selftests/bpf: two scale tests

Add two tests to check that sequence of 1024 jumps is verifiable.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index e2ebcaddbe7899eae4ffcd11473717b1bc15b545..6cb6a1074fd16e05ddcc31ab4febfd2e642f01ca 100644 (file)
--- 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 (file)
index 0000000..7f868d4
--- /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,
+},