crypto/bn/bn_exp.c:243: error: BUFFER_OVERRUN_L3
  Offset added: [8, +oo] Size: [0, +oo] by call to `BN_mod_mul_reciprocal`.
Showing all 21 steps of the trace


crypto/bn/bn_exp.c:203:13: Call
201.               goto err;
202.           aa->neg = 0;
203.           if (BN_RECP_CTX_set(&recp, aa, ctx) <= 0)
                   ^
204.               goto err;
205.       } else {

crypto/bn/bn_recp.c:45:1: Parameter `*recp->Nr.d`
  43.   }
  44.   
  45. > int BN_RECP_CTX_set(BN_RECP_CTX *recp, const BIGNUM *d, BN_CTX *ctx)
  46.   {
  47.       if (!BN_copy(&(recp->N), d))

crypto/bn/bn_exp.c:243:22: Call
241.           if (BN_is_bit_set(p, wstart) == 0) {
242.               if (!start)
243.                   if (!BN_mod_mul_reciprocal(r, r, r, &recp, ctx))
                            ^
244.                       goto err;
245.               if (wstart == 0)

crypto/bn/bn_recp.c:55:1: Parameter `*recp->Nr.d`
  53.   }
  54.   
  55. > int BN_mod_mul_reciprocal(BIGNUM *r, const BIGNUM *x, const BIGNUM *y,
  56.                             BN_RECP_CTX *recp, BN_CTX *ctx)
  57.   {

crypto/bn/bn_recp.c:77:11: Call
  75.           ca = x;                 /* Just do the mod */
  76.   
  77.       ret = BN_div_recp(NULL, r, ca, recp, ctx);
                  ^
  78.    err:
  79.       BN_CTX_end(ctx);

crypto/bn/bn_recp.c:91:29: Call
    89.   
    90.       BN_CTX_start(ctx);
    91.       d = (dv != NULL) ? dv : BN_CTX_get(ctx);
                                      ^
    92.       r = (rem != NULL) ? rem : BN_CTX_get(ctx);
    93.       a = BN_CTX_get(ctx);

crypto/bn/bn_ctx.c:229:5: Call
      227.       }
      228.       /* OK, make sure the returned bignum is "zero" */
      229.       BN_zero(ret);
                 ^
      230.       /* clear BN_FLG_CONSTTIME if leaked from previous frames */
      231.       ret->flags &= (~BN_FLG_CONSTTIME);

crypto/bn/bn_lib.c:366:15: Assignment
        364.       a->neg = 0;
        365.       a->d[0] = w;
        366.       a->top = (w ? 1 : 0);
                             ^
        367.       a->flags &= ~BN_FLG_FIXED_TOP;
        368.       bn_check_top(a);

crypto/bn/bn_lib.c:366:5: Assignment
        364.       a->neg = 0;
        365.       a->d[0] = w;
        366.       a->top = (w ? 1 : 0);
                   ^
        367.       a->flags &= ~BN_FLG_FIXED_TOP;
        368.       bn_check_top(a);

crypto/bn/bn_recp.c:132:10: Call
    130.        *    = |m/N|
    131.        */
    132.       if (!BN_rshift(a, m, recp->num_bits))
                    ^
    133.           goto err;
    134.       if (!BN_mul(b, a, &(recp->Nr), ctx))

crypto/bn/bn_shift.c:153:1: Parameter `*r->d`
      151.   }
      152.   
      153. > int BN_rshift(BIGNUM *r, const BIGNUM *a, int n)
      154.   {
      155.       int i, j, nw, lb, rb;

crypto/bn/bn_shift.c:176:13: Call
      174.       i = (BN_num_bits(a) - n + (BN_BITS2 - 1)) / BN_BITS2;
      175.       if (r != a) {
      176.           if (bn_wexpand(r, i) == NULL)
                         ^
      177.               return 0;
      178.           r->neg = a->neg;

crypto/bn/bn_lib.c:939:1: Parameter `*a->d`
        937.   }
        938.   
        939. > BIGNUM *bn_wexpand(BIGNUM *a, int words)
        940.   {
        941.       return (words <= a->dmax) ? a : bn_expand2(a, words);

crypto/bn/bn_lib.c:941:37: Call
        939.   BIGNUM *bn_wexpand(BIGNUM *a, int words)
        940.   {
        941.       return (words <= a->dmax) ? a : bn_expand2(a, words);
                                                   ^
        942.   }
        943.   

