From nobody Mon Nov 25 14:52:18 2024 Received: from szxga05-in.huawei.com (szxga05-in.huawei.com [45.249.212.191]) (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 E982A4436A; Sat, 26 Oct 2024 07:34:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.191 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729928077; cv=none; b=DG0FrVPyNdE06W0r4hQ1ARwvMYT5Z/tJSbABa0/4zqsa215vvWiYpFgPFdDIGjXoWTULLGGVf04Ji014YdOpUyywdrMk69PQqk2yJf1GGVCq/D4dGwzoMf4Q7xPvNcivfyot27RL1iJnjAvxB4WgvQxBXaPu/ZjsSiu5FgixLPg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729928077; c=relaxed/simple; bh=gK6X9hMg+YlJBU0ffnq9HX2/9dW8lyP0eQfyfJiUkwo=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=ezG1ROG7Zs4R7yK2BhmUbwDDbJuqGPUCVVCv/jrkvianaQ1uZXo9fWD+rmg5lpdRtbDWeGjOtIebizarEOl+XRFrGd3RzeUDHYSySC/jWeRpvfERhcHEMjQZKy8ctVg9j4pVcU+H7lfY/xUd2iW22p8OupNEMSrM6vv+UDLDh4Q= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.191 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.88.163]) by szxga05-in.huawei.com (SkyGuard) with ESMTP id 4XbBFr3W0qz1jvrm; Sat, 26 Oct 2024 15:33:04 +0800 (CST) Received: from kwepemd200012.china.huawei.com (unknown [7.221.188.145]) by mail.maildlp.com (Postfix) with ESMTPS id 25CB818001B; Sat, 26 Oct 2024 15:34:31 +0800 (CST) Received: from huawei.com (10.67.175.84) by kwepemd200012.china.huawei.com (7.221.188.145) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1258.34; Sat, 26 Oct 2024 15:34:30 +0800 From: Zicheng Qu To: , , , , , CC: , , , Subject: [PATCH] clk: clk-axi-clkgen: fix division by zero in axi_clkgen_calc_params() Date: Sat, 26 Oct 2024 07:23:44 +0000 Message-ID: <20241026072344.976154-1-quzicheng@huawei.com> X-Mailer: git-send-email 2.34.1 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 X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To kwepemd200012.china.huawei.com (7.221.188.145) Content-Type: text/plain; charset="utf-8" In the axi_clkgen_set_rate() function, parameters fin and fout are checked in advance to ensure they are not equal to zero. However, in the axi_clkgen_calc_params() function, they might become zero after /=3D 1000. This could lead to a division by zero error when calculating fvco_max_fract * d_max / fin or DIV_ROUND_CLOSEST(fvco, fout). The same issue occurs in the axi_clkgen_determine_rate() function, where there is no check to ensure they are non-zero. Fixes: 0e646c52cf0e ("clk: Add axi-clkgen driver") Cc: Signed-off-by: Zicheng Qu --- drivers/clk/clk-axi-clkgen.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/clk/clk-axi-clkgen.c b/drivers/clk/clk-axi-clkgen.c index bf4d8ddc93ae..369b15a2660e 100644 --- a/drivers/clk/clk-axi-clkgen.c +++ b/drivers/clk/clk-axi-clkgen.c @@ -344,7 +344,7 @@ static int axi_clkgen_set_rate(struct clk_hw *clk_hw, uint32_t filter; uint32_t lock; =20 - if (parent_rate =3D=3D 0 || rate =3D=3D 0) + if (parent_rate < 1000 || rate < 1000) return -EINVAL; =20 axi_clkgen_calc_params(limits, parent_rate, rate, &d, &m, &dout); @@ -392,6 +392,9 @@ static int axi_clkgen_determine_rate(struct clk_hw *hw, unsigned int d, m, dout; unsigned long long tmp; =20 + if (req->best_parent_rate < 1000 || req->rate < 1000) + return -EINVAL; + axi_clkgen_calc_params(limits, req->best_parent_rate, req->rate, &d, &m, &dout); =20 --=20 2.34.1