diff options
| -rw-r--r-- | libre/linux-libre/CVE-2014-0196.patch | 80 | ||||
| -rw-r--r-- | libre/linux-libre/PKGBUILD | 9 |
2 files changed, 87 insertions, 2 deletions
diff --git a/libre/linux-libre/CVE-2014-0196.patch b/libre/linux-libre/CVE-2014-0196.patch new file mode 100644 index 000000000..a58707d56 --- /dev/null +++ b/libre/linux-libre/CVE-2014-0196.patch @@ -0,0 +1,80 @@ +From 4291086b1f081b869c6d79e5b7441633dc3ace00 Mon Sep 17 00:00:00 2001 +From: Peter Hurley <peter@hurleysoftware.com> +Date: Sat, 3 May 2014 14:04:59 +0200 +Subject: n_tty: Fix n_tty_write crash when echoing in raw mode + +The tty atomic_write_lock does not provide an exclusion guarantee for +the tty driver if the termios settings are LECHO & !OPOST. And since +it is unexpected and not allowed to call TTY buffer helpers like +tty_insert_flip_string concurrently, this may lead to crashes when +concurrect writers call pty_write. In that case the following two +writers: +* the ECHOing from a workqueue and +* pty_write from the process +race and can overflow the corresponding TTY buffer like follows. + +If we look into tty_insert_flip_string_fixed_flag, there is: + int space = __tty_buffer_request_room(port, goal, flags); + struct tty_buffer *tb = port->buf.tail; + ... + memcpy(char_buf_ptr(tb, tb->used), chars, space); + ... + tb->used += space; + +so the race of the two can result in something like this: + A B +__tty_buffer_request_room + __tty_buffer_request_room +memcpy(buf(tb->used), ...) +tb->used += space; + memcpy(buf(tb->used), ...) ->BOOM + +B's memcpy is past the tty_buffer due to the previous A's tb->used +increment. + +Since the N_TTY line discipline input processing can output +concurrently with a tty write, obtain the N_TTY ldisc output_lock to +serialize echo output with normal tty writes. This ensures the tty +buffer helper tty_insert_flip_string is not called concurrently and +everything is fine. + +Note that this is nicely reproducible by an ordinary user using +forkpty and some setup around that (raw termios + ECHO). And it is +present in kernels at least after commit +d945cb9cce20ac7143c2de8d88b187f62db99bdc (pty: Rework the pty layer to +use the normal buffering logic) in 2.6.31-rc3. + +js: add more info to the commit log +js: switch to bool +js: lock unconditionally +js: lock only the tty->ops->write call + +References: CVE-2014-0196 +Reported-and-tested-by: Jiri Slaby <jslaby@suse.cz> +Signed-off-by: Peter Hurley <peter@hurleysoftware.com> +Signed-off-by: Jiri Slaby <jslaby@suse.cz> +Cc: Linus Torvalds <torvalds@linux-foundation.org> +Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> +Cc: <stable@vger.kernel.org> +Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> + +diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c +index 41fe8a0..fe9d129 100644 +--- a/drivers/tty/n_tty.c ++++ b/drivers/tty/n_tty.c +@@ -2353,8 +2353,12 @@ static ssize_t n_tty_write(struct tty_struct *tty, struct file *file, + if (tty->ops->flush_chars) + tty->ops->flush_chars(tty); + } else { ++ struct n_tty_data *ldata = tty->disc_data; ++ + while (nr > 0) { ++ mutex_lock(&ldata->output_lock); + c = tty->ops->write(tty, b, nr); ++ mutex_unlock(&ldata->output_lock); + if (c < 0) { + retval = c; + goto break_out; +-- +cgit v0.10.1-7-g08dc + diff --git a/libre/linux-libre/PKGBUILD b/libre/linux-libre/PKGBUILD index db1d1c223..663e3c916 100644 --- a/libre/linux-libre/PKGBUILD +++ b/libre/linux-libre/PKGBUILD @@ -1,4 +1,4 @@ -# $Id: PKGBUILD 212093 2014-05-06 20:49:41Z tpowa $ +# $Id: PKGBUILD 212325 2014-05-12 18:58:13Z tpowa $ # Maintainer: Tobias Powalowski <tpowa@archlinux.org> # Maintainer: Thomas Baechler <thomas@archlinux.org> # Maintainer (Parabola): André Silva <emulatorman@parabola.nu> @@ -12,7 +12,7 @@ pkgbase=linux-libre # Build stock -LIBRE kernel _basekernel=3.14 _sublevel=3 pkgver=${_basekernel}.${_sublevel} -pkgrel=1 +pkgrel=2 _lxopkgver=${_basekernel}.3 # nearly always the same as pkgver arch=('i686' 'x86_64' 'mips64el') url="http://linux-libre.fsfla.org/" @@ -21,6 +21,7 @@ makedepends=('xmlto' 'docbook-xsl' 'kmod' 'inetutils' 'bc') options=('!strip') source=("http://linux-libre.fsfla.org/pub/linux-libre/releases/${_basekernel}-gnu/linux-libre-${_basekernel}-gnu.tar.xz" "http://linux-libre.fsfla.org/pub/linux-libre/releases/${pkgver}-gnu/patch-${_basekernel}-gnu-${pkgver}-gnu.xz" + 'CVE-2014-0196.patch' # the main kernel config files 'config.i686' 'config.x86_64' # standard config files for mkinitcpio ramdisk @@ -43,6 +44,7 @@ source=("http://linux-libre.fsfla.org/pub/linux-libre/releases/${_basekernel}-gn "http://www.linux-libre.fsfla.org/pub/linux-libre/lemote/gnewsense/pool/debuginfo/linux-patches-${_lxopkgver}-gnu_0loongsonlibre_mipsel.tar.xz") sha256sums=('477555c709b9407fe37dbd70d3331ff9dde1f9d874aba2741f138d07ae6f281b' 'fcd8398a41a7e55e44123857342fd9041ae1bdacbcf8c5099a53293c96e6fba6' + '56d6dc13617645184e2a14b2ee466ccba5241961953f4950aed7377bc34902d7' '71891ae6903598f4686e86fdb0d371ff9e179e8dac1d2cf60ca16c5190916745' 'fca0060bde385e2c292489087af0aa5f48da594221a6d162fc6f8ba2159571e8' 'dfe01c93d83cdac9ca502715ceb6ac9502d327c939fec2e3052a5a58422dc176' @@ -81,6 +83,9 @@ prepare() { # add freedo as boot logo patch -p1 -i "${srcdir}/boot-logo.patch" + # fix upstream CVE-2014-0196 + patch -p1 -i "${srcdir}/CVE-2014-0196.patch" + # add latest fixes from stable queue, if needed # http://git.kernel.org/?p=linux/kernel/git/stable/stable-queue.git |