From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9D903C5CFC1 for ; Mon, 17 Aug 2026 08:26:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To: Content-Transfer-Encoding:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=EH4tDs/d5HwbhZaxavUhyBAHCbild7wYmuQeNMNmXvE=; b=ttfCVGVM2Zl6oj/I37T6JjozFT +hGTyt+nweIajg+c8qoCTW68R0IDWXqoKoh3hwIscqXC19ZKMWbRqOPFUrlES+tfd7/Bj8NONzmOJ dPon91aiHV4jhdnbCeOSJ+zlLMBBat6CaNCrRzWpODEMLJaB8QfCim4wDFpmf286YmtlJ1c+tpX0X E3g6pRvtN/krXnKMITA1dy1VWVmAxDJFYvInRRyx8eP1AjrnEBXV7EtocrLUUGx+QSZFph+B509nW 36IyJAaaoKClaNCEaPOqoD+f3MNYQB48kSTr63/Kss5R+jnJsjtaxclp2rCfZcEzHosEBfY+m9n9z hxSj8bxQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wvsfU-00000005gLm-3apS; Mon, 17 Aug 2026 08:26:04 +0000 Received: from out-118.mta0.migadu.com ([2001:41d0:1004:224b::76] helo=mta0.migadu.com) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wvrvy-00000005ZlA-1bod for linux-nvme@lists.infradead.org; Mon, 17 Aug 2026 07:39:04 +0000 X-Envelope-To: linux-nvme@lists.infradead.org DKIM-Signature: a=rsa-sha256; bh=4YGgPm1wRAd8vr5pINF7lmz4ylld4f9QdvgoaXgstqU=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1786952338; v=1; x=1787557138; b=drKkCzKSsin9zuHKenvfN9Z2FT92faus9G8LzAbDREnbR3c36ZnwAZwQ92sXsS+0GRnErubh jak7uy/R270dwWU2uNt0CkImdFXguvI2TIumQCaIJyEBLAIyuyEDzuo49xBXaGmyuG+Zalx6zp6 sUzdcJHuBYYvj+Fdx2BMVJ9g= X-Envelope-To: linux-nvme@lists.infradead.org Received: from localhost (3.112.29.171) by mta12.migadu.com with ESMTPS id 17e9312474d067d5; Mon, 17 Aug 2026 07:38:57 +0000 X-Migadu-Flow: FLOW_OUT Date: Mon, 17 Aug 2026 15:38:53 +0800 From: Baoquan He To: Lukas Wunner , Jan Sebastian =?iso-8859-1?Q?G=F6tte?= Cc: Jan Sebastian =?iso-8859-1?Q?G=F6tte?= , Andrew Morton , Mike Rapoport , Pasha Tatashin , Pratyush Yadav , Dave Young , Catalin Marinas , Will Deacon , David Howells , Jarkko Sakkinen , Jonathan Corbet , Shuah Khan , Paul Moore , James Morris , "Serge E. Hallyn" , Ignat Korchagin , Herbert Xu , "David S. Miller" , Keith Busch , Jens Axboe , Christoph Hellwig , Sagi Grimberg , Trond Myklebust , Anna Schumaker , Mimi Zohar , James Bottomley , Marc Dionne , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Eric Biggers , "Theodore Y. Ts'o" , Jaegeuk Kim , Alexander Viro , Christian Brauner , Jan Kara , Alasdair Kergon , Mike Snitzer , Mikulas Patocka , Benjamin Marzinski , kexec@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, keyrings@vger.kernel.org, linux-doc@vger.kernel.org, linux-security-module@vger.kernel.org, linux-crypto@vger.kernel.org, linux-nvme@lists.infradead.org, linux-nfs@vger.kernel.org, linux-integrity@vger.kernel.org, linux-afs@lists.infradead.org, netdev@vger.kernel.org, linux-fscrypt@vger.kernel.org, linux-fsdevel@vger.kernel.org, dm-devel@lists.linux.dev Subject: Re: [PATCH v2 01/13] kexec: add CRASH_WIPE_SECRETS to wipe secrets before kdump Message-ID: References: <20260811-crash-zeroize-rework-v2-0-9561d13c2340@jaseg.de> <20260811-crash-zeroize-rework-v2-1-9561d13c2340@jaseg.de> <9765f7ea-36bb-4c7b-a19b-7facec97b762@jaseg.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260817_003902_554361_DF16E54D X-CRM114-Status: GOOD ( 17.89 ) X-Mailman-Approved-At: Mon, 17 Aug 2026 01:26:02 -0700 X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On 08/16/26 at 02:13pm, Lukas Wunner wrote: > On Wed, Aug 12, 2026 at 12:08:39PM +0200, Jan Sebastian Götte wrote: > > I can imagine one alternative way to approach this, tell me what you think: > > Instead of registering wipe handlers that memzero places on panic, I could > > put an optional registry of (addr, len) descriptors into crashkernel memory > > that the original kernel populates with the PAs of buffers to clear ahead of > > time. Then the kdump kernel could do the actual memzero. This would remove > > all code from the actual kdump path here. The registry could be made > > per-core to avoid locks. Since there are a lot of security expert in CC, I am wondering what's the risk if we wipe secrets during dumping. System is located in user's place, and vmcore is dumped and collected in user's place. If we filter out secrets memory when we dumping, what could be leaked out? > > Or create a dedicated mempool from which all sensitive data is allocated, > then call mempool_free_bulk() on kexec to poison everything in that pool? > > Thanks, > > Lukas