[PATCH] krnl386.exe16: Fix NULL pointer dereferencing

[Stefan Dösinger]

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Am 2015-03-27 um 19:16 schrieb Sergey Isakov:
> This if statement body will perform only if driver_request is NULL 
> pointer. Next statements will cause crash. Bug 38159 NULL pointer
> dereferencing <https://bugs.winehq.org/show_bug.cgi?id=38159>
I think in this case the segfault is intentional. The caller passes a
stupid parameter. Also I'm not sure if it actually segfaults. In vm86
mode memory is mapped to this page, so NULL may be a valid address.

The best solution would be to write a test and see what happens on an
ancient DOS, but we don't have a test infrastructure for DOS and
Win16. The next best idea might be to just remove the entire block.
It's funny though since (according to git) the patch that added this
check already added the "/* FIXME - to be deleted ?? */" comment.

At some point we may as well remove the entire DOS code since we just
call dosbox these days and 64 bit CPUs don't allow vm86 mode anyway.
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