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Re: [PATCH, libgfortran] Add overflow check to xmalloc



>> On Tue, May 20, 2014 at 12:42 AM, Janne Blomqvist
>> <blomqvist.janne@gmail.com> wrote:
>>> On Thu, May 15, 2014 at 1:00 AM, Janne Blomqvist
>>> <blomqvist.janne@gmail.com> wrote:
>>>> Hi,
>>>>
>>>> a common malloc() pattern is "malloc(num_foo * sizeof(foo_t)", that
>>>> is, create space for an array of type foo_t with num_foo elements.
>>>> There is a slight danger here in that the multiplication can overflow
>>>> and wrap around, and then the caller thinks it has a larger array than
>>>> what malloc has actually created. The attached patch changes the
>>>> libgfortran xmalloc() function to have an API similar to calloc() with
>>>> two arguments, and the implementation checks for wraparound.
>>>
>>> Hello,
>>>
>>> attached is an updated patch which instead introduces a new function,
>>> xmallocarray, with the overflow check, and leaves the existing xmalloc
>>> as is. Thus avoiding the extra checking in the common case where one
>>> of the arguments to xmallocarray would be 1.
>>>
>>> Tested on x86_64-unknown-linux-gnu, Ok for trunk?
>>>

I would prefer if xcmalloc would not be named xmallocarray.

Thanks,

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