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Kernel: Mark write_cr0() and write_cr4() as UNMAP_AFTER_INIT

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This removes a very useful tool for attackers trying to disable
SMAP/SMEP/etc. :^)
This commit is contained in:
Andreas Kling 2021-02-19 18:25:28 +01:00
parent 6136faa4eb
commit 32e93c8808
1 changed files with 2 additions and 2 deletions
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4
Kernel/Arch/i386/CPU.cpp
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@ -720,12 +720,12 @@ void exit_trap(TrapFrame* trap)
return Processor::current().exit_trap(*trap); return Processor::current().exit_trap(*trap);
} }
void write_cr0(u32 value) NEVER_INLINE UNMAP_AFTER_INIT void write_cr0(u32 value)
{ {
asm volatile("movl %%eax, %%cr0" ::"a"(value)); asm volatile("movl %%eax, %%cr0" ::"a"(value));
} }
void write_cr4(u32 value) NEVER_INLINE UNMAP_AFTER_INIT void write_cr4(u32 value)
{ {
asm volatile("movl %%eax, %%cr4" ::"a"(value)); asm volatile("movl %%eax, %%cr4" ::"a"(value));
} }