selftests/bpf: add range x range test to reg_bounds

Now that verifier supports range vs range bounds adjustments, validate
that by checking each generated range against every other generated
range, across all supported operators (everything by JSET).

We also add few cases that were problematic during development either
for verifier or for selftest's range tracking implementation.

Note that we utilize the same trick with splitting everything into
multiple independent parallelizable tests, but init_t and cond_t. This
brings down verification time in parallel mode from more than 8 hours
down to less that 1.5 hours. 106 million cases were successfully
validate for range vs range logic, in addition to about 7 million range
vs const cases, added in earlier patch.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231112010609.848406-10-andrii@kernel.orgSigned-off-by: Alexei Starovoitov <ast@kernel.org>

tools/testing/selftests/bpf/prog_tests/reg_bounds.c

@@ -1760,6 +1760,60 @@ static void validate_gen_range_vs_const_32(enum num_t init_t, enum num_t cond_t)
 	cleanup_ctx(&ctx);
 }
 
+static void validate_gen_range_vs_range(enum num_t init_t, enum num_t cond_t)
+{
+	struct ctx ctx;
+	const struct range *ranges;
+	int i, j, rcnt;
+
+	memset(&ctx, 0, sizeof(ctx));
+
+	if (prepare_gen_tests(&ctx))
+		goto cleanup;
+
+	switch (init_t)
+	{
+	case U64:
+		ranges = ctx.uranges;
+		rcnt = ctx.range_cnt;
+		break;
+	case U32:
+		ranges = ctx.usubranges;
+		rcnt = ctx.subrange_cnt;
+		break;
+	case S64:
+		ranges = ctx.sranges;
+		rcnt = ctx.range_cnt;
+		break;
+	case S32:
+		ranges = ctx.ssubranges;
+		rcnt = ctx.subrange_cnt;
+		break;
+	default:
+		printf("validate_gen_range_vs_range!\n");
+		exit(1);
+	}
+
+	ctx.total_case_cnt = (MAX_OP - MIN_OP + 1) * (2 * rcnt * (rcnt + 1) / 2);
+	ctx.start_ns = get_time_ns();
+	snprintf(ctx.progress_ctx, sizeof(ctx.progress_ctx),
+		 "RANGE x RANGE, %s -> %s",
+		 t_str(init_t), t_str(cond_t));
+
+	for (i = 0; i < rcnt; i++) {
+		for (j = i; j < rcnt; j++) {
+			/* (<range> x <range>) */
+			if (verify_case(&ctx, init_t, cond_t, ranges[i], ranges[j]))
+				goto cleanup;
+			if (verify_case(&ctx, init_t, cond_t, ranges[j], ranges[i]))
+				goto cleanup;
+		}
+	}
+
+cleanup:
+	cleanup_ctx(&ctx);
+}
+
 /* Go over thousands of test cases generated from initial seed values.
  * Given this take a long time, guard this begind SLOW_TESTS=1 envvar. If
  * envvar is not set, this test is skipped during test_progs testing.
@@ -1790,6 +1844,27 @@ void test_reg_bounds_gen_consts_s32_s64(void) { validate_gen_range_vs_const_32(S
 void test_reg_bounds_gen_consts_s32_u32(void) { validate_gen_range_vs_const_32(S32, U32); }
 void test_reg_bounds_gen_consts_s32_s32(void) { validate_gen_range_vs_const_32(S32, S32); }
 
+/* RANGE x RANGE, U64 initial range */
+void test_reg_bounds_gen_ranges_u64_u64(void) { validate_gen_range_vs_range(U64, U64); }
+void test_reg_bounds_gen_ranges_u64_s64(void) { validate_gen_range_vs_range(U64, S64); }
+void test_reg_bounds_gen_ranges_u64_u32(void) { validate_gen_range_vs_range(U64, U32); }
+void test_reg_bounds_gen_ranges_u64_s32(void) { validate_gen_range_vs_range(U64, S32); }
+/* RANGE x RANGE, S64 initial range */
+void test_reg_bounds_gen_ranges_s64_u64(void) { validate_gen_range_vs_range(S64, U64); }
+void test_reg_bounds_gen_ranges_s64_s64(void) { validate_gen_range_vs_range(S64, S64); }
+void test_reg_bounds_gen_ranges_s64_u32(void) { validate_gen_range_vs_range(S64, U32); }
+void test_reg_bounds_gen_ranges_s64_s32(void) { validate_gen_range_vs_range(S64, S32); }
+/* RANGE x RANGE, U32 initial range */
+void test_reg_bounds_gen_ranges_u32_u64(void) { validate_gen_range_vs_range(U32, U64); }
+void test_reg_bounds_gen_ranges_u32_s64(void) { validate_gen_range_vs_range(U32, S64); }
+void test_reg_bounds_gen_ranges_u32_u32(void) { validate_gen_range_vs_range(U32, U32); }
+void test_reg_bounds_gen_ranges_u32_s32(void) { validate_gen_range_vs_range(U32, S32); }
+/* RANGE x RANGE, S32 initial range */
+void test_reg_bounds_gen_ranges_s32_u64(void) { validate_gen_range_vs_range(S32, U64); }
+void test_reg_bounds_gen_ranges_s32_s64(void) { validate_gen_range_vs_range(S32, S64); }
+void test_reg_bounds_gen_ranges_s32_u32(void) { validate_gen_range_vs_range(S32, U32); }
+void test_reg_bounds_gen_ranges_s32_s32(void) { validate_gen_range_vs_range(S32, S32); }
+
 /* A set of hard-coded "interesting" cases to validate as part of normal
  * test_progs test runs
  */
@@ -1803,6 +1878,12 @@ static struct subtest_case crafted_cases[] = {
 	{U64, U64, {0x100000000ULL, 0x1fffffffeULL}, {0, 0}},
 	{U64, U64, {0x100000001ULL, 0x1000000ffULL}, {0, 0}},
 
+	/* single point overlap, interesting BPF_EQ and BPF_NE interactions */
+	{U64, U64, {0, 1}, {1, 0x80000000}},
+	{U64, S64, {0, 1}, {1, 0x80000000}},
+	{U64, U32, {0, 1}, {1, 0x80000000}},
+	{U64, S32, {0, 1}, {1, 0x80000000}},
+
 	{U64, S64, {0, 0xffffffff00000000ULL}, {0, 0}},
 	{U64, S64, {0x7fffffffffffffffULL, 0xffffffff00000000ULL}, {0, 0}},
 	{U64, S64, {0x7fffffff00000001ULL, 0xffffffff00000000ULL}, {0, 0}},
@@ -1837,6 +1918,11 @@ static struct subtest_case crafted_cases[] = {
 	{U32, U32, {1, U32_MAX}, {0, 0}},
 
 	{U32, S32, {0, U32_MAX}, {U32_MAX, U32_MAX}},
+
+	{S32, U64, {(u32)(s32)S32_MIN, (u32)(s32)S32_MIN}, {(u32)(s32)-255, 0}},
+	{S32, S64, {(u32)(s32)S32_MIN, (u32)(s32)-255}, {(u32)(s32)-2, 0}},
+	{S32, S64, {0, 1}, {(u32)(s32)S32_MIN, (u32)(s32)S32_MIN}},
+	{S32, U32, {(u32)(s32)S32_MIN, (u32)(s32)S32_MIN}, {(u32)(s32)S32_MIN, (u32)(s32)S32_MIN}},
 };
 
 /* Go over crafted hard-coded cases. This is fast, so we do it as part of