test/exptest.c:159: error: BUFFER_OVERRUN_L3
  Offset added: [8, +oo] Size: [0, +oo] by call to `BN_div`.
Showing all 22 steps of the trace


test/exptest.c:149:5: Call
147.       RAND_bytes(&c, 1);
148.       c = (c % BN_BITS) - BN_BITS2;
149.       BN_rand(a, NUM_BITS + c, BN_RAND_TOP_ONE, BN_RAND_BOTTOM_ANY);
           ^
150.   
151.       RAND_bytes(&c, 1);

crypto/bn/bn_rand.c:114:1: Parameter `*rnd->d`
  112.   }
  113.   
  114. > int BN_rand(BIGNUM *rnd, int bits, int top, int bottom)
  115.   {
  116.       return bnrand(NORMAL, rnd, bits, top, bottom);

crypto/bn/bn_rand.c:116:12: Call
  114.   int BN_rand(BIGNUM *rnd, int bits, int top, int bottom)
  115.   {
  116.       return bnrand(NORMAL, rnd, bits, top, bottom);
                    ^
  117.   }
  118.   

crypto/bn/bn_rand.c:23:1: Parameter `*rnd->d`
    21.   } BNRAND_FLAG;
    22.   
    23. > static int bnrand(BNRAND_FLAG flag, BIGNUM *rnd, int bits, int top, int bottom)
    24.   {
    25.       unsigned char *buf = NULL;

test/exptest.c:157:5: Call
155.       RAND_bytes(&c, 1);
156.       c = (c % BN_BITS) - BN_BITS2;
157.       BN_rand(m, NUM_BITS + c, BN_RAND_TOP_ONE, BN_RAND_BOTTOM_ODD);
           ^
158.   
159.       if (!TEST_true(BN_mod(a, a, m, ctx))

crypto/bn/bn_rand.c:114:1: Parameter `*rnd->d`
  112.   }
  113.   
  114. > int BN_rand(BIGNUM *rnd, int bits, int top, int bottom)
  115.   {
  116.       return bnrand(NORMAL, rnd, bits, top, bottom);

crypto/bn/bn_rand.c:116:12: Call
  114.   int BN_rand(BIGNUM *rnd, int bits, int top, int bottom)
  115.   {
  116.       return bnrand(NORMAL, rnd, bits, top, bottom);
                    ^
  117.   }
  118.   

crypto/bn/bn_rand.c:23:1: Parameter `*rnd->d`
    21.   } BNRAND_FLAG;
    22.   
    23. > static int bnrand(BNRAND_FLAG flag, BIGNUM *rnd, int bits, int top, int bottom)
    24.   {
    25.       unsigned char *buf = NULL;

test/exptest.c:159:10: Call
157.       BN_rand(m, NUM_BITS + c, BN_RAND_TOP_ONE, BN_RAND_BOTTOM_ODD);
158.   
159.       if (!TEST_true(BN_mod(a, a, m, ctx))
                ^
160.           || !TEST_true(BN_mod(b, b, m, ctx))
161.           || !TEST_true(BN_mod_exp_mont(r_mont, a, b, m, ctx, NULL))

crypto/bn/bn_div.c:209:1: Parameter `*dv->d`
  207.    * If 'dv' or 'rm' is NULL, the respective value is not returned.
  208.    */
  209. > int BN_div(BIGNUM *dv, BIGNUM *rm, const BIGNUM *num, const BIGNUM *divisor,
  210.              BN_CTX *ctx)
  211.   {

crypto/bn/bn_div.c:229:11: Call
  227.       }
  228.   
  229.       ret = bn_div_fixed_top(dv, rm, num, divisor, ctx);
                   ^
  230.   
  231.       if (ret) {

crypto/bn/bn_div.c:264:1: Parameter `*dv->d`
    262.    *       divisor's length is considered public;
    263.    */
    264. > int bn_div_fixed_top(BIGNUM *dv, BIGNUM *rm, const BIGNUM *num,
    265.                        const BIGNUM *divisor, BN_CTX *ctx)
    266.   {

crypto/bn/bn_div.c:327:10: Call
    325.   
    326.       /* Setup quotient */
    327.       if (!bn_wexpand(res, loop))
                    ^
    328.           goto err;
    329.       res->neg = (num->neg ^ divisor->neg);

crypto/bn/bn_lib.c:962:1: Parameter `*a->d`
      960.   }
      961.   
      962. > BIGNUM *bn_wexpand(BIGNUM *a, int words)
      963.   {
      964.       return (words <= a->dmax) ? a : bn_expand2(a, words);

crypto/bn/bn_lib.c:964:37: Call
      962.   BIGNUM *bn_wexpand(BIGNUM *a, int words)
      963.   {
      964.       return (words <= a->dmax) ? a : bn_expand2(a, words);
                                                 ^
      965.   }
      966.   

