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Use unsigned intptr_t type for framebuffer addresses

Authored by jhibbits on Dec 2 2017, 1:48 AM.



Some architectures (powerpc Book-E) have a vm_paddr_t larger than intptr_t.
Casting from the intptr_t to vm_paddr_t causes sign extension, leading to a
potentially invalid address.

This was seen when running X on a PowerPC P1022 machine, which mapped the
backing framebuffer at 0xc1800000. When mmap()d by X, this yielded an invalid
address of 0xffffffffc1800000, or, as the hardware would see it, 0xfc1800000.

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Event Timeline

jhibbits created this revision.Dec 2 2017, 1:48 AM
ray accepted this revision.Dec 5 2017, 11:03 PM

Correct. Thank you!

This revision is now accepted and ready to land.Dec 5 2017, 11:03 PM
This revision was automatically updated to reflect the committed changes.