From patchwork Thu Apr 21 15:07:49 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Schoenebeck X-Patchwork-Id: 12821947 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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5A1F7C433F5 for ; Thu, 21 Apr 2022 16:27:15 +0000 (UTC) Received: from localhost ([::1]:50584 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nhZeC-0003vK-7M for qemu-devel@archiver.kernel.org; Thu, 21 Apr 2022 12:27:12 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:46790) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nhYlJ-0005ym-4G; Thu, 21 Apr 2022 11:30:29 -0400 Received: from lizzy.crudebyte.com ([91.194.90.13]:59121) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nhYkw-00086e-Oi; Thu, 21 Apr 2022 11:30:24 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=crudebyte.com; s=lizzy; h=Cc:To:Subject:Date:From:References:In-Reply-To: Message-Id:Content-Type:Content-Transfer-Encoding:MIME-Version:Content-ID: Content-Description; bh=QsVY2zjD9aqJJYFr/7np1NGV5vFcJmG6mUCglu8h6ME=; b=XBy7r eBuOPQDYO/yCsEDxME3DqdBOt86tZ/4SQrGotx+erZVUMZlHbslyC3/1IcUXtUDrdb5WyezVwvwMn GOi76+1juCF9G+kHN+xf0QZSMd5gfHvKnjlQtVmXVL+8yfy/97fdseQCEtAhcL33RxMZyx1P66iNh h+nE740WRux5AdOBhqMsQxpgPUJG/IXGdF7O3N6Qgs6NkFGIceECiWopGdXv2HYoTJ59PkPbuLtLr v4D3FIcCpvoxZgjhfgON5kGIDVCky1dqB7SrsCbdazd40SCgcNCi/LvUG+umE13NbRFaV9tWLWiWI jU6qnFQ7p1OqVdg6a0zrbV0zZuxhA==; Message-Id: In-Reply-To: References: From: Christian Schoenebeck Date: Thu, 21 Apr 2022 17:07:49 +0200 Subject: [PATCH v2 4/5] 9pfs: fix wrong errno being sent to Linux client on macOS host To: qemu-devel@nongnu.org Cc: Will Cohen , Greg Kurz , Michael Roitzsch , Keno Fischer , Akihiko Odaki , qemu-stable@nongnu.org Received-SPF: none client-ip=91.194.90.13; envelope-from=eee249e308d99bb72ede83fef7bb7dc5a54ec43e@lizzy.crudebyte.com; helo=lizzy.crudebyte.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_NONE=0.001, T_SCC_BODY_TEXT_LINE=-0.01 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+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Linux and macOS only share some errno definitions with equal macro name and value. In fact most mappings for errno are completely different on the two systems. This patch converts some important errno values from macOS host to corresponding Linux errno values before eventually sending such error codes along with 'Rlerror' replies (if 9p2000.L is used that is). Not having translated errnos before violated the 9p2000.L protocol spec, which says: " size[4] Rlerror tag[2] ecode[4] ... ecode is a numerical Linux errno. " https://github.com/chaos/diod/wiki/protocol#lerror----return-error-code This patch fixes a bunch of misbehaviours when running a Linux client on macOS host. For instance this patch fixes: mount -t 9p -o posixacl ... on Linux guest if security_mode=mapped was used for 9p server, which refused to mount successfully, because macOS returned ENOATTR==93 when client tried to retrieve POSIX ACL xattrs, because errno 93 is defined as EPROTONOSUPPORT==93 on Linux, so Linux client believed that xattrs were not supported by filesystem on host in general. Signed-off-by: Christian Schoenebeck Link: https://lore.kernel.org/qemu-devel/20220421124835.3e664669@bahia/ Reviewed-by: Greg Kurz --- hw/9pfs/9p-util.h | 30 ++++++++++++++++++++++++++++++ hw/9pfs/9p.c | 2 ++ 2 files changed, 32 insertions(+) diff --git a/hw/9pfs/9p-util.h b/hw/9pfs/9p-util.h index 2cc9a5dbfb..c3526144c9 100644 --- a/hw/9pfs/9p-util.h +++ b/hw/9pfs/9p-util.h @@ -58,6 +58,36 @@ static inline uint64_t host_dev_to_dotl_dev(dev_t dev) #endif } +/* Translates errno from host -> Linux if needed */ +static inline int errno_to_dotl(int err) { +#if defined(CONFIG_LINUX) + /* nothing to translate (Linux -> Linux) */ +#elif defined(CONFIG_DARWIN) + /* + * translation mandatory for macOS hosts + * + * FIXME: Only most important errnos translated here yet, this should be + * extended to as many errnos being translated as possible in future. + */ + if (err == ENAMETOOLONG) { + err = 36; /* ==ENAMETOOLONG on Linux */ + } else if (err == ENOTEMPTY) { + err = 39; /* ==ENOTEMPTY on Linux */ + } else if (err == ELOOP) { + err = 40; /* ==ELOOP on Linux */ + } else if (err == ENOATTR) { + err = 61; /* ==ENODATA on Linux */ + } else if (err == ENOTSUP) { + err = 95; /* ==EOPNOTSUPP on Linux */ + } else if (err == EOPNOTSUPP) { + err = 95; /* ==EOPNOTSUPP on Linux */ + } +#else +#error Missing errno translation to Linux for this host system +#endif + return err; +} + #ifdef CONFIG_DARWIN #define qemu_fgetxattr(...) fgetxattr(__VA_ARGS__, 0, 0) #define qemu_lgetxattr(...) getxattr(__VA_ARGS__, 0, XATTR_NOFOLLOW) diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c index 4a296a0b94..0cd0c14c2a 100644 --- a/hw/9pfs/9p.c +++ b/hw/9pfs/9p.c @@ -1054,6 +1054,8 @@ static void coroutine_fn pdu_complete(V9fsPDU *pdu, ssize_t len) } len += ret; id = P9_RERROR; + } else { + err = errno_to_dotl(err); } ret = pdu_marshal(pdu, len, "d", err);