test/bntest.c:1885: error: BUFFER_OVERRUN_L3
  Offset added: [8, +oo] Size: [0, 536870848] by call to `BN_mod_exp`.
Showing all 19 steps of the trace


test/bntest.c:1883:5: Call
1881.               || !TEST_ptr(r = BN_new()))
1882.           goto err;
1883.       BN_zero(zero);
            ^
1884.   
1885.       if (!TEST_true(BN_mod_exp(r, a, zero, BN_value_one(), NULL))

crypto/bn/bn_lib.c:402:15: Assignment
  400.       a->neg = 0;
  401.       a->d[0] = w;
  402.       a->top = (w ? 1 : 0);
                       ^
  403.       bn_check_top(a);
  404.       return (1);

crypto/bn/bn_lib.c:402:5: Assignment
  400.       a->neg = 0;
  401.       a->d[0] = w;
  402.       a->top = (w ? 1 : 0);
             ^
  403.       bn_check_top(a);
  404.       return (1);

test/bntest.c:1885:10: Call
1883.       BN_zero(zero);
1884.   
1885.       if (!TEST_true(BN_mod_exp(r, a, zero, BN_value_one(), NULL))
                 ^
1886.               || !TEST_true(BN_is_zero(r))
1887.               || !TEST_true(BN_mod_exp_mont(r, a, zero, BN_value_one(),

crypto/bn/bn_exp.c:91:1: Parameter `*r->d`
  89.   }
  90.   
  91. > int BN_mod_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, const BIGNUM *m,
  92.                  BN_CTX *ctx)
  93.   {

crypto/bn/bn_exp.c:141:19: Call
  139.               && (BN_get_flags(p, BN_FLG_CONSTTIME) == 0)) {
  140.               BN_ULONG A = a->d[0];
  141.               ret = BN_mod_exp_mont_word(r, A, p, m, ctx, NULL);
                           ^
  142.           } else
  143.   # endif

crypto/bn/bn_exp.c:1091:1: Parameter `*rr->d`
    1089.   }
    1090.   
    1091. > int BN_mod_exp_mont_word(BIGNUM *rr, BN_ULONG a, const BIGNUM *p,
    1092.                            const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *in_mont)
    1093.   {

crypto/bn/bn_exp.c:1138:13: Call
    1136.           if (BN_is_one(m)) {
    1137.               ret = 1;
    1138.               BN_zero(rr);
                        ^
    1139.           } else {
    1140.               ret = BN_one(rr);

crypto/bn/bn_lib.c:395:1: Parameter `*a->d`
      393.   }
      394.   
      395. > int BN_set_word(BIGNUM *a, BN_ULONG w)
      396.   {
      397.       bn_check_top(a);

crypto/bn/bn_lib.c:398:9: Call
      396.   {
      397.       bn_check_top(a);
      398.       if (bn_expand(a, (int)sizeof(BN_ULONG) * 8) == NULL)
                     ^
      399.           return (0);
      400.       a->neg = 0;

crypto/bn/bn_lcl.h:660:1: Parameter `*a->d`
        658.                            const BIGNUM *add, const BIGNUM *rem, BN_CTX *ctx);
        659.   
        660. > static ossl_inline BIGNUM *bn_expand(BIGNUM *a, int bits)
        661.   {
        662.       if (bits > (INT_MAX - BN_BITS2 + 1))

crypto/bn/bn_lcl.h:668:12: Call
        666.           return a;
        667.   
        668.       return bn_expand2((a),(bits+BN_BITS2-1)/BN_BITS2);
                          ^
        669.   }
        670.   

