The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 6801854be94fe8819b3894979875ea31482f5658 Mon Sep 17 00:00:00 2001

From: Shuah Khan skhan@linuxfoundation.org Date: Sun, 7 Mar 2021 20:53:28 -0700 Subject: [PATCH] usbip: fix vudc to check for stream socket

Fix usbip_sockfd_store() to validate the passed in file descriptor is a stream socket. If the file descriptor passed was a SOCK_DGRAM socket, sock_recvmsg() can't detect end of stream.

Cc: stable@vger.kernel.org Suggested-by: Tetsuo Handa penguin-kernel@I-love.SAKURA.ne.jp Signed-off-by: Shuah Khan skhan@linuxfoundation.org Link: https://lore.kernel.org/r/387a670316002324113ac7ea1e8b53f4085d0c95.161517120... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

diff --git a/drivers/usb/usbip/vudc_sysfs.c b/drivers/usb/usbip/vudc_sysfs.c index 100f680c572a..83a0c59a3de8 100644 --- a/drivers/usb/usbip/vudc_sysfs.c +++ b/drivers/usb/usbip/vudc_sysfs.c @@ -138,6 +138,13 @@ static ssize_t usbip_sockfd_store(struct device *dev, struct device_attribute *a goto unlock_ud; }

+ if (socket->type != SOCK_STREAM) { + dev_err(dev, "Expecting SOCK_STREAM - found %d", + socket->type); + ret = -EINVAL; + goto sock_err; + } + udc->ud.tcp_socket = socket;

spin_unlock_irq(&udc->ud.lock); @@ -177,6 +184,8 @@ static ssize_t usbip_sockfd_store(struct device *dev, struct device_attribute *a

return count;

+sock_err: + sockfd_put(socket); unlock_ud: spin_unlock_irq(&udc->ud.lock); unlock: