pve-kernel-qoup/CVE-2017-1000380-ALSA-timer-Fix-race-between-read-and-ioctl.patch
Thomas Lamprecht d513484f62 add CVE fixes
CVE-2014-9900: net: Zeroing the structure ethtool_wolinfo in ethtool_get_wol()
CVE-2017-7346: drm/vmwgfx: limit the number of mip levels in vmw_gb_surface_define_ioctl()
CVE-2017-9605: drm/vmwgfx: Make sure backup_handle is always valid
CVE-2017-1000380:
 * ALSA: timer: Fix race between read and ioctl
 * ALSA: timer: Fix missing queue indices reset at SNDRV_TIMER_IOCTL_SELECT

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
2017-07-13 06:04:17 +02:00

84 lines
2.9 KiB
Diff

From 425e11483546f928109e5871a2c8b0fba3ddb3b4 Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai@suse.de>
Date: Wed, 21 Jun 2017 18:56:01 +0200
Subject: [PATCH 1/5] ALSA: timer: Fix race between read and ioctl
The read from ALSA timer device, the function snd_timer_user_tread(),
may access to an uninitialized struct snd_timer_user fields when the
read is concurrently performed while the ioctl like
snd_timer_user_tselect() is invoked. We have already fixed the races
among ioctls via a mutex, but we seem to have forgotten the race
between read vs ioctl.
This patch simply applies (more exactly extends the already applied
range of) tu->ioctl_lock in snd_timer_user_tread() for closing the
race window.
Reported-by: Alexander Potapenko <glider@google.com>
Tested-by: Alexander Potapenko <glider@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
CVE-2017-1000380
(cherry-picked from commit d11662f4f798b50d8c8743f433842c3e40fe3378)
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Acked-by: Seth Forshee <seth.forshee@canonical.com>
Acked-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
---
sound/core/timer.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/sound/core/timer.c b/sound/core/timer.c
index ad153149b231..3c11a6983f54 100644
--- a/sound/core/timer.c
+++ b/sound/core/timer.c
@@ -1963,6 +1963,7 @@ static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,
tu = file->private_data;
unit = tu->tread ? sizeof(struct snd_timer_tread) : sizeof(struct snd_timer_read);
+ mutex_lock(&tu->ioctl_lock);
spin_lock_irq(&tu->qlock);
while ((long)count - result >= unit) {
while (!tu->qused) {
@@ -1978,7 +1979,9 @@ static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,
add_wait_queue(&tu->qchange_sleep, &wait);
spin_unlock_irq(&tu->qlock);
+ mutex_unlock(&tu->ioctl_lock);
schedule();
+ mutex_lock(&tu->ioctl_lock);
spin_lock_irq(&tu->qlock);
remove_wait_queue(&tu->qchange_sleep, &wait);
@@ -1998,7 +2001,6 @@ static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,
tu->qused--;
spin_unlock_irq(&tu->qlock);
- mutex_lock(&tu->ioctl_lock);
if (tu->tread) {
if (copy_to_user(buffer, &tu->tqueue[qhead],
sizeof(struct snd_timer_tread)))
@@ -2008,7 +2010,6 @@ static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,
sizeof(struct snd_timer_read)))
err = -EFAULT;
}
- mutex_unlock(&tu->ioctl_lock);
spin_lock_irq(&tu->qlock);
if (err < 0)
@@ -2018,6 +2019,7 @@ static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,
}
_error:
spin_unlock_irq(&tu->qlock);
+ mutex_unlock(&tu->ioctl_lock);
return result > 0 ? result : err;
}
--
2.11.0