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https://github.com/GrapheneOS/hardened_malloc.git
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30 lines
1.4 KiB
Markdown
30 lines
1.4 KiB
Markdown
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Very important and should be an easy sell:
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* improved robustness for high vma count on high memory machines
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* much higher `vm.max_map_count` by default
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* work on improving performance and resource usage with high vma count
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* add a way to disable the brk heap and have mmap grow upwards like it did in
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the past (preserving the same high base entropy)
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Somewhat important and an easy sell:
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* mremap flag to disable unmapping the source mapping
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* also needed by jemalloc for different reasons
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* not needed if the kernel gets first class support for arbitrarily sized
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guard pages and a virtual memory quarantine feature
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Fairly infeasible to land but could reduce overhead and extend coverage of
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security features to other code directly using mmap:
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* first class support for arbitrarily sized guard pages for mmap and mremap to
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eliminate half of the resulting VMAs and reduce 2 system calls to 1
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* not usable if it doesn't support mremap (shrink, grow, grow via move)
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* not usable if the guard page size is static
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* should support changing guard size for mremap growth via move
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* must be possible to set it up from the process
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* virtual memory quarantine
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* must be possible to set it up from the process
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* first-class support for aligned mappings with mmap and ideally mremap
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* not usable unless guard page support is provided and of course it has to
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work with this too
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