CVE-2023-52510

In the Linux kernel, the following vulnerability has been resolved:

ieee802154: ca8210: Fix a potential UAF in ca8210_probe

If ofclkaddprovider() fails in ca8210registerextclock(), it calls clkunregister() to release priv->clk and returns an error. However, the caller ca8210probe() then calls ca8210remove(), where priv->clk is freed again in ca8210unregisterextclock(). In this case, a use-after-free may happen in the second time we call clk_unregister().

Fix this by removing the first clkunregister(). Also, priv->clk could be an error code on failure of clkregisterfixedrate(). Use ISERRORNULL to catch this case in ca8210unregisterextclock().