Author: Mohammed Shafi Shajakhan <[email protected]>
Date: Thu Apr 27 12:45:38 2017 +0530
mac80211: Fix possible sband related NULL pointer de-reference
Existing API 'ieee80211_get_sdata_band' returns default 2 GHz band even
if the channel context configuration is NULL. This crashes for chipsets
which support 5 Ghz alone when it tries to access members of 'sband'.
Channel context configuration can be NULL in multivif case and when
channel switch is in progress (or) when it fails. Fix this by replacing
the API 'ieee80211_get_sdata_band' with 'ieee80211_get_sband' which
returns a NULL pointer for sband when the channel configuration is NULL.
...
This commit appears to break sta_set_rate_info_tx on drivers that are not using chantx,
because it calls ieee80211_get_sband, which does a WARN_ON when there is no chantx.
Any idea how to make this work for chandef drivers?
Thanks,
Ben
--
Ben Greear <[email protected]>
Candela Technologies Inc http://www.candelatech.com
On 11/17/2017 02:30 PM, Ben Greear wrote:
> Author: Mohammed Shafi Shajakhan <[email protected]>
> Date: Thu Apr 27 12:45:38 2017 +0530
>
> mac80211: Fix possible sband related NULL pointer de-reference
>
> Existing API 'ieee80211_get_sdata_band' returns default 2 GHz band even
> if the channel context configuration is NULL. This crashes for chipsets
> which support 5 Ghz alone when it tries to access members of 'sband'.
> Channel context configuration can be NULL in multivif case and when
> channel switch is in progress (or) when it fails. Fix this by replacing
> the API 'ieee80211_get_sdata_band' with 'ieee80211_get_sband' which
> returns a NULL pointer for sband when the channel configuration is NULL.
>
> ...
>
> This commit appears to break sta_set_rate_info_tx on drivers that are not using chantx,
> because it calls ieee80211_get_sband, which does a WARN_ON when there is no chantx.
>
> Any idea how to make this work for chandef drivers?
Maybe there are other issues in my case. I'll test out a patch to make it WARN_ON_ONCE
and submit once I get some other problems ironed out.
Thanks,
Ben
--
Ben Greear <[email protected]>
Candela Technologies Inc http://www.candelatech.com