LibCrypto: Build with -fzero-call-used-regs=used#26657
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LucasChollet wants to merge 1 commit intoSerenityOS:masterfrom
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LibCrypto: Build with -fzero-call-used-regs=used#26657LucasChollet wants to merge 1 commit intoSerenityOS:masterfrom
LucasChollet wants to merge 1 commit intoSerenityOS:masterfrom
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By zeroing registers when returning from crypto functions, we prevent attackers from accessing sensitive information that could otherwise be left in these registers. Note that we currently have no safety regarding the same kind of leakage but with stack or heap memory. From some small experiments, the performance cost should be under 5%. This could probably be optimized by only applying it to the public API.
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By zeroing registers when returning from crypto functions, we prevent attackers from accessing sensitive information that could otherwise be left in these registers.
Note that we currently have no safety regarding the same kind of leakage but with stack or heap memory.
From some small experiments, the performance cost should be under 5%. This could probably be optimized by only applying it to the public API.
Before:
