[PATCH] net: ath9k: fix use-after-free in ath9k_hif_usb_rx_cb

[PATCH] net: ath9k: fix use-after-free in ath9k_hif_usb_rx_cb

[Pavel Skripkin]

Syzbot reported use-after-free Read in ath9k_hif_usb_rx_cb(). 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 save.

Also, I made whitespaces clean ups in *_STAT_* macros definitions
to make checkpatch.pl happy.

Fixes: fb9987d0f748 ("ath9k_htc: Support for AR9271 chipset.")
Reported-and-tested-by: syzbot+03110230a11411024147@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
---

Hi, ath9k maintainer/developers!

I know, that you do not like changes, that wasn't tested on real
hardware. I really don't access to this one, so I'd like you to test it on
real hardware piece, if you have one. At least, this patch was tested by
syzbot [1]

[1] https://syzkaller.appspot.com/bug?id=6ead44e37afb6866ac0c7dd121b4ce07cb665f60

---
 drivers/net/wireless/ath/ath9k/htc.h          | 11 ++++++-----
 drivers/net/wireless/ath/ath9k/htc_drv_init.c |  3 ++-
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/htc.h b/drivers/net/wireless/ath/ath9k/htc.h
index 0a1634238e67..c16b2a482e83 100644
--- a/drivers/net/wireless/ath/ath9k/htc.h
+++ b/drivers/net/wireless/ath/ath9k/htc.h
@@ -326,11 +326,12 @@ 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 CAB_STAT_INC   priv->debug.tx_stats.cab_queued++
+#define __STAT_SAVE(expr)	(hif_dev->htc_handle->drv_priv ? (expr) : 0)
+#define TX_STAT_INC(c)		__STAT_SAVE(hif_dev->htc_handle->drv_priv->debug.tx_stats.c++)
+#define TX_STAT_ADD(c, a)	__STAT_SAVE(hif_dev->htc_handle->drv_priv->debug.tx_stats.c += a)
+#define RX_STAT_INC(c)		__STAT_SAVE(hif_dev->htc_handle->drv_priv->debug.skbrx_stats.c++)
+#define RX_STAT_ADD(c, a)	__STAT_SAVE(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:
-- 
2.32.0

Re: [PATCH] net: ath9k: fix use-after-free in ath9k_hif_usb_rx_cb

[Pavel Skripkin]

On 8/4/21 10:48 PM, Pavel Skripkin wrote:
> Syzbot reported use-after-free Read in ath9k_hif_usb_rx_cb(). 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 save.
> 
> Also, I made whitespaces clean ups in *_STAT_* macros definitions
> to make checkpatch.pl happy.
> 
> Fixes: fb9987d0f748 ("ath9k_htc: Support for AR9271 chipset.")
> Reported-and-tested-by: syzbot+03110230a11411024147@syzkaller.appspotmail.com
> Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
> ---
> 
> Hi, ath9k maintainer/developers!
> 
> I know, that you do not like changes, that wasn't tested on real
> hardware. I really don't access to this one, so I'd like you to test it on
> real hardware piece, if you have one. At least, this patch was tested by
> syzbot [1]
> 
> [1] https://syzkaller.appspot.com/bug?id=6ead44e37afb6866ac0c7dd121b4ce07cb665f60
> 
> ---
>   drivers/net/wireless/ath/ath9k/htc.h          | 11 ++++++-----
>   drivers/net/wireless/ath/ath9k/htc_drv_init.c |  3 ++-
>   2 files changed, 8 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/net/wireless/ath/ath9k/htc.h b/drivers/net/wireless/ath/ath9k/htc.h
> index 0a1634238e67..c16b2a482e83 100644
> --- a/drivers/net/wireless/ath/ath9k/htc.h
> +++ b/drivers/net/wireless/ath/ath9k/htc.h
> @@ -326,11 +326,12 @@ 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 CAB_STAT_INC   priv->debug.tx_stats.cab_queued++
> +#define __STAT_SAVE(expr)	(hif_dev->htc_handle->drv_priv ? (expr) : 0)
> +#define TX_STAT_INC(c)		__STAT_SAVE(hif_dev->htc_handle->drv_priv->debug.tx_stats.c++)
> +#define TX_STAT_ADD(c, a)	__STAT_SAVE(hif_dev->htc_handle->drv_priv->debug.tx_stats.c += a)
> +#define RX_STAT_INC(c)		__STAT_SAVE(hif_dev->htc_handle->drv_priv->debug.skbrx_stats.c++)
> +#define RX_STAT_ADD(c, a)	__STAT_SAVE(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:
> 

Added missing LKML in CC. Sorry for confusion.


