From ee2eb063d330dc8dbe71041a1dae3cea889fdcb5 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Tue, 8 Oct 2019 10:59:42 -0700 Subject: [PATCH] selftests/bpf: Add BPF_CORE_READ and BPF_CORE_READ_STR_INTO macro tests Validate BPF_CORE_READ correctness and handling of up to 9 levels of nestedness using cyclic task->(group_leader->)*->tgid chains. Also add a test of maximum-dpeth BPF_CORE_READ_STR_INTO() macro. Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Acked-by: John Fastabend Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20191008175942.1769476-8-andriin@fb.com --- .../testing/selftests/bpf/prog_tests/core_reloc.c | 8 +++- .../testing/selftests/bpf/progs/core_reloc_types.h | 9 ++++ .../selftests/bpf/progs/test_core_reloc_kernel.c | 54 +++++++++++++++++++++- 3 files changed, 68 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/bpf/prog_tests/core_reloc.c b/tools/testing/selftests/bpf/prog_tests/core_reloc.c index f3863f9..21a0dff 100644 --- a/tools/testing/selftests/bpf/prog_tests/core_reloc.c +++ b/tools/testing/selftests/bpf/prog_tests/core_reloc.c @@ -193,8 +193,12 @@ static struct core_reloc_test_case test_cases[] = { .btf_src_file = NULL, /* load from /lib/modules/$(uname -r) */ .input = "", .input_len = 0, - .output = "\1", /* true */ - .output_len = 1, + .output = STRUCT_TO_CHAR_PTR(core_reloc_kernel_output) { + .valid = { 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, }, + .comm = "test_progs\0\0\0\0\0", + .comm_len = 11, + }, + .output_len = sizeof(struct core_reloc_kernel_output), }, /* validate BPF program can use multiple flavors to match against diff --git a/tools/testing/selftests/bpf/progs/core_reloc_types.h b/tools/testing/selftests/bpf/progs/core_reloc_types.h index f686a81..9a6bdeb 100644 --- a/tools/testing/selftests/bpf/progs/core_reloc_types.h +++ b/tools/testing/selftests/bpf/progs/core_reloc_types.h @@ -1,5 +1,14 @@ #include #include +/* + * KERNEL + */ + +struct core_reloc_kernel_output { + int valid[10]; + char comm[16]; + int comm_len; +}; /* * FLAVORS diff --git a/tools/testing/selftests/bpf/progs/test_core_reloc_kernel.c b/tools/testing/selftests/bpf/progs/test_core_reloc_kernel.c index 14ce688..50f6096 100644 --- a/tools/testing/selftests/bpf/progs/test_core_reloc_kernel.c +++ b/tools/testing/selftests/bpf/progs/test_core_reloc_kernel.c @@ -13,9 +13,17 @@ static volatile struct data { char out[256]; } data; +struct core_reloc_kernel_output { + int valid[10]; + char comm[16]; + int comm_len; +}; + struct task_struct { int pid; int tgid; + char comm[16]; + struct task_struct *group_leader; }; #define CORE_READ(dst, src) bpf_core_read(dst, sizeof(*(dst)), src) @@ -24,7 +32,9 @@ SEC("raw_tracepoint/sys_enter") int test_core_kernel(void *ctx) { struct task_struct *task = (void *)bpf_get_current_task(); + struct core_reloc_kernel_output *out = (void *)&data.out; uint64_t pid_tgid = bpf_get_current_pid_tgid(); + uint32_t real_tgid = (uint32_t)pid_tgid; int pid, tgid; if (CORE_READ(&pid, &task->pid) || @@ -32,7 +42,49 @@ int test_core_kernel(void *ctx) return 1; /* validate pid + tgid matches */ - data.out[0] = (((uint64_t)pid << 32) | tgid) == pid_tgid; + out->valid[0] = (((uint64_t)pid << 32) | tgid) == pid_tgid; + + /* test variadic BPF_CORE_READ macros */ + out->valid[1] = BPF_CORE_READ(task, + tgid) == real_tgid; + out->valid[2] = BPF_CORE_READ(task, + group_leader, + tgid) == real_tgid; + out->valid[3] = BPF_CORE_READ(task, + group_leader, group_leader, + tgid) == real_tgid; + out->valid[4] = BPF_CORE_READ(task, + group_leader, group_leader, group_leader, + tgid) == real_tgid; + out->valid[5] = BPF_CORE_READ(task, + group_leader, group_leader, group_leader, + group_leader, + tgid) == real_tgid; + out->valid[6] = BPF_CORE_READ(task, + group_leader, group_leader, group_leader, + group_leader, group_leader, + tgid) == real_tgid; + out->valid[7] = BPF_CORE_READ(task, + group_leader, group_leader, group_leader, + group_leader, group_leader, group_leader, + tgid) == real_tgid; + out->valid[8] = BPF_CORE_READ(task, + group_leader, group_leader, group_leader, + group_leader, group_leader, group_leader, + group_leader, + tgid) == real_tgid; + out->valid[9] = BPF_CORE_READ(task, + group_leader, group_leader, group_leader, + group_leader, group_leader, group_leader, + group_leader, group_leader, + tgid) == real_tgid; + + /* test BPF_CORE_READ_STR_INTO() returns correct code and contents */ + out->comm_len = BPF_CORE_READ_STR_INTO( + &out->comm, task, + group_leader, group_leader, group_leader, group_leader, + group_leader, group_leader, group_leader, group_leader, + comm); return 0; } -- 2.7.4