test/bntest.c:1802: error: BUFFER_OVERRUN_L3
  Offset: [1, +oo] Size: [0, 8388607] by call to `BN_div`.
Showing all 14 steps of the trace


test/bntest.c:1779:10: Call
1777.   
1778.       /* Test that BN_mul never gives negative zero. */
1779.       if (!TEST_true(BN_set_word(a, 1)))
                 ^
1780.           goto err;
1781.       BN_set_negative(a, 1);

crypto/bn/bn_lib.c:387:1: Parameter `*a->d`
  385.   }
  386.   
  387. > int BN_set_word(BIGNUM *a, BN_ULONG w)
  388.   {
  389.       bn_check_top(a);

crypto/bn/bn_lib.c:390:9: Call
  388.   {
  389.       bn_check_top(a);
  390.       if (bn_expand(a, (int)sizeof(BN_ULONG) * 8) == NULL)
                 ^
  391.           return 0;
  392.       a->neg = 0;

crypto/bn/bn_lcl.h:651:1: Parameter `*a->d`
    649.                            const BIGNUM *add, const BIGNUM *rem, BN_CTX *ctx);
    650.   
    651. > static ossl_inline BIGNUM *bn_expand(BIGNUM *a, int bits)
    652.   {
    653.       if (bits > (INT_MAX - BN_BITS2 + 1))

test/bntest.c:1802:14: Call
1800.               goto err;
1801.           BN_set_negative(numerator, 1);
1802.           if (!TEST_true(BN_div(a, b, numerator, denominator, ctx))
                     ^
1803.                   || !TEST_BN_eq_zero(a)
1804.                   || !TEST_BN_ge_zero(a))

crypto/bn/bn_div.c:137:1: Parameter `*dv->d`
  135.    * If 'dv' or 'rm' is NULL, the respective value is not returned.
  136.    */
  137. > int BN_div(BIGNUM *dv, BIGNUM *rm, const BIGNUM *num, const BIGNUM *divisor,
  138.              BN_CTX *ctx)
  139.   {

crypto/bn/bn_div.c:251:10: Call
  249.   
  250.       /* Setup to 'res' */
  251.       if (!bn_wexpand(res, (loop + 1)))
                  ^
  252.           goto err;
  253.       res->neg = (num->neg ^ divisor->neg);

crypto/bn/bn_lib.c:940:1: Parameter `*a->d`
    938.   }
    939.   
    940. > BIGNUM *bn_wexpand(BIGNUM *a, int words)
    941.   {
    942.       return (words <= a->dmax) ? a : bn_expand2(a, words);

crypto/bn/bn_div.c:403:9: Call
  401.            */
  402.           int neg = num->neg;
  403.           BN_rshift(rm, snum, norm_shift);
                 ^
  404.           if (!BN_is_zero(rm))
  405.               rm->neg = neg;

crypto/bn/bn_shift.c:122:1: <Length trace>
120.   }
121.   
122. > int BN_rshift(BIGNUM *r, const BIGNUM *a, int n)
123.   {
124.       int i, j, nw, lb, rb;

crypto/bn/bn_shift.c:122:1: Parameter `*a->d`
    120.   }
    121.   
    122. > int BN_rshift(BIGNUM *r, const BIGNUM *a, int n)
    123.   {
    124.       int i, j, nw, lb, rb;

crypto/bn/bn_shift.c:153:5: Assignment
    151.       }
    152.   
    153.       f = &(a->d[nw]);
               ^
    154.       t = r->d;
    155.       j = a->top - nw;

crypto/bn/bn_shift.c:162:15: Assignment
    160.               *(t++) = *(f++);
    161.       } else {
    162.           l = *(f++);
                         ^
    163.           for (i = j - 1; i != 0; i--) {
    164.               tmp = (l >> rb) & BN_MASK2;

crypto/bn/bn_shift.c:165:17: Array access: Offset: [1, +oo] Size: [0, 8388607] by call to `BN_div` 
    163.           for (i = j - 1; i != 0; i--) {
    164.               tmp = (l >> rb) & BN_MASK2;
    165.               l = *(f++);
                           ^
    166.               *(t++) = (tmp | (l << lb)) & BN_MASK2;
    167.           }

