Re: [PATCH] gdb: fix overflow caused by value_print_array_elements

[Tom Tromey <tom@tromey.com>]

>>>>> Stephan Rohr <stephan.rohr@intel.com> writes:

Thanks for the patch.

> From: "Rohr, Stephan" <stephan.rohr@intel.com>
> When printing an array whose stride is larger than its element type,
> GDB allocates memory for each array element based on the element's
> true type.  The allocated buffer may include some padding.
> "value_print_array_elements ()" passes the stride as the bit length to
> "from_component_bitsize ()".  This is silently swallowed if the stride
> does not exceed the size of the allocated buffer but corrupts the heap
> if the write goes beyond.  Pass the size of the element's true type
> ^instead.

Stray "^" here.

> +
> +  /* For packed arrays, the stride may be smaller than the element's target
> +     type.  */
> +  ULONGEST elt_bits = std::min (bit_stride,
> +				8 * check_typedef (elttype)->length ());

I think it would be good if the test case included a case where the
stride is smaller than the element's type.  I think currently it only
tests the case where the element type is smaller than the stride.

Tom