2019-06-28 16:36:04

by Matteo Croce

[permalink] [raw]
Subject: net: check before dereferencing netdev_ops during busy poll

Hi,

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

https://lore.kernel.org/netdev/[email protected]/T/

It seems that linux 4.9.184 has the bug too.

Regards,
--
Matteo Croce
per aspera ad upstream


2019-06-28 22:56:08

by Sasha Levin

[permalink] [raw]
Subject: Re: net: check before dereferencing netdev_ops during busy poll

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/[email protected]/T/

What's the upstream commit id?

--
Thanks,
Sasha

2019-06-29 02:04:15

by Josh Elsasser

[permalink] [raw]
Subject: Re: net: check before dereferencing netdev_ops during busy poll

On Jun 28, 2019, at 3:55 PM, Sasha Levin <[email protected]> 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

2019-06-29 07:46:19

by Greg Kroah-Hartman

[permalink] [raw]
Subject: Re: net: check before dereferencing netdev_ops during busy poll

On Fri, Jun 28, 2019 at 07:03:01PM -0700, Josh Elsasser wrote:
> On Jun 28, 2019, at 3:55 PM, Sasha Levin <[email protected]> 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

2019-06-29 19:40:40

by Matteo Croce

[permalink] [raw]
Subject: Re: net: check before dereferencing netdev_ops during busy poll

On Sat, Jun 29, 2019 at 9:45 AM Greg Kroah-Hartman
<[email protected]> wrote:
>
> On Fri, Jun 28, 2019 at 07:03:01PM -0700, Josh Elsasser wrote:
> > On Jun 28, 2019, at 3:55 PM, Sasha Levin <[email protected]> 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/[email protected]/

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

Tested-by: Matteo Croce <[email protected]>

Regards,
--
Matteo Croce
per aspera ad upstream

2019-07-01 18:21:15

by Greg Kroah-Hartman

[permalink] [raw]
Subject: Re: net: check before dereferencing netdev_ops during busy poll

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/[email protected]/T/

I can't apply patches from random urls :)

2019-07-01 18:21:26

by Greg Kroah-Hartman

[permalink] [raw]
Subject: Re: net: check before dereferencing netdev_ops during busy poll

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
> <[email protected]> wrote:
> >
> > On Fri, Jun 28, 2019 at 07:03:01PM -0700, Josh Elsasser wrote:
> > > On Jun 28, 2019, at 3:55 PM, Sasha Levin <[email protected]> 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/[email protected]/
>
> Anyway, I tested the patch and it fixes the panic, at least on my
> iwlwifi card, so:
>
> Tested-by: Matteo Croce <[email protected]>

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

2019-07-01 18:22:41

by Matteo Croce

[permalink] [raw]
Subject: Re: net: check before dereferencing netdev_ops during busy poll

On Mon, Jul 1, 2019 at 7:53 PM Greg Kroah-Hartman
<[email protected]> 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
> > <[email protected]> wrote:
> > >
> > > On Fri, Jun 28, 2019 at 07:03:01PM -0700, Josh Elsasser wrote:
> > > > On Jun 28, 2019, at 3:55 PM, Sasha Levin <[email protected]> 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/[email protected]/
> >
> > Anyway, I tested the patch and it fixes the panic, at least on my
> > iwlwifi card, so:
> >
> > Tested-by: Matteo Croce <[email protected]>
>
> 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 <[email protected]>

Regards,
--
Matteo Croce
per aspera ad upstream

2019-07-01 23:53:07

by Josh Elsasser

[permalink] [raw]
Subject: Re: net: check before dereferencing netdev_ops during busy poll

On Jul 1, 2019, at 11:03 AM, Matteo Croce <[email protected]> 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 <[email protected]>

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.