This is a note to let you know that I've just added the patch titled HID: usbhid: free raw_report buffers in usbhid_stop to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: hid-usbhid-free-raw_report-buffers-in-usbhid_stop.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From f7744fa16b96da57187dc8e5634152d3b63d72de Mon Sep 17 00:00:00 2001 From: Anirudh Rayabharam <mail@xxxxxxxxxxxxx> Date: Thu, 24 Jun 2021 00:10:29 +0530 Subject: HID: usbhid: free raw_report buffers in usbhid_stop From: Anirudh Rayabharam <mail@xxxxxxxxxxxxx> commit f7744fa16b96da57187dc8e5634152d3b63d72de upstream. Free the unsent raw_report buffers when the device is removed. Fixes a memory leak reported by syzbot at: https://syzkaller.appspot.com/bug?id=7b4fa7cb1a7c2d3342a2a8a6c53371c8c418ab47 Reported-by: syzbot+47b26cd837ececfc666d@xxxxxxxxxxxxxxxxxxxxxxxxx Tested-by: syzbot+47b26cd837ececfc666d@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Anirudh Rayabharam <mail@xxxxxxxxxxxxx> Signed-off-by: Jiri Kosina <jkosina@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/hid/usbhid/hid-core.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) --- a/drivers/hid/usbhid/hid-core.c +++ b/drivers/hid/usbhid/hid-core.c @@ -500,7 +500,7 @@ static void hid_ctrl(struct urb *urb) if (unplug) { usbhid->ctrltail = usbhid->ctrlhead; - } else { + } else if (usbhid->ctrlhead != usbhid->ctrltail) { usbhid->ctrltail = (usbhid->ctrltail + 1) & (HID_CONTROL_FIFO_SIZE - 1); if (usbhid->ctrlhead != usbhid->ctrltail && @@ -1185,9 +1185,20 @@ static void usbhid_stop(struct hid_devic usbhid->intf->needs_remote_wakeup = 0; clear_bit(HID_STARTED, &usbhid->iofl); + spin_lock_irq(&usbhid->lock); /* Sync with error and led handlers */ set_bit(HID_DISCONNECTED, &usbhid->iofl); + while (usbhid->ctrltail != usbhid->ctrlhead) { + if (usbhid->ctrl[usbhid->ctrltail].dir == USB_DIR_OUT) { + kfree(usbhid->ctrl[usbhid->ctrltail].raw_report); + usbhid->ctrl[usbhid->ctrltail].raw_report = NULL; + } + + usbhid->ctrltail = (usbhid->ctrltail + 1) & + (HID_CONTROL_FIFO_SIZE - 1); + } spin_unlock_irq(&usbhid->lock); + usb_kill_urb(usbhid->urbin); usb_kill_urb(usbhid->urbout); usb_kill_urb(usbhid->urbctrl); Patches currently in stable-queue which might be from mail@xxxxxxxxxxxxx are queue-4.9/hid-usbhid-free-raw_report-buffers-in-usbhid_stop.patch