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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0DA91C43334 for ; Fri, 22 Jul 2022 09:08:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234392AbiGVJIv (ORCPT ); Fri, 22 Jul 2022 05:08:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38860 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234616AbiGVJIm (ORCPT ); Fri, 22 Jul 2022 05:08:42 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8B053868AE; Fri, 22 Jul 2022 02:08:41 -0700 (PDT) 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 dfw.source.kernel.org (Postfix) with ESMTPS id 1D67761E95; Fri, 22 Jul 2022 09:08:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 27383C341C6; Fri, 22 Jul 2022 09:08:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1658480920; bh=H1oq4uVfA8R9mjZ/zPPVepCseKRffdac0+kAYkJLC2o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MYcVagKrgvlWzWuU+AQe32SVhy57U1J7G0kzRaxyiiZHxPVKk2iPUoy80xJZcsy+a 9gIg+A6fyuVk4mns9IK86bYCvlNBun0Chf+iV1ALje03h/44RoL/TFGcMNF/LDggwj Vd4UbhIqng3OeyMsIuPc8ZGCGpQNOK8qI1G0Yk04= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Peter Zijlstra (Intel)" , Borislav Petkov , Josh Poimboeuf , Thadeu Lima de Souza Cascardo Subject: [PATCH 5.18 09/70] x86/retpoline: Swizzle retpoline thunk Date: Fri, 22 Jul 2022 11:07:04 +0200 Message-Id: <20220722090651.243991905@linuxfoundation.org> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20220722090650.665513668@linuxfoundation.org> References: <20220722090650.665513668@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Peter Zijlstra commit 00e1533325fd1fb5459229fe37f235462649f668 upstream. Put the actual retpoline thunk as the original code so that it can become more complicated. Specifically, it allows RET to be a JMP, which can't be .altinstr_replacement since that doesn't do relocations (except for the very first instruction). Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Borislav Petkov Reviewed-by: Borislav Petkov Reviewed-by: Josh Poimboeuf Signed-off-by: Borislav Petkov Signed-off-by: Thadeu Lima de Souza Cascardo Signed-off-by: Greg Kroah-Hartman --- arch/x86/lib/retpoline.S | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/arch/x86/lib/retpoline.S +++ b/arch/x86/lib/retpoline.S @@ -33,9 +33,9 @@ SYM_INNER_LABEL(__x86_indirect_thunk_\re UNWIND_HINT_EMPTY ANNOTATE_NOENDBR - ALTERNATIVE_2 __stringify(ANNOTATE_RETPOLINE_SAFE; jmp *%\reg), \ - __stringify(RETPOLINE \reg), X86_FEATURE_RETPOLINE, \ - __stringify(lfence; ANNOTATE_RETPOLINE_SAFE; jmp *%\reg; int3), X86_FEATURE_RETPOLINE_LFENCE + ALTERNATIVE_2 __stringify(RETPOLINE \reg), \ + __stringify(lfence; ANNOTATE_RETPOLINE_SAFE; jmp *%\reg; int3), X86_FEATURE_RETPOLINE_LFENCE, \ + __stringify(ANNOTATE_RETPOLINE_SAFE; jmp *%\reg), ALT_NOT(X86_FEATURE_RETPOLINE) .endm