From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AG47ELvf0A7JoCAN5u3IBNf+LIlukgAQyULIcDqTyFM90hQzm9V8SXDVCu0ycCcPPk86FJhdmFws ARC-Seal: i=1; a=rsa-sha256; t=1520723185; cv=none; d=google.com; s=arc-20160816; b=EiB9geFvS2wepgBi1GxSsmHhfmmJ/F6wvEQGWBSsBZuPCi0WRDZmay8DgVFJ/MCwY+ fRGDhdwgWd949kp2ASbes0iZTwpumQ9/goWO3Qx2QtLpUUxD4owGc1fSq9/I7Kq72x2B KR7pDDfFKSl/SgedwP794W7Vtm3Pc+a06Ww40v3xUQ4vWH2E9i15bhVUWhpYpuSR1wbn CemdIiYDvj/q9zRTWolY5Kqmjq34M7kgIEZyE32ba3XXLsJcjJCUeJ3UJm9aHxgNZvVS Vw2/2JTr+RpVktriGram0EHVlMDT7IYNJDA3bRmCCGgOAjkGB15LnqHka8aqq8TsI3ma Uqxw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-transfer-encoding:in-reply-to:mime-version:user-agent:date :message-id:from:cc:references:to:subject:dkim-signature :delivered-to:list-id:list-subscribe:list-unsubscribe:list-help :list-post:precedence:mailing-list:arc-authentication-results; bh=DK9VLqTRRWq2hN9EglAZso4hp+E8gUFJlhzN4IGGzSk=; b=nk/An5qSKltf7TdBVCjpbsAw5rdhYdae/Sb5BMgOdUJS/SKq5/nX7UOxpuxzo2WtGz MQ3AODgrXhuwwVsiDGSsPrIk7AFla9i8REwzGM3D+0vmlEfn+X6Prlt7EpbuH9UuKU45 QBHTtkFNP1cTiMbGprz7fg4nnTMjUwDJxy11LfF5JSzZSG/EByXiVZ2sXcNZnvwMtOaL Hcj0YamDC8i85SE8vjHl+71maKfKg3glS8I1oSghq5xwXWATfoLZKjD6X6jm9C/FdCTW nG20HIQuUSG2xbBATs/MU9IiRacX7zS5oiAow668/UPym1Ql9eddxHiflV6h10Cz4oq9 6wUw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@broadcom.com header.s=google header.b=LEV3B5Uq; spf=pass (google.com: domain of kernel-hardening-return-12388-gregkh=linuxfoundation.org@lists.openwall.com designates 195.42.179.200 as permitted sender) smtp.mailfrom=kernel-hardening-return-12388-gregkh=linuxfoundation.org@lists.openwall.com; dmarc=pass (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=broadcom.com Authentication-Results: mx.google.com; dkim=pass header.i=@broadcom.com header.s=google header.b=LEV3B5Uq; spf=pass (google.com: domain of kernel-hardening-return-12388-gregkh=linuxfoundation.org@lists.openwall.com designates 195.42.179.200 as permitted sender) smtp.mailfrom=kernel-hardening-return-12388-gregkh=linuxfoundation.org@lists.openwall.com; dmarc=pass (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=broadcom.com Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm List-Post: List-Help: List-Unsubscribe: List-Subscribe: Subject: Re: [PATCH] drivers: net: wireless: ath: ath9: dfs: remove VLA usage To: Andreas Christoforou , keescook@chromium.org References: <1520598613-3641-1-git-send-email-andreaschristofo@gmail.com> Cc: kernel-hardening@lists.openwall.com, QCA ath9k Development , Kalle Valo , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org From: Arend van Spriel Message-ID: <5AA464DE.90100@broadcom.com> Date: Sun, 11 Mar 2018 00:06:06 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.5.0 MIME-Version: 1.0 In-Reply-To: <1520598613-3641-1-git-send-email-andreaschristofo@gmail.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1594463764603415966?= X-GMAIL-MSGID: =?utf-8?q?1594593834672771810?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: On 3/9/2018 1:30 PM, Andreas Christoforou wrote: > The kernel would like to have all stack VLA usage removed. I think there was a remark made earlier to give more explanation here. It should explain why we want "VLA on stack" removed. > Signed-off-by: Andreas Christoforou > --- > drivers/net/wireless/ath/ath9k/dfs.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/net/wireless/ath/ath9k/dfs.c b/drivers/net/wireless/ath/ath9k/dfs.c > index 6fee9a4..cfb0f84 100644 > --- a/drivers/net/wireless/ath/ath9k/dfs.c > +++ b/drivers/net/wireless/ath/ath9k/dfs.c > @@ -41,7 +41,6 @@ static const int BIN_DELTA_MAX = 10; > > /* we need at least 3 deltas / 4 samples for a reliable chirp detection */ > #define NUM_DIFFS 3 > -static const int FFT_NUM_SAMPLES = (NUM_DIFFS + 1); > > /* Threshold for difference of delta peaks */ > static const int MAX_DIFF = 2; > @@ -101,7 +100,7 @@ static bool ath9k_check_chirping(struct ath_softc *sc, u8 *data, > int datalen, bool is_ctl, bool is_ext) > { > int i; > - int max_bin[FFT_NUM_SAMPLES]; > + int max_bin[NUM_DIFFS + 1]; Just wondering. Is this actually a VLA. FFT_NUM_SAMPLES was static const so not really going to show a lot of variation. This array will always have the same size on the stack. Regards, Arend