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 X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8F9C0CA9EC9 for ; Mon, 4 Nov 2019 22:15:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 640E7214D8 for ; Mon, 4 Nov 2019 22:15:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572905715; bh=rRwePNsI59KK4BLYIYjRoGLaieBH2kehmZF/8DC2UNM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=0MvDnSXAyuPZgqx80yD/SszvCgWo7cL9C6Zt5LiS2Q5mSBvwUr+qKWKwpiIlZ39sp kHQzSl8BHgpoccdSNlY90qb3NiUdiDOn5r7h5h44GGHQh1Ks8iFj4QPsNVH1Wm7DwG IbPJEYQcXHsdljsd1lhNzL86V/4BOzB+FHOJfH10= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389953AbfKDWGX (ORCPT ); Mon, 4 Nov 2019 17:06:23 -0500 Received: from mail.kernel.org ([198.145.29.99]:38088 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389924AbfKDWGS (ORCPT ); Mon, 4 Nov 2019 17:06:18 -0500 Received: from localhost (6.204-14-84.ripe.coltfrance.com [84.14.204.6]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id BC23620650; Mon, 4 Nov 2019 22:06:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572905178; bh=rRwePNsI59KK4BLYIYjRoGLaieBH2kehmZF/8DC2UNM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RwxgJ9TYiEUwjCkkmNMcCSnUkGX9BMs0WZbsvkD23qvkZAzaos4PNd+t/KsGG2BIV NsgJLboC0G5AdxufLBzXXH4XpBvUm2cWXNs3/2RRhOZ7+9MF1QjzvDI87ncwQRMMPL mLmsAVGZU45vLgXONiT/DsaIvRgbtFYGgQ2BxSUQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vincent Chen , Christoph Hellwig , Paul Walmsley , Sasha Levin Subject: [PATCH 5.3 056/163] riscv: Correct the handling of unexpected ebreak in do_trap_break() Date: Mon, 4 Nov 2019 22:44:06 +0100 Message-Id: <20191104212144.176069663@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191104212140.046021995@linuxfoundation.org> References: <20191104212140.046021995@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Vincent Chen [ Upstream commit 8bb0daef64e5a92db63ad1d3bbf9e280a7b3612a ] For the kernel space, all ebreak instructions are determined at compile time because the kernel space debugging module is currently unsupported. Hence, it should be treated as a bug if an ebreak instruction which does not belong to BUG_TRAP_TYPE_WARN or BUG_TRAP_TYPE_BUG is executed in kernel space. For the userspace, debugging module or user problem may intentionally insert an ebreak instruction to trigger a SIGTRAP signal. To approach the above two situations, the do_trap_break() will direct the BUG_TRAP_TYPE_NONE ebreak exception issued in kernel space to die() and will send a SIGTRAP to the trapped process only when the ebreak is in userspace. Signed-off-by: Vincent Chen Reviewed-by: Christoph Hellwig [paul.walmsley@sifive.com: fixed checkpatch issue] Signed-off-by: Paul Walmsley Signed-off-by: Sasha Levin --- arch/riscv/kernel/traps.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c index 82f42a55451eb..93742df9067fb 100644 --- a/arch/riscv/kernel/traps.c +++ b/arch/riscv/kernel/traps.c @@ -130,8 +130,6 @@ asmlinkage void do_trap_break(struct pt_regs *regs) type = report_bug(regs->sepc, regs); switch (type) { #ifdef CONFIG_GENERIC_BUG - case BUG_TRAP_TYPE_NONE: - break; case BUG_TRAP_TYPE_WARN: regs->sepc += get_break_insn_length(regs->sepc); return; @@ -140,8 +138,10 @@ asmlinkage void do_trap_break(struct pt_regs *regs) default: die(regs, "Kernel BUG"); } + } else { + force_sig_fault(SIGTRAP, TRAP_BRKPT, + (void __user *)(regs->sepc)); } - force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)(regs->sepc)); } #ifdef CONFIG_GENERIC_BUG -- 2.20.1