From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792531463; b=YgmMD5018y5GeYCvocN2/RyMzp9fHLn6Tlv1Sq0Fw+dFtyGOCnC6Ex+mXjitBEMNzTSY PBu8EZwASoTpMAZ5jixO2KyDIdG++/MRhtjjLUv0SqqsJ+2gdXIpr0ycvkeaSR07kv7Pi DMFKIYvpBj/al4Xmeugv72msbz3WVZO410gczniDOpsdlq0J6KIm/VfIQW1Kt4oWcgbvx SowcwatCF/C+WuqjN8h3R2yKN91goZc2lDnY9wXajKg5Si0zgSCxWL3y1+dCXHcVG3ZC3 h4DJa0g/WuIwuoP1iWQYv4ht9osmPfN21kxwIJ99sRqft+ef7unzQlzfUZyqTDIIuKg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792531463; h=Received:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: In-Reply-To:References:MIME-Version:Content-Type: Content-Transfer-Encoding; bh=STrst9SrpXoSVAK4PC7vTr3xKXi6S1Q42DDDXCj6kpQ=; b=WWu2lh2qwSMCsB28EXTHel0asucy9ol00paZXY2imHqryN+znSC5x8UwnFswis7r3Kgs VHjyoiLIte5D8LVEEnqKTJnYJUSWdHNzCm03/uZGQJtVID6lK6TF4TpNyWWXZPS6gVPCM +A/e5AQiFUaO+E15skEOhaH4Psta5pwjq2Sbwak7Dc4OIDzVqy78siunk+yi4ACuTQctV OrQrqAiUFFMMwlbnuR/XP/FgiPm8i3xOFqDAcxsFvtKqzahyKqJQhIt7XZuszxhi1vuDw IcKollyy03Zx34sVmJQLUJSNeG9iSYYcfadaAaKvC6IjAsAzeO+cjYsmLLmcYLtwyTw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=BW0f4rtW; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9468A606A319; Tue, 20 Oct 2026 21:24:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=BW0f4rtW Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1E2301F000C9; Tue, 20 Oct 2026 21:24:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792531463; bh=STrst9SrpXoSVAK4PC7vTr3xKXi6S1Q42DDDXCj6kpQ=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=BW0f4rtW14mj7iJ5vAhav2X7ObRlhRt3sWJMfwSNGuRQr9F8etr6VD3Ipkqy6AZ1u u0cTS/0Ul6YcKeAZ1MnASv+HmBySHksVrRkypmINxZxxUXFsNWodfZWSBtTZfTfsfU xxu6RjTSNNQ9bY3kJxlxv3ELjqup41YfwURnTXBWXjM6FuuXiIZH8wrscaz/uU7+QQ vQ6MFLi8idjaBa5JrpbbOTC6bbfIB7bZIpTLMgVI2oOHqwrua6VOfLv6cYqCHN8LQM kjLtHSCctOJ/9oahQ3kFiTqDhHIGqov7/pLeEu2H+eSb64Bt2Nk2VfEVHaqvI0WK6V 51F4fSBr9wAFA== Date: Tue, 20 Oct 2026 14:24:22 -0700 From: Jakub Kicinski To: Wei Tao Cc: jhs@mojatatu.com, jiri@resnulli.us, davem@davemloft.net, edumazet@kernel.org, pabeni@redhat.com, horms@kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH net] net/sched: cls_flow: avoid integer overflow in perturb_period Message-ID: <20261020142422.7ae3e051@kernel.org> In-Reply-To: <20261016040330.59041-1-taowei@kylinos.cn> References: <20261016040330.59041-1-taowei@kylinos.cn> X-Mailing-List: netdev@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Fri, 16 Oct 2026 12:03:30 +0800 Wei Tao wrote: > flow_change() calculates perturb_period by directly multiplying > nla_get_u32(tb[TCA_FLOW_PERTURB]) by HZ, without any overflow > protection. Since perturb_period is a u32, the multiplication > overflows when the value from netlink exceeds UINT_MAX / HZ. > The result can be an unexpectedly short period or even zero. Same questions / treatment as your cls_fw patch. -- pw-bot: cr