net: check before dereferencing netdev_ops during busy poll

net: check before dereferencing netdev_ops during busy poll

[Matteo Croce]

Hi,

Is there any reason for this panic fix not being applied in stable?

https://lore.kernel.org/netdev/20180313053248.13654-1-jelsasser@appneta.com/T/

It seems that linux 4.9.184 has the bug too.

Regards,
-- 
Matteo Croce
per aspera ad upstream

Re: net: check before dereferencing netdev_ops during busy poll

[Sasha Levin]

On Fri, Jun 28, 2019 at 06:34:58PM +0200, Matteo Croce wrote:
>Hi,
>
>Is there any reason for this panic fix not being applied in stable?
>
>https://lore.kernel.org/netdev/20180313053248.13654-1-jelsasser@appneta.com/T/

What's the upstream commit id?

--
Thanks,
Sasha

Re: net: check before dereferencing netdev_ops during busy poll

[Josh Elsasser]

On Jun 28, 2019, at 3:55 PM, Sasha Levin <sashal@kernel.org> wrote:

> What's the upstream commit id?

The commit wasn't needed upstream, as I only sent the original patch after
79e7fff47b7b ("net: remove support for per driver ndo_busy_poll()") had
made the fix unnecessary in Linus' tree.

May've gotten lost in the shuffle due to my poor Fixes tags. The patch in
question applied only on top of the 4.9 stable release at the time, but the
actual NPE had been around in some form since 3.11 / 0602129286705 ("net: add
low latency socket poll").

	Josh

Re: net: check before dereferencing netdev_ops during busy poll

[Greg Kroah-Hartman]

On Fri, Jun 28, 2019 at 07:03:01PM -0700, Josh Elsasser wrote:
> On Jun 28, 2019, at 3:55 PM, Sasha Levin <sashal@kernel.org> wrote:
> 
> > What's the upstream commit id?
> 
> The commit wasn't needed upstream, as I only sent the original patch after
> 79e7fff47b7b ("net: remove support for per driver ndo_busy_poll()") had
> made the fix unnecessary in Linus' tree.
> 
> May've gotten lost in the shuffle due to my poor Fixes tags. The patch in
> question applied only on top of the 4.9 stable release at the time, but the
> actual NPE had been around in some form since 3.11 / 0602129286705 ("net: add
> low latency socket poll").

Ok, can people then resend this and be very explicit as to why this is
needed only in a stable kernel tree and get reviews from people agreeing
that this really is the correct fix?

thanks,

greg k-h

Re: net: check before dereferencing netdev_ops during busy poll

[Matteo Croce]

On Sat, Jun 29, 2019 at 9:45 AM Greg Kroah-Hartman
<gregkh@linuxfoundation.org> wrote:
>
> On Fri, Jun 28, 2019 at 07:03:01PM -0700, Josh Elsasser wrote:
> > On Jun 28, 2019, at 3:55 PM, Sasha Levin <sashal@kernel.org> wrote:
> >
> > > What's the upstream commit id?
> >
> > The commit wasn't needed upstream, as I only sent the original patch after
> > 79e7fff47b7b ("net: remove support for per driver ndo_busy_poll()") had
> > made the fix unnecessary in Linus' tree.
> >
> > May've gotten lost in the shuffle due to my poor Fixes tags. The patch in
> > question applied only on top of the 4.9 stable release at the time, but the
> > actual NPE had been around in some form since 3.11 / 0602129286705 ("net: add
> > low latency socket poll").
>
> Ok, can people then resend this and be very explicit as to why this is
> needed only in a stable kernel tree and get reviews from people agreeing
> that this really is the correct fix?
>
> thanks,
>
> greg k-h

Hi Greg,

I think that David alredy reviewed the patch here:

https://lore.kernel.org/netdev/20180313.105115.682846171057663636.davem@davemloft.net/

Anyway, I tested the patch and it fixes the panic, at least on my
iwlwifi card, so:

Tested-by: Matteo Croce <mcroce@redhat.com>

Regards,
-- 
Matteo Croce
per aspera ad upstream

Re: net: check before dereferencing netdev_ops during busy poll

[Greg Kroah-Hartman]

On Fri, Jun 28, 2019 at 06:34:58PM +0200, Matteo Croce wrote:
> Hi,
> 
> Is there any reason for this panic fix not being applied in stable?
> 
> https://lore.kernel.org/netdev/20180313053248.13654-1-jelsasser@appneta.com/T/

I can't apply patches from random urls :)

Re: net: check before dereferencing netdev_ops during busy poll

[Greg Kroah-Hartman]

