On Tue, 2024-05-28 at 13:02 +0200, Marcin Ślusarz wrote: > > From: Marcin Ślusarz <mslusarz@xxxxxxxxx> > > Right now it's possible to hit NULL pointer dereference in > rtw_rx_fill_rx_status on hw object and/or its fields because > initialization routine can start getting USB replies before > rtw_dev is fully setup. > > The stack trace looks like this: > > rtw_rx_fill_rx_status > rtw8821c_query_rx_desc > rtw_usb_rx_handler > ... > queue_work > rtw_usb_read_port_complete > ... > usb_submit_urb > rtw_usb_rx_resubmit > rtw_usb_init_rx > rtw_usb_probe > > So while we do the async stuff rtw_usb_probe continues and calls > rtw_register_hw, which does all kinds of initialization (e.g. > via ieee80211_register_hw) that rtw_rx_fill_rx_status relies on. > > Fix this by moving the first usb_submit_urb after everything > is set up. > > For me, this bug manifested as: > [ 8.893177] rtw_8821cu 1-1:1.2: band wrong, packet dropped > [ 8.910904] rtw_8821cu 1-1:1.2: hw->conf.chandef.chan NULL in rtw_rx_fill_rx_status > because I'm using Larry's backport of rtw88 driver with the NULL > checks in rtw_rx_fill_rx_status. > > Reported-by: Tim K <tpkuester@xxxxxxxxx> > Closes: > https://lore.kernel.org/linux-wireless/CA+shoWQ7P49jhQasofDcTdQhiuarPTjYEDa--NiVVx494WcuQw@xxxxxxxxxxxxxx/ Change Closes to Link during committing because of no ACK from Tim. > Signed-off-by: Marcin Ślusarz <mslusarz@xxxxxxxxx> > Cc: Ping-Ke Shih <pkshih@xxxxxxxxxxx> > Cc: Larry Finger <Larry.Finger@xxxxxxxxxxxx> > Cc: Kalle Valo <kvalo@xxxxxxxxxx> > Cc: linux-wireless@xxxxxxxxxxxxxxx > Cc: linux-kernel@xxxxxxxxxxxxxxx > 1 patch(es) applied to rtw-next branch of rtw.git, thanks. adc539784c98 wifi: rtw88: usb: schedule rx work after everything is set up --- https://github.com/pkshih/rtw.git
