Re: WARNING in _chaoskey_fill/usb_submit_urb

From: Oliver Neukum
Date: Mon Sep 30 2019 - 09:50:45 EST


Am Montag, den 23.09.2019, 07:31 -0700 schrieb syzbot:
> Hello,
>
> syzbot found the following crash on:
>
> HEAD commit: e0bd8d79 usb-fuzzer: main usb gadget fuzzer driver
> git tree: https://github.com/google/kasan.git usb-fuzzer
> console output: https://syzkaller.appspot.com/x/log.txt?x=1452c6a1600000
> kernel config: https://syzkaller.appspot.com/x/.config?x=8847e5384a16f66a
> dashboard link: https://syzkaller.appspot.com/bug?extid=f5349b421c6213d34ce2
> compiler: gcc (GCC) 9.0.0 20181231 (experimental)
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16342d45600000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=166769b1600000
>
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+f5349b421c6213d34ce2@xxxxxxxxxxxxxxxxxxxxxxxxx

#syz test: https://github.com/google/kasan.git e0bd8d79From 27b0085768b55f2ed8faf4f1254023a03dc3eb24 Mon Sep 17 00:00:00 2001
From: Oliver Neukum <oneukum@xxxxxxxx>
Date: Mon, 30 Sep 2019 15:19:13 +0200
Subject: [PATCH] USB: chaoskey: fix error case of a timeout

In case of a timeout communication with the device needs to be ended
from the host side, lest we overwrite an active URB

Signed-off-by: Oliver Neukum <oneukum@xxxxxxx>
---
drivers/usb/misc/chaoskey.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/usb/misc/chaoskey.c b/drivers/usb/misc/chaoskey.c
index cf5828ce927a..850f46cbace2 100644
--- a/drivers/usb/misc/chaoskey.c
+++ b/drivers/usb/misc/chaoskey.c
@@ -391,6 +391,8 @@ static int _chaoskey_fill(struct chaoskey *dev)
else
result = dev->valid;
out:
+ /* in case of a timeout */
+ usb_kill_urb(dev->urb);
/* Let the device go back to sleep eventually */
usb_autopm_put_interface(dev->interface);

--
2.16.4