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=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 6D463C432C3 for ; Fri, 22 Nov 2019 10:55:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 40D8920706 for ; Fri, 22 Nov 2019 10:55:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574420155; bh=+MDVunTPEMMpFv/BUNtzZS6Dddws/K6pUWQKAluF6Go=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=QxOt/vq8t9TMjjn3BV1tdcm97PSOIA0JQDkEbE4XZhy9DYsAN+i11wdx3O91Aliba LGi+orLwioWF5le/n8Xw+AllU9k7GAQRVKlj04FNLSvl6S00Zgpnm6x9KELZ0Yvr3M s5iBCvblpYQSoOf9GmHAgAPy7KfWkVnc/ZNG53MA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728885AbfKVKzx (ORCPT ); Fri, 22 Nov 2019 05:55:53 -0500 Received: from mail.kernel.org ([198.145.29.99]:43108 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730008AbfKVKzv (ORCPT ); Fri, 22 Nov 2019 05:55:51 -0500 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 478AF20718; Fri, 22 Nov 2019 10:55:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574420150; bh=+MDVunTPEMMpFv/BUNtzZS6Dddws/K6pUWQKAluF6Go=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OdhyE+vkLyEvTJ+f2KVMIiTpstK3De+PavoLNpuTZvGza05VnIQx0O4GHLG0yc+dI 1OO5kaLOHT621CGLPtTBVIZNaDMtJRyfMsGZrWzjT8BF2oQNqeloMCyX3hP0qiRzQ7 Ev3BaVMuoalJSvNPY3yJnQHS4qzJWAAl2vCmb3Lw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Wang YanQing , Daniel Borkmann Subject: [PATCH 4.19 011/220] bpf, x32: Fix bug for BPF_ALU64 | BPF_NEG Date: Fri, 22 Nov 2019 11:26:16 +0100 Message-Id: <20191122100913.448861318@linuxfoundation.org> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191122100912.732983531@linuxfoundation.org> References: <20191122100912.732983531@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Wang YanQing commit b9aa0b35d878dff9ed19f94101fe353a4de00cc4 upstream. The current implementation has two errors: 1: The second xor instruction will clear carry flag which is necessary for following sbb instruction. 2: The select coding for sbb instruction is wrong, the coding is "sbb dreg_hi,ecx", but what we need is "sbb ecx,dreg_hi". This patch rewrites the implementation and fixes the errors. This patch fixes below errors reported by bpf/test_verifier in x32 platform when the jit is enabled: " 0: (b4) w1 = 4 1: (b4) w2 = 4 2: (1f) r2 -= r1 3: (4f) r2 |= r1 4: (87) r2 = -r2 5: (c7) r2 s>>= 63 6: (5f) r1 &= r2 7: (bf) r0 = r1 8: (95) exit processed 9 insns (limit 131072), stack depth 0 0: (b4) w1 = 4 1: (b4) w2 = 4 2: (1f) r2 -= r1 3: (4f) r2 |= r1 4: (87) r2 = -r2 5: (c7) r2 s>>= 63 6: (5f) r1 &= r2 7: (bf) r0 = r1 8: (95) exit processed 9 insns (limit 131072), stack depth 0 ...... Summary: 1189 PASSED, 125 SKIPPED, 15 FAILED " Signed-off-by: Wang YanQing Signed-off-by: Daniel Borkmann Signed-off-by: Greg Kroah-Hartman --- arch/x86/net/bpf_jit_comp32.c | 19 ++++++------------- 1 file changed, 6 insertions(+), 13 deletions(-) --- a/arch/x86/net/bpf_jit_comp32.c +++ b/arch/x86/net/bpf_jit_comp32.c @@ -698,19 +698,12 @@ static inline void emit_ia32_neg64(const STACK_VAR(dst_hi)); } - /* xor ecx,ecx */ - EMIT2(0x31, add_2reg(0xC0, IA32_ECX, IA32_ECX)); - /* sub dreg_lo,ecx */ - EMIT2(0x2B, add_2reg(0xC0, dreg_lo, IA32_ECX)); - /* mov dreg_lo,ecx */ - EMIT2(0x89, add_2reg(0xC0, dreg_lo, IA32_ECX)); - - /* xor ecx,ecx */ - EMIT2(0x31, add_2reg(0xC0, IA32_ECX, IA32_ECX)); - /* sbb dreg_hi,ecx */ - EMIT2(0x19, add_2reg(0xC0, dreg_hi, IA32_ECX)); - /* mov dreg_hi,ecx */ - EMIT2(0x89, add_2reg(0xC0, dreg_hi, IA32_ECX)); + /* neg dreg_lo */ + EMIT2(0xF7, add_1reg(0xD8, dreg_lo)); + /* adc dreg_hi,0x0 */ + EMIT3(0x83, add_1reg(0xD0, dreg_hi), 0x00); + /* neg dreg_hi */ + EMIT2(0xF7, add_1reg(0xD8, dreg_hi)); if (dstk) { /* mov dword ptr [ebp+off],dreg_lo */