diff --git a/src/util/vfs/vfs-mem.c b/src/util/vfs/vfs-mem.c
index 05d5a599f..06189b886 100644
--- a/src/util/vfs/vfs-mem.c
+++ b/src/util/vfs/vfs-mem.c
@@ -226,9 +226,10 @@ ssize_t _vfmRead(struct VFile* vf, void* buffer, size_t size) {
 	if (size + vfm->offset >= vfm->size) {
 		size = vfm->size - vfm->offset;
 	}
-
-	memcpy(buffer, (void*) ((uintptr_t) vfm->mem + vfm->offset), size);
-	vfm->offset += size;
+	if (size) {
+		memcpy(buffer, (void*) ((uintptr_t) vfm->mem + vfm->offset), size);
+		vfm->offset += size;
+	}
 	return size;
 }