Re: [PATCH] wifi: cfg80211: Lock wiphy in cfg80211_get_station

[Antonio Quartulli]

Hi,

On 18/05/2024 17:50, Remi Pommarel wrote:
> Wiphy should be locked before calling rdev_get_station() (see lockdep
> assert in ieee80211_get_station()).

Adding the lock is fine as nowadays it is taken in pre_doit and released 
in post_doit (with some exceptions). Therefore when invoking 
get_station from a side path the lock should be taken too.

It was actually a05829a7222e9d10c416dd2dbbf3929fe6646b89 that introduced 
this requirement AFAICS.

> This fixes the following kernel NULL dereference:

As already said by Johannes, I am not sure it truly fixes this NULL 
dereference though.

Have you checked where in ath10k_sta_statistics this is exactly 
happening? Do you think some sta was partly released and thus fields 
were NULLified?

Regards,


--
Antonio Quartulli