void* ipc_rcu_alloc(int size)
void *ipc_rcu_alloc(int size)
 {
	void *out;

	/*
 	 * We prepend the allocation with the rcu struct, and
	 * workqueue if necessary (for vmalloc).
 	 */
 	if (rcu_use_vmalloc(size)) {
 		out = vmalloc(HDRLEN_VMALLOC + size);
		if (!out)
			goto done;

		out += HDRLEN_VMALLOC;
		container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1;
 	} else {
 		out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL);
		if (!out)
			goto done;

		out += HDRLEN_KMALLOC;
		container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0;
 	}
 
	/* set reference counter no matter what kind of allocation was done */
	atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1);
done:
 	return out;
 }

This weakness involves numeric computation errors, such as integer overflows, underflows, or precision losses, which can lead to miscalculations and exploitable behaviors in software.