* [PATCH 1/6] USB: iowarrior: fix use-after-free on disconnect
[not found] <20191009104846.5925-1-johan@kernel.org>
@ 2019-10-09 10:48 ` Johan Hovold
2019-10-09 10:48 ` [PATCH 2/6] USB: iowarrior: fix use-after-free on release Johan Hovold
2019-10-09 10:48 ` [PATCH 3/6] USB: iowarrior: fix use-after-free after driver unbind Johan Hovold
2 siblings, 0 replies; 3+ messages in thread
From: Johan Hovold @ 2019-10-09 10:48 UTC (permalink / raw)
To: Greg Kroah-Hartman
Cc: Oliver Neukum, Valentin Vidic, linux-usb, linux-kernel,
Johan Hovold, stable, syzbot+0761012cebf7bdb38137
A recent fix addressing a deadlock on disconnect introduced a new bug
by moving the present flag out of the critical section protected by the
driver-data mutex. This could lead to a racing release() freeing the
driver data before disconnect() is done with it.
Due to insufficient locking a related use-after-free could be triggered
also before the above mentioned commit. Specifically, the driver needs
to hold the driver-data mutex also while checking the opened flag at
disconnect().
Fixes: c468a8aa790e ("usb: iowarrior: fix deadlock on disconnect")
Fixes: 946b960d13c1 ("USB: add driver for iowarrior devices.")
Cc: stable <stable@vger.kernel.org> # 2.6.21
Reported-by: syzbot+0761012cebf7bdb38137@syzkaller.appspotmail.com
Signed-off-by: Johan Hovold <johan@kernel.org>
---
drivers/usb/misc/iowarrior.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/usb/misc/iowarrior.c b/drivers/usb/misc/iowarrior.c
index f5bed9f29e56..4fe1d3267b3c 100644
--- a/drivers/usb/misc/iowarrior.c
+++ b/drivers/usb/misc/iowarrior.c
@@ -866,8 +866,6 @@ static void iowarrior_disconnect(struct usb_interface *interface)
dev = usb_get_intfdata(interface);
mutex_lock(&iowarrior_open_disc_lock);
usb_set_intfdata(interface, NULL);
- /* prevent device read, write and ioctl */
- dev->present = 0;
minor = dev->minor;
mutex_unlock(&iowarrior_open_disc_lock);
@@ -878,8 +876,7 @@ static void iowarrior_disconnect(struct usb_interface *interface)
mutex_lock(&dev->mutex);
/* prevent device read, write and ioctl */
-
- mutex_unlock(&dev->mutex);
+ dev->present = 0;
if (dev->opened) {
/* There is a process that holds a filedescriptor to the device ,
@@ -889,8 +886,10 @@ static void iowarrior_disconnect(struct usb_interface *interface)
usb_kill_urb(dev->int_in_urb);
wake_up_interruptible(&dev->read_wait);
wake_up_interruptible(&dev->write_wait);
+ mutex_unlock(&dev->mutex);
} else {
/* no process is using the device, cleanup now */
+ mutex_unlock(&dev->mutex);
iowarrior_delete(dev);
}
--
2.23.0
^ permalink raw reply related [flat|nested] 3+ messages in thread
* [PATCH 2/6] USB: iowarrior: fix use-after-free on release
[not found] <20191009104846.5925-1-johan@kernel.org>
2019-10-09 10:48 ` [PATCH 1/6] USB: iowarrior: fix use-after-free on disconnect Johan Hovold
@ 2019-10-09 10:48 ` Johan Hovold
2019-10-09 10:48 ` [PATCH 3/6] USB: iowarrior: fix use-after-free after driver unbind Johan Hovold
2 siblings, 0 replies; 3+ messages in thread
From: Johan Hovold @ 2019-10-09 10:48 UTC (permalink / raw)
To: Greg Kroah-Hartman
Cc: Oliver Neukum, Valentin Vidic, linux-usb, linux-kernel,
Johan Hovold, stable
The driver was accessing its struct usb_interface from its release()
callback without holding a reference. This would lead to a
use-after-free whenever debugging was enabled and the device was
disconnected while its character device was open.
