From d15f6e379c1a05164ef055dbd5a83f5190f101a5 Mon Sep 17 00:00:00 2001
From: Simon McVittie <[EMAIL REDACTED]>
Date: Mon, 9 May 2022 18:19:21 +0100
Subject: [PATCH] test: Add a unit test for overflow detection
Signed-off-by: Simon McVittie <smcv@collabora.com>
---
test/testautomation_stdlib.c | 172 ++++++++++++++++++++++++++++++++++-
1 file changed, 171 insertions(+), 1 deletion(-)
diff --git a/test/testautomation_stdlib.c b/test/testautomation_stdlib.c
index bfc8ad373dd..4c978fa9b81 100644
--- a/test/testautomation_stdlib.c
+++ b/test/testautomation_stdlib.c
@@ -322,6 +322,168 @@ stdlib_sscanf(void *arg)
return TEST_COMPLETED;
}
+#if defined(_WIN64)
+# define SIZE_FORMAT "I64u"
+#elif defined(__WIN32__)
+# define SIZE_FORMAT "I32u"
+#else
+# define SIZE_FORMAT "zu"
+#endif
+
+typedef struct
+{
+ size_t a;
+ size_t b;
+ size_t result;
+ int status;
+} overflow_test;
+
+static const overflow_test multiplications[] =
+{
+ { 1, 1, 1, 0 },
+ { 0, 0, 0, 0 },
+ { SDL_SIZE_MAX, 0, 0, 0 },
+ { SDL_SIZE_MAX, 1, SDL_SIZE_MAX, 0 },
+ { SDL_SIZE_MAX / 2, 2, SDL_SIZE_MAX - (SDL_SIZE_MAX % 2), 0 },
+ { SDL_SIZE_MAX / 23, 23, SDL_SIZE_MAX - (SDL_SIZE_MAX % 23), 0 },
+
+ { (SDL_SIZE_MAX / 2) + 1, 2, 0, -1 },
+ { (SDL_SIZE_MAX / 23) + 42, 23, 0, -1 },
+ { SDL_SIZE_MAX, SDL_SIZE_MAX, 0, -1 },
+};
+
+static const overflow_test additions[] =
+{
+ { 1, 1, 2, 0 },
+ { 0, 0, 0, 0 },
+ { SDL_SIZE_MAX, 0, SDL_SIZE_MAX, 0 },
+ { SDL_SIZE_MAX - 1, 1, SDL_SIZE_MAX, 0 },
+ { SDL_SIZE_MAX - 42, 23, SDL_SIZE_MAX - (42 - 23), 0 },
+
+ { SDL_SIZE_MAX, 1, 0, -1 },
+ { SDL_SIZE_MAX, 23, 0, -1 },
+ { SDL_SIZE_MAX, SDL_SIZE_MAX, 0, -1 },
+};
+
+static int
+stdlib_overflow(void *arg)
+{
+ size_t i;
+ size_t useBuiltin;
+
+ for (useBuiltin = 0; useBuiltin < 2; useBuiltin++) {
+ if (useBuiltin) {
+ SDLTest_Log("Using gcc/clang builtins if possible");
+ } else {
+ SDLTest_Log("Not using gcc/clang builtins");
+ }
+
+ for (i = 0; i < SDL_arraysize(multiplications); i++) {
+ const overflow_test *t = &multiplications[i];
+ int status;
+ size_t result = ~t->result;
+
+ if (useBuiltin) {
+ status = SDL_size_mul_overflow(t->a, t->b, &result);
+ } else {
+ /* This disables the macro that tries to use a gcc/clang
+ * builtin, so we test the fallback implementation instead. */
+ status = (SDL_size_mul_overflow)(t->a, t->b, &result);
+ }
+
+ if (t->status == 0) {
+ SDLTest_AssertCheck(status == 0,
+ "(%" SIZE_FORMAT " * %" SIZE_FORMAT ") should succeed",
+ t->a, t->b);
+ SDLTest_AssertCheck(result == t->result,
+ "(%" SIZE_FORMAT " * %" SIZE_FORMAT "): expected %" SIZE_FORMAT ", got %" SIZE_FORMAT,
+ t->a, t->b, t->result, result);
+ } else {
+ SDLTest_AssertCheck(status == -1,
+ "(%" SIZE_FORMAT " * %" SIZE_FORMAT ") should fail",
+ t->a, t->b);
+ }
+
+ if (t->a == t->b) {
