crypto/bn/bn_gcd.c:375: error: INTEGER_OVERFLOW_L2
  ([0, +oo] - 1):unsigned64 by call to `BN_usub`.
Showing all 7 steps of the trace


crypto/bn/bn_gcd.c:274:5: Call
272.           goto err;
273.   
274.       BN_one(X);
           ^
275.       BN_zero(Y);
276.       if (BN_copy(B, a) == NULL)

crypto/bn/bn_lib.c:530:1: Parameter `*a->d`
  528.   }
  529.   
  530. > int BN_set_word(BIGNUM *a, BN_ULONG w)
  531.   {
  532.       bn_check_top(a);

crypto/bn/bn_gcd.c:375:22: Call
373.                    * actually makes the algorithm slower
374.                    */
375.                   if (!BN_usub(B, B, A))
                            ^
376.                       goto err;
377.               } else {

crypto/bn/bn_add.c:166:1: <LHS trace>
164.   
165.   /* unsigned subtraction of b from a, a must be larger than b. */
166. > int BN_usub(BIGNUM *r, const BIGNUM *a, const BIGNUM *b)
167.   {
168.       int max, min, dif;

crypto/bn/bn_add.c:166:1: Parameter `*a->d`
  164.   
  165.   /* unsigned subtraction of b from a, a must be larger than b. */
  166. > int BN_usub(BIGNUM *r, const BIGNUM *a, const BIGNUM *b)
  167.   {
  168.       int max, min, dif;

crypto/bn/bn_add.c:218:13: Assignment
  216.           while (dif) {
  217.               dif--;
  218.               t1 = *(ap++);
                     ^
  219.               t2 = (t1 - 1) & BN_MASK2;
  220.               *(rp++) = t2;

crypto/bn/bn_add.c:219:13: Binary operation: ([0, +oo] - 1):unsigned64 by call to `BN_usub` 
  217.               dif--;
  218.               t1 = *(ap++);
  219.               t2 = (t1 - 1) & BN_MASK2;
                     ^
  220.               *(rp++) = t2;
  221.               if (t1)

