int oz_cdev_start(struct oz_pd *pd, int resume)
{
	struct oz_serial_ctx *ctx;
	struct oz_serial_ctx *old_ctx;

	if (resume) {
		oz_dbg(ON, "Serial service resumed\n");
		return 0;
	}
	ctx = kzalloc(sizeof(struct oz_serial_ctx), GFP_ATOMIC);
	if (ctx == NULL)
		return -ENOMEM;
	atomic_set(&ctx->ref_count, 1);
	ctx->tx_seq_num = 1;
	spin_lock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]);
	old_ctx = pd->app_ctx[OZ_APPID_SERIAL-1];
	if (old_ctx) {
		spin_unlock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]);
		kfree(ctx);
	} else {
		pd->app_ctx[OZ_APPID_SERIAL-1] = ctx;
		spin_unlock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]);
	}
	spin_lock(&g_cdev.lock);
	if ((g_cdev.active_pd == NULL) &&
		(memcmp(pd->mac_addr, g_cdev.active_addr, ETH_ALEN) == 0)) {
		oz_pd_get(pd);
		g_cdev.active_pd = pd;
		oz_dbg(ON, "Active PD arrived\n");
	}
	spin_unlock(&g_cdev.lock);
	oz_dbg(ON, "Serial service started\n");
	return 0;
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.