Re: [PATCH] class: fix use-after-free in class_register()

[Greg Kroah-Hartman]

On Mon, Dec 18, 2023 at 10:44:03AM +0800, Chunyan Zhang wrote:
> From: Jing Xia <jing.xia@xxxxxxxxxx>
> 
> The lock_class_key is still registered and can be found in
> lock_keys_hash hlist after subsys_private is freed in error
> handler path.A task who iterate over the lock_keys_hash
> later may cause use-after-free.So fix that up and unregister
> the lock_class_key before kfree(cp).

What task iterates over all hashes?

And can you put ' ' after your '.'?

And how was this found?

> 
> Signed-off-by: Jing Xia <jing.xia@xxxxxxxxxx>
> Signed-off-by: Xuewen Yan <xuewen.yan@xxxxxxxxxx>

What commit id does this fix?

Also note in the changelog that this only can happen if lockdep is
enabled, which is not true for normal systems.

thanks,

greg k-h