[ros-dev] Re: [ros-svn] [weiden] 13138: implemented the ProcessSessionInformation information class

[Joseph Galbraith]

>> Do MmCopyFrom/ToCaller use SEH?
>>
>> If not, both are necessary.  Using SEH protects from another
>> thread in the process (or some other component) free the VM
>> page and cause a crash.
>>
>> So not only must the address be checked to make sure it
>> is a user mode address iff the caller is user mode, but
>> the parameter need to be copied using SEH; otherwise
>> what was just probed as valid may become invalid before
>> the copy can be done.
> 
> 
> Yes... and no...
> 
> our exception handler has a special-case for MmCopyFrom/MmCopyTo.
> 
> The upshot is that those two functions have SEH without explicitly 
> needing to setup an SEH frame for it.

Fascinating... that I would have never guessed.

Thanks,

Joseph