From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:39944 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965375AbdAFPcs (ORCPT ); Fri, 6 Jan 2017 10:32:48 -0500 Subject: Patch "sg_write()/bsg_write() is not fit to be called under KERNEL_DS" has been added to the 4.9-stable tree To: viro@zeniv.linux.org.uk, gregkh@linuxfoundation.org Cc: , From: Date: Fri, 06 Jan 2017 16:31:32 +0100 Message-ID: <14837166924208@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled sg_write()/bsg_write() is not fit to be called under KERNEL_DS 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: sg_write-bsg_write-is-not-fit-to-be-called-under-kernel_ds.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 know about it. >>From 128394eff343fc6d2f32172f03e24829539c5835 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Fri, 16 Dec 2016 13:42:06 -0500 Subject: sg_write()/bsg_write() is not fit to be called under KERNEL_DS From: Al Viro commit 128394eff343fc6d2f32172f03e24829539c5835 upstream. Both damn things interpret userland pointers embedded into the payload; worse, they are actually traversing those. Leaving aside the bad API design, this is very much _not_ safe to call with KERNEL_DS. Bail out early if that happens. Signed-off-by: Al Viro Signed-off-by: Greg Kroah-Hartman --- block/bsg.c | 3 +++ drivers/scsi/sg.c | 3 +++ 2 files changed, 6 insertions(+) --- a/block/bsg.c +++ b/block/bsg.c @@ -655,6 +655,9 @@ bsg_write(struct file *file, const char dprintk("%s: write %Zd bytes\n", bd->name, count); + if (unlikely(segment_eq(get_fs(), KERNEL_DS))) + return -EINVAL; + bsg_set_block(bd, file); bytes_written = 0; --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -581,6 +581,9 @@ sg_write(struct file *filp, const char _ sg_io_hdr_t *hp; unsigned char cmnd[SG_MAX_CDB_SIZE]; + if (unlikely(segment_eq(get_fs(), KERNEL_DS))) + return -EINVAL; + if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) return -ENXIO; SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, Patches currently in stable-queue which might be from viro@zeniv.linux.org.uk are queue-4.9/sg_write-bsg_write-is-not-fit-to-be-called-under-kernel_ds.patch queue-4.9/nfs_write_end-fix-handling-of-short-copies.patch