linux-kernel - Re: [PATCH] USB / dwc3: remove the use of -ENOSYS from core.c

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <HK0PR01MB2801E9A6A53F346BC3436845F8D39@HK0PR01MB2801.apcprd01.prod.exchangelabs.com>
Date:   Fri, 20 May 2022 12:16:29 +0530
From:   Kushagra Verma <kushagra765@...look.com>
To:     Greg KH <gregkh@...uxfoundation.org>
Cc:     balbi@...nel.org, linux-usb@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] USB / dwc3: remove the use of -ENOSYS from core.c

On Thu, 2022-05-19 at 17:59 +0200, Greg KH wrote:
> On Tue, May 17, 2022 at 08:22:00PM +0530, Kushagra Verma wrote:
> > This patch removes the use of -ENOSYS as it is used when users try
> > to call a
> > syscall that doesn't exist. So, we don't need to check if 'ret == -
> > ENOSYS'.
> 
> ENOSYS is also used internally in the kernel for other things.
> 
> > 
> > Signed-off-by: Kushagra Verma <kushagra765@...look.com>
> > ---
> >  drivers/usb/dwc3/core.c | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> > index c78205c5e19f..3c1a877d5183 100644
> > --- a/drivers/usb/dwc3/core.c
> > +++ b/drivers/usb/dwc3/core.c
> > @@ -1283,7 +1283,7 @@ static int dwc3_core_get_phy(struct dwc3
> > *dwc)
> >         dwc->usb2_generic_phy = devm_phy_get(dev, "usb2-phy");
> >         if (IS_ERR(dwc->usb2_generic_phy)) {
> >                 ret = PTR_ERR(dwc->usb2_generic_phy);
> > -               if (ret == -ENOSYS || ret == -ENODEV)
> > +               if (ret == -ENODEV)
> 
> Did you validate that no callers can ever set this to ENOSYS?
Yes, I think no callers should ever set ret to ENOSYS unless it comes under the other things ENOSYS is used for.
> 
> Why was this added in the first place?  What commit added it?
This was added by commit 57303488cd37d ("usb: dwc3: adapt dwc3 core to use Generic PHY Framework").
> 
> thanks,
> 
> greg k-h

Thanks,

Kushagra