From nobody Wed Sep 3 06:42:31 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) client-ip=192.237.175.120; envelope-from=xen-devel-bounces@lists.xenproject.org; helo=lists.xenproject.org; Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org; dmarc=pass(p=none dis=none) header.from=linuxfoundation.org ARC-Seal: i=1; a=rsa-sha256; t=1666612984; cv=none; d=zohomail.com; s=zohoarc; b=ErHMltC+gDD5z/Phtm8xwYGws1Ryqun+HtnT490dAJBSljaLU82zE1+aDsLWb8MtvuHzfljLvWA0x2lvdPrH4NfNUEdqzsQMqRIZ54N0WwXn7y5a5SxuTyjtukNXY+Uee4k32t8Biq6tkIjMAsPwoaj+c6QMz2l23H2MMF2MylQ= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1666612984; h=Content-Type:Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To; bh=Vu6DnC/P6o7/3l0/q2sbN/O7vaXsYXzI6YUf1WOVMdE=; b=NJ3oPjfzPe/waSh/iIJgIoYVljJ5OwNqAlHmdHskCMdQn8K6+JyBmX9VZCaMMiIt2Hw/WMVuGUtVg7yi98/EsUEkDPL6uAtOxEAWm/HSDc9dsE473+5hpmIBSJWmn//vVr/Q6eS/j58mLRVu45m0gOD+BoQZYkZy5oH3hFk2Pf4= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org; dmarc=pass header.from= (p=none dis=none) Return-Path: Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) by mx.zohomail.com with SMTPS id 1666612984470818.7374299935751; Mon, 24 Oct 2022 05:03:04 -0700 (PDT) Received: from list by lists.xenproject.org with outflank-mailman.429044.679800 (Exim 4.92) (envelope-from ) id 1omw9p-0007WL-KG; Mon, 24 Oct 2022 12:02:17 +0000 Received: by outflank-mailman (output) from mailman id 429044.679800; Mon, 24 Oct 2022 12:02:17 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1omw9p-0007WE-FZ; Mon, 24 Oct 2022 12:02:17 +0000 Received: by outflank-mailman (input) for mailman id 429044; Mon, 24 Oct 2022 12:02:15 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1omw9n-0007W8-Nc for xen-devel@lists.xenproject.org; Mon, 24 Oct 2022 12:02:15 +0000 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id afd4690e-5393-11ed-8fd0-01056ac49cbb; Mon, 24 Oct 2022 14:02:09 +0200 (CEST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 30B16B81250; Mon, 24 Oct 2022 12:02:14 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 64D13C433D6; Mon, 24 Oct 2022 12:02:12 +0000 (UTC) X-Outflank-Mailman: Message body and most headers restored to incoming version X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: afd4690e-5393-11ed-8fd0-01056ac49cbb DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666612932; bh=HDBZX01FN2W9c75Sd8NoXHb1ZhN7yyXXynCHY/64+/k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pND0li9PULhAZ5WGWsVwxg82gs5hly/Vnn/CKFpKa2LRY7bOsjDtEpcmCVbQwj/O2 gn1YSu/K3jWSnXc47NgdgmPwB9t620DY8KGXQCWZFjktH23fUfjmrYlggGyGdSzy1g 5UskNI2UYgsHLyuQGVhQKGGGC6UFXCP8xlpcR/RA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Juergen Gross , Boris Ostrovsky , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , xen-devel@lists.xenproject.org, Kees Cook , Sasha Levin Subject: [PATCH 4.19 174/229] x86/entry: Work around Clang __bdos() bug Date: Mon, 24 Oct 2022 13:31:33 +0200 Message-Id: <20221024113004.718917343@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221024112959.085534368@linuxfoundation.org> References: <20221024112959.085534368@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ZohoMail-DKIM: pass (identity @linuxfoundation.org) X-ZM-MESSAGEID: 1666612985004100001 Content-Type: text/plain; charset="utf-8" From: Kees Cook [ Upstream commit 3e1730842f142add55dc658929221521a9ea62b6 ] Clang produces a false positive when building with CONFIG_FORTIFY_SOURCE=3Dy and CONFIG_UBSAN_BOUNDS=3Dy when operating on an array with a dynamic offset. Work around this by using a direct assignment of an empty instance. Avoids this warning: ../include/linux/fortify-string.h:309:4: warning: call to __write_overflow_= field declared with 'warn ing' attribute: detected write beyond size of field (1st parameter); maybe = use struct_group()? [-Wat tribute-warning] __write_overflow_field(p_size_field, size); ^ which was isolated to the memset() call in xen_load_idt(). Note that this looks very much like another bug that was worked around: https://github.com/ClangBuiltLinux/linux/issues/1592 Cc: Juergen Gross Cc: Boris Ostrovsky Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: Dave Hansen Cc: x86@kernel.org Cc: "H. Peter Anvin" Cc: xen-devel@lists.xenproject.org Reviewed-by: Boris Ostrovsky Link: https://lore.kernel.org/lkml/41527d69-e8ab-3f86-ff37-6b298c01d5bc@ora= cle.com Signed-off-by: Kees Cook Signed-off-by: Sasha Levin --- arch/x86/xen/enlighten_pv.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c index 8f1ff8dad2ce..04bfd9c3987b 100644 --- a/arch/x86/xen/enlighten_pv.c +++ b/arch/x86/xen/enlighten_pv.c @@ -752,6 +752,7 @@ static void xen_load_idt(const struct desc_ptr *desc) { static DEFINE_SPINLOCK(lock); static struct trap_info traps[257]; + static const struct trap_info zero =3D { }; unsigned out; =20 trace_xen_cpu_load_idt(desc); @@ -761,7 +762,7 @@ static void xen_load_idt(const struct desc_ptr *desc) memcpy(this_cpu_ptr(&idt_desc), desc, sizeof(idt_desc)); =20 out =3D xen_convert_trap_info(desc, traps, false); - memset(&traps[out], 0, sizeof(traps[0])); + traps[out] =3D zero; =20 xen_mc_flush(); if (HYPERVISOR_set_trap_table(traps)) --=20 2.35.1