crypto/bn/bn_lib.c:284:1: Parameter `*b->d`
          282.    */
          283.   
          284. > BIGNUM *bn_expand2(BIGNUM *b, int words)
          285.   {
          286.       bn_check_top(b);

crypto/bn/bn_lib.c:289:23: Call
          287.   
          288.       if (words > b->dmax) {
          289.           BN_ULONG *a = bn_expand_internal(b, words);
                                       ^
          290.           if (!a)
          291.               return NULL;

crypto/bn/bn_lib.c:246:1: <Offset trace>
244.   /* This is used by bn_expand2() */
245.   /* The caller MUST check that words > b->dmax before calling this */
246. > static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words)
247.   {
248.       BN_ULONG *a = NULL;

crypto/bn/bn_lib.c:246:1: Parameter `b->top`
            244.   /* This is used by bn_expand2() */
            245.   /* The caller MUST check that words > b->dmax before calling this */
            246. > static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words)
            247.   {
            248.       BN_ULONG *a = NULL;

crypto/bn/bn_lib.c:246:1: <Length trace>
244.   /* This is used by bn_expand2() */
245.   /* The caller MUST check that words > b->dmax before calling this */
246. > static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words)
247.   {
248.       BN_ULONG *a = NULL;

crypto/bn/bn_lib.c:246:1: Parameter `*b->d`
            244.   /* This is used by bn_expand2() */
            245.   /* The caller MUST check that words > b->dmax before calling this */
            246. > static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words)
            247.   {
            248.       BN_ULONG *a = NULL;

crypto/bn/bn_lib.c:271:9: Array access: Offset added: [8, +oo] Size: [0, 536870848] by call to `BN_mod_exp` 
            269.       assert(b->top <= words);
            270.       if (b->top > 0)
            271.           memcpy(a, b->d, sizeof(*a) * b->top);
                           ^
            272.   
            273.       return a;

