PageFault error code now reports page presence correctly #1022
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Interesting find, this is a pretty serious bug.
I think you could avoid the extra function by moving the write/user checks down and combining them with the page table checks. I'll leave a suggestion in the review. I'll try to write some tests for this. |
copy
reviewed
Apr 20, 2024
If page directory was present and ring3 access or write protect caused page fault on page directory level, page precense was not checked. This patch adds this check and correctly reports page fault error.
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Done. |
copy
reviewed
Apr 21, 2024
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Thanks! |
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If page directory was present and ring3 access or write protection violation caused page fault on page directory level, page presence was not checked and it was assumed to be present.
This PR adds this check to correctly report present bit in page fault error codes.
I found this bug as my OS uses the present bit in error code of page fault as the initial requirement for demand paging.
This is my first time writing rust, so please tell me if something should be done differently.