diff options
| -rw-r--r-- | ChangeLog | 10 | ||||
| -rw-r--r-- | bignum.c | 8 | ||||
| -rw-r--r-- | ext/bigdecimal/bigdecimal.c | 24 |
3 files changed, 40 insertions, 2 deletions
@@ -1,3 +1,13 @@ +Wed Apr 10 12:32:37 2013 Tanaka Akira <akr@fsij.org> + + * bignum.c (rb_ll2big): Don't overflow on signed integer negation. + + * ext/bigdecimal/bigdecimal.c (MUL_OVERFLOW_SIGNED_VALUE_P): New + macro. + (AddExponent): Don't overflow on signed integer multiplication. + (VpCtoV): Don't overflow on signed integer arithmetic. + (VpCtoV): Don't overflow on signed integer arithmetic. + Wed Apr 10 06:32:12 2013 Tanaka Akira <akr@fsij.org> * internal.h (MUL_OVERFLOW_INT_P): New macro. @@ -832,13 +832,17 @@ static VALUE rb_ll2big(LONG_LONG n) { long neg = 0; + unsigned LONG_LONG u; VALUE big; if (n < 0) { - n = -n; + u = 1 + (unsigned LONG_LONG)(-(n + 1)); /* u = -n avoiding overflow */ neg = 1; } - big = rb_ull2big(n); + else { + u = n; + } + big = rb_ull2big(u); if (neg) { RBIGNUM_SET_SIGN(big, 0); } diff --git a/ext/bigdecimal/bigdecimal.c b/ext/bigdecimal/bigdecimal.c index 9e2aa31d37..d6cc409eac 100644 --- a/ext/bigdecimal/bigdecimal.c +++ b/ext/bigdecimal/bigdecimal.c @@ -38,6 +38,16 @@ /* #define ENABLE_NUMERIC_STRING */ +#define MUL_OVERFLOW_SIGNED_INTEGER_P(a, b, min, max) ( \ + (a) == 0 ? 0 : \ + (a) == -1 ? (b) < -(max) : \ + (a) > 0 ? \ + ((b) > 0 ? (max) / (a) < (b) : (min) / (a) > (b)) : \ + ((b) > 0 ? (min) / (a) < (b) : (max) / (a) > (b))) +#define SIGNED_VALUE_MAX INTPTR_MAX +#define SIGNED_VALUE_MIN INTPTR_MIN +#define MUL_OVERFLOW_SIGNED_VALUE_P(a, b) MUL_OVERFLOW_SIGNED_INTEGER_P(a, b, SIGNED_VALUE_MIN, SIGNED_VALUE_MAX) + VALUE rb_cBigDecimal; VALUE rb_mBigMath; @@ -3735,12 +3745,18 @@ AddExponent(Real *a, SIGNED_VALUE n) SIGNED_VALUE eb, mb; if (e > 0) { if (n > 0) { + if (MUL_OVERFLOW_SIGNED_VALUE_P(m, (SIGNED_VALUE)BASE_FIG) || + MUL_OVERFLOW_SIGNED_VALUE_P(e, (SIGNED_VALUE)BASE_FIG)) + goto overflow; mb = m*(SIGNED_VALUE)BASE_FIG; eb = e*(SIGNED_VALUE)BASE_FIG; if (mb < eb) goto overflow; } } else if (n < 0) { + if (MUL_OVERFLOW_SIGNED_VALUE_P(m, (SIGNED_VALUE)BASE_FIG) || + MUL_OVERFLOW_SIGNED_VALUE_P(e, (SIGNED_VALUE)BASE_FIG)) + goto underflow; mb = m*(SIGNED_VALUE)BASE_FIG; eb = e*(SIGNED_VALUE)BASE_FIG; if (mb > eb) goto underflow; @@ -5254,9 +5270,17 @@ VpCtoV(Real *a, const char *int_chr, size_t ni, const char *frac, size_t nf, con ++me; } while (i < me) { + if (MUL_OVERFLOW_SIGNED_VALUE_P(e, (SIGNED_VALUE)BASE_FIG)) + goto exp_overflow; es = e * (SIGNED_VALUE)BASE_FIG; + if (MUL_OVERFLOW_SIGNED_VALUE_P(e, 10) || + SIGNED_VALUE_MAX - (exp_chr[i] - '0') < e * 10) + goto exp_overflow; e = e * 10 + exp_chr[i] - '0'; + if (MUL_OVERFLOW_SIGNED_VALUE_P(e, (SIGNED_VALUE)BASE_FIG)) + goto exp_overflow; if (es > (SIGNED_VALUE)(e * BASE_FIG)) { + exp_overflow: exponent_overflow = 1; e = es; /* keep sign */ break; |