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Kernel: Set NX bit on expanded kmalloc memory mappings if supported

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We never want to execute kmalloc memory.
This commit is contained in:
Andreas Kling 2021-12-25 19:55:52 +01:00
parent da5c257e2e
commit 4d585cdb82
1 changed files with 4 additions and 0 deletions
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4
Kernel/Heap/kmalloc.cpp
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@ -127,6 +127,8 @@ struct KmallocGlobalData {
expansion_data->next_virtual_address = expansion_data->next_virtual_address.offset(new_subheap_size); expansion_data->next_virtual_address = expansion_data->next_virtual_address.offset(new_subheap_size);
auto cpu_supports_nx = Processor::current().has_feature(CPUFeature::NX);
SpinlockLocker mm_locker(Memory::s_mm_lock); SpinlockLocker mm_locker(Memory::s_mm_lock);
SpinlockLocker pd_locker(MM.kernel_page_directory().get_lock()); SpinlockLocker pd_locker(MM.kernel_page_directory().get_lock());
@ -146,6 +148,8 @@ struct KmallocGlobalData {
pte->set_global(true); pte->set_global(true);
pte->set_user_allowed(false); pte->set_user_allowed(false);
pte->set_writable(true); pte->set_writable(true);
if (cpu_supports_nx)
pte->set_execute_disabled(true);
pte->set_present(true); pte->set_present(true);
} }