From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756675Ab0LHAy6 (ORCPT ); Tue, 7 Dec 2010 19:54:58 -0500 Received: from kroah.org ([198.145.64.141]:58574 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756350Ab0LHAr5 (ORCPT ); Tue, 7 Dec 2010 19:47:57 -0500 X-Mailbox-Line: From gregkh@clark.site Tue Dec 7 16:44:33 2010 Message-Id: <20101208004433.810778286@clark.site> User-Agent: quilt/0.48-11.2 Date: Tue, 07 Dec 2010 16:44:41 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Antonio Ospite , Jiri Kosina Subject: [095/127] HID: hidraw, fix a NULL pointer dereference in hidraw_write In-Reply-To: <20101208004456.GA23578@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.32-stable review patch. If anyone has any objections, please let us know. ------------------ From: Antonio Ospite commit e42dee9a99a3ecd32b5c027e8f7411fb5bc11eb6 upstream. BUG: unable to handle kernel NULL pointer dereference at 0000000000000028 IP: [] hidraw_write+0x3b/0x116 [hid] [...] This is reproducible by disconnecting the device while userspace writes to dev node in a loop and doesn't check return values in order to exit the loop. Signed-off-by: Antonio Ospite Signed-off-by: Jiri Kosina Signed-off-by: Greg Kroah-Hartman --- drivers/hid/hidraw.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/drivers/hid/hidraw.c +++ b/drivers/hid/hidraw.c @@ -105,11 +105,15 @@ out: static ssize_t hidraw_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos) { unsigned int minor = iminor(file->f_path.dentry->d_inode); - /* FIXME: What stops hidraw_table going NULL */ - struct hid_device *dev = hidraw_table[minor]->hid; + struct hid_device *dev; __u8 *buf; int ret = 0; + if (!hidraw_table[minor]) + return -ENODEV; + + dev = hidraw_table[minor]->hid; + if (!dev->hid_output_raw_report) return -ENODEV;