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On version [[1.0.0]], the initial binaries loaded into memory by the kernel always have the upper 32-bits as all-zero, so there are 6 fewer bits of layout randomization.
On version [[1.0.0]], the initial binaries loaded into memory by the kernel always have the upper 32-bits as all-zero, so there are 6 fewer bits of layout randomization.
= Kernel Implementation of Userland ASLR =
== 1.0.0 ==
if (AddressSpaceType == 2) {
BaseAddr = 0x80000000; // 64-bit
RandomMax = 0x6400;
}
else {
BaseAddr = 0x40000000; // 32-bit
RandomMax = 0x200;
}
if (AddressSpaceType == 4) {
MapRegionSize = 0;
HeapRegionSize = 0x80000000;
}
else {
MapRegionSize = 0x40000000;
HeapRegionSize = 0x40000000;
}
if (EnableAslr) {
rnd0 = GetRandomRange(0, RandomMax) << 21;
rnd1 = GetRandomRange(0, RandomMax) << 21;
}
else {
rnd0 = rnd1 = 0;
}
this->MapBaseAddr = BaseAddr + min(rnd0, rnd1)
this->HeapRegionBaseAddr = this->MapBaseAddr + MapRegionSize + max(rnd0, rnd1) - min(rnd0, rnd1)
==TLS==
==TLS==