From patchwork Wed Jan 28 22:19:49 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kamal Mostafa X-Patchwork-Id: 434029 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id 7767614012C; Thu, 29 Jan 2015 09:22:36 +1100 (AEDT) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1YGb0K-0007Qa-91; Wed, 28 Jan 2015 22:22:32 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1YGaxk-0005zs-9J for kernel-team@lists.ubuntu.com; Wed, 28 Jan 2015 22:19:52 +0000 Received: from c-76-102-4-12.hsd1.ca.comcast.net ([76.102.4.12] helo=fourier) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1YGaxj-00030s-GZ; Wed, 28 Jan 2015 22:19:51 +0000 Received: from kamal by fourier with local (Exim 4.82) (envelope-from ) id 1YGaxh-0002qu-Po; Wed, 28 Jan 2015 14:19:49 -0800 From: Kamal Mostafa To: Jens Axboe Subject: [3.13.y-ckt stable] Patch "genhd: check for int overflow in disk_expand_part_tbl()" has been added to staging queue Date: Wed, 28 Jan 2015 14:19:49 -0800 Message-Id: <1422483589-10933-1-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 X-Extended-Stable: 3.13 Cc: Kamal Mostafa , kernel-team@lists.ubuntu.com, David Ramos X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com This is a note to let you know that I have just added a patch titled genhd: check for int overflow in disk_expand_part_tbl() to the linux-3.13.y-queue branch of the 3.13.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue This patch is scheduled to be released in version 3.13.11-ckt15. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.13.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From deee66d98cc60d2a89934ce2b87d7c78c2e31906 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Wed, 19 Nov 2014 13:06:22 -0700 Subject: genhd: check for int overflow in disk_expand_part_tbl() commit 5fabcb4c33fe11c7e3afdf805fde26c1a54d0953 upstream. We can get here from blkdev_ioctl() -> blkpg_ioctl() -> add_partition() with a user passed in partno value. If we pass in 0x7fffffff, the new target in disk_expand_part_tbl() overflows the 'int' and we access beyond the end of ptbl->part[] and even write to it when we do the rcu_assign_pointer() to assign the new partition. Reported-by: David Ramos Signed-off-by: Jens Axboe Signed-off-by: Kamal Mostafa --- block/genhd.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) -- 1.9.1 diff --git a/block/genhd.c b/block/genhd.c index e6723bd..a8d586a 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -1070,9 +1070,16 @@ int disk_expand_part_tbl(struct gendisk *disk, int partno) struct disk_part_tbl *old_ptbl = disk->part_tbl; struct disk_part_tbl *new_ptbl; int len = old_ptbl ? old_ptbl->len : 0; - int target = partno + 1; + int i, target; size_t size; - int i; + + /* + * check for int overflow, since we can get here from blkpg_ioctl() + * with a user passed 'partno'. + */ + target = partno + 1; + if (target < 0) + return -EINVAL; /* disk_max_parts() is zero during initialization, ignore if so */ if (disk_max_parts(disk) && target > disk_max_parts(disk))