From patchwork Wed Apr 10 07:21:49 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Tokarev X-Patchwork-Id: 1921751 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=patchwork.ozlabs.org) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4VDvW62qdCz1yYB for ; Wed, 10 Apr 2024 17:25:38 +1000 (AEST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ruSJq-0002N4-LB; Wed, 10 Apr 2024 03:24:32 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ruSJh-0001ZO-E2; Wed, 10 Apr 2024 03:24:21 -0400 Received: from isrv.corpit.ru ([86.62.121.231]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ruSJf-0003y3-Ir; Wed, 10 Apr 2024 03:24:21 -0400 Received: from tsrv.corpit.ru (tsrv.tls.msk.ru [192.168.177.2]) by isrv.corpit.ru (Postfix) with ESMTP id 907585D67F; Wed, 10 Apr 2024 10:25:03 +0300 (MSK) Received: from tls.msk.ru (mjt.wg.tls.msk.ru [192.168.177.130]) by tsrv.corpit.ru (Postfix) with SMTP id 34AA9B02C0; Wed, 10 Apr 2024 10:23:05 +0300 (MSK) Received: (nullmailer pid 4191693 invoked by uid 1000); Wed, 10 Apr 2024 07:23:04 -0000 From: Michael Tokarev To: qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org, Nick Briggs , Peter Maydell , Jason Wang , Michael Tokarev Subject: [Stable-8.2.3 16/87] Avoid unaligned fetch in ladr_match() Date: Wed, 10 Apr 2024 10:21:49 +0300 Message-Id: <20240410072303.4191455-16-mjt@tls.msk.ru> X-Mailer: git-send-email 2.39.2 In-Reply-To: References: MIME-Version: 1.0 Received-SPF: pass client-ip=86.62.121.231; envelope-from=mjt@tls.msk.ru; helo=isrv.corpit.ru X-Spam_score_int: -68 X-Spam_score: -6.9 X-Spam_bar: ------ X-Spam_report: (-6.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_HI=-5, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org From: Nick Briggs There is no guarantee that the PCNetState is allocated such that csr[8] is allocated on an 8-byte boundary. Since not all hosts are capable of unaligned fetches the 16-bit elements need to be fetched individually to avoid a potential fault. Closes issue #2143 Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2143 Signed-off-by: Nick Briggs Reviewed-by: Peter Maydell Signed-off-by: Jason Wang (cherry picked from commit 6a5287ce80470bb8df95901d73ee779a64e70c3a) Signed-off-by: Michael Tokarev diff --git a/hw/net/pcnet.c b/hw/net/pcnet.c index a7e123e60d..7d574f487b 100644 --- a/hw/net/pcnet.c +++ b/hw/net/pcnet.c @@ -632,7 +632,7 @@ static inline int ladr_match(PCNetState *s, const uint8_t *buf, int size) { struct qemu_ether_header *hdr = (void *)buf; if ((*(hdr->ether_dhost)&0x01) && - ((uint64_t *)&s->csr[8])[0] != 0LL) { + (s->csr[8] | s->csr[9] | s->csr[10] | s->csr[11]) != 0) { uint8_t ladr[8] = { s->csr[8] & 0xff, s->csr[8] >> 8, s->csr[9] & 0xff, s->csr[9] >> 8,