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_mod_mul_reciprocal` 
            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;
}
['int BN_mod_exp_recp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,\n                    const BIGNUM *m, BN_CTX *ctx)\n{\n    int i, j, bits, ret = 0, wstart, wend, window, wvalue;\n    int start = 1;\n    BIGNUM *aa;\n    BIGNUM *val[TABLE_SIZE];\n    BN_RECP_CTX recp;\n    if (BN_get_flags(p, BN_FLG_CONSTTIME) != 0\n            || BN_get_flags(a, BN_FLG_CONSTTIME) != 0\n            || BN_get_flags(m, BN_FLG_CONSTTIME) != 0) {\n        BNerr(BN_F_BN_MOD_EXP_RECP, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);\n        return 0;\n    }\n    bits = BN_num_bits(p);\n    if (bits == 0) {\n        if (BN_abs_is_word(m, 1)) {\n            ret = 1;\n            BN_zero(r);\n        } else {\n            ret = BN_one(r);\n        }\n        return ret;\n    }\n    BN_CTX_start(ctx);\n    aa = BN_CTX_get(ctx);\n    val[0] = BN_CTX_get(ctx);\n    if (val[0] == NULL)\n        goto err;\n    BN_RECP_CTX_init(&recp);\n    if (m->neg) {\n        if (!BN_copy(aa, m))\n            goto err;\n        aa->neg = 0;\n        if (BN_RECP_CTX_set(&recp, aa, ctx) <= 0)\n            goto err;\n    } else {\n        if (BN_RECP_CTX_set(&recp, m, ctx) <= 0)\n            goto err;\n    }\n    if (!BN_nnmod(val[0], a, m, ctx))\n        goto err;\n    if (BN_is_zero(val[0])) {\n        BN_zero(r);\n        ret = 1;\n        goto err;\n    }\n    window = BN_window_bits_for_exponent_size(bits);\n    if (window > 1) {\n        if (!BN_mod_mul_reciprocal(aa, val[0], val[0], &recp, ctx))\n            goto err;\n        j = 1 << (window - 1);\n        for (i = 1; i < j; i++) {\n            if (((val[i] = BN_CTX_get(ctx)) == NULL) ||\n                !BN_mod_mul_reciprocal(val[i], val[i - 1], aa, &recp, ctx))\n                goto err;\n        }\n    }\n    start = 1;\n    wvalue = 0;\n    wstart = bits - 1;\n    wend = 0;\n    if (!BN_one(r))\n        goto err;\n    for (;;) {\n        if (BN_is_bit_set(p, wstart) == 0) {\n            if (!start)\n                if (!BN_mod_mul_reciprocal(r, r, r, &recp, ctx))\n                    goto err;\n            if (wstart == 0)\n                break;\n            wstart--;\n            continue;\n        }\n        j = wstart;\n        wvalue = 1;\n        wend = 0;\n        for (i = 1; i < window; i++) {\n            if (wstart - i < 0)\n                break;\n            if (BN_is_bit_set(p, wstart - i)) {\n                wvalue <<= (i - wend);\n                wvalue |= 1;\n                wend = i;\n            }\n        }\n        j = wend + 1;\n        if (!start)\n            for (i = 0; i < j; i++) {\n                if (!BN_mod_mul_reciprocal(r, r, r, &recp, ctx))\n                    goto err;\n            }\n        if (!BN_mod_mul_reciprocal(r, r, val[wvalue >> 1], &recp, ctx))\n            goto err;\n        wstart -= wend + 1;\n        wvalue = 0;\n        start = 0;\n        if (wstart < 0)\n            break;\n    }\n    ret = 1;\n err:\n    BN_CTX_end(ctx);\n    BN_RECP_CTX_free(&recp);\n    bn_check_top(r);\n    return ret;\n}', 'int