int BN_usub(BIGNUM *r, const BIGNUM *a, const BIGNUM *b)
{
    int max, min, dif;
    register BN_ULONG t1, t2, *rp;
    register const BN_ULONG *ap, *bp;
    int i, carry;
    bn_check_top(a);
    bn_check_top(b);
    max = a->top;
    min = b->top;
    dif = max - min;
    if (dif < 0) {
        BNerr(BN_F_BN_USUB, BN_R_ARG2_LT_ARG3);
        return (0);
    }
    if (bn_wexpand(r, max) == NULL)
        return (0);
    ap = a->d;
    bp = b->d;
    rp = r->d;
#if 1
    carry = 0;
    for (i = min; i != 0; i--) {
        t1 = *(ap++);
        t2 = *(bp++);
        if (carry) {
            carry = (t1 <= t2);
            t1 = (t1 - t2 - 1) & BN_MASK2;
        } else {
            carry = (t1 < t2);
            t1 = (t1 - t2) & BN_MASK2;
        }
        *(rp++) = t1 & BN_MASK2;
    }
#else
    carry = bn_sub_words(rp, ap, bp, min);
    ap += min;
    bp += min;
    rp += min;
#endif
    if (carry) {
        if (!dif)
            return 0;
        while (dif) {
            dif--;
            t1 = *(ap++);
            t2 = (t1 - 1) & BN_MASK2;
            *(rp++) = t2;
            if (t1)
                break;
        }
    }
    if (dif && ap != rp)
        memcpy(rp, ap, sizeof(*rp) * dif);
    r->top = max;
    r->neg = 0;
    bn_correct_top(r);
    return (1);
}
['BIGNUM *int_bn_mod_inverse(BIGNUM *in,\n                           const BIGNUM *a, const BIGNUM *n, BN_CTX *ctx,\n                           int *pnoinv)\n{\n    BIGNUM *A, *B, *X, *Y, *M, *D, *T, *R = NULL;\n    BIGNUM *ret = NULL;\n    int sign;\n    if (pnoinv)\n        *pnoinv = 0;\n    if ((BN_get_flags(a, BN_FLG_CONSTTIME) != 0)\n        || (BN_get_flags(n, BN_FLG_CONSTTIME) != 0)) {\n        return BN_mod_inverse_no_branch(in, a, n, ctx);\n    }\n    bn_check_top(a);\n    bn_check_top(n);\n    BN_CTX_start(ctx);\n    A = BN_CTX_get(ctx);\n    B = BN_CTX_get(ctx);\n    X = BN_CTX_get(ctx);\n    D = BN_CTX_get(ctx);\n    M = BN_CTX_get(ctx);\n    Y = BN_CTX_get(ctx);\n    T = BN_CTX_get(ctx);\n    if (T == NULL)\n        goto err;\n    if (in == NULL)\n        R = BN_new();\n    else\n        R = in;\n    if (R == NULL)\n        goto err;\n    BN_one(X);\n    BN_zero(Y);\n    if (BN_copy(B, a) == NULL)\n        goto err;\n    if (BN_copy(A, n) == NULL)\n        goto err;\n    A->neg = 0;\n    if (B->neg || (BN_ucmp(B, A) >= 0)) {\n        if (!BN_nnmod(B, B, A, ctx))\n            goto err;\n    }\n    sign = -1;\n    if (BN_is_odd(n) && (BN_num_bits(n) <= (BN_BITS <= 32 ? 450 : 2048))) {\n        int shift;\n        while (!BN_is_zero(B)) {\n            shift = 0;\n            while (!BN_is_bit_set(B, shift)) {\n                shift++;\n                if (BN_is_odd(X)) {\n                    if (!BN_uadd(X, X, n))\n                        goto err;\n                }\n                if (!BN_rshift1(X, X))\n                    goto err;\n            }\n            if (shift > 0) {\n                if (!BN_rshift(B, B, shift))\n                    goto err;\n            }\n            shift = 0;\n            while (!BN_is_bit_set(A, shift)) {\n                shift++;\n                if (BN_is_odd(Y)) {\n                    if (!BN_uadd(Y, Y, n))\n                        goto err;\n                }\n                if (!BN_rshift1(Y, Y))\n                    goto err;\n            }\n            if (shift > 0) {\n                if (!BN_rshift(A, A, shift))\n                    goto err;\n            }\n            if (BN_ucmp(B, A) >= 0) {\n                if (!BN_uadd(X, X, Y))\n                    goto err;\n                if (!BN_usub(B, B, A))\n                    goto err;\n            } else {\n                if (!BN_uadd(Y, Y, X))\n                    goto err;\n                if (!BN_usub(A, A, B))\n                    goto err;\n            }\n        }\n    } else {\n        while (!BN_is_zero(B)) {\n            BIGNUM *tmp;\n            if (BN_num_bits(A) == BN_num_bits(B)) {\n                if (!BN_one(D))\n                    goto err;\n                if (!BN_sub(M, A, B))\n                    goto err;\n            } else if (BN_num_bits(A) == BN_num_bits(B) + 1) {\n                if (!BN_lshift1(T, B))\n                    goto err;\n                if (BN_ucmp(A, T) < 0) {\n                    if (!BN_one(D))\n                        goto err;\n                    if (!BN_sub(M, A, B))\n                        goto err;\n                } else {\n                    if (!BN_sub(M, A, T))\n                        goto err;\n                    if (!BN_add(D, T, B))\n                        goto err;\n                    if (BN_ucmp(A, D) < 0) {\n                        if (!BN_set_word(D, 2))\n                            goto err;\n                    } else {\n                        if (!BN_set_word(D, 3))\n                            goto err;\n                        if (!BN_sub(M, M, B))\n                            goto err;\n                    }\n                }\n            } else {\n                if (!BN_div(D, M, A, B, ctx))\n                    goto err;\n            }\n            tmp = A;\n            A = B;\n            B = M;\n            if (BN_is_one(D)) {\n                if (!BN_add(tmp, X, Y))\n                    goto err;\n            } else {\n                if (BN_is_word(D, 2)) {\n                    if (!BN_lshift1(tmp, X))\n                        goto err;\n                } else if (BN_is_word(D, 4)) {\n                    if (!BN_lshift(tmp, X, 2))\n                        goto err;\n                } else if (D->top == 1) {\n                    if (!BN_copy(tmp, X))\n                        goto err;\n                    if (!BN_mul_word(tmp, D->d[0]))\n                        goto err;\n                } else {\n                    if (!BN_mul(tmp, D, X, ctx))\n                        goto err;\n                }\n                if (!BN_add(tmp, tmp, Y))\n                    goto err;\n            }\n            M = Y;\n            Y = X;\n            X = tmp;\n            sign = -sign;\n        }\n    }\n    if (sign < 0) {\n        if (!BN_sub(Y, n, Y))\n            goto err;\n    }\n    if (BN_is_one(A)) {\n        if (!Y->neg && BN_ucmp(Y, n) < 0) {\n            if (!BN_copy(R, Y))\n                goto err;\n        } else {\n            if (!BN_nnmod(R, Y, n, ctx))\n                goto err;\n        }\n    } else {\n        if (pnoinv)\n            *pnoinv = 1;\n        goto err;\n    }\n    ret = R;\n err:\n    if ((ret == NULL) && (in == NULL))\n        BN_free(R);\n    BN_CTX_end(ctx);\n    bn_check_top(ret);\n    return (ret);\n}', 'int BN_set_word(BIGNUM *a, BN_ULONG w)\n{\n    bn_check_top(a);\n    if (bn_expand(a, (int)sizeof(BN_ULONG) * 8) == NULL)\n        return (0);\n    a->neg = 0;\n    a->d[0] = w;\n    a->top = (w ? 1 : 0);\n    bn_check_top(a);\n    return (1);\n}', 'int BN_usub(BIGNUM *r, const BIGNUM *a, const BIGNUM *b)\n{\n    int max, min, dif;\n    register BN_ULONG t1, t2, *rp;\n    register const BN_ULONG *ap, *bp;\n    int i, carry;\n    bn_check_top(a);\n    bn_check_top(b);\n    max = a->top;\n    min = b->top;\n    dif = max - min;\n    if (dif < 0) {\n        BNerr(BN_F_BN_USUB, BN_R_ARG2_LT_ARG3);\n        return (0);\n    }\n    if (bn_wexpand(r, max) == NULL)\n        return (0);\n    ap = a->d;\n    bp = b->d;\n    rp = r->d;\n#if 1\n    carry = 0;\n    for (i = min; i != 0; i--) {\n        t1 = *(ap++);\n        t2 = *(bp++);\n        if (carry) {\n            carry = (t1 <= t2);\n            t1 = (t1 - t2 - 1) & BN_MASK2;\n        } else {\n            carry = (t1 < t2);\n            t1 = (t1 - t2) & BN_MASK2;\n        }\n        *(rp++) = t1 & BN_MASK2;\n    }\n#else\n    carry = bn_sub_words(rp, ap, bp, min);\n    ap += min;\n    bp += min;\n    rp += min;\n#endif\n    if (carry) {\n        if (!dif)\n            return 0;\n        while (dif) {\n            dif--;\n            t1 = *(ap++);\n            t2 = (t1 - 1) & BN_MASK2;\n            *(rp++) = t2;\n            if (t1)\n                break;\n        }\n    }\n    if (dif && ap != rp)\n        memcpy(rp, ap, sizeof(*rp) * dif);\n    r->top = max;\n    r->neg = 0;\n    bn_correct_top(r);\n    return (1);\n}']