static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words)
{
    BN_ULONG *a = NULL;
    bn_check_top(b);
    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_expmodzero()\n{\n    BIGNUM *a = NULL, *r = NULL, *zero = NULL;\n    int st = 0;\n    if (!TEST_ptr(zero = BN_new())\n            || !TEST_ptr(a = BN_new())\n            || !TEST_ptr(r = BN_new()))\n        goto err;\n    BN_zero(zero);\n    if (!TEST_true(BN_mod_exp(r, a, zero, BN_value_one(), NULL))\n            || !TEST_true(BN_is_zero(r))\n            || !TEST_true(BN_mod_exp_mont(r, a, zero, BN_value_one(),\n                                          NULL, NULL))\n            || !TEST_true(BN_is_zero(r))\n            || !TEST_true(BN_mod_exp_mont_consttime(r, a, zero,\n                                                    BN_value_one(),\n                                                    NULL, NULL))\n            || !TEST_true(BN_is_zero(r))\n            || !TEST_true(BN_mod_exp_mont_word(r, 42, zero,\n                                               BN_value_one(), NULL, NULL))\n            || !TEST_true(BN_is_zero(r)))\n        goto err;\n    st = 1;\nerr:\n    BN_free(zero);\n    BN_free(a);\n    BN_free(r);\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}', 'int BN_mod_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, const BIGNUM *m,\n               BN_CTX *ctx)\n{\n    int ret;\n    bn_check_top(a);\n    bn_check_top(p);\n    bn_check_top(m);\n#define MONT_MUL_MOD\n#define MONT_EXP_WORD\n#define RECP_MUL_MOD\n#ifdef MONT_MUL_MOD\n    if (BN_is_odd(m)) {\n# ifdef MONT_EXP_WORD\n        if (a->top == 1 && !a->neg\n            && (BN_get_flags(p, BN_FLG_CONSTTIME) == 0)) {\n            BN_ULONG A = a->d[0];\n            ret = BN_mod_exp_mont_word(r, A, p, m, ctx, NULL);\n        } else\n# endif\n            ret = BN_mod_exp_mont(r, a, p, m, ctx, NULL);\n    } else\n#endif\n#ifdef RECP_MUL_MOD\n    {\n        ret = BN_mod_exp_recp(r, a, p, m, ctx);\n    }\n#else\n    {\n        ret = BN_mod_exp_simple(r, a, p, m, ctx);\n    }\n#endif\n    bn_check_top(r);\n    return (ret);\n}', 'int BN_mod_exp_mont_word(BIGNUM *rr, BN_ULONG a, const BIGNUM *p,\n                         const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *in_mont)\n{\n    BN_MONT_CTX *mont = NULL;\n    int b, bits, ret = 0;\n    int r_is_one;\n    BN_ULONG w, next_w;\n    BIGNUM *d, *r, *t;\n    BIGNUM *swap_tmp;\n#define BN_MOD_MUL_WORD(r, w, m) \\\n                (BN_mul_word(r, (w)) && \\\n                (   \\\n                        (BN_mod(t, r, m, ctx) && (swap_tmp = r, r = t, t = swap_tmp, 1))))\n#define BN_TO_MONTGOMERY_WORD(r, w, mont) \\\n                (BN_set_word(r, (w)) && BN_to_montgomery(r, r, (mont), ctx))\n    if (BN_get_flags(p, BN_FLG_CONSTTIME) != 0) {\n        BNerr(BN_F_BN_MOD_EXP_MONT_WORD, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);\n        return 0;\n    }\n    bn_check_top(p);\n    bn_check_top(m);\n    if (!BN_is_odd(m)) {\n        BNerr(BN_F_BN_MOD_EXP_MONT_WORD, BN_R_CALLED_WITH_EVEN_MODULUS);\n        return (0);\n    }\n    if (m->top == 1)\n        a %= m->d[0];\n    bits = BN_num_bits(p);\n    if (bits == 0) {\n        if (BN_is_one(m)) {\n            ret = 1;\n            BN_zero(rr);\n        } else {\n            ret = BN_one(rr);\n        }\n        return ret;\n    }\n    if (a == 0) {\n        BN_zero(rr);\n        ret = 1;\n        return ret;\n    }\n    BN_CTX_start(ctx);\n    d = BN_CTX_get(ctx);\n    r = BN_CTX_get(ctx);\n    t = BN_CTX_get(ctx);\n    if (d == NULL || r == NULL || t == NULL)\n        goto err;\n    if (in_mont != NULL)\n        mont = in_mont;\n    else {\n        if ((mont = BN_MONT_CTX_new()) == NULL)\n            goto err;\n        if (!BN_MONT_CTX_set(mont, m, ctx))\n            goto err;\n    }\n    r_is_one = 1;\n    w = a;\n    for (b = bits - 2; b >= 0; b--) {\n        next_w = w * w;\n        if ((next_w / w) != w) {\n            if (r_is_one) {\n                if (!BN_TO_MONTGOMERY_WORD(r, w, mont))\n                    goto err;\n                r_is_one = 0;\n            } else {\n                if (!BN_MOD_MUL_WORD(r, w, m))\n                    goto err;\n            }\n            next_w = 1;\n        }\n        w = next_w;\n        if (!r_is_one) {\n            if (!BN_mod_mul_montgomery(r, r, r, mont, ctx))\n                goto err;\n        }\n        if (BN_is_bit_set(p, b)) {\n            next_w = w * a;\n            if ((next_w / a) != w) {\n                if (r_is_one) {\n                    if (!BN_TO_MONTGOMERY_WORD(r, w, mont))\n                        goto err;\n                    r_is_one = 0;\n                } else {\n                    if (!BN_MOD_MUL_WORD(r, w, m))\n                        goto err;\n                }\n                next_w = a;\n            }\n            w = next_w;\n        }\n    }\n    if (w != 1) {\n        if (r_is_one) {\n            if (!BN_TO_MONTGOMERY_WORD(r, w, mont))\n                goto err;\n            r_is_one = 0;\n        } else {\n            if (!BN_MOD_MUL_WORD(r, w, m))\n                goto err;\n        }\n    }\n    if (r_is_one) {\n        if (!BN_one(rr))\n            goto err;\n    } else {\n        if (!BN_from_montgomery(rr, r, mont, ctx))\n            goto err;\n    }\n    ret = 1;\n err:\n    if (in_mont == NULL)\n        BN_MONT_CTX_free(mont);\n    BN_CTX_end(ctx);\n    bn_check_top(rr);\n    return (ret);\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}', 'BIGNUM *bn_expand2(BIGNUM *b, int words)\n{\n    bn_check_top(b);\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    bn_check_top(b);\n    return b;\n}', 'static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words)\n{\n    BN_ULONG *a = NULL;\n    bn_check_top(b);\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}']