Re: [PATCH] wcn36xx: Initialize channel to NULL inside wcn36xx_change_opchannel()

From: Kalle Valo
Date: Mon Feb 21 2022 - 05:04:35 EST


Souptick Joarder <jrdr.linux@xxxxxxxxx> writes:

> From: "Souptick Joarder (HPE)" <jrdr.linux@xxxxxxxxx>
>
> Kernel test robot reported below warning ->
> drivers/net/wireless/ath/wcn36xx/main.c:409:7: warning: Branch
> condition evaluates to a garbage value
> [clang-analyzer-core.uninitialized.Branch]
>
> Also code walk indicates, if channel is not found in first band,
> it will break the loop and instead of exit it will go ahead and
> assign a garbage value in wcn->channel which looks like a bug.
>
> Initialize channel with NULL should avoid this issue.
>
> Fixes: d6f2746691cb ("wcn36xx: Track the band and channel we are tuned to")
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Signed-off-by: Souptick Joarder (HPE) <jrdr.linux@xxxxxxxxx>
> ---
> drivers/net/wireless/ath/wcn36xx/main.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/wireless/ath/wcn36xx/main.c b/drivers/net/wireless/ath/wcn36xx/main.c
> index 75661d449712..1a06eff07107 100644
> --- a/drivers/net/wireless/ath/wcn36xx/main.c
> +++ b/drivers/net/wireless/ath/wcn36xx/main.c
> @@ -394,7 +394,7 @@ static void wcn36xx_change_opchannel(struct wcn36xx *wcn, int ch)
> struct ieee80211_vif *vif = NULL;
> struct wcn36xx_vif *tmp;
> struct ieee80211_supported_band *band;
> - struct ieee80211_channel *channel;
> + struct ieee80211_channel *channel = NULL;
> unsigned long flags;
> int i, j;

I have already applied an identical patch from Dan:

https://git.kernel.org/pub/scm/linux/kernel/git/kvalo/ath.git/commit/?h=ath-next&id=11e41e2929378df945bf50b95409d93059ad4507

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