Kernel: Make Region's physical page accessors safer to use

Region::physical_page() now takes the VMObject lock while accessing the
physical pages array, and returns a RefPtr<PhysicalPage>. This ensures
that the array access is safe.

Region::physical_page_slot() now VERIFY()'s that the VMObject lock is
held by the caller. Since we're returning a reference to the physical
page slot in the VMObject's physical page array, this is the best we
can do here.

1 files changed, 1 insertions, 1 deletions

diff --git a/Kernel/ProcessSpecificExposed.cpp b/Kernel/ProcessSpecificExposed.cpp
index 14eb1db680..86359a78a0 100644
--- a/Kernel/ProcessSpecificExposed.cpp
+++ b/Kernel/ProcessSpecificExposed.cpp
@@ -293,7 +293,7 @@ ErrorOr<void> Process::procfs_get_virtual_memory_stats(KBufferBuilder& builder)
 
             StringBuilder pagemap_builder;
             for (size_t i = 0; i < region.page_count(); ++i) {
-                auto const* page = region.physical_page(i);
+                auto page = region.physical_page(i);
                 if (!page)
                     pagemap_builder.append('N');
                 else if (page->is_shared_zero_page() || page->is_lazy_committed_page())