Re: ath9k broken [was: Linux 5.7.3]

[Gabriel C <nix.or.die@googlemail.com>]

Am Fr., 26. Juni 2020 um 15:51 Uhr schrieb Gabriel C
<nix.or.die@googlemail.com>:
>
> Am Fr., 26. Juni 2020 um 15:40 Uhr schrieb Greg Kroah-Hartman
> <gregkh@linuxfoundation.org>:
> >
> > On Fri, Jun 26, 2020 at 01:48:59PM +0200, Gabriel C wrote:
> > > Am Do., 25. Juni 2020 um 12:52 Uhr schrieb Gabriel C
> > > <nix.or.die@googlemail.com>:
> > > >
> > > > Am Do., 25. Juni 2020 um 12:48 Uhr schrieb Gabriel C
> > > > <nix.or.die@googlemail.com>:
> > > > >
> > > > > Am Do., 25. Juni 2020 um 06:57 Uhr schrieb Jiri Slaby <jirislaby@kernel.org>:
> > > > > >
> > > > > > On 25. 06. 20, 0:05, Gabriel C wrote:
> > > > > > > Am Mi., 17. Juni 2020 um 18:13 Uhr schrieb Greg Kroah-Hartman
> > > > > > > <gregkh@linuxfoundation.org>:
> > > > > > >>
> > > > > > >> I'm announcing the release of the 5.7.3 kernel.
> > > > > > >>
> > > > > > >
> > > > > > > Hello Greg,
> > > > > > >
> > > > > > >> Qiujun Huang (5):
> > > > > > >>       ath9k: Fix use-after-free Read in htc_connect_service
> > > > > > >>       ath9k: Fix use-after-free Read in ath9k_wmi_ctrl_rx
> > > > > > >>       ath9k: Fix use-after-free Write in ath9k_htc_rx_msg
> > > > > > >>       ath9x: Fix stack-out-of-bounds Write in ath9k_hif_usb_rx_cb
> > > > > > >>       ath9k: Fix general protection fault in ath9k_hif_usb_rx_cb
> > > > > > >>
> > > > > > >
> > > > > > > We got a report on IRC about 5.7.3+ breaking a USB ath9k Wifi Dongle,
> > > > > > > while working fine on <5.7.3.
> > > > > > >
> > > > > > > I don't have myself such HW, and the reported doesn't have any experience
> > > > > > > in bisecting the kernel, so we build kernels, each with one of the
> > > > > > > above commits reverted,
> > > > > > > to find the bad commit.
> > > > > > >
> > > > > > > The winner is:
> > > > > > >
> > > > > > > commit 6602f080cb28745259e2fab1a4cf55eeb5894f93
> > > > > > > Author: Qiujun Huang <hqjagain@gmail.com>
> > > > > > > Date:   Sat Apr 4 12:18:38 2020 +0800
> > > > > > >
> > > > > > >     ath9k: Fix general protection fault in ath9k_hif_usb_rx_cb
> > > > > > >
> > > > > > >     commit 2bbcaaee1fcbd83272e29f31e2bb7e70d8c49e05 upstream.
> > > > > > > ...
> > > > > > >
> > > > > > > Reverting this one fixed his problem.
> > > > > >
> > > > > > Obvious question: is 5.8-rc1 (containing the commit) broken too?
> > > > >
> > > > > Yes, it does, just checked.
> > > > >
> > > > > git tag --contains 2bbcaaee1fcbd83272e29f31e2bb7e70d8c49e05
> > > > > v5.8-rc1
> > > > > v5.8-rc2
> > > > >
> > > >
> > > > Sorry, I read the wrong, I just woke up.
> > > >
> > > > We didn't test 5.8-rc{1,2} yet but we will today and let you know.
> > > >
> > >
> > > We tested 5.8-rc2 and it is broken too.
> > >
> > > The exact HW name is:
> > >
> > > TP-link tl-wn722n (Atheros AR9271 chip)
> >
> > Great!
> >
> > Can you work with the developers to fix this in Linus's tree first?
>
> I'm the man in the middle, but sure we will try patches or any suggestions
> from developers to identify and fix the problem.
>
> >
> > I bet they want to see the output of 'lsusb -v' for this device to see
> > if the endpoint calculations are correct...
> >
>
> Working on it. As soon the reporter gives me the output, I will post it here.
> I've told him to run it on a broken and one working kernel.

That is from a good kernel with reverted commit
https://gist.github.com/AngryPenguinPL/07c8e2abd3b103eaf8978a39ad8577d1

That is from the broken kernel without the commit reverted
https://gist.github.com/AngryPenguinPL/5cdc0dd16ce5e59ff3c32c048e2f5111

This is from 5.7.5 kernel, I don't have yet a 5.8-rc2 package with the
reverted commit.