11.0.0-33: Difference between revisions

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The function which initializes a memalloc heap(FCRAM memregions + the container which the SlabHeap is under), had a major update. This uses XOR + rotation code, and it also uses svcGetSystemTick.

The svcGetSystemTick + XOR/rotation code mentioned above ~~seems to be~~ a new security feature for the kernel heaps(see above). However, it's unknown how much the svcGetSystemTick() output really varies if anything(?) for each hard-boot during initialization of the heaps.

The svcGetSystemTick + XOR/rotation code mentioned above is a new security feature for the kernel heaps(see above). This is intended to stop non-arm11kernel from modifying kernel heap [[Memory_Management#MemoryBlockHeader|memchunkhdrs]]. However, it's unknown how much the svcGetSystemTick() output really varies if anything(?) for each hard-boot during initialization of the heaps.

6 memory management functions were updated to use the above new functions, these func-calls replaced the validation code previously used in these functions in some cases. These were also updated for the above heap security implementation. One function had a validation func-call added where previously there wasn't any validation done in the beginning of the function for previous versions.

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 The function which initializes a memalloc heap(FCRAM memregions + the container which the SlabHeap is under), had a major update. This uses XOR + rotation code, and it also uses svcGetSystemTick.
-The svcGetSystemTick + XOR/rotation code mentioned above seems to be a new security feature for the kernel heaps(see above). However, it's unknown how much the svcGetSystemTick() output really varies if anything(?) for each hard-boot during initialization of the heaps.
+The svcGetSystemTick + XOR/rotation code mentioned above is a new security feature for the kernel heaps(see above). This is intended to stop non-arm11kernel from modifying kernel heap [[Memory_Management#MemoryBlockHeader|memchunkhdrs]]. However, it's unknown how much the svcGetSystemTick() output really varies if anything(?) for each hard-boot during initialization of the heaps.
 memory management functions were updated to use the above new functions, these func-calls replaced the validation code previously used in these functions in some cases. These were also updated for the above heap security implementation. One function had a validation func-call added where previously there wasn't any validation done in the beginning of the function for previous versions.