2022-08-19 10:52:13

by Dragos-Marian Panait

[permalink] [raw]
Subject: [PATCH 5.10 0/1] ath9k: fix use-after-free in ath9k_hif_usb_rx_cb

The following commit is needed to fix CVE-2022-1679:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0ac4827f78c7ffe8eef074bc010e7e34bc22f533

Pavel Skripkin (1):
ath9k: fix use-after-free in ath9k_hif_usb_rx_cb

drivers/net/wireless/ath/ath9k/htc.h | 10 +++++-----
drivers/net/wireless/ath/ath9k/htc_drv_init.c | 3 ++-
2 files changed, 7 insertions(+), 6 deletions(-)


base-commit: 6eae1503ddf94b4c3581092d566b17ed12d80f20
--
2.37.1


2022-08-19 10:52:13

by Dragos-Marian Panait

[permalink] [raw]
Subject: [PATCH 5.10 1/1] ath9k: fix use-after-free in ath9k_hif_usb_rx_cb

From: Pavel Skripkin <[email protected]>

commit 0ac4827f78c7ffe8eef074bc010e7e34bc22f533 upstream.

Syzbot reported use-after-free Read in ath9k_hif_usb_rx_cb() [0]. The
problem was in incorrect htc_handle->drv_priv initialization.

Probable call trace which can trigger use-after-free:

ath9k_htc_probe_device()
/* htc_handle->drv_priv = priv; */
ath9k_htc_wait_for_target() <--- Failed
ieee80211_free_hw() <--- priv pointer is freed

<IRQ>
...
ath9k_hif_usb_rx_cb()
ath9k_hif_usb_rx_stream()
RX_STAT_INC() <--- htc_handle->drv_priv access

In order to not add fancy protection for drv_priv we can move
htc_handle->drv_priv initialization at the end of the
ath9k_htc_probe_device() and add helper macro to make
all *_STAT_* macros NULL safe, since syzbot has reported related NULL
deref in that macros [1]

Link: https://syzkaller.appspot.com/bug?id=6ead44e37afb6866ac0c7dd121b4ce07cb665f60 [0]
Link: https://syzkaller.appspot.com/bug?id=b8101ffcec107c0567a0cd8acbbacec91e9ee8de [1]
Fixes: fb9987d0f748 ("ath9k_htc: Support for AR9271 chipset.")
Reported-and-tested-by: [email protected]
Reported-and-tested-by: [email protected]
Signed-off-by: Pavel Skripkin <[email protected]>
Acked-by: Toke Høiland-Jørgensen <[email protected]>
Signed-off-by: Kalle Valo <[email protected]>
Link: https://lore.kernel.org/r/d57bbedc857950659bfacac0ab48790c1eda00c8.1655145743.git.paskripkin@gmail.com
Signed-off-by: Dragos-Marian Panait <[email protected]>
---
drivers/net/wireless/ath/ath9k/htc.h | 10 +++++-----
drivers/net/wireless/ath/ath9k/htc_drv_init.c | 3 ++-
2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/htc.h b/drivers/net/wireless/ath/ath9k/htc.h
index 6b45e63fae4b..e3d546ef71dd 100644
--- a/drivers/net/wireless/ath/ath9k/htc.h
+++ b/drivers/net/wireless/ath/ath9k/htc.h
@@ -327,11 +327,11 @@ static inline struct ath9k_htc_tx_ctl *HTC_SKB_CB(struct sk_buff *skb)
}

#ifdef CONFIG_ATH9K_HTC_DEBUGFS
-
-#define TX_STAT_INC(c) (hif_dev->htc_handle->drv_priv->debug.tx_stats.c++)
-#define TX_STAT_ADD(c, a) (hif_dev->htc_handle->drv_priv->debug.tx_stats.c += a)
-#define RX_STAT_INC(c) (hif_dev->htc_handle->drv_priv->debug.skbrx_stats.c++)
-#define RX_STAT_ADD(c, a) (hif_dev->htc_handle->drv_priv->debug.skbrx_stats.c += a)
+#define __STAT_SAFE(expr) (hif_dev->htc_handle->drv_priv ? (expr) : 0)
+#define TX_STAT_INC(c) __STAT_SAFE(hif_dev->htc_handle->drv_priv->debug.tx_stats.c++)
+#define TX_STAT_ADD(c, a) __STAT_SAFE(hif_dev->htc_handle->drv_priv->debug.tx_stats.c += a)
+#define RX_STAT_INC(c) __STAT_SAFE(hif_dev->htc_handle->drv_priv->debug.skbrx_stats.c++)
+#define RX_STAT_ADD(c, a) __STAT_SAFE(hif_dev->htc_handle->drv_priv->debug.skbrx_stats.c += a)
#define CAB_STAT_INC priv->debug.tx_stats.cab_queued++

