Add two tests to check that sequence of 1024 jumps is verifiable.
Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>
---
tools/testing/selftests/bpf/test_verifier.c | 70 ++++++++++++++++++++
tools/testing/selftests/bpf/verifier/scale.c | 18 +++++
2 files changed, 88 insertions(+)
create mode 100644 tools/testing/selftests/bpf/verifier/scale.c
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index e2ebcaddbe78..6cb6a1074fd1 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -208,6 +208,76 @@ static void bpf_fill_rand_ld_dw(struct bpf_test *self)
self->retval = (uint32_t)res;
}
+/* test the sequence of 1k jumps */
+static void bpf_fill_scale1(struct bpf_test *self)
+{
+ struct bpf_insn *insn = self->fill_insns;
+ int i = 0, k = 0;
+
+ insn[i++] = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
+ /* test to check that the sequence of 1024 jumps is acceptable */
+ while (k++ < 1024) {
+ insn[i++] = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
+ BPF_FUNC_get_prandom_u32);
+ insn[i++] = BPF_JMP_IMM(BPF_JGT, BPF_REG_0, bpf_semi_rand_get(), 2);
+ insn[i++] = BPF_MOV64_REG(BPF_REG_1, BPF_REG_10);
+ insn[i++] = BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_6,
+ -8 * (k % 64 + 1));
+ }
+ /* every jump adds 1024 steps to insn_processed, so to stay exactly
+ * within 1m limit add MAX_TEST_INSNS - 1025 MOVs and 1 EXIT
+ */
+ while (i < MAX_TEST_INSNS - 1025)
+ insn[i++] = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, 42);
+ insn[i] = BPF_EXIT_INSN();
+ self->prog_len = i + 1;
+ self->retval = 42;
+}
+
+/* test the sequence of 1k jumps in inner most function (function depth 8)*/
+static void bpf_fill_scale2(struct bpf_test *self)
+{
+ struct bpf_insn *insn = self->fill_insns;
+ int i = 0, k = 0;
+
+#define FUNC_NEST 7
+ for (k = 0; k < FUNC_NEST; k++) {
+ insn[i++] = BPF_CALL_REL(1);
+ insn[i++] = BPF_EXIT_INSN();
+ }
+ insn[i++] = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
+ /* test to check that the sequence of 1024 jumps is acceptable */
+ while (k++ < 1024) {
+ insn[i++] = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
+ BPF_FUNC_get_prandom_u32);
+ insn[i++] = BPF_JMP_IMM(BPF_JGT, BPF_REG_0, bpf_semi_rand_get(), 2);
+ insn[i++] = BPF_MOV64_REG(BPF_REG_1, BPF_REG_10);
+ insn[i++] = BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_6,
+ -8 * (k % (64 - 4 * FUNC_NEST) + 1));
+ }
+ /* every jump adds 1024 steps to insn_processed, so to stay exactly
+ * within 1m limit add MAX_TEST_INSNS - 1025 MOVs and 1 EXIT
+ */
+ while (i < MAX_TEST_INSNS - 1025)
+ insn[i++] = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, 42);
+ insn[i] = BPF_EXIT_INSN();
+ self->prog_len = i + 1;
+ self->retval = 42;
+}
+
+static void bpf_fill_scale(struct bpf_test *self)
+{
+ switch (self->retval) {
+ case 1:
+ return bpf_fill_scale1(self);
+ case 2:
+ return bpf_fill_scale2(self);
+ default:
+ self->prog_len = 0;
+ break;
+ }
+}
+
/* BPF_SK_LOOKUP contains 13 instructions, if you need to fix up maps */
#define BPF_SK_LOOKUP(func) \
/* struct bpf_sock_tuple tuple = {} */ \
diff --git a/tools/testing/selftests/bpf/verifier/scale.c b/tools/testing/selftests/bpf/verifier/scale.c
new file mode 100644
index 000000000000..7f868d4802e0
--- /dev/null
+++ b/tools/testing/selftests/bpf/verifier/scale.c
@@ -0,0 +1,18 @@
+{
+ "scale: scale test 1",
+ .insns = { },
+ .data = { },
+ .fill_helper = bpf_fill_scale,
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .result = ACCEPT,
+ .retval = 1,
+},
+{
+ "scale: scale test 2",
+ .insns = { },
+ .data = { },
+ .fill_helper = bpf_fill_scale,
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .result = ACCEPT,
+ .retval = 2,
+},
--
2.20.0