int BN_rshift(BIGNUM *r, const BIGNUM *a, int n)
{
    int i, j, nw, lb, rb;
    BN_ULONG *t, *f;
    BN_ULONG l, tmp;
    bn_check_top(r);
    bn_check_top(a);
    if (n < 0) {
        BNerr(BN_F_BN_RSHIFT, BN_R_INVALID_SHIFT);
        return 0;
    }
    nw = n / BN_BITS2;
    rb = n % BN_BITS2;
    lb = BN_BITS2 - rb;
    if (nw >= a->top || a->top == 0) {
        BN_zero(r);
        return 1;
    }
    i = (BN_num_bits(a) - n + (BN_BITS2 - 1)) / BN_BITS2;
    if (r != a) {
        if (bn_wexpand(r, i) == NULL)
            return 0;
        r->neg = a->neg;
    } else {
        if (n == 0)
            return 1;
    }
    f = &(a->d[nw]);
    t = r->d;
    j = a->top - nw;
    r->top = i;
    if (rb == 0) {
        for (i = j; i != 0; i--)
            *(t++) = *(f++);
    } else {
        l = *(f++);
        for (i = j - 1; i != 0; i--) {
            tmp = (l >> rb) & BN_MASK2;
            l = *(f++);
            *(t++) = (tmp | (l << lb)) & BN_MASK2;
        }
        if ((l = (l >> rb) & BN_MASK2))
            *(t) = l;
    }
    if (!r->top)
        r->neg = 0;
    bn_check_top(r);
    return 1;
}
['static int test_negzero(void)\n{\n    BIGNUM *a = NULL, *b = NULL, *c = NULL, *d = NULL;\n    BIGNUM *numerator = NULL, *denominator = NULL;\n    int consttime, st = 0;\n    if (!TEST_ptr(a = BN_new())\n            || !TEST_ptr(b = BN_new())\n            || !TEST_ptr(c = BN_new())\n            || !TEST_ptr(d = BN_new()))\n        goto err;\n    if (!TEST_true(BN_set_word(a, 1)))\n        goto err;\n    BN_set_negative(a, 1);\n    BN_zero(b);\n    if (!TEST_true(BN_mul(c, a, b, ctx)))\n        goto err;\n    if (!TEST_BN_eq_zero(c)\n            || !TEST_BN_ge_zero(c))\n        goto err;\n    for (consttime = 0; consttime < 2; consttime++) {\n        if (!TEST_ptr(numerator = BN_new())\n                || !TEST_ptr(denominator = BN_new()))\n            goto err;\n        if (consttime) {\n            BN_set_flags(numerator, BN_FLG_CONSTTIME);\n            BN_set_flags(denominator, BN_FLG_CONSTTIME);\n        }\n        if (!TEST_true(BN_set_word(numerator, 1))\n                || !TEST_true(BN_set_word(denominator, 2)))\n            goto err;\n        BN_set_negative(numerator, 1);\n        if (!TEST_true(BN_div(a, b, numerator, denominator, ctx))\n                || !TEST_BN_eq_zero(a)\n                || !TEST_BN_ge_zero(a))\n            goto err;\n        if (!TEST_true(BN_set_word(denominator, 1))\n                || !TEST_true(BN_div(a, b, numerator, denominator, ctx))\n                || !TEST_BN_eq_zero(b)\n                || !TEST_BN_ge_zero(b))\n            goto err;\n        BN_free(numerator);\n        BN_free(denominator);\n        numerator = denominator = NULL;\n    }\n    BN_zero(a);\n    BN_set_negative(a, 1);\n    if (BN_is_negative(a))\n        goto err;\n    st = 1;\nerr:\n    BN_free(a);\n    BN_free(b);\n    BN_free(c);\n    BN_free(d);\n    BN_free(numerator);\n    BN_free(denominator);\n    return st;\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}', 'static ossl_inline BIGNUM *bn_expand(BIGNUM *a, int bits)\n{\n    if (bits > (INT_MAX - BN_BITS2 + 1))\n        return NULL;\n    if (((bits+BN_BITS2-1)/BN_BITS2) <= (a)->dmax)\n        return a;\n    return bn_expand2((a),(bits+BN_BITS2-1)/BN_BITS2);\n}', 'int BN_div(BIGNUM *dv, BIGNUM *rm, const BIGNUM *num, const BIGNUM *divisor,\n           BN_CTX *ctx)\n{\n    int norm_shift, i, loop;\n    BIGNUM *tmp, wnum, *snum, *sdiv, *res;\n    BN_ULONG *resp, *wnump;\n    BN_ULONG d0, d1;\n    int num_n, div_n;\n    int no_branch = 0;\n    if ((num->top > 0 && num->d[num->top - 1] == 0) ||\n        (divisor->top > 0 && divisor->d[divisor->top - 1] == 0)) {\n        BNerr(BN_F_BN_DIV, BN_R_NOT_INITIALIZED);\n        return 0;\n    }\n    bn_check_top(num);\n    bn_check_top(divisor);\n    if ((BN_get_flags(num, BN_FLG_CONSTTIME) != 0)\n        || (BN_get_flags(divisor, BN_FLG_CONSTTIME) != 0)) {\n        no_branch = 1;\n    }\n    bn_check_top(dv);\n    bn_check_top(rm);\n    if (BN_is_zero(divisor)) {\n        BNerr(BN_F_BN_DIV, BN_R_DIV_BY_ZERO);\n        return 0;\n    }\n    if (!no_branch && BN_ucmp(num, divisor) < 0) {\n        if (rm != NULL) {\n            if (BN_copy(rm, num) == NULL)\n                return 0;\n        }\n        if (dv != NULL)\n            BN_zero(dv);\n        return 1;\n    }\n    BN_CTX_start(ctx);\n    res = (dv == NULL) ? BN_CTX_get(ctx) : dv;\n    tmp = BN_CTX_get(ctx);\n    snum = BN_CTX_get(ctx);\n    sdiv = BN_CTX_get(ctx);\n    if (sdiv == NULL)\n        goto err;\n    norm_shift = BN_BITS2 - ((BN_num_bits(divisor)) % BN_BITS2);\n    if (!(BN_lshift(sdiv, divisor, norm_shift)))\n        goto err;\n    sdiv->neg = 0;\n    norm_shift += BN_BITS2;\n    if (!(BN_lshift(snum, num, norm_shift)))\n        goto err;\n    snum->neg = 0;\n    if (no_branch) {\n        if (snum->top <= sdiv->top + 1) {\n            if (bn_wexpand(snum, sdiv->top + 2) == NULL)\n                goto err;\n            for (i = snum->top; i < sdiv->top + 2; i++)\n                snum->d[i] = 0;\n            snum->top = sdiv->top + 2;\n        } else {\n            if (bn_wexpand(snum, snum->top + 1) == NULL)\n                goto err;\n            snum->d[snum->top] = 0;\n            snum->top++;\n        }\n    }\n    div_n = sdiv->top;\n    num_n = snum->top;\n    loop = num_n - div_n;\n    wnum.neg = 0;\n    wnum.d = &(snum->d[loop]);\n    wnum.top = div_n;\n    wnum.dmax = snum->dmax - loop;\n    d0 = sdiv->d[div_n - 1];\n    d1 = (div_n == 1) ? 0 : sdiv->d[div_n - 2];\n    wnump = &(snum->d[num_n - 1]);\n    if (!bn_wexpand(res, (loop + 1)))\n        goto err;\n    res->neg = (num->neg ^ divisor->neg);\n    res->top = loop - no_branch;\n    resp = &(res->d[loop - 1]);\n    if (!bn_wexpand(tmp, (div_n + 1)))\n        goto err;\n    if (!no_branch) {\n        if (BN_ucmp(&wnum, sdiv) >= 0) {\n            bn_clear_top2max(&wnum);\n            bn_sub_words(wnum.d, wnum.d, sdiv->d, div_n);\n            *resp = 1;\n        } else\n            res->top--;\n    }\n    resp++;\n    if (res->top == 0)\n        res->neg = 0;\n    else\n        resp--;\n    for (i = 0; i < loop - 1; i++, wnump--) {\n        BN_ULONG q, l0;\n# if defined(BN_DIV3W) && !defined(OPENSSL_NO_ASM)\n        BN_ULONG bn_div_3_words(BN_ULONG *, BN_ULONG, BN_ULONG);\n        q = bn_div_3_words(wnump, d1, d0);\n# else\n        BN_ULONG n0, n1, rem = 0;\n        n0 = wnump[0];\n        n1 = wnump[-1];\n        if (n0 == d0)\n            q = BN_MASK2;\n        else {\n#  ifdef BN_LLONG\n            BN_ULLONG t2;\n#   if defined(BN_LLONG) && defined(BN_DIV2W) && !defined(bn_div_words)\n            q = (BN_ULONG)(((((BN_ULLONG) n0) << BN_BITS2) | n1) / d0);\n#   else\n            q = bn_div_words(n0, n1, d0);\n#   