Re: [PATCH 5.4 regression fix] brcmfmac: Fix brcmf_cfg80211_get_channel returning uninitialized fields

[Kalle Valo <kvalo@codeaurora.org>]

Hans de Goede <hdegoede@redhat.com> writes:

> With the new edmg support struct cfg80211_chan_def has been extended
> with a number of new members. brcmf_cfg80211_get_channel() was not setting
> (clearing) these causing the cfg80211_edmg_chandef_valid() check in
> cfg80211_chandef_valid() to fail. Triggering a WARN_ON and, worse, causing
> brcmfmac based wifi cards to not work.
>
> This commit fixes this by clearing the entire passed struct to 0 before
> setting the members used by the brcmfmac code. This solution also makes
> sure that this problem will not repeat itself in the future if further
> members are added to the struct.
>
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
>  drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
> index e3ebb7abbdae..480c05f66ebd 100644
> --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
> @@ -5041,10 +5041,10 @@ static int brcmf_cfg80211_get_channel(struct wiphy *wiphy,
>  	}
>  
>  	freq = ieee80211_channel_to_frequency(ch.control_ch_num, band);
> +	memset(chandef, 0, sizeof(*chandef));
>  	chandef->chan = ieee80211_get_channel(wiphy, freq);
>  	chandef->width = width;
>  	chandef->center_freq1 = ieee80211_channel_to_frequency(ch.chnum, band);
> -	chandef->center_freq2 = 0;
>  
>  	return 0;
>  }

Is this a separate issue from the cfg80211 fix:

cfg80211: initialize on-stack chandefs

https://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211.git/commit/?id=f43e5210c739fe76a4b0ed851559d6902f20ceb1

-- 
Kalle Valo