[alsa-devel] [PATCH] ALSA: usb-audio: Fix gpf in snd_usb_pipe_sanity_check

[Hillf Danton]

On Tue, 30 Jul 2019 18:08:02 +0800 Takashi Iwai wrote:
>
> You don't have to copy the whole these texts at all.
> In general, it'd suffice to point out the dashboard URL, and if the
> stack trace is mandatory, drop the useless hex numbers and just show
> the significant part of the stack trace.
>
I am used to give readers as much info as appropriate, and learning that
an URL is enough in cases like this one. I will send you the pruned
version next time.

> > It was introduced in commit 801ebf1043ae for checking pipe and endpoint
> > types. It is fixed by adding a check of the ep pointer in question.
> >
> > Reported-by: syzbot <syzbot+d59c4387bfb6eced94e2 at syzkaller.appspotmail.com>
> > Fixes: commit 801ebf1043ae ("ALSA: usb-audio: Sanity checks for each pipe and EP types")
>
> Drop "commit" word.
>
Yes, Sir.

> > Cc: Andrey Konovalov <andreyknvl at google.com>
> > Signed-off-by: Hillf Danton <dhanton at sina.com>
> > ---
There is a typo, s/dhanton/hdanton/, as you pointed out in another mail.

> > This is to make syzbot happy for now and in long run we can make
> > snd_usb_pipe_sanity_check() available outside sound/usb by making
> > usb_urb_ep_type_check() a wrapper of the former. We will revisit
> > sound/usb once when things in the usb/core get in place.
>
> Actually I expected to apply the "long-term" fix now.

There is change in usb/core included in that fix as you see, and
according to the rule, one fix a patch, it is better and simpler
IMO to fix the sound part first.

> The same kind
> of fix was already submitted from me (<s5hlfwn376e.wl-tiwai at suse.de>),
> but I didn't merge it because working on the usb core helper would be
> a saner solution.
>
Feel free to merge that, Sir.

Thanks
Hillf