* mac80211 : fix unaligned rx skb
@ 2009-06-04 20:16 matthieu castet
2009-06-04 20:53 ` Luis R. Rodriguez
0 siblings, 1 reply; 8+ messages in thread
From: matthieu castet @ 2009-06-04 20:16 UTC (permalink / raw)
To: linux-wireless
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mac80211 is checking is the skb is aligned on 32 bit boundary.
But it is checking against ethernet header, whereas Linux expect IP
header aligned.
And ethernet ether size is 6*2+2=14, so aligning ethernet header make IP header unaligned.
Signed-off-by: Matthieu CASTET <castet.matthieu@free.fr>
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 9776f73..0845fb3 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -1397,7 +1397,7 @@ ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
* mac80211. That also explains the __skb_push()
* below.
*/
- align = (unsigned long)skb->data & 3;
+ align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
if (align) {
if (WARN_ON(skb_headroom(skb) < 3)) {
dev_kfree_skb(skb);
^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: mac80211 : fix unaligned rx skb
2009-06-04 20:16 mac80211 : fix unaligned rx skb matthieu castet
@ 2009-06-04 20:53 ` Luis R. Rodriguez
2009-06-04 21:16 ` Georgy Berdyshev
0 siblings, 1 reply; 8+ messages in thread
From: Luis R. Rodriguez @ 2009-06-04 20:53 UTC (permalink / raw)
To: matthieu castet; +Cc: linux-wireless
On Thu, Jun 4, 2009 at 1:16 PM, matthieu castet <castet.matthieu@free.fr> wrote:
>
This is all I see, can you resend with patch inline?
Luis
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: mac80211 : fix unaligned rx skb
2009-06-04 20:53 ` Luis R. Rodriguez
@ 2009-06-04 21:16 ` Georgy Berdyshev
2009-06-04 21:40 ` Michael Buesch
0 siblings, 1 reply; 8+ messages in thread
From: Georgy Berdyshev @ 2009-06-04 21:16 UTC (permalink / raw)
To: Luis R. Rodriguez; +Cc: matthieu castet, linux-wireless
Hi,
that's the inline version:
-------
mac80211 is checking is the skb is aligned on 32 bit boundary.
But it is checking against ethernet header, whereas Linux expect IP
header aligned.
And ethernet ether size is 6*2+2=14, so aligning ethernet header make
IP header unaligned.
Signed-off-by: Matthieu CASTET <castet.matthieu@free.fr>
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 9776f73..0845fb3 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -1397,7 +1397,7 @@ ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
* mac80211. That also explains the __skb_push()
* below.
*/
- align = (unsigned long)skb->data & 3;
+ align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
if (align) {
if (WARN_ON(skb_headroom(skb) < 3)) {
dev_kfree_skb(skb);
------------
On Thu, Jun 4, 2009 at 5:53 PM, Luis R. Rodriguez <mcgrof@gmail.com> wrote:
> On Thu, Jun 4, 2009 at 1:16 PM, matthieu castet <castet.matthieu@free.fr> wrote:
>>
>
> This is all I see, can you resend with patch inline?
>
> Luis
> --
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>
--
Georgy Berdyshev
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^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: mac80211 : fix unaligned rx skb
2009-06-04 21:16 ` Georgy Berdyshev
@ 2009-06-04 21:40 ` Michael Buesch
2009-06-05 5:57 ` matthieu castet
0 siblings, 1 reply; 8+ messages in thread
From: Michael Buesch @ 2009-06-04 21:40 UTC (permalink / raw)
To: Georgy Berdyshev; +Cc: Luis R. Rodriguez, matthieu castet, linux-wireless
On Thursday 04 June 2009 23:16:13 Georgy Berdyshev wrote:
> Hi,
>
> that's the inline version:
> -------
> mac80211 is checking is the skb is aligned on 32 bit boundary.
> But it is checking against ethernet header, whereas Linux expect IP
> header aligned.
> And ethernet ether size is 6*2+2=14, so aligning ethernet header make
> IP header unaligned.
>
> Signed-off-by: Matthieu CASTET <castet.matthieu@free.fr>
> diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
> index 9776f73..0845fb3 100644
> --- a/net/mac80211/rx.c
> +++ b/net/mac80211/rx.c
> @@ -1397,7 +1397,7 @@ ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
> * mac80211. That also explains the __skb_push()
> * below.
