From 22198e801db7542c59098a75bdab120bcbc42652 Mon Sep 17 00:00:00 2001 From: Phil Elwell Date: Wed, 30 Sep 2020 19:23:43 +0100 Subject: [PATCH] USB: gadget: f_hid: avoid crashes and log spam Disconnecting and reconnecting the USB cable can lead to crashes and a variety of kernel log spam. Try to fix or minimise both. See: https://github.com/raspberrypi/linux/issues/3870 Signed-off-by: Phil Elwell --- drivers/usb/gadget/function/f_hid.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) --- a/drivers/usb/gadget/function/f_hid.c +++ b/drivers/usb/gadget/function/f_hid.c @@ -344,6 +344,11 @@ static ssize_t f_hidg_write(struct file spin_lock_irqsave(&hidg->write_spinlock, flags); + if (!hidg->req) { + spin_unlock_irqrestore(&hidg->write_spinlock, flags); + return -ESHUTDOWN; + } + #define WRITE_COND (!hidg->write_pending) try_again: /* write queue */ @@ -364,7 +369,13 @@ try_again: count = min_t(unsigned, count, hidg->report_length); spin_unlock_irqrestore(&hidg->write_spinlock, flags); - status = copy_from_user(req->buf, buffer, count); + if (req) { + status = copy_from_user(req->buf, buffer, count); + } else { + ERROR(hidg->func.config->cdev, "hidg->req is NULL\n"); + status = -ESHUTDOWN; + goto release_write_pending; + } if (status != 0) { ERROR(hidg->func.config->cdev, @@ -393,6 +404,11 @@ try_again: spin_unlock_irqrestore(&hidg->write_spinlock, flags); + if (!hidg->in_ep->enabled) { + ERROR(hidg->func.config->cdev, "in_ep is disabled\n"); + status = -ESHUTDOWN; + goto release_write_pending; + } status = usb_ep_queue(hidg->in_ep, req, GFP_ATOMIC); if (status < 0) { ERROR(hidg->func.config->cdev,