This is a note to let you know that I've just added the patch titled usbip: fix stub_rx: get_pipe() to validate endpoint number 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: usbip-fix-stub_rx-get_pipe-to-validate-endpoint-number.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 635f545a7e8be7596b9b2b6a43cab6bbd5a88e43 Mon Sep 17 00:00:00 2001 From: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx> Date: Thu, 7 Dec 2017 14:16:47 -0700 Subject: usbip: fix stub_rx: get_pipe() to validate endpoint number From: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx> commit 635f545a7e8be7596b9b2b6a43cab6bbd5a88e43 upstream. get_pipe() routine doesn't validate the input endpoint number and uses to reference ep_in and ep_out arrays. Invalid endpoint number can trigger BUG(). Range check the epnum and returning error instead of calling BUG(). Change caller stub_recv_cmd_submit() to handle the get_pipe() error return. Reported-by: Secunia Research <vuln@xxxxxxxxxxx> Signed-off-by: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/usbip/stub_rx.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) --- a/drivers/usb/usbip/stub_rx.c +++ b/drivers/usb/usbip/stub_rx.c @@ -342,15 +342,15 @@ static int get_pipe(struct stub_device * struct usb_host_endpoint *ep; struct usb_endpoint_descriptor *epd = NULL; + if (epnum < 0 || epnum > 15) + goto err_ret; + if (dir == USBIP_DIR_IN) ep = udev->ep_in[epnum & 0x7f]; else ep = udev->ep_out[epnum & 0x7f]; - if (!ep) { - dev_err(&sdev->udev->dev, "no such endpoint?, %d\n", - epnum); - BUG(); - } + if (!ep) + goto err_ret; epd = &ep->desc; if (usb_endpoint_xfer_control(epd)) { @@ -381,9 +381,10 @@ static int get_pipe(struct stub_device * return usb_rcvisocpipe(udev, epnum); } +err_ret: /* NOT REACHED */ - dev_err(&sdev->udev->dev, "get pipe, epnum %d\n", epnum); - return 0; + dev_err(&sdev->udev->dev, "get pipe() invalid epnum %d\n", epnum); + return -1; } static void masking_bogus_flags(struct urb *urb) @@ -449,6 +450,9 @@ static void stub_recv_cmd_submit(struct struct usb_device *udev = sdev->udev; int pipe = get_pipe(sdev, pdu->base.ep, pdu->base.direction); + if (pipe == -1) + return; + priv = stub_priv_alloc(sdev, pdu); if (!priv) return; Patches currently in stable-queue which might be from shuahkh@xxxxxxxxxxxxxxx are queue-4.9/usbip-fix-stub_rx-harden-cmd_submit-path-to-handle-malicious-input.patch queue-4.9/usbip-fix-stub_send_ret_submit-vulnerability-to-null-transfer_buffer.patch queue-4.9/usbip-fix-stub_rx-get_pipe-to-validate-endpoint-number.patch