Re: [PATCH] staging: r8188eu: fix NULL check for rcu pointer

[Martin Kaiser]

Hello Greg and all,

Thus wrote Greg Kroah-Hartman (gregkh@xxxxxxxxxxxxxxxxxxx):

> On Tue, Jan 31, 2023 at 10:00:57AM +0100, Martin Kaiser wrote:
> > Fix the NULL check for padapter->pnetdev->rx_handler_data.

> > The current code calls rcu_dereference while it holds the rcu read lock
> > and checks the pointer after releasing the lock. An rcu pointer may only be
> > used between calls to rcu_read_lock and rcu_read_unlock.

> > Replace the check with rcu_access_pointer. My understanding is that this
> > function returns the value of the pointer and needs no locking. We can
> > then check the pointer but we must not dereference it.

> > Signed-off-by: Martin Kaiser <martin@xxxxxxxxx>

> What commit id does this fix?

the code that checks br_port has been around since the driver was
imported into staging.

If the patch is considered as a fix, it should have

Fixes: 15865124feed ("staging: r8188eu: introduce new core dir for RTL8188eu driver")

Best regards,

   Martin