diff --git a/kernel/linebuffer.cpp b/kernel/linebuffer.cpp
index c51e0204..2003a314 100644
--- a/kernel/linebuffer.cpp
+++ b/kernel/linebuffer.cpp
@@ -66,9 +66,12 @@ bool LineBuffer::Push(uint32_t unicode)
 		size_t leadingavai = bufferlength-bufferoffset;
 		size_t leading = (leadingavai < bufferused) ? leadingavai : bufferused;
 		size_t trailing = bufferused - leading;
-		memcpy(newbuffer, buffer + bufferoffset, leading * elemsize);
-		memcpy(newbuffer + leading, buffer, trailing * elemsize);
-		delete[] buffer;
+		if ( buffer )
+		{
+			memcpy(newbuffer, buffer + bufferoffset, leading * elemsize);
+			memcpy(newbuffer + leading, buffer, trailing * elemsize);
+			delete[] buffer;
+		}
 		buffer = newbuffer;
 		bufferlength = newbufferlength;
 		bufferoffset = 0;
diff --git a/kernel/ptable.cpp b/kernel/ptable.cpp
index de729405..332e5d62 100644
--- a/kernel/ptable.cpp
+++ b/kernel/ptable.cpp
@@ -72,8 +72,12 @@ pid_t ProcessTable::Allocate(Process* process)
 		struct ptable_entry* new_entries = new struct ptable_entry[new_length];
 		if ( !new_entries )
 			return -1;
-		memcpy(new_entries, entries, sizeof(struct ptable_entry) * entries_length);
-		delete[] entries;
+		if ( entries )
+		{
+			size_t old_size = sizeof(struct ptable_entry) * entries_length;
+			memcpy(new_entries, entries, old_size);
+			delete[] entries;
+		}
 		entries = new_entries;
 		entries_length = new_length;
 	}
diff --git a/kernel/video.cpp b/kernel/video.cpp
index bbafd812..4737f15e 100644
--- a/kernel/video.cpp
+++ b/kernel/video.cpp
@@ -61,8 +61,12 @@ bool RegisterDevice(const char* name, VideoDevice* device)
 		DeviceEntry* newdevices = new DeviceEntry[newdevices_length];
 		if ( !newdevices )
 			return false;
-		memcpy(newdevices, devices, sizeof(*devices) * num_devices);
-		delete[] devices; devices = newdevices;
+		if ( devices )
+		{
+			memcpy(newdevices, devices, sizeof(*devices) * num_devices);
+			delete[] devices;
+		}
+		devices = newdevices;
 		devices_length = devices_length;
 	}