[PATCHv20 bpf-next 5/6] selftests/bpf: Add verifier tests for bpf arg ARG_CONST_MAP_PTR_OR_NULL
From: Hangbin Liu <hidden>
Date: 2021-02-23 13:02:21
Also in:
netdev
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [selftests] (test runners & infrastructure), kernel selftest framework, the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Shuah Khan, Linus Torvalds
Use helper bpf_redirect_map() and bpf_redirect_map_multi() to test bpf
arg ARG_CONST_MAP_PTR and ARG_CONST_MAP_PTR_OR_NULL. Make sure the
map arg could be verified correctly when it is NULL or valid map
pointer.
Add devmap and devmap_hash in struct bpf_test due to bpf_redirect_{map,
map_multi} limit.
Test result:
]# ./test_verifier 713 716
#713/p ARG_CONST_MAP_PTR: null pointer OK
#714/p ARG_CONST_MAP_PTR: valid map pointer OK
#715/p ARG_CONST_MAP_PTR_OR_NULL: null pointer for ex_map OK
#716/p ARG_CONST_MAP_PTR_OR_NULL: valid map pointer for ex_map OK
Summary: 4 PASSED, 0 SKIPPED, 0 FAILED
Acked-by: Toke Høiland-Jørgensen <redacted>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Hangbin Liu <redacted>
---
tools/testing/selftests/bpf/test_verifier.c | 22 +++++-
.../testing/selftests/bpf/verifier/map_ptr.c | 70 +++++++++++++++++++
2 files changed, 91 insertions(+), 1 deletion(-)
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index 58b5a349d3ba..8b474177dab0 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c@@ -50,7 +50,7 @@ #define MAX_INSNS BPF_MAXINSNS #define MAX_TEST_INSNS 1000000 #define MAX_FIXUPS 8 -#define MAX_NR_MAPS 21 +#define MAX_NR_MAPS 23 #define MAX_TEST_RUNS 8 #define POINTER_VALUE 0xcafe4all #define TEST_DATA_LEN 64
@@ -88,6 +88,8 @@ struct bpf_test { int fixup_map_event_output[MAX_FIXUPS]; int fixup_map_reuseport_array[MAX_FIXUPS]; int fixup_map_ringbuf[MAX_FIXUPS]; + int fixup_map_devmap[MAX_FIXUPS]; + int fixup_map_devmap_hash[MAX_FIXUPS]; /* Expected verifier log output for result REJECT or VERBOSE_ACCEPT. * Can be a tab-separated sequence of expected strings. An empty string * means no log verification.
@@ -718,6 +720,8 @@ static void do_test_fixup(struct bpf_test *test, enum bpf_prog_type prog_type, int *fixup_map_event_output = test->fixup_map_event_output; int *fixup_map_reuseport_array = test->fixup_map_reuseport_array; int *fixup_map_ringbuf = test->fixup_map_ringbuf; + int *fixup_map_devmap = test->fixup_map_devmap; + int *fixup_map_devmap_hash = test->fixup_map_devmap_hash; if (test->fill_helper) { test->fill_insns = calloc(MAX_TEST_INSNS, sizeof(struct bpf_insn));