BN_RECP_CTX_set(BN_RECP_CTX *recp, const BIGNUM *d, BN_CTX *ctx)\n{\n    if (!BN_copy(&(recp->N), d))\n        return 0;\n    BN_zero(&(recp->Nr));\n    recp->num_bits = BN_num_bits(d);\n    recp->shift = 0;\n    return 1;\n}', 'int BN_mod_mul_reciprocal(BIGNUM *r, const BIGNUM *x, const BIGNUM *y,\n                          BN_RECP_CTX *recp, BN_CTX *ctx)\n{\n    int ret = 0;\n    BIGNUM *a;\n    const BIGNUM *ca;\n    BN_CTX_start(ctx);\n    if ((a = BN_CTX_get(ctx)) == NULL)\n        goto err;\n    if (y != NULL) {\n        if (x == y) {\n            if (!BN_sqr(a, x, ctx))\n                goto err;\n        } else {\n            if (!BN_mul(a, x, y, ctx))\n                goto err;\n        }\n        ca = a;\n    } else\n        ca = x;\n    ret = BN_div_recp(NULL, r, ca, recp, ctx);\n err:\n    BN_CTX_end(ctx);\n    bn_check_top(r);\n    return ret;\n}', 'int BN_div_recp(BIGNUM *dv, BIGNUM *rem, const BIGNUM *m,\n                BN_RECP_CTX *recp, BN_CTX *ctx)\n{\n    int i, j, ret = 0;\n    BIGNUM *a, *b, *d, *r;\n    BN_CTX_start(ctx);\n    d = (dv != NULL) ? dv : BN_CTX_get(ctx);\n    r = (rem != NULL) ? rem : BN_CTX_get(ctx);\n    a = BN_CTX_get(ctx);\n    b = BN_CTX_get(ctx);\n    if (b == NULL)\n        goto err;\n    if (BN_ucmp(m, &(recp->N)) < 0) {\n        BN_zero(d);\n        if (!BN_copy(r, m)) {\n            BN_CTX_end(ctx);\n            return 0;\n        }\n        BN_CTX_end(ctx);\n        return 1;\n    }\n    i = BN_num_bits(m);\n    j = recp->num_bits << 1;\n    if (j > i)\n        i = j;\n    if (i != recp->shift)\n        recp->shift = BN_reciprocal(&(recp->Nr), &(recp->N), i, ctx);\n    if (recp->shift == -1)\n        goto err;\n    if (!BN_rshift(a, m, recp->num_bits))\n        goto err;\n    if (!BN_mul(b, a, &(recp->Nr), ctx))\n        goto err;\n    if (!BN_rshift(d, b, i - recp->num_bits))\n        goto err;\n    d->neg = 0;\n    if (!BN_mul(b, &(recp->N), d, ctx))\n        goto err;\n    if (!BN_usub(r, m, b))\n        goto err;\n    r->neg = 0;\n    j = 0;\n    while (BN_ucmp(r, &(recp->N)) >= 0) {\n        if (j++ > 2) {\n            BNerr(BN_F_BN_DIV_RECP, BN_R_BAD_RECIPROCAL);\n            goto err;\n        }\n        if (!BN_usub(r, r, &(recp->N)))\n            goto err;\n        if (!BN_add_word(d, 1))\n            goto err;\n    }\n    r->neg = BN_is_zero(r) ? 0 : m->neg;\n    d->neg = m->neg ^ recp->N.neg;\n    ret = 1;\n err:\n    BN_CTX_end(ctx);\n    bn_check_top(dv);\n    bn_check_top(rem);\n    return ret;\n}', 'BIGNUM *BN_CTX_get(BN_CTX *ctx)\n{\n    BIGNUM *ret;\n    CTXDBG_ENTRY("BN_CTX_get", ctx);\n    if (ctx->err_stack || ctx->too_many)\n        return NULL;\n    if ((ret = BN_POOL_get(&ctx->pool, ctx->flags)) == NULL) {\n        ctx->too_many = 1;\n        BNerr(BN_F_BN_CTX_GET, BN_R_TOO_MANY_TEMPORARY_VARIABLES);\n        return NULL;\n    }\n    BN_zero(ret);\n    ret->flags &= (~BN_FLG_CONSTTIME);\n    ctx->used++;\n    CTXDBG_RET(ctx, 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    a->flags &= ~BN_FLG_FIXED_TOP;\n    bn_check_top(a);\n    return 1;\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}', '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}']