -24,6 +24,7 @@ struct read_ret_desc { { .name = "copy_from_user", .ret = -EFAULT }, { .name = "copy_from_user_task", .ret = -EFAULT }, { .name = "copy_from_user_str", .ret = -EFAULT }, + { .name = "copy_from_user_task_str", .ret = -EFAULT }, }; void test_read_vsyscall(void) diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_tasks.c b/tools/testing/selftests/bpf/progs/bpf_iter_tasks.c index bc10c4e4b4fa..966ee5a7b066 100644 --- a/tools/testing/selftests/bpf/progs/bpf_iter_tasks.c +++ b/tools/testing/selftests/bpf/progs/bpf_iter_tasks.c @@ -9,6 +9,13 @@ char _license[] SEC("license") = "GPL"; uint32_t tid = 0; int num_unknown_tid = 0; int num_known_tid = 0; +void *user_ptr = 0; +void *user_ptr_long = 0; +uint32_t pid = 0; + +static char big_str1[5000]; +static char big_str2[5005]; +static char big_str3[4996]; SEC("iter/task") int dump_task(struct bpf_iter__task *ctx) @@ -35,7 +42,9 @@ int dump_task(struct bpf_iter__task *ctx) } int num_expected_failure_copy_from_user_task = 0; +int num_expected_failure_copy_from_user_task_str = 0; int num_success_copy_from_user_task = 0; +int num_success_copy_from_user_task_str = 0; SEC("iter.s/task") int dump_task_sleepable(struct bpf_iter__task *ctx) @@ -44,6 +53,9 @@ int dump_task_sleepable(struct bpf_iter__task *ctx) struct task_struct *task = ctx->task; static const char info[] = " === END ==="; struct pt_regs *regs; + char task_str1[10] = "aaaaaaaaaa"; + char task_str2[10], task_str3[10]; + char task_str4[20] = "aaaaaaaaaaaaaaaaaaaa"; void *ptr; uint32_t user_data = 0; int ret; @@ -78,8 +90,106 @@ int dump_task_sleepable(struct bpf_iter__task *ctx) BPF_SEQ_PRINTF(seq, "%s\n", info); return 0; } + ++num_success_copy_from_user_task; + /* Read an invalid pointer and ensure we get an error */ + ptr = NULL; + ret = bpf_copy_from_user_task_str((char *)task_str1, sizeof(task_str1), ptr, task, 0); + if (ret >= 0 || task_str1[9] != 'a' || task_str1[0] != '\0') { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + + /* Read an invalid pointer and ensure we get error with pad zeros flag */ + ptr = NULL; + ret = bpf_copy_from_user_task_str((char *)task_str1, sizeof(task_str1), + ptr, task, BPF_F_PAD_ZEROS); + if (ret >= 0 || task_str1[9] != '\0' || task_str1[0] != '\0') { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + + ++num_expected_failure_copy_from_user_task_str; + + /* Same length as the string */ + ret = bpf_copy_from_user_task_str((char *)task_str2, 10, user_ptr, task, 0); + /* only need to do the task pid check once */ + if (bpf_strncmp(task_str2, 10, "test_data\0") != 0 || ret != 10 || task->tgid != pid) { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + + /* Shorter length than the string */ + ret = bpf_copy_from_user_task_str((char *)task_str3, 2, user_ptr, task, 0); + if (bpf_strncmp(task_str3, 2, "t\0") != 0 || ret != 2) { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + + /* Longer length than the string */ + ret = bpf_copy_from_user_task_str((char *)task_str4, 20, user_ptr, task, 0); + if (bpf_strncmp(task_str4, 10, "test_data\0") != 0 || ret != 10 + || task_str4[sizeof(task_str4) - 1] != 'a') { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + + /* Longer length than the string with pad zeros flag */ + ret = bpf_copy_from_user_task_str((char *)task_str4, 20, user_ptr, task, BPF_F_PAD_ZEROS); + if (bpf_strncmp(task_str4, 10, "test_data\0") != 0 || ret != 10 + || task_str4[sizeof(task_str4) - 1] != '\0') { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + + /* Longer length than the string past a page boundary */ + ret = bpf_copy_from_user_task_str(big_str1, 5000, user_ptr, task, 0); + if (bpf_strncmp(big_str1, 10, "test_data\0") != 0 || ret != 10) { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + + /* String that crosses a page boundary */ + ret = bpf_copy_from_user_task_str(big_str1, 5000, user_ptr_long, task, BPF_F_PAD_ZEROS); + if (bpf_strncmp(big_str1, 4, "baba") != 0 || ret != 5000 + || bpf_strncmp(big_str1 + 4996, 4, "bab\0") != 0) { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + + for (int i = 0; i < 4999; ++i) { + if (i % 2 == 0) { + if (big_str1[i] != 'b') { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + } else { + if (big_str1[i] != 'a') { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + } + } + + /* Longer length than the string that crosses a page boundary */ + ret = bpf_copy_from_user_task_str(big_str2, 5005, user_ptr_long, task, BPF_F_PAD_ZEROS); + if (bpf_strncmp(big_str2, 4, "baba") != 0 || ret != 5000 + || bpf_strncmp(big_str2 + 4996, 5, "bab\0\0") != 0) { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + + /* Shorter length than the string that crosses a page boundary */ + ret = bpf_copy_from_user_task_str(big_str3, 4996, user_ptr_long, task, 0); + if (bpf_strncmp(big_str3, 4, "baba") != 0 || ret != 4996 + || bpf_strncmp(big_str3 + 4992, 4, "bab\0") != 0) { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + + ++num_success_copy_from_user_task_str; + if (ctx->meta->seq_num == 0) BPF_SEQ_PRINTF(seq, " tgid gid data\n"); diff --git a/tools/testing/selftests/bpf/progs/read_vsyscall.c b/tools/testing/selftests/bpf/progs/read_vsyscall.c index 39ebef430059..395591374d4f 100644 --- a/tools/testing/selftests/bpf/progs/read_vsyscall.c +++ b/tools/testing/selftests/bpf/progs/read_vsyscall.c @@ -8,14 +8,16 @@ int target_pid = 0; void *user_ptr = 0; -int read_ret[9]; +int read_ret[10]; char _license[] SEC("license") = "GPL"; /* - * This is the only kfunc, the others are helpers + * These are the kfuncs, the others are helpers */ int bpf_copy_from_user_str(void *dst, u32, const void *, u64) __weak __ksym; +int bpf_copy_from_user_task_str(void *dst, u32, const void *, + struct task_struct *, u64) __weak __ksym; SEC("fentry/" SYS_PREFIX "sys_nanosleep") int do_probe_read(void *ctx) @@ -47,6 +49,11 @@ int do_copy_from_user(void *ctx) read_ret[7] = bpf_copy_from_user_task(buf, sizeof(buf), user_ptr, bpf_get_current_task_btf(), 0); read_ret[8] = bpf_copy_from_user_str((char *)buf, sizeof(buf), user_ptr, 0); + read_ret[9] = bpf_copy_from_user_task_str((char *)buf, + sizeof(buf), + user_ptr, + bpf_get_current_task_btf(), + 0); return 0; }