From nobody Thu Dec 18 13:14:08 2025 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 08F151F3FEE for ; Mon, 24 Mar 2025 21:56:29 +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=1742853389; cv=none; b=hk5oYsbqjWKBdQh71muEIxbDSaQwf18W4yG057Nj7RvRkkp5TX1He6F/ldn/FWdBP5Xx78j/QqBWGPdLKBnjcZPzVSv7aZ3upT769ZVvecsstBSl7ve9Qg/5BI+lP0fgRi0yy4sc45AiuYqJBr/Xr07lYHXn7s5lMnxT+2teI6k= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742853389; c=relaxed/simple; bh=SMqJ/mdxDUlaT7sCHuMQcldNMFe2OQbR1k57sPHhsYw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=sUGIGPS8CPJU0TKT7KJvisIJDBxW+fk8Yur04o9G9KOR8czC/N++M1Lk15JN+i8ApICtZqzptTA6nu04kwwG9IS/n6RQnSzEwSTwJ7MNFGcnFTAjm8YIAW8gJ+OMjDKMfel/v899uPX04kO0PElQVoyY2Xicd7MABirr9CSPhww= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=T5J3o8rG; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="T5J3o8rG" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 88179C4CEE4; Mon, 24 Mar 2025 21:56:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1742853388; bh=SMqJ/mdxDUlaT7sCHuMQcldNMFe2OQbR1k57sPHhsYw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=T5J3o8rGqRFbhzpVB+HSQSUCd+LB8+GKgriCJ76BHS8VJyVHtfzRGlmom1lo+Cv3q RYVvKq/Pm5hBYgYRyIYna+qnuxgXbVVL5+5/mVXWvnesZdHRAxOMxuv+Au8js02H3f u2AVOoWIsvEugOE1Lt4Nd4zH8jL06Xvi5kD87dHbCHlrskBZhinxkhxUBPSMmLHqn3 +9Lnp1xAeX1nD01n83RFuNR4VBkcicqPlvLA62EYaEflmT1f0FdcTfN06kC6LoFqDg 0RA1r7PYP+Xqg00hYtBavMcWVM0vAmyAUG+h+AgXEKa5CHj5TUtUqx32FUCjtF9i4+ biNIBhtBFYmmQ== From: Josh Poimboeuf To: x86@kernel.org Cc: linux-kernel@vger.kernel.org, Peter Zijlstra , Ingo Molnar , Miroslav Benes , Brendan Jackman , Nathan Chancellor , Mauro Carvalho Chehab , kernel test robot Subject: [PATCH 16/22] media: dib8000: Prevent divide-by-zero in dib8000_set_dds() Date: Mon, 24 Mar 2025 14:56:06 -0700 Message-ID: X-Mailer: git-send-email 2.48.1 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" If dib8000_set_dds()'s call to dib8000_read32() returns zero, the result is a divide-by-zero. Prevent that from happening. Fixes the following warning with an UBSAN kernel: drivers/media/dvb-frontends/dib8000.o: warning: objtool: dib8000_tune() f= alls through to next function dib8096p_cfg_DibRx() Cc: Mauro Carvalho Chehab Fixes: 173a64cb3fcf ("[media] dib8000: enhancement") Reported-by: kernel test robot Closes: https://lore.kernel.org/r/202503210602.fvH5DO1i-lkp@intel.com/ Signed-off-by: Josh Poimboeuf --- drivers/media/dvb-frontends/dib8000.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/media/dvb-frontends/dib8000.c b/drivers/media/dvb-fron= tends/dib8000.c index 2f5165918163..cfe59c3255f7 100644 --- a/drivers/media/dvb-frontends/dib8000.c +++ b/drivers/media/dvb-frontends/dib8000.c @@ -2701,8 +2701,11 @@ static void dib8000_set_dds(struct dib8000_state *st= ate, s32 offset_khz) u8 ratio; =20 if (state->revision =3D=3D 0x8090) { + u32 internal =3D dib8000_read32(state, 23) / 1000; + ratio =3D 4; - unit_khz_dds_val =3D (1<<26) / (dib8000_read32(state, 23) / 1000); + + unit_khz_dds_val =3D (1<<26) / (internal ?: 1); if (offset_khz < 0) dds =3D (1 << 26) - (abs_offset_khz * unit_khz_dds_val); else --=20 2.48.1