+ continue;
+ }
+
+ result = ~t->result;
+
+ if (useBuiltin) {
+ status = SDL_size_mul_overflow(t->b, t->a, &result);
+ } else {
+ status = (SDL_size_mul_overflow)(t->b, t->a, &result);
+ }
+
+ if (t->status == 0) {
+ SDLTest_AssertCheck(status == 0,
+ "(%" SIZE_FORMAT " * %" SIZE_FORMAT ") should succeed",
+ t->b, t->a);
+ SDLTest_AssertCheck(result == t->result,
+ "(%" SIZE_FORMAT " * %" SIZE_FORMAT "): expected %" SIZE_FORMAT ", got %" SIZE_FORMAT,
+ t->b, t->a, t->result, result);
+ } else {
+ SDLTest_AssertCheck(status == -1,
+ "(%" SIZE_FORMAT " * %" SIZE_FORMAT ") should fail",
+ t->b, t->a);
+ }
+ }
+
+ for (i = 0; i < SDL_arraysize(additions); i++) {
+ const overflow_test *t = &additions[i];
+ int status;
+ size_t result = ~t->result;
+
+ if (useBuiltin) {
+ status = SDL_size_add_overflow(t->a, t->b, &result);
+ } else {
+ status = (SDL_size_add_overflow)(t->a, t->b, &result);
+ }
+
+ if (t->status == 0) {
+ SDLTest_AssertCheck(status == 0,
+ "(%" SIZE_FORMAT " + %" SIZE_FORMAT ") should succeed",
+ t->a, t->b);
+ SDLTest_AssertCheck(result == t->result,
+ "(%" SIZE_FORMAT " + %" SIZE_FORMAT "): expected %" SIZE_FORMAT ", got %" SIZE_FORMAT,
+ t->a, t->b, t->result, result);
+ } else {
+ SDLTest_AssertCheck(status == -1,
+ "(%" SIZE_FORMAT " + %" SIZE_FORMAT ") should fail",
+ t->a, t->b);
+ }
+
+ if (t->a == t->b) {
+ continue;
+ }
+
+ result = ~t->result;
+
+ if (useBuiltin) {
+ status = SDL_size_add_overflow(t->b, t->a, &result);
+ } else {
+ status = (SDL_size_add_overflow)(t->b, t->a, &result);
+ }
+
+ if (t->status == 0) {
+ SDLTest_AssertCheck(status == 0,
+ "(%" SIZE_FORMAT " + %" SIZE_FORMAT ") should succeed",
+ t->b, t->a);
+ SDLTest_AssertCheck(result == t->result,
+ "(%" SIZE_FORMAT " + %" SIZE_FORMAT "): expected %" SIZE_FORMAT ", got %" SIZE_FORMAT,
+ t->b, t->a, t->result, result);
+ } else {
+ SDLTest_AssertCheck(status == -1,
+ "(%" SIZE_FORMAT " + %" SIZE_FORMAT ") should fail",
+ t->b, t->a);
+ }
+ }
+ }
+
+ return TEST_COMPLETED;
+}
+
/* ================= Test References ================== */
/* Standard C routine test cases */
@@ -337,9 +499,17 @@ static const SDLTest_TestCaseReference stdlibTest3 =
static const SDLTest_TestCaseReference stdlibTest4 =
{ (SDLTest_TestCaseFp)stdlib_sscanf, "stdlib_sscanf", "Call to SDL_sscanf", TEST_ENABLED };
+static const SDLTest_TestCaseReference stdlibTestOverflow =
+ { stdlib_overflow, "stdlib_overflow", "Overflow detection", TEST_ENABLED };
+
/* Sequence of Standard C routine test cases */
static const SDLTest_TestCaseReference *stdlibTests[] = {
- &stdlibTest1, &stdlibTest2, &stdlibTest3, &stdlibTest4, NULL
+ &stdlibTest1,
+ &stdlibTest2,
+ &stdlibTest3,
+ &stdlibTest4,
+ &stdlibTestOverflow,
+ NULL
};
/* Standard C routine test suite (global) */