Re: [PATCH v2] drm/gem: Fix mmap fake offset handling for drm_gem_object_funcs.mmap

Hi,

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I think for ttm just consistently using the one per-device mapping for everything, with all the fake offsets, is probably the quickest route.

Hmm, not clear how to fit dmabufs into this. dmabufs already have their own file, inode and address space. I'm not sure you can switch that over to the per-device mapping in the first place, and even if you can I have my doubts this is a good idea from a security point of view ...

You can (plenty drivers do that already),

Have pointer(s) to code?

and not sure how that breaks security?

Go try mmap(fake-offset) on the dma-buf file handle to access other buffers of the drm device? Hmm, thinking again, I guess the verify-access restrictions should prevent that.

cheers, Gerd