[PATCH 4.9 012/191] usblp: poison URBs upon disconnect

Sasha Levin
2020-06-29T20:25:19Z

From: Oliver Neukum <oneukum@suse.com>

[ Upstream commit 296a193b06120aa6ae7cf5c0d7b5e5b55968026e ]

syzkaller reported an URB that should have been killed to be active.
We do not understand it, but this should fix the issue if it is real.

Signed-off-by: Oliver Neukum <oneukum@suse.com>
Reported-by: syzbot+be5b5f86a162a6c281e6@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/20200507085806.5793-1-oneukum@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/usb/class/usblp.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/class/usblp.c b/drivers/usb/class/usblp.c
index 07c3c3449147f..c578d64edc153 100644
--- a/drivers/usb/class/usblp.c
+++ b/drivers/usb/class/usblp.c
@@ -481,7 +481,8 @@ static int usblp_release(struct inode *inode, struct file *file)
usb_autopm_put_interface(usblp->intf);

if (!usblp->present) /* finish cleanup from disconnect */
- usblp_cleanup(usblp);
+ usblp_cleanup(usblp); /* any URBs must be dead */
+
mutex_unlock(&usblp_mutex);
return 0;
}
@@ -1397,9 +1398,11 @@ static void usblp_disconnect(struct usb_interface *intf)

usblp_unlink_urbs(usblp);
mutex_unlock(&usblp->mut);
+ usb_poison_anchored_urbs(&usblp->urbs);

if (!usblp->used)
usblp_cleanup(usblp);
+
mutex_unlock(&usblp_mutex);
}

--
2.25.1