From: Helmut Schaa <[email protected]>
ath9k_htc adds padding between the 802.11 header and the payload during
TX by moving the header. When handing the frame back to mac80211 for TX
status handling the header is not moved back into its original position.
This can result in a too small skb headroom when entering ath9k_htc
again (due to a soft retransmission for example) causing an
skb_under_panic oops.
Fix this by moving the 802.11 header back into its original position
before returning the frame to mac80211 as other drivers like rt2x00
or ath5k do.
Reported-by: Marc Kleine-Budde <[email protected]>
Signed-off-by: Helmut Schaa <[email protected]>
Tested-by: Marc Kleine-Budde <[email protected]>
Signed-off-by: Marc Kleine-Budde <[email protected]>
---
Hello Helmut,
I've change the patch a bit, I've used ieee80211_get_hdrlen_from_skb() instead
of open coding it.
Tested in ARMv5 with USB device
"ID 0cf3:7015 Atheros Communications, Inc. TP-Link TL-WN821N v3 802.11n [Atheros AR7010+AR9287]"
for four weeks. Without that patch the kernel oopes after about one week.
I think this is a candidate for stable, can you add stable to Cc?
regards,
Marc
changes since v1:
- use ieee80211_get_hdrlen_from_skb() instead of open coding it
drivers/net/wireless/ath/ath9k/htc_drv_txrx.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c b/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c
index e602c95..c028df7 100644
--- a/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c
+++ b/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c
@@ -448,6 +448,7 @@ static void ath9k_htc_tx_process(struct ath9k_htc_priv *priv,
struct ieee80211_conf *cur_conf = &priv->hw->conf;
bool txok;
int slot;
+ int hdrlen, padsize;
slot = strip_drv_header(priv, skb);
if (slot < 0) {
@@ -504,6 +505,15 @@ send_mac80211:
ath9k_htc_tx_clear_slot(priv, slot);
+ /* Remove padding before handing frame back to mac80211 */
+ hdrlen = ieee80211_get_hdrlen_from_skb(skb);
+
+ padsize = hdrlen & 3;
+ if (padsize && skb->len > hdrlen + padsize) {
+ memmove(skb->data + padsize, skb->data, hdrlen);
+ skb_pull(skb, padsize);
+ }
+
/* Send status to mac80211 */
ieee80211_tx_status(priv->hw, skb);
}
--
1.8.3.1
On 08/16/2013 09:39 PM, Marc Kleine-Budde wrote:
> From: Helmut Schaa <[email protected]>
>
> ath9k_htc adds padding between the 802.11 header and the payload during
> TX by moving the header. When handing the frame back to mac80211 for TX
> status handling the header is not moved back into its original position.
> This can result in a too small skb headroom when entering ath9k_htc
> again (due to a soft retransmission for example) causing an
> skb_under_panic oops.
>
> Fix this by moving the 802.11 header back into its original position
> before returning the frame to mac80211 as other drivers like rt2x00
> or ath5k do.
>
> Reported-by: Marc Kleine-Budde <[email protected]>
> Signed-off-by: Helmut Schaa <[email protected]>
> Tested-by: Marc Kleine-Budde <[email protected]>
> Signed-off-by: Marc Kleine-Budde <[email protected]>
> ---
> Hello Helmut,
>
> I've change the patch a bit, I've used ieee80211_get_hdrlen_from_skb() instead
> of open coding it.
>
> Tested in ARMv5 with USB device
> "ID 0cf3:7015 Atheros Communications, Inc. TP-Link TL-WN821N v3 802.11n [Atheros AR7010+AR9287]"
> for four weeks. Without that patch the kernel oopes after about one week.
>
> I think this is a candidate for stable, can you add stable to Cc?
ping
Marc
Hi John, Hi Marc,
On Tue, Aug 20, 2013 at 11:01 AM, Marc Kleine-Budde <[email protected]> wrote:
> On 08/16/2013 09:39 PM, Marc Kleine-Budde wrote:
>> From: Helmut Schaa <[email protected]>
>>
>> ath9k_htc adds padding between the 802.11 header and the payload during
>> TX by moving the header. When handing the frame back to mac80211 for TX
>> status handling the header is not moved back into its original position.
>> This can result in a too small skb headroom when entering ath9k_htc
>> again (due to a soft retransmission for example) causing an
>> skb_under_panic oops.
>>
>> Fix this by moving the 802.11 header back into its original position
>> before returning the frame to mac80211 as other drivers like rt2x00
>> or ath5k do.
>>
>> Reported-by: Marc Kleine-Budde <[email protected]>
>> Signed-off-by: Helmut Schaa <[email protected]>
>> Tested-by: Marc Kleine-Budde <[email protected]>
>> Signed-off-by: Marc Kleine-Budde <[email protected]>
>> ---
>> Hello Helmut,
>>
>> I've change the patch a bit, I've used ieee80211_get_hdrlen_from_skb() instead
>> of open coding it.
>>
>> Tested in ARMv5 with USB device
>> "ID 0cf3:7015 Atheros Communications, Inc. TP-Link TL-WN821N v3 802.11n [Atheros AR7010+AR9287]"
>> for four weeks. Without that patch the kernel oopes after about one week.
>>
>> I think this is a candidate for stable, can you add stable to Cc?
>
> ping
Sorry, completely forgot about this patch. You're right, this is
indeed a stable candidate.
John, could you please add "Cc: [email protected]" when applying
this to your tree?
Thanks,
Helmut
On Fri, Aug 16, 2013 at 9:39 PM, Marc Kleine-Budde <[email protected]> wrote:
> Tested in ARMv5 with USB device
> "ID 0cf3:7015 Atheros Communications, Inc. TP-Link TL-WN821N v3 802.11n [Atheros AR7010+AR9287]"
> for four weeks. Without that patch the kernel oopes after about one week.
Thanks for testing by the way!
Helmut