linux-kernel - Re: [PATCH] soc: brcmstb: Only register SoC device on STB platforms

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 for Android: free password hash cracker in your pocket

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

Date:   Fri, 12 Jan 2018 14:15:08 +0100
From:   Thierry Reding <thierry.reding@...il.com>
To:     Sudeep Holla <sudeep.holla@....com>
Cc:     Brian Norris <computersforpeace@...il.com>,
        Gregory Fong <gregory.0xf0@...il.com>,
        Florian Fainelli <f.fainelli@...il.com>, arm@...nel.org,
        bcm-kernel-feedback-list@...adcom.com,
        linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH] soc: brcmstb: Only register SoC device on STB platforms

On Fri, Jan 12, 2018 at 01:58:28PM +0100, Thierry Reding wrote:
> On Fri, Jan 12, 2018 at 12:12:11PM +0000, Sudeep Holla wrote:
> > 
> > 
> > On 12/01/18 11:39, Sudeep Holla wrote:
> > > 
> > > 
> > > On 09/01/18 14:54, Thierry Reding wrote:
> > >> From: Thierry Reding <treding@...dia.com>
> > >>
> > >> After moving the SoC device initialization to an early initcall in
> > >> commit f780429adfbc ("soc: brcmstb: biuctrl: Move to early_initcall"),
> > >> the Broadcom STB SoC device is registered on all platforms if support
> > >> for the device is enabled in the kernel configuration.
> > >>
> > >> This causes an additional SoC device to appear on platforms that already
> > >> register a native one. In case of Tegra the STB SoC device is registered
> > >> as soc0 (with totally meaningless content in the sysfs attributes) and
> > >> causes various scripts and programs to fail because they don't know how
> > >> to parse that data.
> > >>
> > >> To fix this, duplicate the check from brcmstb_soc_device_early_init()
> > >> that already prevents the code from doing anything nonsensical on non-
> > >> STB platforms.
> > >>
> > >> Fixes: f780429adfbc ("soc: brcmstb: biuctrl: Move to early_initcall")
> > >> Signed-off-by: Thierry Reding <treding@...dia.com>
> > >> ---
> > >>  drivers/soc/bcm/brcmstb/common.c | 5 +++++
> > >>  1 file changed, 5 insertions(+)
> > >>
> > >> diff --git a/drivers/soc/bcm/brcmstb/common.c b/drivers/soc/bcm/brcmstb/common.c
> > >> index 781ada62d0a3..4fe1cb73b39a 100644
> > >> --- a/drivers/soc/bcm/brcmstb/common.c
> > >> +++ b/drivers/soc/bcm/brcmstb/common.c
> > >> @@ -89,8 +89,13 @@ early_initcall(brcmstb_soc_device_early_init);
> > >>  static int __init brcmstb_soc_device_init(void)
> > >>  {
> > >>  	struct soc_device_attribute *soc_dev_attr;
> > >> +	struct device_node *sun_top_ctrl;
> > >>  	struct soc_device *soc_dev;
> > >>  
> > >> +	sun_top_ctrl = of_find_matching_node(NULL, sun_top_ctrl_match);
> > >> +	if (!sun_top_ctrl)
> > >> +		return -ENODEV;
> > >> +
> > > 
> > > missing of_node_put(sun_top_ctrl) ? or am I missing to see that elsewhere ?
> > > 
> > 
> > Further, I still the error messags on my Juno with this patch applied. I
> > fail to see how this patch prevents brcmstb_biuctrl_init which is
> > early_initcall in drivers/soc/bcm/brcmstb/biuctrl.c getting called ?
> 
> I'm not sure I understand. There's no way we can prevent the early
> initcall from running. The point here is to prevent it from running code
> that shouldn't be run on a platform.
> 
> That said, perhaps an even better thing would be to return 0 in order to
> avoid marking this as failure, since it really isn't an error if this
> happens.

Oh, I see the errors you mentioned now. They're in the biuctrl code,
which I hadn't noticed before since they don't cause any weird behaviour
other than the error messages in the boot log. Let me fix that up while
I'm on it.

Thierry

Download attachment "signature.asc" of type "application/pgp-signature" (834 bytes)