From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 07B494EA366; Thu, 27 Aug 2026 19:41:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787859681; cv=none; b=bjMd9UJK13w/6wmCHHdZhnPgxVFU5uTmSPN+DH9ODLgrlfgldaGHI0yyORlRTYWr5hcSLTjiO1cIYvx7TN8AHtjpwNdSXC/IkjA0FkVBP+l40EisWqB3FQVmoETHJUqHNJ+VltLT4L+ApH+CWGyPHHZFnb6IUDtjLTO9y4/7bE8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787859681; c=relaxed/simple; bh=0P6eMkkRG2b1z1PqpBTFusEK4LUyKsguFzEEnn00V84=; h=Content-Type:MIME-Version:Subject:From:Message-Id:Date:References: In-Reply-To:To:Cc; b=HTbzsVP2yPk7PNbSzkFRDPHcFCeSaS8JbRUfblkb8XtwmJF/WEXphzc9Rpfl043SBshTCi1s/ChoeJXR32cjKWwyy8TRD19SspSz0V5A1MevtHbPlTZHMzfQIBboVKIIjHMwlFpNm2T5OcVwo/kFGjsqxI9MfLAIyXOPjIQISMk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=K4rQVz93; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="K4rQVz93" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A512C1F000E9; Thu, 27 Aug 2026 19:41:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1787859679; bh=hKmzTWG2QTTLM4z7Fbpyu8BdhihGCi8BMyjswsDYkag=; h=Subject:From:Date:References:In-Reply-To:To:Cc; b=K4rQVz93JFbiwx9l0iuxF9e6oP5YBuDC5Y3UpUSiA/fQxW9Hc2gtqlGGsfIt9R57M 1d84bW9RnKd57kaQSN0rCfFMoeyEc6zvZvu9NmbeFDnEYZZV1BVEfpnYMQ0+KW7cae BG2WauRV+wQOTk9y+VoXnYyxeWfFQIUViUherUQXJTQR9El/0qBvwEI3Q4Ew5H9VfL 4i62rTt/3qkbMDUrFwMgfdGaj9hC5TM2IE8gq4Y9hkrEXEf2Wg1sdLzl0zDl5HNvlM 3iOSA6V0drrvNxXaXvdPAxQxF2hrZBjPlLidT12gMjWaPm6pUYBHmHtupevYc6mD2C FZqN9qLgYo83g== Received: from [10.30.226.235] (localhost [IPv6:::1]) by aws-us-west-2-korg-oddjob-rhel9-1.codeaurora.org (Postfix) with ESMTP id 568AB3809A8D; Thu, 27 Aug 2026 19:40:26 +0000 (UTC) Content-Type: text/plain; charset="utf-8" Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: Re: [PATCH net v2] net/sched: bound qdisc_pkt_len to prevent qdisc soft lockup From: patchwork-bot+netdevbpf@kernel.org Message-Id: <178785962489.1816627.15370775137740207387.git-patchwork-notify@kernel.org> Date: Thu, 27 Aug 2026 19:40:24 +0000 References: <20260825081403.133992-1-jhs@mojatatu.com> In-Reply-To: <20260825081403.133992-1-jhs@mojatatu.com> To: Jamal Hadi Salim Cc: netdev@vger.kernel.org, jiri@resnulli.us, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, horms@kernel.org, stable@vger.kernel.org, vega@nebusec.ai, victor@mojatatu.com Hello: This patch was applied to netdev/net.git (main) by Jakub Kicinski : On Tue, 25 Aug 2026 04:14:03 -0400 you wrote: > qdisc_get_stab() accepts a user-supplied size table, and > __qdisc_calculate_pkt_len() amplifies qdisc_pkt_len() through the > overhead, the size-table data (u16), and size_log (up to > STAB_SIZE_LOG_MAX). A crafted stab can therefore set qdisc_pkt_len() > to ~1 GiB for an ordinary skb. Per-flow deficit schedulers such as > DRR and ETS replenish one quantum per loop iteration; with a tiny > quantum (1) they spin billions of times under the qdisc lock, > producing a soft lockup / RCU stall as illustrated by vega@nebusec.ai. > > [...] Here is the summary with links: - [net,v2] net/sched: bound qdisc_pkt_len to prevent qdisc soft lockup https://git.kernel.org/netdev/net/c/8f735d64382d You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html