> */
> - align = (unsigned long)skb->data & 3;
> + align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
> if (align) {
> if (WARN_ON(skb_headroom(skb) < 3)) {
> dev_kfree_skb(skb);
Uhm, can you give a more verbose explanation? Without that I'd say this patch is plain wrong.
What the hell does struct ethhdr have to do with wireless?
This is not ethernet. It's 802.11. There is no such thing as an ethernet header in a 802.11 packet.
--
Greetings, Michael.
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: mac80211 : fix unaligned rx skb
2009-06-04 21:40 ` Michael Buesch
@ 2009-06-05 5:57 ` matthieu castet
2009-06-07 9:24 ` matthieu castet
0 siblings, 1 reply; 8+ messages in thread
From: matthieu castet @ 2009-06-05 5:57 UTC (permalink / raw)
To: Michael Buesch; +Cc: Georgy Berdyshev, Luis R. Rodriguez, linux-wireless
Michael Buesch wrote:
> On Thursday 04 June 2009 23:16:13 Georgy Berdyshev wrote:
>> Hi,
>>
>> that's the inline version:
>> -------
>> mac80211 is checking is the skb is aligned on 32 bit boundary.
>> But it is checking against ethernet header, whereas Linux expect IP
>> header aligned.
>> And ethernet ether size is 6*2+2=14, so aligning ethernet header make
>> IP header unaligned.
>>
>> Signed-off-by: Matthieu CASTET <castet.matthieu@free.fr>
>> diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
>> index 9776f73..0845fb3 100644
>> --- a/net/mac80211/rx.c
>> +++ b/net/mac80211/rx.c
>> @@ -1397,7 +1397,7 @@ ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
>> * mac80211. That also explains the __skb_push()
>> * below.
>> */
>> - align = (unsigned long)skb->data & 3;
>> + align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
>> if (align) {
>> if (WARN_ON(skb_headroom(skb) < 3)) {
>> dev_kfree_skb(skb);
>
> Uhm, can you give a more verbose explanation? Without that I'd say this patch is plain wrong.
> What the hell does struct ethhdr have to do with wireless?
> This is not ethernet. It's 802.11. There is no such thing as an
> ethernet header in a 802.11 packet.
>
Where are in ieee80211_deliver_skb that is called after
ieee80211_data_to_8023. So it is not 802.11.
Matthieu
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: mac80211 : fix unaligned rx skb
2009-06-05 5:57 ` matthieu castet
@ 2009-06-07 9:24 ` matthieu castet
2009-06-07 9:26 ` Michael Buesch
0 siblings, 1 reply; 8+ messages in thread
From: matthieu castet @ 2009-06-07 9:24 UTC (permalink / raw)
To: Michael Buesch; +Cc: Georgy Berdyshev, Luis R. Rodriguez, linux-wireless
matthieu castet wrote:
> Michael Buesch wrote:
>> On Thursday 04 June 2009 23:16:13 Georgy Berdyshev wrote:
>>> Hi,
>>>
>>> that's the inline version:
>>> -------
>>> mac80211 is checking is the skb is aligned on 32 bit boundary.
>>> But it is checking against ethernet header, whereas Linux expect IP
>>> header aligned.
>>> And ethernet ether size is 6*2+2=14, so aligning ethernet header make
>>> IP header unaligned.
>>>
>>> Signed-off-by: Matthieu CASTET <castet.matthieu@free.fr>
>>> diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
>>> index 9776f73..0845fb3 100644
>>> --- a/net/mac80211/rx.c
>>> +++ b/net/mac80211/rx.c
>>> @@ -1397,7 +1397,7 @@ ieee80211_deliver_skb(struct ieee80211_rx_data
>>> *rx)
>>> * mac80211. That also explains the __skb_push()
>>> * below.
>>> */
>>> - align = (unsigned long)skb->data & 3;
>>> + align = ((unsigned long)(skb->data + sizeof(struct ethhdr)))
>>> & 3;
>>> if (align) {
>>> if (WARN_ON(skb_headroom(skb) < 3)) {
>>> dev_kfree_skb(skb);
>>
>> Uhm, can you give a more verbose explanation? Without that I'd say
>> this patch is plain wrong.
>> What the hell does struct ethhdr have to do with wireless?
> > This is not ethernet. It's 802.11. There is no such thing as an
> > ethernet header in a 802.11 packet.
> >
> Where are in ieee80211_deliver_skb that is called after
> ieee80211_data_to_8023. So it is not 802.11.
>
Do you want more explanation ?
Matthieu
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: mac80211 : fix unaligned rx skb
2009-06-07 9:24 ` matthieu castet
@ 2009-06-07 9:26 ` Michael Buesch
2009-06-07 15:18 ` John W. Linville
0 siblings, 1 reply; 8+ messages in thread
From: Michael Buesch @ 2009-06-07 9:26 UTC (permalink / raw)
To: matthieu castet; +Cc: Georgy Berdyshev, Luis R. Rodriguez, linux-wireless
On Sunday 07 June 2009 11:24:48 matthieu castet wrote:
> matthieu castet wrote:
> > Michael Buesch wrote:
> >> On Thursday 04 June 2009 23:16:13 Georgy Berdyshev wrote:
> >>> Hi,
> >>>
> >>> that's the inline version:
> >>> -------
> >>> mac80211 is checking is the skb is aligned on 32 bit boundary.
> >>> But it is checking against ethernet header, whereas Linux expect IP
> >>> header aligned.
> >>> And ethernet ether size is 6*2+2=14, so aligning ethernet header make
> >>> IP header unaligned.
> >>>
> >>> Signed-off-by: Matthieu CASTET <castet.matthieu@free.fr>
> >>> diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
> >>> index 9776f73..0845fb3 100644
> >>> --- a/net/mac80211/rx.c
> >>> +++ b/net/mac80211/rx.c
> >>> @@ -1397,7 +1397,7 @@ ieee80211_deliver_skb(struct ieee80211_rx_data
> >>> *rx)
> >>> * mac80211. That also explains the __skb_push()
> >>> * below.
> >>> */
> >>> - align = (unsigned long)skb->data & 3;
> >>> + align = ((unsigned long)(skb->data + sizeof(struct ethhdr)))
> >>> & 3;
> >>> if (align) {
> >>> if (WARN_ON(skb_headroom(skb) < 3)) {
> >>> dev_kfree_skb(skb);
> >>
> >> Uhm, can you give a more verbose explanation? Without that I'd say
> >> this patch is plain wrong.
> >> What the hell does struct ethhdr have to do with wireless?
> > > This is not ethernet. It's 802.11. There is no such thing as an
> > > ethernet header in a 802.11 packet.
> > >
> > Where are in ieee80211_deliver_skb that is called after
> > ieee80211_data_to_8023. So it is not 802.11.
> >
> Do you want more explanation ?
No reply always means "ok" on this list ;)
--
Greetings, Michael.
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: mac80211 : fix unaligned rx skb
2009-06-07 9:26 ` Michael Buesch
@ 2009-06-07 15:18 ` John W. Linville
0 siblings, 0 replies; 8+ messages in thread
From: John W. Linville @ 2009-06-07 15:18 UTC (permalink / raw)
To: Michael Buesch
Cc: matthieu castet, Georgy Berdyshev, Luis R. Rodriguez,
linux-wireless, johannes
On Sun, Jun 07, 2009 at 11:26:22AM +0200, Michael Buesch wrote:
> On Sunday 07 June 2009 11:24:48 matthieu castet wrote:
> > matthieu castet wrote:
> > > Where are in ieee80211_deliver_skb that is called after
> > > ieee80211_data_to_8023. So it is not 802.11.
> > >
> > Do you want more explanation ?
>
> No reply always means "ok" on this list ;)
Probably true...however, I was hoping to see an ACK from Johannes...
John
--
John W. Linville Someday the world will need a hero, and you
linville@tuxdriver.com might be all we have. Be ready.
^ permalink raw reply [flat|nested] 8+ messages in thread
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2009-06-04 20:16 mac80211 : fix unaligned rx skb matthieu castet
2009-06-04 20:53 ` Luis R. Rodriguez
2009-06-04 21:16 ` Georgy Berdyshev
2009-06-04 21:40 ` Michael Buesch
2009-06-05 5:57 ` matthieu castet
2009-06-07 9:24 ` matthieu castet
2009-06-07 9:26 ` Michael Buesch
2009-06-07 15:18 ` John W. Linville
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