With regards,
Pavel Skripkin

Re: [PATCH] net: ath9k: fix use-after-free in ath9k_hif_usb_rx_cb

[Kalle Valo]

Pavel Skripkin <paskripkin@gmail.com> writes:

> Syzbot reported use-after-free Read in ath9k_hif_usb_rx_cb(). 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 save.
>
> Also, I made whitespaces clean ups in *_STAT_* macros definitions
> to make checkpatch.pl happy.

Separate patch for cleanups, please.

> Fixes: fb9987d0f748 ("ath9k_htc: Support for AR9271 chipset.")
> Reported-and-tested-by: syzbot+03110230a11411024147@syzkaller.appspotmail.com
> Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
> ---
>
> Hi, ath9k maintainer/developers!
>
> I know, that you do not like changes, that wasn't tested on real
> hardware. I really don't access to this one, so I'd like you to test it on
> real hardware piece, if you have one. At least, this patch was tested by
> syzbot [1]
>
> [1] https://syzkaller.appspot.com/bug?id=6ead44e37afb6866ac0c7dd121b4ce07cb665f60

syzbot does not equal testing on real hardware. Can someone test or
review this, please?

-- 
https://patchwork.kernel.org/project/linux-wireless/list/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches

Re: [PATCH] net: ath9k: fix use-after-free in ath9k_hif_usb_rx_cb

[Pavel Skripkin]

On 8/4/21 10:48 PM, Pavel Skripkin wrote:
> Syzbot reported use-after-free Read in ath9k_hif_usb_rx_cb(). 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 save.
> 
> Also, I made whitespaces clean ups in *_STAT_* macros definitions
> to make checkpatch.pl happy.
> 
> Fixes: fb9987d0f748 ("ath9k_htc: Support for AR9271 chipset.")
> Reported-and-tested-by: syzbot+03110230a11411024147@syzkaller.appspotmail.com
> Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
> ---
> 
> Hi, ath9k maintainer/developers!
> 
> I know, that you do not like changes, that wasn't tested on real
> hardware. I really don't access to this one, so I'd like you to test it on
> real hardware piece, if you have one. At least, this patch was tested by
> syzbot [1]
> 
> [1] https://syzkaller.appspot.com/bug?id=6ead44e37afb6866ac0c7dd121b4ce07cb665f60
> 
> ---

Btw, this patch also passes this syzbot test

https://syzkaller.appspot.com/bug?id=b8101ffcec107c0567a0cd8acbbacec91e9ee8de


With regards,
Pavel Skripkin

Re: [PATCH] net: ath9k: fix use-after-free in ath9k_hif_usb_rx_cb

[Pavel Skripkin]

On 8/4/21 10:57 PM, Pavel Skripkin wrote:
> On 8/4/21 10:48 PM, Pavel Skripkin wrote:
>> Syzbot reported use-after-free Read in ath9k_hif_usb_rx_cb(). 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 save.
>> 
>> Also, I made whitespaces clean ups in *_STAT_* macros definitions
>> to make checkpatch.pl happy.
>> 
>> Fixes: fb9987d0f748 ("ath9k_htc: Support for AR9271 chipset.")
>> Reported-and-tested-by: syzbot+03110230a11411024147@syzkaller.appspotmail.com
>> Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
>> ---
>> 
>> Hi, ath9k maintainer/developers!
>> 
>> I know, that you do not like changes, that wasn't tested on real
>> hardware. I really don't access to this one, so I'd like you to test it on
>> real hardware piece, if you have one. At least, this patch was tested by
>> syzbot [1]
>> 
>> [1] https://syzkaller.appspot.com/bug?id=6ead44e37afb6866ac0c7dd121b4ce07cb665f60
>> 
>> ---
>>   drivers/net/wireless/ath/ath9k/htc.h          | 11 ++++++-----
>>   drivers/net/wireless/ath/ath9k/htc_drv_init.c |  3 ++-
>>   2 files changed, 8 insertions(+), 6 deletions(-)
>> 
>> diff --git a/drivers/net/wireless/ath/ath9k/htc.h b/drivers/net/wireless/ath/ath9k/htc.h
>> index 0a1634238e67..c16b2a482e83 100644
>> --- a/drivers/net/wireless/ath/ath9k/htc.h
>> +++ b/drivers/net/wireless/ath/ath9k/htc.h
>> @@ -326,11 +326,12 @@ 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 CAB_STAT_INC   priv->debug.tx_stats.cab_queued++
>> +#define __STAT_SAVE(expr)	(hif_dev->htc_handle->drv_priv ? (expr) : 0)
>> +#define TX_STAT_INC(c)		__STAT_SAVE(hif_dev->htc_handle->drv_priv->debug.tx_stats.c++)
>> +#define TX_STAT_ADD(c, a)	__STAT_SAVE(hif_dev->htc_handle->drv_priv->debug.tx_stats.c += a)
>> +#define RX_STAT_INC(c)		__STAT_SAVE(hif_dev->htc_handle->drv_priv->debug.skbrx_stats.c++)
>> +#define RX_STAT_ADD(c, a)	__STAT_SAVE(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:
>> 
> 
> Added missing LKML in CC. Sorry for confusion.
> 
> 
Any chance to review this patch? Thanks