#define TX_QSTAT_INC(q) (priv->debug.tx_stats.queue_stats[q]++)
diff --git a/drivers/net/wireless/ath/ath9k/htc_drv_init.c b/drivers/net/wireless/ath/ath9k/htc_drv_init.c
index ff61ae34ecdf..07ac88fb1c57 100644
--- a/drivers/net/wireless/ath/ath9k/htc_drv_init.c
+++ b/drivers/net/wireless/ath/ath9k/htc_drv_init.c
@@ -944,7 +944,6 @@ int ath9k_htc_probe_device(struct htc_target *htc_handle, struct device *dev,
priv->hw = hw;
priv->htc = htc_handle;
priv->dev = dev;
- htc_handle->drv_priv = priv;
SET_IEEE80211_DEV(hw, priv->dev);

ret = ath9k_htc_wait_for_target(priv);
@@ -965,6 +964,8 @@ int ath9k_htc_probe_device(struct htc_target *htc_handle, struct device *dev,
if (ret)
goto err_init;

+ htc_handle->drv_priv = priv;
+
return 0;

err_init:
--
2.37.1

2022-08-19 11:28:47

by Greg KH

[permalink] [raw]
Subject: Re: [PATCH 5.10 0/1] ath9k: fix use-after-free in ath9k_hif_usb_rx_cb

On Fri, Aug 19, 2022 at 01:38:51PM +0300, Dragos-Marian Panait wrote:
> The following commit is needed to fix CVE-2022-1679:
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0ac4827f78c7ffe8eef074bc010e7e34bc22f533
>
> Pavel Skripkin (1):
> ath9k: fix use-after-free in ath9k_hif_usb_rx_cb
>
> drivers/net/wireless/ath/ath9k/htc.h | 10 +++++-----
> drivers/net/wireless/ath/ath9k/htc_drv_init.c | 3 ++-
> 2 files changed, 7 insertions(+), 6 deletions(-)
>
>
> base-commit: 6eae1503ddf94b4c3581092d566b17ed12d80f20
> --
> 2.37.1
>

This is already queued up for 5.10. You forgot the backports to older
kernels, which is also already queued up.

thanks,

greg k-h

2022-08-19 12:24:52

by Dragos-Marian Panait

[permalink] [raw]
Subject: Re: [PATCH 5.10 0/1] ath9k: fix use-after-free in ath9k_hif_usb_rx_cb

Hi Greg,

On 19.08.2022 14:23, Greg KH wrote:
> [Please note: This e-mail is from an EXTERNAL e-mail address]
>
> On Fri, Aug 19, 2022 at 01:38:51PM +0300, Dragos-Marian Panait wrote:
>> The following commit is needed to fix CVE-2022-1679:
>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0ac4827f78c7ffe8eef074bc010e7e34bc22f533
>>
>> Pavel Skripkin (1):
>> ath9k: fix use-after-free in ath9k_hif_usb_rx_cb
>>
>> drivers/net/wireless/ath/ath9k/htc.h | 10 +++++-----
>> drivers/net/wireless/ath/ath9k/htc_drv_init.c | 3 ++-
>> 2 files changed, 7 insertions(+), 6 deletions(-)
>>
>>
>> base-commit: 6eae1503ddf94b4c3581092d566b17ed12d80f20
>> --
>> 2.37.1
>>
> This is already queued up for 5.10. You forgot the backports to older
> kernels, which is also already queued up.
Are you sure of this?
I can not find any patch for older kernels in the stable mailing
list(except for 5.15, 5.18, 5.19).

Thanks,
Dragos
>
> thanks,
>
> greg k-h

2022-08-19 15:41:32

by Greg KH

[permalink] [raw]
Subject: Re: [PATCH 5.10 0/1] ath9k: fix use-after-free in ath9k_hif_usb_rx_cb

On Fri, Aug 19, 2022 at 03:18:26PM +0300, Dragos-Marian Panait wrote:
> Hi Greg,
>
> On 19.08.2022 14:23, Greg KH wrote:
> > [Please note: This e-mail is from an EXTERNAL e-mail address]
> >
> > On Fri, Aug 19, 2022 at 01:38:51PM +0300, Dragos-Marian Panait wrote:
> > > The following commit is needed to fix CVE-2022-1679:
> > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0ac4827f78c7ffe8eef074bc010e7e34bc22f533
> > >
> > > Pavel Skripkin (1):
> > > ath9k: fix use-after-free in ath9k_hif_usb_rx_cb
> > >
> > > drivers/net/wireless/ath/ath9k/htc.h | 10 +++++-----
> > > drivers/net/wireless/ath/ath9k/htc_drv_init.c | 3 ++-
> > > 2 files changed, 7 insertions(+), 6 deletions(-)
> > >
> > >
> > > base-commit: 6eae1503ddf94b4c3581092d566b17ed12d80f20
> > > --
> > > 2.37.1
> > >
> > This is already queued up for 5.10. You forgot the backports to older
> > kernels, which is also already queued up.
> Are you sure of this?
> I can not find any patch for older kernels in the stable mailing list(except
> for 5.15, 5.18, 5.19).

Look in the stable-queue.git tree on git.kernel.org.

thanks,

greg k-h