From 7670e1fc79886d1a98e90837be4df1972a2b8e6d Mon Sep 17 00:00:00 2001 From: Maganty Rushyendra Date: Wed, 1 Jul 2020 15:13:12 +0800 Subject: [PATCH] Fix errors in overflow checks for String conversion to int Current error checks for to_int and to_int64 do not issue overflow error messages for INT64_MAX + 1, INT64_MAX + 2, and others close to the limits. Likewise, error checks for hex_to_int, hex_to_int64 and bin_to_int64 issue false positive error messages for INT64_MIN or INT32_MIN. This commit fixes these error checks. --- core/ustring.cpp | 28 ++++++++++++++-------------- 1 file changed, 14 insertions(+), 14 deletions(-) diff --git a/core/ustring.cpp b/core/ustring.cpp index 94acef09e96..8bb490064f8 100644 --- a/core/ustring.cpp +++ b/core/ustring.cpp @@ -1682,8 +1682,9 @@ int String::hex_to_int(bool p_with_prefix) const { } else { return 0; } - - ERR_FAIL_COND_V_MSG(hex > INT32_MAX / 16, sign == 1 ? INT32_MAX : INT32_MIN, "Cannot represent " + *this + " as integer, provided value is " + (sign == 1 ? "too big." : "too small.")); + // Check for overflow/underflow, with special case to ensure INT32_MIN does not result in error + bool overflow = ((hex > INT32_MAX / 16) && (sign == 1 || (sign == -1 && hex != (INT32_MAX >> 4) + 1))) || (sign == -1 && hex == (INT32_MAX >> 4) + 1 && c > '0'); + ERR_FAIL_COND_V_MSG(overflow, sign == 1 ? INT32_MAX : INT32_MIN, "Cannot represent " + *this + " as integer, provided value is " + (sign == 1 ? "too big." : "too small.")); hex *= 16; hex += n; s++; @@ -1724,8 +1725,8 @@ int64_t String::hex_to_int64(bool p_with_prefix) const { } else { return 0; } - - ERR_FAIL_COND_V_MSG(hex > INT64_MAX / 16, sign == 1 ? INT64_MAX : INT64_MIN, "Cannot represent " + *this + " as 64-bit integer, provided value is " + (sign == 1 ? "too big." : "too small.")); + bool overflow = ((hex > INT64_MAX / 16) && (sign == 1 || (sign == -1 && hex != (INT64_MAX >> 4) + 1))) || (sign == -1 && hex == (INT64_MAX >> 4) + 1 && c > '0'); + ERR_FAIL_COND_V_MSG(overflow, sign == 1 ? INT64_MAX : INT64_MIN, "Cannot represent " + *this + " as 64-bit integer, provided value is " + (sign == 1 ? "too big." : "too small.")); hex *= 16; hex += n; s++; @@ -1764,8 +1765,9 @@ int64_t String::bin_to_int64(bool p_with_prefix) const { } else { return 0; } - - ERR_FAIL_COND_V_MSG(binary > INT64_MAX / 2, sign == 1 ? INT64_MAX : INT64_MIN, "Cannot represent " + *this + " as 64-bit integer, provided value is " + (sign == 1 ? "too big." : "too small.")); + // Check for overflow/underflow, with special case to ensure INT64_MIN does not result in error + bool overflow = ((binary > INT64_MAX / 2) && (sign == 1 || (sign == -1 && binary != (INT64_MAX >> 1) + 1))) || (sign == -1 && binary == (INT64_MAX >> 1) + 1 && c > '0'); + ERR_FAIL_COND_V_MSG(overflow, sign == 1 ? INT64_MAX : INT64_MIN, "Cannot represent " + *this + " as 64-bit integer, provided value is " + (sign == 1 ? "too big." : "too small.")); binary *= 2; binary += n; s++; @@ -1788,8 +1790,8 @@ int String::to_int() const { CharType c = operator[](i); if (c >= '0' && c <= '9') { - - ERR_FAIL_COND_V_MSG(integer > INT32_MAX / 10, sign == 1 ? INT32_MAX : INT32_MIN, "Cannot represent " + *this + " as integer, provided value is " + (sign == 1 ? "too big." : "too small.")); + bool overflow = (integer > INT32_MAX / 10) || (integer == INT32_MAX / 10 && ((sign == 1 && c > '7') || (sign == -1 && c > '8'))); + ERR_FAIL_COND_V_MSG(overflow, sign == 1 ? INT32_MAX : INT32_MIN, "Cannot represent " + *this + " as integer, provided value is " + (sign == 1 ? "too big." : "too small.")); integer *= 10; integer += c - '0'; @@ -1813,16 +1815,14 @@ int64_t String::to_int64() const { int64_t sign = 1; for (int i = 0; i < to; i++) { - CharType c = operator[](i); if (c >= '0' && c <= '9') { - - ERR_FAIL_COND_V_MSG(integer > INT64_MAX / 10, sign == 1 ? INT64_MAX : INT64_MIN, "Cannot represent " + *this + " as 64-bit integer, provided value is " + (sign == 1 ? "too big." : "too small.")); + bool overflow = (integer > INT64_MAX / 10) || (integer == INT64_MAX / 10 && ((sign == 1 && c > '7') || (sign == -1 && c > '8'))); + ERR_FAIL_COND_V_MSG(overflow, sign == 1 ? INT64_MAX : INT64_MIN, "Cannot represent " + *this + " as 64-bit integer, provided value is " + (sign == 1 ? "too big." : "too small.")); integer *= 10; integer += c - '0'; } else if (integer == 0 && c == '-') { - sign = -sign; } } @@ -1847,8 +1847,8 @@ int String::to_int(const char *p_str, int p_len) { char c = p_str[i]; if (c >= '0' && c <= '9') { - - ERR_FAIL_COND_V_MSG(integer > INT32_MAX / 10, sign == 1 ? INT32_MAX : INT32_MIN, "Cannot represent " + String(p_str).substr(0, to) + " as integer, provided value is " + (sign == 1 ? "too big." : "too small.")); + bool overflow = (integer > INT32_MAX / 10) || (integer == INT32_MAX / 10 && ((sign == 1 && c > '7') || (sign == -1 && c > '8'))); + ERR_FAIL_COND_V_MSG(overflow, sign == 1 ? INT32_MAX : INT32_MIN, "Cannot represent " + String(p_str).substr(0, to) + " as integer, provided value is " + (sign == 1 ? "too big." : "too small.")); integer *= 10; integer += c - '0';