Re: [win32] wrong solib from/to addresses

Christopher Faylor
2007-06-13T02:21:52Z

On Wed, Jun 13, 2007 at 12:32:55AM +0100, Pedro Alves wrote:
> Hi Joel,
>
> Joel Brobecker wrote:
>> We are working on porting our product to Vista, and we have noticed
>> an issue that this version of the MS OS makes more apparent: The from/to
>> addresses printed in the "info shared" listing are correct only when
>> the DLL was loaded at the prefered load address (which is in the
>> ImageBase field of the COFF/PE header).
>> I collegue of mine told me that, for security reasons, system DLLs
>> on Vista are now always rebased, and thus, the information printed
>> by info based is off by a certain offset.
>> The core of the attached patch is to implement the target_so_ops
>> method relocate_section_addresses. For that, I needed to compute
>> the offset between the load address and the image_base, and store
>> it for later use (during the call of our routine above). There
>> were two challenges:
>> 1. Compute this image base. Rather than dig into the COFF/PE
>> data, I took a simpler route that I think has already been
>> taken: Use the start address of the .text section. I think
>> this is already used to do the symbol relocation.
>> 2. Make that information available: I found that the lm_info
>> field was not allocated, so I had to add its initialization.
>> With all these changes, the address are correct again.
>
>
> I had a similar patch here, that I dumped in favor of a rewrite
> of win32 solibs on top of Daniel's pending solib-target.c.

That sounds like the right way to go to me. Can we hold of on this
until Daniel's changes are in?

cgf