crypto/bn/bn_lib.c:245:1: Parameter `*b->d`
        243.    */
        244.   
        245. > BIGNUM *bn_expand2(BIGNUM *b, int words)
        246.   {
        247.       if (words > b->dmax) {

crypto/bn/bn_lib.c:248:23: Call
        246.   {
        247.       if (words > b->dmax) {
        248.           BN_ULONG *a = bn_expand_internal(b, words);
                                     ^
        249.           if (!a)
        250.               return NULL;

crypto/bn/bn_lib.c:209:1: <Offset trace>
207.   /* This is used by bn_expand2() */
208.   /* The caller MUST check that words > b->dmax before calling this */
209. > static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words)
210.   {
211.       BN_ULONG *a = NULL;

crypto/bn/bn_lib.c:209:1: Parameter `b->top`
          207.   /* This is used by bn_expand2() */
          208.   /* The caller MUST check that words > b->dmax before calling this */
          209. > static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words)
          210.   {
          211.       BN_ULONG *a = NULL;

crypto/bn/bn_lib.c:209:1: <Length trace>
207.   /* This is used by bn_expand2() */
208.   /* The caller MUST check that words > b->dmax before calling this */
209. > static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words)
210.   {
211.       BN_ULONG *a = NULL;

crypto/bn/bn_lib.c:209:1: Parameter `*b->d`
          207.   /* This is used by bn_expand2() */
          208.   /* The caller MUST check that words > b->dmax before calling this */
          209. > static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words)
          210.   {
          211.       BN_ULONG *a = NULL;

crypto/bn/bn_lib.c:232:9: Array access: Offset added: [8, +oo] Size: [0, +oo] by call to `BN_div` 
          230.       assert(b->top <= words);
          231.       if (b->top > 0)
          232.           memcpy(a, b->d, sizeof(*a) * b->top);
                         ^
          233.   
          234.       return a;

