OmniNX/Atmosphere
0
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases 1 Wiki Activity

kern: allocate the shadow stack

Browse Source
This commit is contained in:
Alula
2026-09-17 16:27:44 +02:00
parent f40b85cd5d
commit 4e917d700f
3 changed files with 40 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

33
libraries/libmesosphere/source/kern_k_thread.cpp
View File

@@ -214,6 +214,10 @@ namespace ams::kern {
m_tls_address = 0;
m_tls_heap_address = 0;
/* Set shadow stack address and page. */
m_shadow_stack_address = Null<KProcessAddress>;
m_shadow_stack_page = nullptr;
/* Set parent and condvar tree. */
m_parent = nullptr;
m_condvar_tree = nullptr;
@@ -281,6 +285,29 @@ namespace ams::kern {
R_TRY(owner->CreateThreadLocalRegion(std::addressof(m_tls_address)));
m_tls_heap_address = owner->GetThreadLocalRegionPointer(m_tls_address);
std::memset(m_tls_heap_address, 0, ams::svc::ThreadLocalRegionSize);
/* If the owning process has a shadow stack, allocate and map a page for this thread. */
if (owner->GetCreateProcessFlags() & ams::svc::CreateProcessFlag_EnableShadowStack) {
/* Allocate the backing page. */
KPageBuffer *page = KPageBuffer::AllocateChecked<PageSize>();
if (page == nullptr) {
owner->DeleteThreadLocalRegion(m_tls_address);
m_tls_address = Null<KProcessAddress>;
R_THROW(svc::ResultOutOfMemory());
}
/* If we fail to map the page, free it and undo the TLS region we just created. */
ON_RESULT_FAILURE {
KPageBuffer::Free(page);
owner->DeleteThreadLocalRegion(m_tls_address);
m_tls_address = Null<KProcessAddress>;
};
/* Map the page into the process's shadow stack region. */
R_TRY(owner->GetPageTable().MapPages(std::addressof(m_shadow_stack_address), 1, PageSize, page->GetPhysicalAddress(), KMemoryState_ShadowStack, KMemoryPermission_UserReadWrite));
m_shadow_stack_page = page;
}
}
/* Set parent, if relevant. */
@@ -390,6 +417,12 @@ namespace ams::kern {
m_parent->UnregisterThread(this);
}
/* If the thread has a shadow stack, unmap and free its page. */
if (m_shadow_stack_address != Null<KProcessAddress>) {
MESOSPHERE_R_ABORT_UNLESS(m_parent->GetPageTable().UnmapPages(m_shadow_stack_address, 1, KMemoryState_ShadowStack));
KPageBuffer::Free(m_shadow_stack_page);
}
/* If the thread has a local region, delete it. */
if (m_tls_address != Null<KProcessAddress>) {
m_parent->DeleteThreadLocalRegion(m_tls_address);