crypto/x509/x509_vfy.c:1723: error: NULL_DEREFERENCE
  pointer `xs` last assigned on line 1710 could be null and is dereferenced at line 1723, column 8.
Showing all 35 steps of the trace


crypto/x509/x509_vfy.c:1681:1: start of procedure internal_verify()
1679.   	}
1680.   
1681. > static int internal_verify(X509_STORE_CTX *ctx)
1682.   	{
1683.   	int ok=0,n;

crypto/x509/x509_vfy.c:1683:2: 
1681.   static int internal_verify(X509_STORE_CTX *ctx)
1682.   	{
1683. > 	int ok=0,n;
1684.   	X509 *xs,*xi;
1685.   	EVP_PKEY *pkey=NULL;

crypto/x509/x509_vfy.c:1685:2: 
1683.   	int ok=0,n;
1684.   	X509 *xs,*xi;
1685. > 	EVP_PKEY *pkey=NULL;
1686.   	int (*cb)(int xok,X509_STORE_CTX *xctx);
1687.   

crypto/x509/x509_vfy.c:1688:2: 
1686.   	int (*cb)(int xok,X509_STORE_CTX *xctx);
1687.   
1688. > 	cb=ctx->verify_cb;
1689.   
1690.   	n=sk_X509_num(ctx->chain);

crypto/x509/x509_vfy.c:1690:4: Condition is true
1688.   	cb=ctx->verify_cb;
1689.   
1690.   	n=sk_X509_num(ctx->chain);
           ^
1691.   	ctx->error_depth=n-1;
1692.   	n--;

crypto/x509/x509_vfy.c:1690:2: 
1688.   	cb=ctx->verify_cb;
1689.   
1690. > 	n=sk_X509_num(ctx->chain);
1691.   	ctx->error_depth=n-1;
1692.   	n--;

crypto/stack/stack.c:294:1: start of procedure sk_num()
  292.   	}
  293.   
  294. > int sk_num(const _STACK *st)
  295.   {
  296.   	if(st == NULL) return -1;

crypto/stack/stack.c:296:5: Taking false branch
  294.   int sk_num(const _STACK *st)
  295.   {
  296.   	if(st == NULL) return -1;
             ^
  297.   	return st->num;
  298.   }

crypto/stack/stack.c:297:2: 
  295.   {
  296.   	if(st == NULL) return -1;
  297. > 	return st->num;
  298.   }
  299.   

crypto/stack/stack.c:298:1: return from a call to sk_num
  296.   	if(st == NULL) return -1;
  297.   	return st->num;
  298. > }
  299.   
  300.   void *sk_value(const _STACK *st, int i)

crypto/x509/x509_vfy.c:1691:2: 
1689.   
1690.   	n=sk_X509_num(ctx->chain);
1691. > 	ctx->error_depth=n-1;
1692.   	n--;
1693.   	xi=sk_X509_value(ctx->chain,n);

crypto/x509/x509_vfy.c:1692:2: 
1690.   	n=sk_X509_num(ctx->chain);
1691.   	ctx->error_depth=n-1;
1692. > 	n--;
1693.   	xi=sk_X509_value(ctx->chain,n);
1694.   

crypto/x509/x509_vfy.c:1693:5: Condition is true
1691.   	ctx->error_depth=n-1;
1692.   	n--;
1693.   	xi=sk_X509_value(ctx->chain,n);
            ^
1694.   
1695.   	if (ctx->check_issued(ctx, xi, xi))

crypto/x509/x509_vfy.c:1693:2: 
1691.   	ctx->error_depth=n-1;
1692.   	n--;
1693. > 	xi=sk_X509_value(ctx->chain,n);
1694.   
1695.   	if (ctx->check_issued(ctx, xi, xi))

crypto/stack/stack.c:300:1: start of procedure sk_value()
  298.   }
  299.   
  300. > void *sk_value(const _STACK *st, int i)
  301.   {
  302.   	if(!st || (i < 0) || (i >= st->num)) return NULL;

crypto/stack/stack.c:302:6: Taking false branch
  300.   void *sk_value(const _STACK *st, int i)
  301.   {
  302.   	if(!st || (i < 0) || (i >= st->num)) return NULL;
              ^
  303.   	return st->data[i];
  304.   }

crypto/stack/stack.c:302:13: Taking false branch
  300.   void *sk_value(const _STACK *st, int i)
  301.   {
  302.   	if(!st || (i < 0) || (i >= st->num)) return NULL;
                     ^
  303.   	return st->data[i];
  304.   }

crypto/stack/stack.c:302:24: Taking false branch
  300.   void *sk_value(const _STACK *st, int i)
  301.   {
  302.   	if(!st || (i < 0) || (i >= st->num)) return NULL;
                                ^
  303.   	return st->data[i];
  304.   }

crypto/stack/stack.c:303:2: 
  301.   {
  302.   	if(!st || (i < 0) || (i >= st->num)) return NULL;
  303. > 	return st->data[i];
  304.   }
  305.   

