In the Linux kernel, the following vulnerability has been resolved: hwrng: core - fix rng list...

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

hwrng: core - fix rng list on registration error

hwrng_register(rng) does the following:

1. Checks if rng has name and read methods set
2. Checks if the name already exists
3. Adds rng to global rng_list
4. May try to set rng to current_rng

If step 4 fails, it returns an error. However, it does not remove the rng from rng_list, causing a dangling reference which can result in use-after-free if the caller frees rng, since registration failed.

Add a list_del_init() cleanup step.