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: <3894dd38-377b-4691-907b-ec3d47fddffd@kadam.mountain>
Date:   Fri, 23 Jun 2023 14:44:01 +0300
From:   Dan Carpenter <dan.carpenter@...aro.org>
To:     Sai Krishna Gajula <saikrishnag@...vell.com>
Cc:     "davem@...emloft.net" <davem@...emloft.net>,
        "edumazet@...gle.com" <edumazet@...gle.com>,
        "kuba@...nel.org" <kuba@...nel.org>,
        "pabeni@...hat.com" <pabeni@...hat.com>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        Sunil Kovvuri Goutham <sgoutham@...vell.com>,
        "maciej.fijalkowski@...el.com" <maciej.fijalkowski@...el.com>,
        Naveen Mamindlapalli <naveenm@...vell.com>
Subject: Re: [net PATCH v2] octeontx2-af: Move validation of ptp pointer
 before its usage

On Fri, Jun 23, 2023 at 11:28:19AM +0000, Sai Krishna Gajula wrote:
> > This probe function is super weird how it returns success on the failure path.
> > One concern, I had initially was that if anything returns -EPROBE_DEFER then
> > we cannot recover.  That's not possible in the current code, but it makes me
> > itch...  But here is a different crash.
> > 
> 
> In few circumstances, the PTP device is probed before the AF device in
> the driver. In such instance, -EPROBE_DEFER is used.
> -- EDEFER_PROBE is useful when probe order changes. Ex: AF driver probes before PTP.
> 

You're describing how -EPROBE_DEFER is *supposed* to work.  But that's
not what this driver does.

If the AF driver is probed before the PTP driver then ptp_probe() should
return -EPROBE_DEFER and that would allow the kernel to automatically
retry ptp_probe() later.  But instead of that, ptp_probe() returns
success.  So I guess the user would have to manually rmmod it and insmod
it again?  So, what I'm saying I don't understand why we can't do this
in the normal way.

The other thing I'm saying is that the weird return success on error
stuff hasn't been tested or we would have discovered the crash through
testing.

regards,
dan carpenter

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