Patch "ALSA: usb-audio: Fix gpf in snd_usb_pipe_sanity_check" has been added to the 4.19-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    ALSA: usb-audio: Fix gpf in snd_usb_pipe_sanity_check

to the 4.19-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     alsa-usb-audio-fix-gpf-in-snd_usb_pipe_sanity_check.patch
and it can be found in the queue-4.19 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From stable+bounces-73597-greg=kroah.com@vger.kernel.org Thu Sep  5 14:38:24 2024
From: Hillf Danton <dan.carpenter@linaro.org>
Date: Thu, 5 Sep 2024 15:38:13 +0300
Subject: ALSA: usb-audio: Fix gpf in snd_usb_pipe_sanity_check
To: Takashi Iwai <tiwai@suse.de>
Cc: Jaroslav Kysela <perex@perex.cz>, Takashi Iwai <tiwai@suse.com>, Hillf Danton <hdanton@sina.com>, alsa-devel@alsa-project.org, stable@vger.kernel.org
Message-ID: <d830ede4-1736-4548-94b3-51a21fa935c3@stanley.mountain>
Content-Disposition: inline

From: Hillf Danton <dan.carpenter@linaro.org>

[ Upstream commit 5d78e1c2b7f4be00bbe62141603a631dc7812f35 ]

syzbot found the following crash on:

  general protection fault: 0000 [#1] SMP KASAN
  RIP: 0010:snd_usb_pipe_sanity_check+0x80/0x130 sound/usb/helper.c:75
  Call Trace:
    snd_usb_motu_microbookii_communicate.constprop.0+0xa0/0x2fb  sound/usb/quirks.c:1007
    snd_usb_motu_microbookii_boot_quirk sound/usb/quirks.c:1051 [inline]
    snd_usb_apply_boot_quirk.cold+0x163/0x370 sound/usb/quirks.c:1280
    usb_audio_probe+0x2ec/0x2010 sound/usb/card.c:576
    usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:361
    really_probe+0x281/0x650 drivers/base/dd.c:548
    ....

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.

BugLink: https://syzkaller.appspot.com/bug?extid=d59c4387bfb6eced94e2
Reported-by: syzbot <syzbot+d59c4387bfb6eced94e2@syzkaller.appspotmail.com>
Fixes: 801ebf1043ae ("ALSA: usb-audio: Sanity checks for each pipe and EP types")
Cc: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Hillf Danton <hdanton@sina.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 sound/usb/helper.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/sound/usb/helper.c
+++ b/sound/usb/helper.c
@@ -85,7 +85,7 @@ int snd_usb_pipe_sanity_check(struct usb
 	struct usb_host_endpoint *ep;
 
 	ep = usb_pipe_endpoint(dev, pipe);
-	if (usb_pipetype(pipe) != pipetypes[usb_endpoint_type(&ep->desc)])
+	if (!ep || usb_pipetype(pipe) != pipetypes[usb_endpoint_type(&ep->desc)])
 		return -EINVAL;
 	return 0;
 }


Patches currently in stable-queue which might be from dan.carpenter@linaro.org are

queue-4.19/alsa-usb-audio-sanity-checks-for-each-pipe-and-ep-types.patch
queue-4.19/alsa-usb-audio-fix-gpf-in-snd_usb_pipe_sanity_check.patch