On Sat, Jun 29, 2019 at 09:39:39PM +0200, Matteo Croce wrote:
> On Sat, Jun 29, 2019 at 9:45 AM Greg Kroah-Hartman
> <gregkh@linuxfoundation.org> wrote:
> >
> > On Fri, Jun 28, 2019 at 07:03:01PM -0700, Josh Elsasser wrote:
> > > On Jun 28, 2019, at 3:55 PM, Sasha Levin <sashal@kernel.org> wrote:
> > >
> > > > What's the upstream commit id?
> > >
> > > The commit wasn't needed upstream, as I only sent the original patch after
> > > 79e7fff47b7b ("net: remove support for per driver ndo_busy_poll()") had
> > > made the fix unnecessary in Linus' tree.
> > >
> > > May've gotten lost in the shuffle due to my poor Fixes tags. The patch in
> > > question applied only on top of the 4.9 stable release at the time, but the
> > > actual NPE had been around in some form since 3.11 / 0602129286705 ("net: add
> > > low latency socket poll").
> >
> > Ok, can people then resend this and be very explicit as to why this is
> > needed only in a stable kernel tree and get reviews from people agreeing
> > that this really is the correct fix?
> >
> > thanks,
> >
> > greg k-h
> 
> Hi Greg,
> 
> I think that David alredy reviewed the patch here:
> 
> https://lore.kernel.org/netdev/20180313.105115.682846171057663636.davem@davemloft.net/
> 
> Anyway, I tested the patch and it fixes the panic, at least on my
> iwlwifi card, so:
> 
> Tested-by: Matteo Croce <mcroce@redhat.com>

Ok, but what can I do with this?  I need a real patch, in mail form,
that I can apply.  Not a web link to an email archive.

You have read the stable kernel rules, right?  :)

greg k-h

Re: net: check before dereferencing netdev_ops during busy poll

[Matteo Croce]

On Mon, Jul 1, 2019 at 7:53 PM Greg Kroah-Hartman
<gregkh@linuxfoundation.org> wrote:
>
> On Sat, Jun 29, 2019 at 09:39:39PM +0200, Matteo Croce wrote:
> > On Sat, Jun 29, 2019 at 9:45 AM Greg Kroah-Hartman
> > <gregkh@linuxfoundation.org> wrote:
> > >
> > > On Fri, Jun 28, 2019 at 07:03:01PM -0700, Josh Elsasser wrote:
> > > > On Jun 28, 2019, at 3:55 PM, Sasha Levin <sashal@kernel.org> wrote:
> > > >
> > > > > What's the upstream commit id?
> > > >
> > > > The commit wasn't needed upstream, as I only sent the original patch after
> > > > 79e7fff47b7b ("net: remove support for per driver ndo_busy_poll()") had
> > > > made the fix unnecessary in Linus' tree.
> > > >
> > > > May've gotten lost in the shuffle due to my poor Fixes tags. The patch in
> > > > question applied only on top of the 4.9 stable release at the time, but the
> > > > actual NPE had been around in some form since 3.11 / 0602129286705 ("net: add
> > > > low latency socket poll").
> > >
> > > Ok, can people then resend this and be very explicit as to why this is
> > > needed only in a stable kernel tree and get reviews from people agreeing
> > > that this really is the correct fix?
> > >
> > > thanks,
> > >
> > > greg k-h
> >
> > Hi Greg,
> >
> > I think that David alredy reviewed the patch here:
> >
> > https://lore.kernel.org/netdev/20180313.105115.682846171057663636.davem@davemloft.net/
> >
> > Anyway, I tested the patch and it fixes the panic, at least on my
> > iwlwifi card, so:
> >
> > Tested-by: Matteo Croce <mcroce@redhat.com>
>
> Ok, but what can I do with this?  I need a real patch, in mail form,
> that I can apply.  Not a web link to an email archive.
>
> You have read the stable kernel rules, right?  :)
>
> greg k-h

Understood.

Josh, as you are the original author, can you please resend it to -stable?
Feel free to add this tag:

Tested-by: Matteo Croce <mcroce@redhat.com>

Regards,
-- 
Matteo Croce
per aspera ad upstream

Re: net: check before dereferencing netdev_ops during busy poll

[Josh Elsasser]

On Jul 1, 2019, at 11:03 AM, Matteo Croce <mcroce@redhat.com> wrote:

> Josh, as you are the original author, can you please resend it to -stable?
> Feel free to add this tag:
> 
> Tested-by: Matteo Croce <mcroce@redhat.com>

For sure. Resent with your Tested-by, along with a second patch that applies 
to the 4.4.y LTS kernel.

I'm still a little hazy on how net fixes work for older LTS releases, so I
hope I've sent these properly. I can respin if necessary.