Fixes: 549e83500b80 ("USB: iowarrior: Convert local dbg macro to dev_dbg")
Cc: stable <stable@vger.kernel.org> # 3.16
Signed-off-by: Johan Hovold <johan@kernel.org>
---
drivers/usb/misc/iowarrior.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/misc/iowarrior.c b/drivers/usb/misc/iowarrior.c
index 4fe1d3267b3c..6841267820c6 100644
--- a/drivers/usb/misc/iowarrior.c
+++ b/drivers/usb/misc/iowarrior.c
@@ -243,6 +243,7 @@ static inline void iowarrior_delete(struct iowarrior *dev)
kfree(dev->int_in_buffer);
usb_free_urb(dev->int_in_urb);
kfree(dev->read_queue);
+ usb_put_intf(dev->interface);
kfree(dev);
}
@@ -764,7 +765,7 @@ static int iowarrior_probe(struct usb_interface *interface,
init_waitqueue_head(&dev->write_wait);
dev->udev = udev;
- dev->interface = interface;
+ dev->interface = usb_get_intf(interface);
iface_desc = interface->cur_altsetting;
dev->product_id = le16_to_cpu(udev->descriptor.idProduct);
--
2.23.0
^ permalink raw reply related [flat|nested] 3+ messages in thread
* [PATCH 3/6] USB: iowarrior: fix use-after-free after driver unbind
[not found] <20191009104846.5925-1-johan@kernel.org>
2019-10-09 10:48 ` [PATCH 1/6] USB: iowarrior: fix use-after-free on disconnect Johan Hovold
2019-10-09 10:48 ` [PATCH 2/6] USB: iowarrior: fix use-after-free on release Johan Hovold
@ 2019-10-09 10:48 ` Johan Hovold
2 siblings, 0 replies; 3+ messages in thread
From: Johan Hovold @ 2019-10-09 10:48 UTC (permalink / raw)
To: Greg Kroah-Hartman
Cc: Oliver Neukum, Valentin Vidic, linux-usb, linux-kernel,
Johan Hovold, stable
Make sure to stop also the asynchronous write URBs on disconnect() to
avoid use-after-free in the completion handler after driver unbind.
Fixes: 946b960d13c1 ("USB: add driver for iowarrior devices.")
Cc: stable <stable@vger.kernel.org> # 2.6.21: 51a2f077c44e ("USB: introduce usb_anchor")
Signed-off-by: Johan Hovold <johan@kernel.org>
---
drivers/usb/misc/iowarrior.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/usb/misc/iowarrior.c b/drivers/usb/misc/iowarrior.c
index 6841267820c6..f405fa734bcc 100644
--- a/drivers/usb/misc/iowarrior.c
+++ b/drivers/usb/misc/iowarrior.c
@@ -87,6 +87,7 @@ struct iowarrior {
char chip_serial[9]; /* the serial number string of the chip connected */
int report_size; /* number of bytes in a report */
u16 product_id;
+ struct usb_anchor submitted;
};
/*--------------*/
@@ -425,11 +426,13 @@ static ssize_t iowarrior_write(struct file *file,
retval = -EFAULT;
goto error;
}
+ usb_anchor_urb(int_out_urb, &dev->submitted);
retval = usb_submit_urb(int_out_urb, GFP_KERNEL);
if (retval) {
dev_dbg(&dev->interface->dev,
"submit error %d for urb nr.%d\n",
retval, atomic_read(&dev->write_busy));
+ usb_unanchor_urb(int_out_urb);
goto error;
}
/* submit was ok */
@@ -770,6 +773,8 @@ static int iowarrior_probe(struct usb_interface *interface,
iface_desc = interface->cur_altsetting;
dev->product_id = le16_to_cpu(udev->descriptor.idProduct);
+ init_usb_anchor(&dev->submitted);
+
res = usb_find_last_int_in_endpoint(iface_desc, &dev->int_in_endpoint);
if (res) {
dev_err(&interface->dev, "no interrupt-in endpoint found\n");
@@ -885,6 +890,7 @@ static void iowarrior_disconnect(struct usb_interface *interface)
Deleting the device is postponed until close() was called.
*/
usb_kill_urb(dev->int_in_urb);
+ usb_kill_anchored_urbs(&dev->submitted);
wake_up_interruptible(&dev->read_wait);
wake_up_interruptible(&dev->write_wait);
mutex_unlock(&dev->mutex);
--
2.23.0
^ permalink raw reply related [flat|nested] 3+ messages in thread
end of thread, other threads:[~2019-10-09 10:49 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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[not found] <20191009104846.5925-1-johan@kernel.org>
2019-10-09 10:48 ` [PATCH 1/6] USB: iowarrior: fix use-after-free on disconnect Johan Hovold
2019-10-09 10:48 ` [PATCH 2/6] USB: iowarrior: fix use-after-free on release Johan Hovold
2019-10-09 10:48 ` [PATCH 3/6] USB: iowarrior: fix use-after-free after driver unbind Johan Hovold
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