static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words)
{
    BN_ULONG *a = NULL;
    if (words > (INT_MAX / (4 * BN_BITS2))) {
        BNerr(BN_F_BN_EXPAND_INTERNAL, BN_R_BIGNUM_TOO_LONG);
        return NULL;
    }
    if (BN_get_flags(b, BN_FLG_STATIC_DATA)) {
        BNerr(BN_F_BN_EXPAND_INTERNAL, BN_R_EXPAND_ON_STATIC_BIGNUM_DATA);
        return NULL;
    }
    if (BN_get_flags(b, BN_FLG_SECURE))
        a = OPENSSL_secure_zalloc(words * sizeof(*a));
    else
        a = OPENSSL_zalloc(words * sizeof(*a));
    if (a == NULL) {
        BNerr(BN_F_BN_EXPAND_INTERNAL, ERR_R_MALLOC_FAILURE);
        return NULL;
    }
    assert(b->top <= words);
    if (b->top > 0)
        memcpy(a, b->d, sizeof(*a) * b->top);
    return a;
}
['static int test_mod_exp(int round)\n{\n    BN_CTX *ctx;\n    unsigned char c;\n    int ret = 0;\n    BIGNUM *r_mont = NULL;\n    BIGNUM *r_mont_const = NULL;\n    BIGNUM *r_recp = NULL;\n    BIGNUM *r_simple = NULL;\n    BIGNUM *a = NULL;\n    BIGNUM *b = NULL;\n    BIGNUM *m = NULL;\n    if (!TEST_ptr(ctx = BN_CTX_new()))\n        goto err;\n    if (!TEST_ptr(r_mont = BN_new())\n        || !TEST_ptr(r_mont_const = BN_new())\n        || !TEST_ptr(r_recp = BN_new())\n        || !TEST_ptr(r_simple = BN_new())\n        || !TEST_ptr(a = BN_new())\n        || !TEST_ptr(b = BN_new())\n        || !TEST_ptr(m = BN_new()))\n        goto err;\n    RAND_bytes(&c, 1);\n    c = (c % BN_BITS) - BN_BITS2;\n    BN_rand(a, NUM_BITS + c, BN_RAND_TOP_ONE, BN_RAND_BOTTOM_ANY);\n    RAND_bytes(&c, 1);\n    c = (c % BN_BITS) - BN_BITS2;\n    BN_rand(b, NUM_BITS + c, BN_RAND_TOP_ONE, BN_RAND_BOTTOM_ANY);\n    RAND_bytes(&c, 1);\n    c = (c % BN_BITS) - BN_BITS2;\n    BN_rand(m, NUM_BITS + c, BN_RAND_TOP_ONE, BN_RAND_BOTTOM_ODD);\n    if (!TEST_true(BN_mod(a, a, m, ctx))\n        || !TEST_true(BN_mod(b, b, m, ctx))\n        || !TEST_true(BN_mod_exp_mont(r_mont, a, b, m, ctx, NULL))\n        || !TEST_true(BN_mod_exp_recp(r_recp, a, b, m, ctx))\n        || !TEST_true(BN_mod_exp_simple(r_simple, a, b, m, ctx))\n        || !TEST_true(BN_mod_exp_mont_consttime(r_mont_const, a, b, m, ctx, NULL)))\n        goto err;\n    if (!TEST_BN_eq(r_simple, r_mont)\n        || !TEST_BN_eq(r_simple, r_recp)\n        || !TEST_BN_eq(r_simple, r_mont_const)) {\n        if (BN_cmp(r_simple, r_mont) != 0)\n            TEST_info("simple and mont results differ");\n        if (BN_cmp(r_simple, r_mont_const) != 0)\n            TEST_info("simple and mont const time results differ");\n        if (BN_cmp(r_simple, r_recp) != 0)\n            TEST_info("simple and recp results differ");\n        BN_print_var(a);\n        BN_print_var(b);\n        BN_print_var(m);\n        BN_print_var(r_simple);\n        BN_print_var(r_recp);\n        BN_print_var(r_mont);\n        BN_print_var(r_mont_const);\n        goto err;\n    }\n    ret = 1;\n err:\n    BN_free(r_mont);\n    BN_free(r_mont_const);\n    BN_free(r_recp);\n    BN_free(r_simple);\n    BN_free(a);\n    BN_free(b);\n    BN_free(m);\n    BN_CTX_free(ctx);\n    return ret;\n}', 'int BN_rand(BIGNUM *rnd, int bits, int top, int bottom)\n{\n    return bnrand(NORMAL, rnd, bits, top, bottom);\n}', 'static int bnrand(BNRAND_FLAG flag, BIGNUM *rnd, int bits, int top, int bottom)\n{\n    unsigned char *buf = NULL;\n    int b, ret = 0, bit, bytes, mask;\n    if (bits == 0) {\n        if (top != BN_RAND_TOP_ANY || bottom != BN_RAND_BOTTOM_ANY)\n            goto toosmall;\n        BN_zero(rnd);\n        return 1;\n    }\n    if (bits < 0 || (bits == 1 && top > 0))\n        goto toosmall;\n    bytes = (bits + 7) / 8;\n    bit = (bits - 1) % 8;\n    mask = 0xff << (bit + 1);\n    buf = OPENSSL_malloc(bytes);\n    if (buf == NULL) {\n        BNerr(BN_F_BNRAND, ERR_R_MALLOC_FAILURE);\n        goto err;\n    }\n#if defined(FIPS_MODE)\n    BNerr(BN_F_BNRAND, ERR_R_INTERNAL_ERROR);\n    goto err;\n#else\n    b = flag == NORMAL ? RAND_bytes(buf, bytes) : RAND_priv_bytes(buf, bytes);\n#endif\n    if (b <= 0)\n        goto err;\n    if (flag == TESTING) {\n        int i;\n        unsigned char c;\n        for (i = 0; i < bytes; i++) {\n#if !defined(FIPS_MODE)\n            if (RAND_bytes(&c, 1) <= 0)\n                goto err;\n#endif\n            if (c >= 128 && i > 0)\n                buf[i] = buf[i - 1];\n            else if (c < 42)\n                buf[i] = 0;\n            else if (c < 84)\n                buf[i] = 255;\n        }\n    }\n    if (top >= 0) {\n        if (top) {\n            if (bit == 0) {\n                buf[0] = 1;\n                buf[1] |= 0x80;\n            } else {\n                buf[0] |= (3 << (bit - 1));\n            }\n        } else {\n            buf[0] |= (1 << bit);\n        }\n    }\n    buf[0] &= ~mask;\n    if (bottom)\n        buf[bytes - 1] |= 1;\n    if (!BN_bin2bn(buf, bytes, rnd))\n        goto err;\n    ret = 1;\n err:\n    OPENSSL_clear_free(buf, bytes);\n    bn_check_top(rnd);\n    return ret;\ntoosmall:\n    BNerr(BN_F_BNRAND, BN_R_BITS_TOO_SMALL);\n    return 0;\n}', 'int BN_div(BIGNUM *dv, BIGNUM *rm, const BIGNUM *num, const BIGNUM *divisor,\n           BN_CTX *ctx)\n{\n    int ret;\n    if (BN_is_zero(divisor)) {\n        BNerr(BN_F_BN_DIV, BN_R_DIV_BY_ZERO);\n        return 0;\n    }\n    if (divisor->d[divisor->top - 1] == 0) {\n        BNerr(BN_F_BN_DIV, BN_R_NOT_INITIALIZED);\n        return 0;\n    }\n    ret = bn_div_fixed_top(dv, rm, num, divisor, ctx);\n    if (ret) {\n        if (dv != NULL)\n            bn_correct_top(dv);\n        if (rm != NULL)\n            bn_correct_top(rm);\n    }\n    return ret;\n}', 'int bn_div_fixed_top(BIGNUM *dv, BIGNUM *rm, const BIGNUM *num,\n                     const BIGNUM *divisor, BN_CTX *ctx)\n{\n    int norm_shift, i, j, loop;\n    BIGNUM *tmp, *snum, *sdiv, *res;\n    BN_ULONG *resp, *wnum, *wnumtop;\n    BN_ULONG d0, d1;\n    int num_n, div_n;\n    assert(divisor->top > 0 && divisor->d[divisor->top - 1] != 0);\n    bn_check_top(num);\n    bn_check_top(divisor);\n    bn_check_top(dv);\n    bn_check_top(rm);\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    if (!BN_copy(sdiv, divisor))\n        goto err;\n    norm_shift = bn_left_align(sdiv);\n    sdiv->neg = 0;\n    if (!(bn_lshift_fixed_top(snum, num, norm_shift)))\n        goto err;\n    div_n = sdiv->top;\n    num_n = snum->top;\n    if (num_n <= div_n) {\n        if (bn_wexpand(snum, div_n + 1) == NULL)\n            goto err;\n        memset(&(snum->d[num_n]), 0, (div_n - num_n + 1) * sizeof(BN_ULONG));\n        snum->top = num_n = div_n + 1;\n    }\n    loop = num_n - div_n;\n    wnum = &(snum->d[loop]);\n    wnumtop = &(snum->d[num_n - 1]);\n    d0 = sdiv->d[div_n - 1];\n    d1 = (div_n == 1) ? 0 : sdiv->d[div_n - 2];\n    if (!bn_wexpand(res, loop))\n        goto err;\n    res->neg = (num->neg ^ divisor->neg);\n    res->top = loop;\n    res->flags |= BN_FLG_FIXED_TOP;\n    resp = &(res->d[loop]);\n    if (!bn_wexpand(tmp, (div_n + 1)))\n        goto err;\n    for (i = 0; i < loop; i++, wnumtop--) {\n        BN_ULONG q, l0;\n# if defined(BN_DIV3W)\n        q = bn_div_3_words(wnumtop, d1, d0);\n# else\n        BN_ULONG n0, n1, rem = 0;\n        n0 = wnumtop[0];\n        n1 = wnumtop[-1];\n        if (n0 == d0)\n            q = BN_MASK2;\n        else {\n            BN_ULONG n2 = (wnumtop == wnum) ? 0 : wnumtop[-2];\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) | n2))\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 <= n2)))\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--;\n        l0 = bn_sub_words(wnum, wnum, tmp->d, div_n + 1);\n        q -= l0;\n        for (l0 = 0 - l0, j = 0; j < div_n; j++)\n            tmp->d[j] = sdiv->d[j] & l0;\n        l0 = bn_add_words(wnum, wnum, tmp->d, div_n);\n        (*wnumtop) += l0;\n        assert((*wnumtop) == 0);\n        *--resp = q;\n    }\n    snum->neg = num->neg;\n    snum->top = div_n;\n    snum->flags |= BN_FLG_FIXED_TOP;\n    if (rm != NULL)\n        bn_rshift_fixed_top(rm, snum, norm_shift);\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}', 'BIGNUM *bn_expand2(BIGNUM *b, int words)\n{\n    if (words > b->dmax) {\n        BN_ULONG *a = bn_expand_internal(b, words);\n        if (!a)\n            return NULL;\n        if (b->d) {\n            OPENSSL_cleanse(b->d, b->dmax * sizeof(b->d[0]));\n            bn_free_d(b);\n        }\n        b->d = a;\n        b->dmax = words;\n    }\n    return b;\n}', 'static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words)\n{\n    BN_ULONG *a = NULL;\n    if (words > (INT_MAX / (4 * BN_BITS2))) {\n        BNerr(BN_F_BN_EXPAND_INTERNAL, BN_R_BIGNUM_TOO_LONG);\n        return NULL;\n    }\n    if (BN_get_flags(b, BN_FLG_STATIC_DATA)) {\n        BNerr(BN_F_BN_EXPAND_INTERNAL, BN_R_EXPAND_ON_STATIC_BIGNUM_DATA);\n        return NULL;\n    }\n    if (BN_get_flags(b, BN_FLG_SECURE))\n        a = OPENSSL_secure_zalloc(words * sizeof(*a));\n    else\n        a = OPENSSL_zalloc(words * sizeof(*a));\n    if (a == NULL) {\n        BNerr(BN_F_BN_EXPAND_INTERNAL, ERR_R_MALLOC_FAILURE);\n        return NULL;\n    }\n    assert(b->top <= words);\n    if (b->top > 0)\n        memcpy(a, b->d, sizeof(*a) * b->top);\n    return a;\n}']