The Linux Kernel Mailing List
 help / color / mirror / Atom feed
From: Wenliang Fan <fanwlexca@gmail.com>
To: konishi.ryusuke@lab.ntt.co.jp
Cc: linux-nilfs@vger.kernel.org, linux-kernel@vger.kernel.org,
	Wenliang Fan <fanwlexca@gmail.com>
Subject: [PATCH] fs/nilfs2: Integer overflow in nilfs_ioctl_wrap_copy()
Date: Fri, 20 Dec 2013 15:46:08 +0800	[thread overview]
Message-ID: <1387525568-30025-1-git-send-email-fanwlexca@gmail.com> (raw)

The local variable 'pos' comes from userspace. If a large number was
passed, there would be an integer overflow in the following line:
	pos += n;

Signed-off-by: Wenliang Fan <fanwlexca@gmail.com>
---
 fs/nilfs2/ioctl.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c
index b44bdb2..b2bac9a 100644
--- a/fs/nilfs2/ioctl.c
+++ b/fs/nilfs2/ioctl.c
@@ -90,8 +90,13 @@ static int nilfs_ioctl_wrap_copy(struct the_nilfs *nilfs,
 		total += nr;
 		if ((size_t)nr < n)
 			break;
-		if (pos == ppos)
+		if (pos == ppos) {
+			if (pos > ULONG_MAX - n) {
+				ret = -EINVAL;
+				break;
+			}
 			pos += n;
+		}
 	}
 	argv->v_nmembs = total;
 
-- 
1.8.5.rc1.28.g7061504


             reply	other threads:[~2013-12-20  7:46 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-12-20  7:46 Wenliang Fan [this message]
2013-12-20  8:23 ` [PATCH] fs/nilfs2: Integer overflow in nilfs_ioctl_wrap_copy() Vyacheslav Dubeyko
  -- strict thread matches above, loose matches on Subject: below --
2013-12-28  2:28 Wenliang Fan
2013-12-30  6:40 ` Vyacheslav Dubeyko

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1387525568-30025-1-git-send-email-fanwlexca@gmail.com \
    --to=fanwlexca@gmail.com \
    --cc=konishi.ryusuke@lab.ntt.co.jp \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-nilfs@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox