Re: [PATCH RFC 0/3] staging: r8188eu: avoid uninit value bugs

From: Pavel Skripkin
Date: Sun Aug 22 2021 - 09:31:39 EST


On 8/22/21 4:21 PM, Fabio M. De Francesco wrote:
On Sunday, August 22, 2021 2:39:34 PM CEST Greg KH wrote:
On Sun, Aug 22, 2021 at 03:10:56PM +0300, Pavel Skripkin wrote:
> On 8/22/21 1:59 PM, Fabio M. De Francesco wrote:
> > On Sunday, August 22, 2021 12:09:29 PM CEST Pavel Skripkin wrote:
[...]
> > So, it's up to the callers to test if (!_rtw_read*()) and then act
> > accordingly. If they get 0 they should know how to handle the errors.
> > Yes, but _rtw_read*() == 0 indicates 2 states:
> 1. Error on transfer side
> 2. Actual register value is 0

That's not a good design, it should be fixed. Note there is the new
usb_control_msg_recv() function which should probably be used instead
here, to prevent this problem from happening.

I think that no functions should return 0 for signaling FAILURE. If I'm not
wrong, the kernel quite always prefers to return 0 on SUCCESS and <0 on
FAILURE. Why don't you just fix this?


That's what I've done in v2. All rtw_read* family will have following prototype in v2:

int __must_check _rtw_read8(struct adapter *adapter, u32 addr, u8 *data);


Was it your idea, or you were talking about different approach?


With regards,
Pavel Skripkin