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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 A60ADC2BB85 for ; Thu, 16 Apr 2020 13:59:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7C0462078B for ; Thu, 16 Apr 2020 13:59:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587045576; bh=P/0lskj5n+fVsZdBwi59YdaK/6ajOC5ljhBBmqt4dHw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=rI6zZtIPwmRWlKYJUtvueDa6mcQg4Y4Dv3R+qy3VsNq2dkGXzbOqHc/tEXbKE/E0D SoqYTVYpDx2W8EdJ/vQ96qJ98XKb56e6YimnVVk6t7lfLAZTU597yIbSRjQHTQXADX D8sY1DCH9mjqoMgkF1c146LcZbrJnGe4Cd5WKsqc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729162AbgDPN7e (ORCPT ); Thu, 16 Apr 2020 09:59:34 -0400 Received: from mail.kernel.org ([198.145.29.99]:52568 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2898049AbgDPNkD (ORCPT ); Thu, 16 Apr 2020 09:40:03 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 CF23520732; Thu, 16 Apr 2020 13:40:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587044402; bh=P/0lskj5n+fVsZdBwi59YdaK/6ajOC5ljhBBmqt4dHw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bQja+geixbrFiiX3egihn9sTb0/tcWbEK6YJGTfPupIyvHU5cl2lBVmEFM5Je9InM MtqTsfQkoQBKZOV31cYbEvNgHfZ8GMDoOnSy5zuQR++cHJ2Z1c13OOhygqZbhMWsxn H3RloXmC98iNMw75YeXGfW6Dw0k/2RCxy3hnRPm4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Suzuki K Poulose , Fredrik Strupe , Catalin Marinas Subject: [PATCH 5.5 201/257] arm64: armv8_deprecated: Fix undef_hook mask for thumb setend Date: Thu, 16 Apr 2020 15:24:12 +0200 Message-Id: <20200416131351.219534451@linuxfoundation.org> X-Mailer: git-send-email 2.26.1 In-Reply-To: <20200416131325.891903893@linuxfoundation.org> References: <20200416131325.891903893@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: Fredrik Strupe commit fc2266011accd5aeb8ebc335c381991f20e26e33 upstream. For thumb instructions, call_undef_hook() in traps.c first reads a u16, and if the u16 indicates a T32 instruction (u16 >= 0xe800), a second u16 is read, which then makes up the the lower half-word of a T32 instruction. For T16 instructions, the second u16 is not read, which makes the resulting u32 opcode always have the upper half set to 0. However, having the upper half of instr_mask in the undef_hook set to 0 masks out the upper half of all thumb instructions - both T16 and T32. This results in trapped T32 instructions with the lower half-word equal to the T16 encoding of setend (b650) being matched, even though the upper half-word is not 0000 and thus indicates a T32 opcode. An example of such a T32 instruction is eaa0b650, which should raise a SIGILL since T32 instructions with an eaa prefix are unallocated as per Arm ARM, but instead works as a SETEND because the second half-word is set to b650. This patch fixes the issue by extending instr_mask to include the upper u32 half, which will still match T16 instructions where the upper half is 0, but not T32 instructions. Fixes: 2d888f48e056 ("arm64: Emulate SETEND for AArch32 tasks") Cc: # 4.0.x- Reviewed-by: Suzuki K Poulose Signed-off-by: Fredrik Strupe Signed-off-by: Catalin Marinas Signed-off-by: Greg Kroah-Hartman --- arch/arm64/kernel/armv8_deprecated.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/arm64/kernel/armv8_deprecated.c +++ b/arch/arm64/kernel/armv8_deprecated.c @@ -601,7 +601,7 @@ static struct undef_hook setend_hooks[] }, { /* Thumb mode */ - .instr_mask = 0x0000fff7, + .instr_mask = 0xfffffff7, .instr_val = 0x0000b650, .pstate_mask = (PSR_AA32_T_BIT | PSR_AA32_MODE_MASK), .pstate_val = (PSR_AA32_T_BIT | PSR_AA32_MODE_USR),