@@ -903,6 +907,22 @@ static void do_test_fixup(struct bpf_test *test, enum bpf_prog_type prog_type, fixup_map_ringbuf++; } while (*fixup_map_ringbuf); } + if (*fixup_map_devmap) { + map_fds[20] = __create_map(BPF_MAP_TYPE_DEVMAP, + sizeof(u32), sizeof(u32), 1, 0); + do { + prog[*fixup_map_devmap].imm = map_fds[20]; + fixup_map_devmap++; + } while (*fixup_map_devmap); + } + if (*fixup_map_devmap_hash) { + map_fds[21] = __create_map(BPF_MAP_TYPE_DEVMAP_HASH, + sizeof(u32), sizeof(u32), 1, 0); + do { + prog[*fixup_map_devmap_hash].imm = map_fds[21]; + fixup_map_devmap_hash++; + } while (*fixup_map_devmap_hash); + } } struct libcap {
diff --git a/tools/testing/selftests/bpf/verifier/map_ptr.c b/tools/testing/selftests/bpf/verifier/map_ptr.c
index b117bdd3806d..1a532198c9c1 100644
--- a/tools/testing/selftests/bpf/verifier/map_ptr.c
+++ b/tools/testing/selftests/bpf/verifier/map_ptr.c@@ -93,3 +93,73 @@ .fixup_map_hash_16b = { 4 }, .result = ACCEPT, }, +{ + "ARG_CONST_MAP_PTR: null pointer", + .insns = { + /* bpf_redirect_map arg1 (map) */ + BPF_MOV64_IMM(BPF_REG_1, 0), + /* bpf_redirect_map arg2 (ifindex) */ + BPF_MOV64_IMM(BPF_REG_2, 0), + /* bpf_redirect_map arg3 (flags) */ + BPF_MOV64_IMM(BPF_REG_3, 0), + BPF_EMIT_CALL(BPF_FUNC_redirect_map), + BPF_EXIT_INSN(), + }, + .result = REJECT, + .prog_type = BPF_PROG_TYPE_XDP, + .errstr = "R1 type=inv expected=map_ptr", +}, +{ + "ARG_CONST_MAP_PTR: valid map pointer", + .insns = { + BPF_MOV64_IMM(BPF_REG_1, 0), + /* bpf_redirect_map arg1 (map) */ + BPF_LD_MAP_FD(BPF_REG_1, 0), + /* bpf_redirect_map arg2 (ifindex) */ + BPF_MOV64_IMM(BPF_REG_2, 0), + /* bpf_redirect_map arg3 (flags) */ + BPF_MOV64_IMM(BPF_REG_3, 0), + BPF_EMIT_CALL(BPF_FUNC_redirect_map), + BPF_EXIT_INSN(), + }, + .fixup_map_devmap = { 1 }, + .result = ACCEPT, + .prog_type = BPF_PROG_TYPE_XDP, +}, +{ + "ARG_CONST_MAP_PTR_OR_NULL: null pointer for ex_map", + .insns = { + BPF_MOV64_IMM(BPF_REG_1, 0), + /* bpf_redirect_map_multi arg1 (in_map) */ + BPF_LD_MAP_FD(BPF_REG_1, 0), + /* bpf_redirect_map_multi arg2 (ex_map) */ + BPF_MOV64_IMM(BPF_REG_2, 0), + /* bpf_redirect_map_multi arg3 (flags) */ + BPF_MOV64_IMM(BPF_REG_3, 0), + BPF_EMIT_CALL(BPF_FUNC_redirect_map_multi), + BPF_EXIT_INSN(), + }, + .fixup_map_devmap = { 1 }, + .result = ACCEPT, + .prog_type = BPF_PROG_TYPE_XDP, + .retval = 4, +}, +{ + "ARG_CONST_MAP_PTR_OR_NULL: valid map pointer for ex_map", + .insns = { + BPF_MOV64_IMM(BPF_REG_1, 0), + /* bpf_redirect_map_multi arg1 (in_map) */ + BPF_LD_MAP_FD(BPF_REG_1, 0), + /* bpf_redirect_map_multi arg2 (ex_map) */ + BPF_LD_MAP_FD(BPF_REG_2, 1), + /* bpf_redirect_map_multi arg3 (flags) */ + BPF_MOV64_IMM(BPF_REG_3, 0), + BPF_EMIT_CALL(BPF_FUNC_redirect_map_multi), + BPF_EXIT_INSN(), + }, + .fixup_map_devmap = { 1 }, + .fixup_map_devmap_hash = { 3 }, + .result = ACCEPT, + .prog_type = BPF_PROG_TYPE_XDP, + .retval = 4, +},
--
2.26.2