With regards,
Pavel Skripkin

Re: [PATCH] net: ath9k: fix use-after-free in ath9k_hif_usb_rx_cb

[Pavel Skripkin]

On 8/31/21 13:43, Pavel Skripkin wrote:
> On 8/4/21 10:57 PM, Pavel Skripkin wrote:
>> On 8/4/21 10:48 PM, Pavel Skripkin wrote:
>>> Syzbot reported use-after-free Read in ath9k_hif_usb_rx_cb(). 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 save.
>>> 
>>> Also, I made whitespaces clean ups in *_STAT_* macros definitions
>>> to make checkpatch.pl happy.
>>> 
>>> Fixes: fb9987d0f748 ("ath9k_htc: Support for AR9271 chipset.")
>>> Reported-and-tested-by: syzbot+03110230a11411024147@syzkaller.appspotmail.com
>>> Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
>>> ---
>>> 
>>> Hi, ath9k maintainer/developers!
>>> 
>>> I know, that you do not like changes, that wasn't tested on real
>>> hardware. I really don't access to this one, so I'd like you to test it on
>>> real hardware piece, if you have one. At least, this patch was tested by
>>> syzbot [1]
>>> 
>>> [1] https://syzkaller.appspot.com/bug?id=6ead44e37afb6866ac0c7dd121b4ce07cb665f60
>>> 
>>> ---
>>>   drivers/net/wireless/ath/ath9k/htc.h          | 11 ++++++-----
>>>   drivers/net/wireless/ath/ath9k/htc_drv_init.c |  3 ++-
>>>   2 files changed, 8 insertions(+), 6 deletions(-)
>>> 
>>> diff --git a/drivers/net/wireless/ath/ath9k/htc.h b/drivers/net/wireless/ath/ath9k/htc.h
>>> index 0a1634238e67..c16b2a482e83 100644
>>> --- a/drivers/net/wireless/ath/ath9k/htc.h
>>> +++ b/drivers/net/wireless/ath/ath9k/htc.h
>>> @@ -326,11 +326,12 @@ 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 CAB_STAT_INC   priv->debug.tx_stats.cab_queued++
>>> +#define __STAT_SAVE(expr)	(hif_dev->htc_handle->drv_priv ? (expr) : 0)
>>> +#define TX_STAT_INC(c)		__STAT_SAVE(hif_dev->htc_handle->drv_priv->debug.tx_stats.c++)
>>> +#define TX_STAT_ADD(c, a)	__STAT_SAVE(hif_dev->htc_handle->drv_priv->debug.tx_stats.c += a)
>>> +#define RX_STAT_INC(c)		__STAT_SAVE(hif_dev->htc_handle->drv_priv->debug.skbrx_stats.c++)
>>> +#define RX_STAT_ADD(c, a)	__STAT_SAVE(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:
>>> 
>> 
>> Added missing LKML in CC. Sorry for confusion.
>> 
>> 
> Any chance to review this patch? Thanks
> 
> 

gentle ping one more time :) Thanks





With regards,
Pavel Skripkin

[PATCH RESEND] net: ath9k: fix use-after-free in ath9k_hif_usb_rx_cb

[Pavel Skripkin]

Syzbot reported use-after-free Read in ath9k_hif_usb_rx_cb(). 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 save.

Fixes: fb9987d0f748 ("ath9k_htc: Support for AR9271 chipset.")
Reported-and-tested-by: syzbot+03110230a11411024147@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+c6dde1f690b60e0b9fbe@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
---

Why resend?
	No activity on this patch since 8/6/21, Kalle Valo has asked around,
	for review and no one claimed it.

Resend changes:
	1. Rebased on top of v5.15-rc2
	2. Removed clean ups for macros
	3. Added 1 more syzbot tag, since this patch has passed 2 syzbot
	tests

---
 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 0a1634238e67..c8cde2e05d77 100644
--- a/drivers/net/wireless/ath/ath9k/htc.h
+++ b/drivers/net/wireless/ath/ath9k/htc.h
@@ -325,11 +325,11 @@ 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_SAVE(expr) (hif_dev->htc_handle->drv_priv ? (expr) : 0)
+#define TX_STAT_INC(c) __STAT_SAVE(hif_dev->htc_handle->drv_priv->debug.tx_stats.c++)
+#define TX_STAT_ADD(c, a) __STAT_SAVE(hif_dev->htc_handle->drv_priv->debug.tx_stats.c += a)
+#define RX_STAT_INC(c) __STAT_SAVE(hif_dev->htc_handle->drv_priv->debug.skbrx_stats.c++)
+#define RX_STAT_ADD(c, a) __STAT_SAVE(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:
-- 
2.33.0

Re: [PATCH RESEND] net: ath9k: fix use-after-free in ath9k_hif_usb_rx_cb

[Pavel Skripkin]

On 9/22/21 19:42, Pavel Skripkin wrote:
> Syzbot reported use-after-free Read in ath9k_hif_usb_rx_cb(). 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 save.
> 
> Fixes: fb9987d0f748 ("ath9k_htc: Support for AR9271 chipset.")
> Reported-and-tested-by: syzbot+03110230a11411024147@syzkaller.appspotmail.com
> Reported-and-tested-by: syzbot+c6dde1f690b60e0b9fbe@syzkaller.appspotmail.com
> Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
> ---
> 
> Why resend?
> 	No activity on this patch since 8/6/21, Kalle Valo has asked around,
> 	for review and no one claimed it.
> 
> Resend changes:
> 	1. Rebased on top of v5.15-rc2
> 	2. Removed clean ups for macros
> 	3. Added 1 more syzbot tag, since this patch has passed 2 syzbot
> 	tests
> 

Hi, ath9k maintainers!

Does this patch need any further work? I can't see any comments on it 
since 8/6/21 and I can't see it on wireless patchwork.

If this bug is already fixed and I've overlooked a fix commit, please, 
let me know. As I see syzbot hits this bug really often [1]

Thanks


[1] 
https://syzkaller.appspot.com/bug?id=6ead44e37afb6866ac0c7dd121b4ce07cb665f60




With regards,
Pavel Skripkin

Re: [PATCH RESEND] net: ath9k: fix use-after-free in ath9k_hif_usb_rx_cb

[Kalle Valo]

Pavel Skripkin <paskripkin@gmail.com> writes:

> On 9/22/21 19:42, Pavel Skripkin wrote:
>> Syzbot reported use-after-free Read in ath9k_hif_usb_rx_cb(). 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 save.
>>
>> Fixes: fb9987d0f748 ("ath9k_htc: Support for AR9271 chipset.")
>> Reported-and-tested-by: syzbot+03110230a11411024147@syzkaller.appspotmail.com
>> Reported-and-tested-by: syzbot+c6dde1f690b60e0b9fbe@syzkaller.appspotmail.com
>> Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
>> ---
>>
>> Why resend?
>> 	No activity on this patch since 8/6/21, Kalle Valo has asked around,
>> 	for review and no one claimed it.
>>
>> Resend changes:
>> 	1. Rebased on top of v5.15-rc2
>> 	2. Removed clean ups for macros
>> 	3. Added 1 more syzbot tag, since this patch has passed 2 syzbot
>> 	tests
>>
>
> Hi, ath9k maintainers!
>
> Does this patch need any further work? I can't see any comments on it
> since 8/6/21 and I can't see it on wireless patchwork.
>
> If this bug is already fixed and I've overlooked a fix commit, please,
> let me know. As I see syzbot hits this bug really often [1]

See my other mail I just sent about ath9k syzbot patches:

https://lore.kernel.org/linux-wireless/87tuhzhdyq.fsf@codeaurora.org/

In summary: please wait patiently once I'm able to test the syzbot
patches on a real device.

-- 
https://patchwork.kernel.org/project/linux-wireless/list/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches

Re: [PATCH RESEND] net: ath9k: fix use-after-free in ath9k_hif_usb_rx_cb

[Pavel Skripkin]

On 10/2/21 16:11, Kalle Valo wrote:
>> Hi, ath9k maintainers!
>>
>> Does this patch need any further work? I can't see any comments on it
>> since 8/6/21 and I can't see it on wireless patchwork.
>>
>> If this bug is already fixed and I've overlooked a fix commit, please,
>> let me know. As I see syzbot hits this bug really often [1]
> 
> See my other mail I just sent about ath9k syzbot patches:
> 
> https://lore.kernel.org/linux-wireless/87tuhzhdyq.fsf@codeaurora.org/
> 
> In summary: please wait patiently once I'm able to test the syzbot
> patches on a real device.
> 

I see, thank you clarifying the situation. I understand, that 
maintaining ath9k devices alone is not easy task

Thanks again


With regards,
Pavel Skripkin