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 50F7CC6FD18 for ; Fri, 31 Mar 2023 13:38:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=N0U9+L2vGhiFlUSMje+zFgCBXEgh74D1IUozqflwnB4=; b=LqUFRYE+82h/6m /tKva7rlIg5W2wI3/Z/crtkaK6zJHN/IEtsHHPDpjorzYr9pnEnrGsOsLJo9fc5xJohlkn5toyy9j LcDB4f9b7GK7rUbB8w2YVPQIhf8RXLSnpO9m+AxPfELM2/UoD6Ewr60v5Hoo0ZSXbNS3ZsFXGaCSg JgnWYLfqQxZD1zLpIy2hikbbtPRrQdxBY33t1JNiUmiqZ2pUgNOzBYXrYjE5+EdYZ5un05PxkGlb2 2r8N9DbVX3NfNNxcfcu+i3EwOzoIZzvFzx4pDMcP9WK78CVJjj8R3SeurTVl+ACFyvC3QqgtYJR9Q 4y7GkYmWZco63UWJkIEg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1piExt-007YMT-2K; Fri, 31 Mar 2023 13:38:49 +0000 Received: from gloria.sntech.de ([185.11.138.130]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1piExp-007YLp-1W; Fri, 31 Mar 2023 13:38:47 +0000 Received: from ip4d1634d3.dynamic.kabel-deutschland.de ([77.22.52.211] helo=diego.localnet) by gloria.sntech.de with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1piExm-0003vk-Sw; Fri, 31 Mar 2023 15:38:42 +0200 From: Heiko =?ISO-8859-1?Q?St=FCbner?= To: linux-riscv@lists.infradead.org, palmer@dabbelt.com, anup@brainfault.org, atishp@atishpatra.org, kvm-riscv@lists.infradead.org, kvm@vger.kernel.org Cc: vineetg@rivosinc.com, greentime.hu@sifive.com, guoren@linux.alibaba.com, ShihPo Hung , Vincent Chen , Andy Chiu , Paul Walmsley , Albert Ou , Conor Dooley , Masahiro Yamada , Alexandre Ghiti , Guo Ren , Andy Chiu Subject: Re: [PATCH -next v17 16/20] riscv: prevent stack corruption by reserving task_pt_regs(p) early Date: Fri, 31 Mar 2023 15:38:41 +0200 Message-ID: <14872268.tv2OnDr8pf@diego> In-Reply-To: <20230327164941.20491-17-andy.chiu@sifive.com> References: <20230327164941.20491-1-andy.chiu@sifive.com> <20230327164941.20491-17-andy.chiu@sifive.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230331_063845_528338_C04EEFB6 X-CRM114-Status: GOOD ( 10.81 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org Am Montag, 27. M=E4rz 2023, 18:49:36 CEST schrieb Andy Chiu: > From: Greentime Hu > = > Early function calls, such as setup_vm(), relocate_enable_mmu(), > soc_early_init() etc, are free to operate on stack. However, > PT_SIZE_ON_STACK bytes at the head of the kernel stack are purposedly > reserved for the placement of per-task register context pointed by > task_pt_regs(p). Those functions may corrupt task_pt_regs if we overlap > the $sp with it. In fact, we had accidentally corrupted sstatus.VS in some > tests, treating the kernel to save V context before V was actually > allocated, resulting in a kernel panic. > = > Thus, we should skip PT_SIZE_ON_STACK for $sp before making C function > calls from the top-level assembly. > = > Co-developed-by: ShihPo Hung > Signed-off-by: ShihPo Hung > Co-developed-by: Vincent Chen > Signed-off-by: Vincent Chen > Signed-off-by: Greentime Hu > Signed-off-by: Andy Chiu > Reviewed-by: Conor Dooley Reviewed-by: Heiko Stuebner Tested-by: Heiko Stuebner _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv