Re: [PATCH v2] wireless/nl80211.c: fix uninitialized variable

From: Greg KH
Date: Tue Mar 30 2021 - 13:15:57 EST


On Tue, Mar 30, 2021 at 06:37:05PM +0200, Alaa Emad wrote:
> This change fix KMSAN uninit-value in net/wireless/nl80211.c:225 , That
> because of `fixedlen` variable uninitialized,So I initialized it by zero.
>
> Reported-by: syzbot+72b99dcf4607e8c770f3@xxxxxxxxxxxxxxxxxxxxxxxxx
> Signed-off-by: Alaa Emad <alaaemadhossney.ae@xxxxxxxxx>
> ---
> Changes in v2:
> - Make the commit message more clearer.
> ---
> net/wireless/nl80211.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
> index 775d0c4d86c3..b87ab67ad33d 100644
> --- a/net/wireless/nl80211.c
> +++ b/net/wireless/nl80211.c
> @@ -210,7 +210,7 @@ static int validate_beacon_head(const struct nlattr *attr,
> const struct element *elem;
> const struct ieee80211_mgmt *mgmt = (void *)data;
> bool s1g_bcn = ieee80211_is_s1g_beacon(mgmt->frame_control);
> - unsigned int fixedlen, hdrlen;
> + unsigned int fixedlen = 0 , hdrlen;

Please always use scripts/checkpatch.pl before sending out patches. It
would have pointed out that this line is incorrect and needs to be fixed
up :(

thanks,

greg k-h