From: Shuah Khan <skhan@linuxfoundation.org>
Date: Mon, 8 Mar 2021 03:53:28 +0000 (-0700)
Subject: usbip: fix vudc to check for stream socket
X-Git-Tag: v4.14.226~33
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=66ea0d31eec230385c0fc19f5abe26d9d49e0a0a;p=thirdparty%2Fkernel%2Fstable.git

usbip: fix vudc to check for stream socket

commit 6801854be94fe8819b3894979875ea31482f5658 upstream.

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/387a670316002324113ac7ea1e8b53f4085d0c95.1615171203.git.skhan@linuxfoundation.org
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 7efa374a49703..e3f7c76d19562 100644
--- a/drivers/usb/usbip/vudc_sysfs.c
+++ b/drivers/usb/usbip/vudc_sysfs.c
@@ -24,6 +24,7 @@
 #include <linux/usb/ch9.h>
 #include <linux/sysfs.h>
 #include <linux/kthread.h>
+#include <linux/file.h>
 #include <linux/byteorder/generic.h>
 
 #include "usbip_common.h"
@@ -150,6 +151,13 @@ static ssize_t store_sockfd(struct device *dev, struct device_attribute *attr,
 			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);
@@ -189,6 +197,8 @@ static ssize_t store_sockfd(struct device *dev, struct device_attribute *attr,
 
 	return count;
 
+sock_err:
+	sockfd_put(socket);
 unlock_ud:
 	spin_unlock_irq(&udc->ud.lock);
 unlock: