Re: [PATCH RFC v2 0/6] staging: r8188eu: avoid uninit value bugs

Fabio M. De Francesco
2021-08-22T20:06:30Z

On Sunday, August 22, 2021 7:38:11 PM CEST Pavel Skripkin wrote:
> On 8/22/21 8:36 PM, Fabio M. De Francesco wrote:
> > On Sunday, August 22, 2021 4:35:05 PM CEST Pavel Skripkin wrote:
> >> Hi, Greg, Larry and Phillip!
> >>
> >> I noticed, that new staging driver was added like 3 weeks ago and I decided
> >> to look at the code, because drivers in staging directory are always buggy.
> >>
> >> The first thing I noticed is *no one* was checking read operations result, but
> >> it can fail and driver may start writing random stack values into registers. It
> >> can cause driver misbehavior or device misbehavior.
> >>
> >> To avoid this type of bugs, I've changed rtw_read* API. Now all rtw_read
> >> funtions return an error, when something went wrong with usb transfer.
> >>
> >> It helps callers to break/return earlier and don't write random values to
> >> registers or to rely on random values.
> >>
> >> Why is this pacth series RFC?
> >> 1. I don't have this device and I cannot test these changes.
> >> 2. I don't know how to handle errors in each particular case. For now, function
> >> just returns or returns an error. That's all. I hope, driver maintainers will
> >> help with these bits.
> >> 3. I guess, I handled not all uninit value bugs here. I hope, I fixed
> >> at least half of them
> >>
> >> v1 -> v2:
> >> 1. Make rtw_read*() return an error instead of initializing pointer to error
> >> 2. Split one huge patch to smaller ones for each rtw_read{8,16,32} function
> >> changes
> >> 3. Add new macro for printing register values (It helps to not copy-paste error
> >> handling)
> >> 4. Removed {read,write}_macreg (Suggested by Phillip)
> >> 5. Rebased on top of staging-next
> >> 6. Cleaned checkpatch errors and warnings
> >>
> >> Only build-tested, since I don't have device with r8118eu chip
> >>
> >> Pavel Skripkin (6):
> >> staging: r8188eu: remove {read,write}_macreg
> >> staging: r8188eu: add helper macro for printing registers
> >> staging: r8188eu: add error handling of rtw_read8
> >> staging: r8188eu: add error handling of rtw_read16
> >> staging: r8188eu: add error handling of rtw_read32
> >> staging: r8188eu: make ReadEFuse return an int
> >
> > Hi Pavel,
> >
> > I've just read your v2 of the series. I had no time to read each and every line,
> > however, I suppose that I saw enough to say that I think they are a huge
> > improvement over v1. I really like your patches and if I were you, I'd drop
> > that RFC tag.
> >
>
> Thank you, Fabio! I appreciate it :)
>
>
> With regards,
> Pavel Skripkin

Hi Pavel,

I've read more code of your series and I'm ready to give a formal ack. However,
I'm not sure about the rules: can it be also given to RFC or only to "real" patches?

As I've already said, they look good and I like them. So, the entire series is...

Acked-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>

If the rules don't allow to formally ack RFC, I will be happy to ack again the final product.

I also want to say that I enjoyed discussing this work with you on this long thread. :-)

Thanks,

Fabio