diff options
author | Song Liu <songliubraving@fb.com> | 2021-02-25 15:43:16 -0800 |
---|---|---|
committer | Alexei Starovoitov <ast@kernel.org> | 2021-02-26 11:51:48 -0800 |
commit | 1f87dcf116adedd6b9f47258d4fdf4fa9ce74002 (patch) | |
tree | db016f90ba6da4f318862d36d17f97ffaf237cf6 /tools/testing/selftests/bpf/progs/task_local_storage.c | |
parent | bc235cdb423a2daed6f337676006a66557429cd1 (diff) |
selftests/bpf: Add non-BPF_LSM test for task local storage
Task local storage is enabled for tracing programs. Add two tests for
task local storage without CONFIG_BPF_LSM.
The first test stores a value in sys_enter and read it back in sys_exit.
The second test checks whether the kernel allows allocating task local
storage in exit_creds() (which it should not).
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210225234319.336131-4-songliubraving@fb.com
Diffstat (limited to 'tools/testing/selftests/bpf/progs/task_local_storage.c')
-rw-r--r-- | tools/testing/selftests/bpf/progs/task_local_storage.c | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/task_local_storage.c b/tools/testing/selftests/bpf/progs/task_local_storage.c new file mode 100644 index 000000000000..80a0a20db88d --- /dev/null +++ b/tools/testing/selftests/bpf/progs/task_local_storage.c @@ -0,0 +1,64 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2021 Facebook */ + +#include "vmlinux.h" +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_tracing.h> + +char _license[] SEC("license") = "GPL"; + +struct { + __uint(type, BPF_MAP_TYPE_TASK_STORAGE); + __uint(map_flags, BPF_F_NO_PREALLOC); + __type(key, int); + __type(value, long); +} enter_id SEC(".maps"); + +#define MAGIC_VALUE 0xabcd1234 + +pid_t target_pid = 0; +int mismatch_cnt = 0; +int enter_cnt = 0; +int exit_cnt = 0; + +SEC("tp_btf/sys_enter") +int BPF_PROG(on_enter, struct pt_regs *regs, long id) +{ + struct task_struct *task; + long *ptr; + + task = bpf_get_current_task_btf(); + if (task->pid != target_pid) + return 0; + + ptr = bpf_task_storage_get(&enter_id, task, 0, + BPF_LOCAL_STORAGE_GET_F_CREATE); + if (!ptr) + return 0; + + __sync_fetch_and_add(&enter_cnt, 1); + *ptr = MAGIC_VALUE + enter_cnt; + + return 0; +} + +SEC("tp_btf/sys_exit") +int BPF_PROG(on_exit, struct pt_regs *regs, long id) +{ + struct task_struct *task; + long *ptr; + + task = bpf_get_current_task_btf(); + if (task->pid != target_pid) + return 0; + + ptr = bpf_task_storage_get(&enter_id, task, 0, + BPF_LOCAL_STORAGE_GET_F_CREATE); + if (!ptr) + return 0; + + __sync_fetch_and_add(&exit_cnt, 1); + if (*ptr != MAGIC_VALUE + exit_cnt) + __sync_fetch_and_add(&mismatch_cnt, 1); + return 0; +} |