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 19FA1C433EF for ; Tue, 12 Jul 2022 18:55:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234134AbiGLSzJ (ORCPT ); Tue, 12 Jul 2022 14:55:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33460 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234189AbiGLSy2 (ORCPT ); Tue, 12 Jul 2022 14:54:28 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 18FACE95E6; Tue, 12 Jul 2022 11:45:57 -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 ams.source.kernel.org (Postfix) with ESMTPS id 52EDBB81BB9; Tue, 12 Jul 2022 18:45:54 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B269AC3411E; Tue, 12 Jul 2022 18:45:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1657651553; bh=U/+eLCYI4YDKjT6BcIXjKCgdRxC0oXdMaxjk/f6TANk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=j7s7M7OABmPu4uzyUCB29OjRS8xmZHvzmtFhm4XDD9dxWnJAnq9a389dLall06rGX uG4uuX5sm6hcy/9yD8KjnDLlKhiwWP/bpu/eqlS8yodpbayS/vdmfl0hwFhuOoPN0S cAF0FjckdesNEXvOxRyPL1upAiGdkDyg8aFeywig= 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 , Ben Hutchings Subject: [PATCH 5.10 081/130] x86/retpoline: Swizzle retpoline thunk Date: Tue, 12 Jul 2022 20:38:47 +0200 Message-Id: <20220712183250.196932918@linuxfoundation.org> X-Mailer: git-send-email 2.37.0 In-Reply-To: <20220712183246.394947160@linuxfoundation.org> References: <20220712183246.394947160@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: linux-kernel@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: Ben Hutchings 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 @@ -32,9 +32,9 @@ SYM_INNER_LABEL(__x86_indirect_thunk_\reg, SYM_L_GLOBAL) UNWIND_HINT_EMPTY - 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