crypto/stack/stack.c:304:1: return from a call to sk_value
  302.   	if(!st || (i < 0) || (i >= st->num)) return NULL;
  303.   	return st->data[i];
  304. > }
  305.   
  306.   void *sk_set(_STACK *st, int i, void *value)

crypto/x509/x509_vfy.c:1695:6: Taking false branch
1693.   	xi=sk_X509_value(ctx->chain,n);
1694.   
1695.   	if (ctx->check_issued(ctx, xi, xi))
             ^
1696.   		xs=xi;
1697.   	else

crypto/x509/x509_vfy.c:1699:7: Taking false branch
1697.   	else
1698.   		{
1699.   		if (n <= 0)
              ^
1700.   			{
1701.   			ctx->error=X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE;

crypto/x509/x509_vfy.c:1708:4: 
1706.   		else
1707.   			{
1708. > 			n--;
1709.   			ctx->error_depth=n;
1710.   			xs=sk_X509_value(ctx->chain,n);

crypto/x509/x509_vfy.c:1709:4: 
1707.   			{
1708.   			n--;
1709. > 			ctx->error_depth=n;
1710.   			xs=sk_X509_value(ctx->chain,n);
1711.   			}

crypto/x509/x509_vfy.c:1710:7: Condition is true
1708.   			n--;
1709.   			ctx->error_depth=n;
1710.   			xs=sk_X509_value(ctx->chain,n);
              ^
1711.   			}
1712.   		}

crypto/x509/x509_vfy.c:1710:4: 
1708.   			n--;
1709.   			ctx->error_depth=n;
1710. > 			xs=sk_X509_value(ctx->chain,n);
1711.   			}
1712.   		}

crypto/stack/stack.c:300:1: start of procedure sk_value()
  298.   }
  299.   
  300. > void *sk_value(const _STACK *st, int i)
  301.   {
  302.   	if(!st || (i < 0) || (i >= st->num)) return NULL;

crypto/stack/stack.c:302:6: Taking false branch
  300.   void *sk_value(const _STACK *st, int i)
  301.   {
  302.   	if(!st || (i < 0) || (i >= st->num)) return NULL;
              ^
  303.   	return st->data[i];
  304.   }

crypto/stack/stack.c:302:13: Taking false branch
  300.   void *sk_value(const _STACK *st, int i)
  301.   {
  302.   	if(!st || (i < 0) || (i >= st->num)) return NULL;
                     ^
  303.   	return st->data[i];
  304.   }

crypto/stack/stack.c:302:24: Taking true branch
  300.   void *sk_value(const _STACK *st, int i)
  301.   {
  302.   	if(!st || (i < 0) || (i >= st->num)) return NULL;
                                ^
  303.   	return st->data[i];
  304.   }

crypto/stack/stack.c:302:39: 
  300.   void *sk_value(const _STACK *st, int i)
  301.   {
  302. > 	if(!st || (i < 0) || (i >= st->num)) return NULL;
  303.   	return st->data[i];
  304.   }

crypto/stack/stack.c:304:1: return from a call to sk_value
  302.   	if(!st || (i < 0) || (i >= st->num)) return NULL;
  303.   	return st->data[i];
  304. > }
  305.   
  306.   void *sk_set(_STACK *st, int i, void *value)

crypto/x509/x509_vfy.c:1715:9: Loop condition is true. Entering loop body
1713.   
1714.   /*	ctx->error=0;  not needed */
1715.   	while (n >= 0)
                ^
1716.   		{
1717.   		ctx->error_depth=n;

crypto/x509/x509_vfy.c:1717:3: 
1715.   	while (n >= 0)
1716.   		{
1717. > 		ctx->error_depth=n;
1718.   
1719.   		/* Skip signature check for self signed certificates unless

crypto/x509/x509_vfy.c:1723:8: Taking false branch
1721.   		 * just wastes time.
1722.   		 */
1723.   		if (!xs->valid && (xs != xi || (ctx->param->flags & X509_V_FLAG_CHECK_SS_SIGNATURE)))
               ^
1724.   			{
1725.   			if ((pkey=X509_get_pubkey(xi)) == NULL)

