From eb5fd9e46c11ea41430d9c5bcc81d4583424216e Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Thu, 11 Feb 2021 17:09:44 +0200 Subject: [PATCH] usb: kbd: destroy device after console is stopped In case of IOMUX enabled it assumes that console devices in the list are available to get them stopped properly via ->stop() callback. However, the USB keyboard driver violates this assumption and tries to play tricks so the device get destroyed while being listed as an active console. Swap the order of device deregistration and IOMUX update along with converting to use iomux_replace_device() jelper to avoid the use-after-free. Fixes: 3cbcb2892809 ("usb: Fix usb_kbd_deregister when console-muxing is used") Fixes: 8a8348703081 ("dm: usb: Add a remove() method for USB keyboards") Reported-by: Nicolas Saenz Julienne Signed-off-by: Andy Shevchenko --- common/usb_kbd.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/common/usb_kbd.c b/common/usb_kbd.c index b316807844..60c6027e04 100644 --- a/common/usb_kbd.c +++ b/common/usb_kbd.c @@ -617,12 +617,12 @@ int usb_kbd_deregister(int force) if (dev) { usb_kbd_dev = (struct usb_device *)dev->priv; data = usb_kbd_dev->privptr; - if (stdio_deregister_dev(dev, force) != 0) - return 1; #if CONFIG_IS_ENABLED(CONSOLE_MUX) - if (iomux_doenv(stdin, env_get("stdin")) != 0) + if (iomux_replace_device(stdin, DEVNAME, force ? "nulldev" : "")) return 1; #endif + if (stdio_deregister_dev(dev, force) != 0) + return 1; #ifdef CONFIG_SYS_USB_EVENT_POLL_VIA_INT_QUEUE destroy_int_queue(usb_kbd_dev, data->intq); #endif @@ -660,16 +660,16 @@ static int usb_kbd_remove(struct udevice *dev) goto err; } data = udev->privptr; - if (stdio_deregister_dev(sdev, true)) { - ret = -EPERM; - goto err; - } #if CONFIG_IS_ENABLED(CONSOLE_MUX) - if (iomux_doenv(stdin, env_get("stdin"))) { + if (iomux_replace_device(stdin, DEVNAME, "nulldev")) { ret = -ENOLINK; goto err; } #endif + if (stdio_deregister_dev(sdev, true)) { + ret = -EPERM; + goto err; + } #ifdef CONFIG_SYS_USB_EVENT_POLL_VIA_INT_QUEUE destroy_int_queue(udev, data->intq); #endif