Re:The cats sitting on a fence in early builds of Windows 8
by fredoralive on Wednesday February 23, 2022 @06:56AM
(#30440130)
AFAIK stuff like .net's WPF and the GPU accelerated DirectWrite do font rendering in userspace. It's ye olde GDI that is in the kernel, because NT didn't run well on a 486[1]. Yes, Windows has about 5 different ways to render fonts, and no, they don't seem to render fonts the same way.
(In the case of this kernel text mode / BSOD code, I do wonder does it use the GDI font rendering, or does it have its own separate mini renderer just for those screens?)
[1] Probably a bit of a simplification, I know.
Re:The cats sitting on a fence in early builds of Windows 8
by formerly_proven on Wednesday February 23, 2022 @10:43AM
(#30442248)
I don't know anything about DirectWrite, but there seems to be a DirectWrite kernel component due to CVE-2020-1577 (DirectWrite leaking kernel memory "by convincing a user to visit an untrusted webpage", which I'm not sure whether the exploit route would be in TTF/OTF processing, e.g. due to webfonts, or the text rendering itself).
Re:The cats sitting on a fence in early builds of Windows 8
by raverbashing on Wednesday February 23, 2022 @03:36AM
(#30439016)
I stand corrected then! (Unless this changed recently)
https://googleprojectzero.blogspot.com/2016/06/a-year-of-win...
Re:The cats sitting on a fence in early builds of Windows 8
by zinekeller on Wednesday February 23, 2022 @07:37AM
(#30440348)
I mean, in recent version of Windows it's now on the user-space, but because Microsoft retains bug-for-bug compatibility Windows 8 will be stuck with a kernel font rasteriser*
* DirectWrite and WPF have been always user-space.
Oh but it does. Most (all?) text rendering on Windows happens in the kernel.