static int internal_verify(X509_STORE_CTX *ctx)
	{
	int ok=0,n;
	X509 *xs,*xi;
	EVP_PKEY *pkey=NULL;
	int (*cb)(int xok,X509_STORE_CTX *xctx);
	cb=ctx->verify_cb;
	n=sk_X509_num(ctx->chain);
	ctx->error_depth=n-1;
	n--;
	xi=sk_X509_value(ctx->chain,n);
	if (ctx->check_issued(ctx, xi, xi))
		xs=xi;
	else
		{
		if (n <= 0)
			{
			ctx->error=X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE;
			ctx->current_cert=xi;
			ok=cb(0,ctx);
			goto end;
			}
		else
			{
			n--;
			ctx->error_depth=n;
			xs=sk_X509_value(ctx->chain,n);
			}
		}
	while (n >= 0)
		{
		ctx->error_depth=n;
		if (!xs->valid && (xs != xi || (ctx->param->flags & X509_V_FLAG_CHECK_SS_SIGNATURE)))
			{
			if ((pkey=X509_get_pubkey(xi)) == NULL)
				{
				ctx->error=X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY;
				ctx->current_cert=xi;
				ok=(*cb)(0,ctx);
				if (!ok) goto end;
				}
			else if (X509_verify(xs,pkey) <= 0)
				{
				ctx->error=X509_V_ERR_CERT_SIGNATURE_FAILURE;
				ctx->current_cert=xs;
				ok=(*cb)(0,ctx);
				if (!ok)
					{
					EVP_PKEY_free(pkey);
					goto end;
					}
				}
			EVP_PKEY_free(pkey);
			pkey=NULL;
			}
		xs->valid = 1;
		ok = check_cert_time(ctx, xs);
		if (!ok)
			goto end;
		ctx->current_issuer=xi;
		ctx->current_cert=xs;
		ok=(*cb)(1,ctx);
		if (!ok) goto end;
		n--;
		if (n >= 0)
			{
			xi=xs;
			xs=sk_X509_value(ctx->chain,n);
			}
		}
	ok=1;
end:
	return ok;
	}
['static int internal_verify(X509_STORE_CTX *ctx)\n\t{\n\tint ok=0,n;\n\tX509 *xs,*xi;\n\tEVP_PKEY *pkey=NULL;\n\tint (*cb)(int xok,X509_STORE_CTX *xctx);\n\tcb=ctx->verify_cb;\n\tn=sk_X509_num(ctx->chain);\n\tctx->error_depth=n-1;\n\tn--;\n\txi=sk_X509_value(ctx->chain,n);\n\tif (ctx->check_issued(ctx, xi, xi))\n\t\txs=xi;\n\telse\n\t\t{\n\t\tif (n <= 0)\n\t\t\t{\n\t\t\tctx->error=X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE;\n\t\t\tctx->current_cert=xi;\n\t\t\tok=cb(0,ctx);\n\t\t\tgoto end;\n\t\t\t}\n\t\telse\n\t\t\t{\n\t\t\tn--;\n\t\t\tctx->error_depth=n;\n\t\t\txs=sk_X509_value(ctx->chain,n);\n\t\t\t}\n\t\t}\n\twhile (n >= 0)\n\t\t{\n\t\tctx->error_depth=n;\n\t\tif (!xs->valid && (xs != xi || (ctx->param->flags & X509_V_FLAG_CHECK_SS_SIGNATURE)))\n\t\t\t{\n\t\t\tif ((pkey=X509_get_pubkey(xi)) == NULL)\n\t\t\t\t{\n\t\t\t\tctx->error=X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY;\n\t\t\t\tctx->current_cert=xi;\n\t\t\t\tok=(*cb)(0,ctx);\n\t\t\t\tif (!ok) goto end;\n\t\t\t\t}\n\t\t\telse if (X509_verify(xs,pkey) <= 0)\n\t\t\t\t{\n\t\t\t\tctx->error=X509_V_ERR_CERT_SIGNATURE_FAILURE;\n\t\t\t\tctx->current_cert=xs;\n\t\t\t\tok=(*cb)(0,ctx);\n\t\t\t\tif (!ok)\n\t\t\t\t\t{\n\t\t\t\t\tEVP_PKEY_free(pkey);\n\t\t\t\t\tgoto end;\n\t\t\t\t\t}\n\t\t\t\t}\n\t\t\tEVP_PKEY_free(pkey);\n\t\t\tpkey=NULL;\n\t\t\t}\n\t\txs->valid = 1;\n\t\tok = check_cert_time(ctx, xs);\n\t\tif (!ok)\n\t\t\tgoto end;\n\t\tctx->current_issuer=xi;\n\t\tctx->current_cert=xs;\n\t\tok=(*cb)(1,ctx);\n\t\tif (!ok) goto end;\n\t\tn--;\n\t\tif (n >= 0)\n\t\t\t{\n\t\t\txi=xs;\n\t\t\txs=sk_X509_value(ctx->chain,n);\n\t\t\t}\n\t\t}\n\tok=1;\nend:\n\treturn ok;\n\t}', 'int sk_num(const _STACK *st)\n{\n\tif(st == NULL) return -1;\n\treturn st->num;\n}', 'void *sk_value(const _STACK *st, int i)\n{\n\tif(!st || (i < 0) || (i >= st->num)) return NULL;\n\treturn st->data[i];\n}']