From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 24889645; Fri, 15 Nov 2024 06:39:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731652790; cv=none; b=kxYXh+k7DHSd5FLGE0PWz4MhA13v4Z+VJLyObmlP6QB/mbyBz165rbj1LXZzXPr/KUbQW1cL8Qg/zKlXXVR+Lnq9pUR5+XDgfz45bzHIkLBuxYnY8/QAjiTnRzxs5iYRVYyD7+usoJnWz3DU2/oARgNGzjRfZFnR8Cf0a8EPYrQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731652790; c=relaxed/simple; bh=JOs6rovnBUfsTAT8fo/tqdat6uboVw9PTP2Dho+KFVw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=NK9FtzYpo123q9UjxD6x1D3RiTAEOBr06isxIm2KbLX9eYTomprDZQWSoYMC13vyz6S8gI9rGzPzaeodMC2XEyGyBaHrMXsHUJJvKFzbyVq62Ta5qjJVIlc1YNRwtDfDmmmHN8lQFd82G8acY9HIxnK6O0sWU3Ui2V3yuV63DKc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=qrcryjoQ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="qrcryjoQ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 87149C4CED0; Fri, 15 Nov 2024 06:39:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1731652790; bh=JOs6rovnBUfsTAT8fo/tqdat6uboVw9PTP2Dho+KFVw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qrcryjoQElcdvi5NLtxdhOg+AGsBgCw2oZ54Ym8q8EQ7TyurHtbrZMVYFdmi8Tjga F7Opc2ICVeTLjMwZaxihcDRnvS11AssYEQWcE7yHKXMRLcHXgxCH4/CNWDrajqLvB7 dg2G25BB1pTuNr96OjisAx+klGo8Wgy+BYZK1x5I= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Mauro Carvalho Chehab Subject: [PATCH 4.19 16/52] media: cx24116: prevent overflows on SNR calculus Date: Fri, 15 Nov 2024 07:37:29 +0100 Message-ID: <20241115063723.442510487@linuxfoundation.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241115063722.845867306@linuxfoundation.org> References: <20241115063722.845867306@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mauro Carvalho Chehab commit 576a307a7650bd544fbb24df801b9b7863b85e2f upstream. as reported by Coverity, if reading SNR registers fail, a negative number will be returned, causing an underflow when reading SNR registers. Prevent that. Fixes: 8953db793d5b ("V4L/DVB (9178): cx24116: Add module parameter to return SNR as ESNO.") Cc: stable@vger.kernel.org Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman --- drivers/media/dvb-frontends/cx24116.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/drivers/media/dvb-frontends/cx24116.c +++ b/drivers/media/dvb-frontends/cx24116.c @@ -753,6 +753,7 @@ static int cx24116_read_snr_pct(struct d { struct cx24116_state *state = fe->demodulator_priv; u8 snr_reading; + int ret; static const u32 snr_tab[] = { /* 10 x Table (rounded up) */ 0x00000, 0x0199A, 0x03333, 0x04ccD, 0x06667, 0x08000, 0x0999A, 0x0b333, 0x0cccD, 0x0e667, @@ -761,7 +762,11 @@ static int cx24116_read_snr_pct(struct d dprintk("%s()\n", __func__); - snr_reading = cx24116_readreg(state, CX24116_REG_QUALITY0); + ret = cx24116_readreg(state, CX24116_REG_QUALITY0); + if (ret < 0) + return ret; + + snr_reading = ret; if (snr_reading >= 0xa0 /* 100% */) *snr = 0xffff;