endif\n#   ifndef REMAINDER_IS_ALREADY_CALCULATED\n            rem = (n1 - q * d0) & BN_MASK2;\n#   endif\n            t2 = (BN_ULLONG) d1 *q;\n            for (;;) {\n                if (t2 <= ((((BN_ULLONG) rem) << BN_BITS2) | wnump[-2]))\n                    break;\n                q--;\n                rem += d0;\n                if (rem < d0)\n                    break;\n                t2 -= d1;\n            }\n#  else\n            BN_ULONG t2l, t2h;\n            q = bn_div_words(n0, n1, d0);\n#   ifndef REMAINDER_IS_ALREADY_CALCULATED\n            rem = (n1 - q * d0) & BN_MASK2;\n#   endif\n#   if defined(BN_UMULT_LOHI)\n            BN_UMULT_LOHI(t2l, t2h, d1, q);\n#   elif defined(BN_UMULT_HIGH)\n            t2l = d1 * q;\n            t2h = BN_UMULT_HIGH(d1, q);\n#   else\n            {\n                BN_ULONG ql, qh;\n                t2l = LBITS(d1);\n                t2h = HBITS(d1);\n                ql = LBITS(q);\n                qh = HBITS(q);\n                mul64(t2l, t2h, ql, qh);\n            }\n#   endif\n            for (;;) {\n                if ((t2h < rem) || ((t2h == rem) && (t2l <= wnump[-2])))\n                    break;\n                q--;\n                rem += d0;\n                if (rem < d0)\n                    break;\n                if (t2l < d1)\n                    t2h--;\n                t2l -= d1;\n            }\n#  endif\n        }\n# endif\n        l0 = bn_mul_words(tmp->d, sdiv->d, div_n, q);\n        tmp->d[div_n] = l0;\n        wnum.d--;\n        if (bn_sub_words(wnum.d, wnum.d, tmp->d, div_n + 1)) {\n            q--;\n            if (bn_add_words(wnum.d, wnum.d, sdiv->d, div_n))\n                (*wnump)++;\n        }\n        resp--;\n        *resp = q;\n    }\n    bn_correct_top(snum);\n    if (rm != NULL) {\n        int neg = num->neg;\n        BN_rshift(rm, snum, norm_shift);\n        if (!BN_is_zero(rm))\n            rm->neg = neg;\n        bn_check_top(rm);\n    }\n    if (no_branch)\n        bn_correct_top(res);\n    BN_CTX_end(ctx);\n    return 1;\n err:\n    bn_check_top(rm);\n    BN_CTX_end(ctx);\n    return 0;\n}', 'BIGNUM *bn_wexpand(BIGNUM *a, int words)\n{\n    return (words <= a->dmax) ? a : bn_expand2(a, words);\n}', 'int BN_rshift(BIGNUM *r, const BIGNUM *a, int n)\n{\n    int i, j, nw, lb, rb;\n    BN_ULONG *t, *f;\n    BN_ULONG l, tmp;\n    bn_check_top(r);\n    bn_check_top(a);\n    if (n < 0) {\n        BNerr(BN_F_BN_RSHIFT, BN_R_INVALID_SHIFT);\n        return 0;\n    }\n    nw = n / BN_BITS2;\n    rb = n % BN_BITS2;\n    lb = BN_BITS2 - rb;\n    if (nw >= a->top || a->top == 0) {\n        BN_zero(r);\n        return 1;\n    }\n    i = (BN_num_bits(a) - n + (BN_BITS2 - 1)) / BN_BITS2;\n    if (r != a) {\n        if (bn_wexpand(r, i) == NULL)\n            return 0;\n        r->neg = a->neg;\n    } else {\n        if (n == 0)\n            return 1;\n    }\n    f = &(a->d[nw]);\n    t = r->d;\n    j = a->top - nw;\n    r->top = i;\n    if (rb == 0) {\n        for (i = j; i != 0; i--)\n            *(t++) = *(f++);\n    } else {\n        l = *(f++);\n        for (i = j - 1; i != 0; i--) {\n            tmp = (l >> rb) & BN_MASK2;\n            l = *(f++);\n            *(t++) = (tmp | (l << lb)) & BN_MASK2;\n        }\n        if ((l = (l >> rb) & BN_MASK2))\n            *(t) = l;\n    }\n    if (!r->top)\n        r->neg = 0;\n    bn_check_top(r);\n    return 1;\n}']