diff --git a/Kernel/Memory/AddressSpace.cpp b/Kernel/Memory/AddressSpace.cpp
index dabf79d346..7f577a78d1 100644
--- a/Kernel/Memory/AddressSpace.cpp
+++ b/Kernel/Memory/AddressSpace.cpp
@@ -80,7 +80,10 @@ KResult AddressSpace::unmap_mmap_range(VirtualAddress addr, size_t size)
 
         // And finally we map the new region(s) using our page directory (they were just allocated and don't have one).
         for (auto* new_region : new_regions) {
-            new_region->map(page_directory());
+            // TODO: Ideally we should do this in a way that can be rolled back on failure, as failing here
+            // leaves the caller in an undefined state.
+            if (!new_region->map(page_directory()))
+                return ENOMEM;
         }
 
         PerformanceManager::add_unmap_perf_event(Process::current(), range_to_unmap);
@@ -130,7 +133,10 @@ KResult AddressSpace::unmap_mmap_range(VirtualAddress addr, size_t size)
 
     // And finally map the new region(s) into our page directory.
     for (auto* new_region : new_regions) {
-        new_region->map(page_directory());
+        // TODO: Ideally we should do this in a way that can be rolled back on failure, as failing here
+        // leaves the caller in an undefined state.
+        if (!new_region->map(page_directory()))
+            return ENOMEM;
     }
 
     PerformanceManager::add_unmap_perf_event(Process::current(), range_to_unmap);
diff --git a/Kernel/Memory/MemoryManager.cpp b/Kernel/Memory/MemoryManager.cpp
index 324f9cb083..9e5ad39175 100644
--- a/Kernel/Memory/MemoryManager.cpp
+++ b/Kernel/Memory/MemoryManager.cpp
@@ -748,7 +748,8 @@ OwnPtr<Region> MemoryManager::allocate_kernel_region_with_vmobject(VirtualRange
         return {};
 
     auto region = maybe_region.release_value();
-    region->map(kernel_page_directory());
+    if (!region->map(kernel_page_directory()))
+        return {};
     return region;
 }
 
diff --git a/Kernel/Memory/Region.cpp b/Kernel/Memory/Region.cpp
index c232e1bb7d..7130f1c5ff 100644
--- a/Kernel/Memory/Region.cpp
+++ b/Kernel/Memory/Region.cpp
@@ -285,7 +285,8 @@ bool Region::map(PageDirectory& page_directory, ShouldFlushTLB should_flush_tlb)
 void Region::remap()
 {
     VERIFY(m_page_directory);
-    map(*m_page_directory);
+    auto result = map(*m_page_directory);
+    VERIFY(result);
 }
 
 PageFaultResponse Region::handle_fault(PageFault const& fault)
@@ -310,7 +311,8 @@ PageFaultResponse Region::handle_fault(PageFault const& fault)
             auto page_index_in_vmobject = translate_to_vmobject_page(page_index_in_region);
             VERIFY(m_vmobject->is_anonymous());
             page_slot = static_cast<AnonymousVMObject&>(*m_vmobject).allocate_committed_page({});
-            remap_vmobject_page(page_index_in_vmobject);
+            if (!remap_vmobject_page(page_index_in_vmobject))
+                return PageFaultResponse::OutOfMemory;
             return PageFaultResponse::Continue;
         }
         dbgln("BUG! Unexpected NP fault at {}", fault.vaddr());
@@ -458,7 +460,9 @@ PageFaultResponse Region::handle_inode_fault(size_t page_index_in_region)
         MM.unquickmap_page();
     }
 
-    remap_vmobject_page(page_index_in_vmobject);
+    if (!remap_vmobject_page(page_index_in_vmobject))
+        return PageFaultResponse::OutOfMemory;
+
     return PageFaultResponse::Continue;
 }
 
diff --git a/Kernel/Syscalls/fork.cpp b/Kernel/Syscalls/fork.cpp
index df64f4f12e..ee3c7ca2a6 100644
--- a/Kernel/Syscalls/fork.cpp
+++ b/Kernel/Syscalls/fork.cpp
@@ -109,7 +109,8 @@ KResultOr<FlatPtr> Process::sys$fork(RegisterState& regs)
                 // TODO: tear down new process?
                 return ENOMEM;
             }
-            child_region->map(child->address_space().page_directory(), Memory::ShouldFlushTLB::No);
+            if (!child_region->map(child->address_space().page_directory(), Memory::ShouldFlushTLB::No))
+                return ENOMEM;
 
             if (region == m_master_tls_region.unsafe_ptr())
                 child->m_master_tls_region = child_region;
diff --git a/Kernel/Syscalls/mmap.cpp b/Kernel/Syscalls/mmap.cpp
index 4ad3550bb2..6fcd86d2ae 100644
--- a/Kernel/Syscalls/mmap.cpp
+++ b/Kernel/Syscalls/mmap.cpp
@@ -347,7 +347,7 @@ KResultOr<FlatPtr> Process::sys$mprotect(Userspace<void*> addr, size_t size, int
         }
 
         // Remove the old region from our regions tree, since were going to add another region
-        // with the exact same start address, but dont deallocate it yet
+        // with the exact same start address, but do not deallocate it yet
         auto region = address_space().take_region(*old_region);
 
         // Unmap the old region here, specifying that we *don't* want the VM deallocated.
@@ -371,9 +371,11 @@ KResultOr<FlatPtr> Process::sys$mprotect(Userspace<void*> addr, size_t size, int
 
         // Map the new regions using our page directory (they were just allocated and don't have one).
         for (auto* adjacent_region : adjacent_regions) {
-            adjacent_region->map(address_space().page_directory());
+            if (!adjacent_region->map(address_space().page_directory()))
+                return ENOMEM;
         }
-        new_region.map(address_space().page_directory());
+        if (!new_region.map(address_space().page_directory()))
+            return ENOMEM;
         return 0;
     }
 
@@ -438,9 +440,11 @@ KResultOr<FlatPtr> Process::sys$mprotect(Userspace<void*> addr, size_t size, int
 
             // Map the new region using our page directory (they were just allocated and don't have one) if any.
             if (adjacent_regions.size())
-                adjacent_regions[0]->map(address_space().page_directory());
+                if (!adjacent_regions[0]->map(address_space().page_directory()))
+                    return ENOMEM;
 
-            new_region.map(address_space().page_directory());
+            if (!new_region.map(address_space().page_directory()))
+                return ENOMEM;
         }
 
         return 0;