UPSTREAM: usb: raw-gadget: properly handle interrupted requests
Currently, if a USB request that was queued by Raw Gadget is interrupted
(via a signal), wait_for_completion_interruptible returns -ERESTARTSYS.
Raw Gadget then attempts to propagate this value to userspace as a return
value from its ioctls. However, when -ERESTARTSYS is returned by a syscall
handler, the kernel internally restarts the syscall.
This doesn't allow userspace applications to interrupt requests queued by
Raw Gadget (which is required when the emulated device is asked to switch
altsettings). It also violates the implied interface of Raw Gadget that a
single ioctl must only queue a single USB request.
Instead, make Raw Gadget do what GadgetFS does: check whether the request
was interrupted (dequeued with status == -ECONNRESET) and report -EINTR to
userspace.
Bug: 254441685
Fixes: f2c2e717642c ("usb: gadget: add raw-gadget interface")
Cc: stable <stable@kernel.org>
Signed-off-by: Andrey Konovalov <andreyknvl@gmail.com>
Link: https://lore.kernel.org/r/0db45b1d7cc466e3d4d1ab353f61d63c977fbbc5.1698350424.git.andreyknvl@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit e8033bde451eddfb9b1bbd6e2d848c1b5c277222)
Signed-off-by: Lee Jones <joneslee@google.com>
Change-Id: If8724001949230e99e44dfb8b65c545e573a2ca0
diff --git a/drivers/usb/gadget/legacy/raw_gadget.c b/drivers/usb/gadget/legacy/raw_gadget.c
index 8e4cb4f..3fdd7f8 100644
--- a/drivers/usb/gadget/legacy/raw_gadget.c
+++ b/drivers/usb/gadget/legacy/raw_gadget.c
@@ -624,12 +624,12 @@
if (WARN_ON(in && dev->ep0_out_pending)) {
ret = -ENODEV;
dev->state = STATE_DEV_FAILED;
- goto out_done;
+ goto out_unlock;
}
if (WARN_ON(!in && dev->ep0_in_pending)) {
ret = -ENODEV;
dev->state = STATE_DEV_FAILED;
- goto out_done;
+ goto out_unlock;
}
dev->req->buf = data;
@@ -644,7 +644,7 @@
"fail, usb_ep_queue returned %d\n", ret);
spin_lock_irqsave(&dev->lock, flags);
dev->state = STATE_DEV_FAILED;
- goto out_done;
+ goto out_queue_failed;
}
ret = wait_for_completion_interruptible(&dev->ep0_done);
@@ -653,13 +653,16 @@
usb_ep_dequeue(dev->gadget->ep0, dev->req);
wait_for_completion(&dev->ep0_done);
spin_lock_irqsave(&dev->lock, flags);
- goto out_done;
+ if (dev->ep0_status == -ECONNRESET)
+ dev->ep0_status = -EINTR;
+ goto out_interrupted;
}
spin_lock_irqsave(&dev->lock, flags);
- ret = dev->ep0_status;
-out_done:
+out_interrupted:
+ ret = dev->ep0_status;
+out_queue_failed:
dev->ep0_urb_queued = false;
out_unlock:
spin_unlock_irqrestore(&dev->lock, flags);
@@ -1021,7 +1024,7 @@
"fail, usb_ep_queue returned %d\n", ret);
spin_lock_irqsave(&dev->lock, flags);
dev->state = STATE_DEV_FAILED;
- goto out_done;
+ goto out_queue_failed;
}
ret = wait_for_completion_interruptible(&done);
@@ -1030,13 +1033,16 @@
usb_ep_dequeue(ep->ep, ep->req);
wait_for_completion(&done);
spin_lock_irqsave(&dev->lock, flags);
- goto out_done;
+ if (ep->status == -ECONNRESET)
+ ep->status = -EINTR;
+ goto out_interrupted;
}
spin_lock_irqsave(&dev->lock, flags);
- ret = ep->status;
-out_done:
+out_interrupted:
+ ret = ep->status;
+out_queue_failed:
ep->urb_queued = false;
out_unlock:
spin_unlock_irqrestore(&dev->lock, flags);
