From: Dan Rosenberg <drosenberg@vsecurity.com>
To: linux-usb@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, security@kernel.org, stable@kernel.org
Subject: [PATCH] drivers/usb/serial/mos*: prevent reading uninitialized stack memory
Date: Wed, 15 Sep 2010 17:44:16 -0400 [thread overview]
Message-ID: <1284587056.6275.100.camel@dan> (raw)
The TIOCGICOUNT device ioctl in both mos7720.c and mos7840.c allows
unprivileged users to read uninitialized stack memory, because the
"reserved" member of the serial_icounter_struct struct declared on the
stack is not altered or zeroed before being copied back to the user.
This patch takes care of it.
Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com>
diff -urp linux-2.6.35.4.orig/drivers/usb/serial/mos7720.c linux-2.6.35.4/drivers/usb/serial/mos7720.c
--- linux-2.6.35.4.orig/drivers/usb/serial/mos7720.c 2010-08-26 19:47:12.000000000 -0400
+++ linux-2.6.35.4/drivers/usb/serial/mos7720.c 2010-09-15 11:42:01.877375361 -0400
@@ -2024,6 +2024,9 @@ static int mos7720_ioctl(struct tty_stru
case TIOCGICOUNT:
cnow = mos7720_port->icount;
+
+ memset(&icount, 0, sizeof(struct serial_icounter_struct));
+
icount.cts = cnow.cts;
icount.dsr = cnow.dsr;
icount.rng = cnow.rng;
diff -urp linux-2.6.35.4.orig/drivers/usb/serial/mos7840.c linux-2.6.35.4/drivers/usb/serial/mos7840.c
--- linux-2.6.35.4.orig/drivers/usb/serial/mos7840.c 2010-08-26 19:47:12.000000000 -0400
+++ linux-2.6.35.4/drivers/usb/serial/mos7840.c 2010-09-15 11:42:39.237375173 -0400
@@ -2273,6 +2273,9 @@ static int mos7840_ioctl(struct tty_stru
case TIOCGICOUNT:
cnow = mos7840_port->icount;
smp_rmb();
+
+ memset(&icount, 0, sizeof(struct serial_icounter_struct));
+
icount.cts = cnow.cts;
icount.dsr = cnow.dsr;
icount.rng = cnow.rng;
next reply other threads:[~2010-09-15 21:50 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-09-15 21:44 Dan Rosenberg [this message]
2010-09-16 8:39 ` [PATCH] drivers/usb/serial/mos*: prevent reading uninitialized stack memory Alan Cox
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=1284587056.6275.100.camel@dan \
--to=drosenberg@vsecurity.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=security@kernel.org \
--cc=stable@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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.