Hi,
On 04/04/2017 08:31 PM, Larry Finger wrote:
On 03/29/2017 12:47 PM, Hans de Goede wrote:
The rtl8723bs is found on quite a few systems used by Linux users,
such as on Atom systems (Intel Computestick and various other
Atom based devices) and on many (budget) ARM boards such as
the CHIP.
The plan moving forward with this is for the new clean,
written from scratch, rtl8xxxu driver to eventually gain
support for sdio devices. But there is no clear timeline
for that, so lets add this driver included in staging for now.
Hans,
I started looking at the Smatch errors. This one may be the result of a serious
problem:
CHECK drivers/staging/rtl8723bs/core/rtw_debug.c
drivers/staging/rtl8723bs/core/rtw_debug.c:454 proc_get_survey_info() error: we
previously assumed 'phead' could be null (see line 453)
drivers/staging/rtl8723bs/core/rtw_debug.c:455 proc_get_survey_info() warn:
variable dereferenced before check 'phead' (see line 454)
A snippet of the code in question is as follows:
spin_lock_bh(&(pmlmepriv->scanned_queue.lock));
phead = get_list_head(queue);
plist = phead ? get_next(phead) : NULL;
plist = get_next(phead);
if ((!phead) || (!plist)) {
spin_unlock_bh(&(pmlmepriv->scanned_queue.lock));
return 0;
}
This code comes directly from the hadess repo, but I am suspicious of the
double call to get_next(phead). I cannot imagine any valid reason to skip every
other entry on that list.
If you look closer and simplify the first getnext line what is written is:
plist = get_next(phead);
plist = get_next(phead);
Which indeed looks like it could use improvement, but I don't
think it is seriously broken.
Regards,
Hans
