From 26423f6f2fa84939743b9511ee2953a557aac1d5 Mon Sep 17 00:00:00 2001 From: Andrey Konovalov Date: Thu, 26 Oct 2023 22:01:12 +0200 Subject: [PATCH] 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 Signed-off-by: Andrey Konovalov Link: https://lore.kernel.org/r/0db45b1d7cc466e3d4d1ab353f61d63c977fbbc5.1698350424.git.andreyknvl@gmail.com Signed-off-by: Greg Kroah-Hartman (cherry picked from commit e8033bde451eddfb9b1bbd6e2d848c1b5c277222) Signed-off-by: Lee Jones Change-Id: I1509b30c9962d6e695b268c183e41bdd551f1780 --- drivers/usb/gadget/legacy/raw_gadget.c | 26 ++++++++++++++++---------- 1 file changed, 16 insertions(+), 10 deletions(-) diff --git a/drivers/usb/gadget/legacy/raw_gadget.c b/drivers/usb/gadget/legacy/raw_gadget.c index 8e4cb4f35040..3fdd7f8da3d3 100644 --- a/drivers/usb/gadget/legacy/raw_gadget.c +++ b/drivers/usb/gadget/legacy/raw_gadget.c @@ -624,12 +624,12 @@ static int raw_process_ep0_io(struct raw_dev *dev, struct usb_raw_ep_io *io, 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 @@ static int raw_process_ep0_io(struct raw_dev *dev, struct usb_raw_ep_io *io, "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 @@ static int raw_process_ep0_io(struct raw_dev *dev, struct usb_raw_ep_io *io, 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 @@ static int raw_process_ep_io(struct raw_dev *dev, struct usb_raw_ep_io *io, "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 @@ static int raw_process_ep_io(struct raw_dev *dev, struct usb_raw_ep_io *io, 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);