Security: Avoid casting int64_t to intptr_t

[turnidge]

DartUtils::GetIntegerValue in runtime/bin/dartutils.cc returns an int64_t, but is being implicitly cast down to an intptr_t in some places (e.g. Socket_ReadList)

We should look for other occurrences of this as well.

...

Also possibly:

Dart_ListLength:
          *len = integer.AsInt64Value(); // WRONG

[DartBot]

This comment was originally written by swn...@gmail.com

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I have no idea if this issue is related with previous issued, but I found this with int64:

This script calculates power 12 by 100.

Exception arises and stop the execution for remaining lines:
Exception: Dart_IntegerToInt64: Integer 828179745220145502584084235957368498016122811853894435464201864103254919330121223037770283296858019385573376 cannot be represented as an int64_t.
Stack Trace: 0. Function: 'ConsoleImplementation._log@1c3f8015' url: '/mnt/data/b/build/slave/dartium-lucid64-inc/build/src/out/Release/obj/gen/webkit/bindings/dart/generated/dart/ConsoleImplementation.dart' line:91 col:3
 1. Function: 'ConsoleImplementation.log' url: '/mnt/data/b/build/slave/dartium-lucid64-inc/build/src/out/Release/obj/gen/webkit/bindings/dart/generated/dart/ConsoleImplementation.dart' line:85 col:9
 2. Function: '::print' url: 'dart:builtin' line:5 col:21
 3. Function: '::main' url: 'http://localhost/testlab/dartproject/helloworld.dart' line:54 col:18

[DartBot]

This comment was originally written by swnd.tan...@gmail.com

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I have to make clear that the issue from me is not from the Dart VM, but on Dartium.

Here is the full script that failed on Dartium, succeed on Dart VM:
    #import( 'dart:core' );
    num power( num x, num exponent )
    {
        num result = x;
        for( var i=1; i<exponent; ++i ) result *= x;
        
        return result;
    }
    
    void main()
    {
        var list = [ 1, 2, 3, 4, 5, 100, 2000, 90000 ];
        
        for( var x in list )
        {
            print( power( 12, x ) );
        }
    }

[DartBot]

This comment was originally written by antonm@google.com

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@swnd.tan: that's a different issue---we're currently not quite correct with dealing with huge numbers. I am going to fix it asap.

[iposva-google]

Added Security label.

[iposva-google]

Added this to the M1 milestone.

[turnidge]

Set owner to @lexprfuncall.

[lexprfuncall]

Narrowing conversions from intptr_t to int64_t can be discovered by the compiler if the -Wconversion flag is added to cflags in tools/gyp/configurations_make.gypi.

It would be great to enable this flag globally. However, there are many other potentially dangerous conversions reported, including certain conversions with sign mismatches. These must all be addressed.

[lexprfuncall]

The Dart_ListLength issue has been resolved.

http://codereview.chromium.org/10941018/

Reviewing the compiler output after enabling -Wconversion shows that the standalone Dart is the primary offender. Issue #1 has been created to address the underlying cause of these conversions. Once that is addressed we can remove the unsafe integer access method from the API.

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Added Started label.
Marked this as being blocked by #5301.

[iposva-google]

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[iposva-google]

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[iposva-google]

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[iposva-google]

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[larsbak]

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[iposva-google]

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[iposva-google]

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