From nobody Thu Apr 18 03:47:10 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zoho.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1495550059758104.91922083639497; Tue, 23 May 2017 07:34:19 -0700 (PDT) Received: from localhost ([::1]:49364 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dDAt7-0003kR-BG for importer@patchew.org; Tue, 23 May 2017 10:34:17 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46353) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dDArR-0002gd-DN for qemu-devel@nongnu.org; Tue, 23 May 2017 10:32:37 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dDArN-00083o-Bd for qemu-devel@nongnu.org; Tue, 23 May 2017 10:32:33 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:48390 helo=mx0a-001b2d01.pphosted.com) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dDArN-00083X-6F for qemu-devel@nongnu.org; Tue, 23 May 2017 10:32:29 -0400 Received: from pps.filterd (m0098420.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v4NEUQ2P087664 for ; Tue, 23 May 2017 10:32:28 -0400 Received: from e34.co.us.ibm.com (e34.co.us.ibm.com [32.97.110.152]) by mx0b-001b2d01.pphosted.com with ESMTP id 2amgy026u4-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 23 May 2017 10:32:28 -0400 Received: from localhost by e34.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Tue, 23 May 2017 08:32:24 -0600 Received: from b03ledav001.gho.boulder.ibm.com (b03ledav001.gho.boulder.ibm.com [9.17.130.232]) by b03cxnp07029.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v4NEWO8i15073726; Tue, 23 May 2017 07:32:24 -0700 Received: from b03ledav001.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E0A9E6E03F; Tue, 23 May 2017 08:32:23 -0600 (MDT) Received: from bahia.lab.toulouse-stg.fr.ibm.com (unknown [9.101.4.41]) by b03ledav001.gho.boulder.ibm.com (Postfix) with ESMTP id 2F5926E03A; Tue, 23 May 2017 08:32:23 -0600 (MDT) From: Greg Kurz To: qemu-devel@nongnu.org Date: Tue, 23 May 2017 16:32:22 +0200 In-Reply-To: <149554993519.23396.2947622015408783770.stgit@bahia.lab.toulouse-stg.fr.ibm.com> References: <149554993519.23396.2947622015408783770.stgit@bahia.lab.toulouse-stg.fr.ibm.com> User-Agent: StGit/0.17.1-20-gc0b1b-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-TM-AS-GCONF: 00 x-cbid: 17052314-0016-0000-0000-000006CD3185 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00007106; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000212; SDB=6.00864511; UDB=6.00429168; IPR=6.00644291; BA=6.00005369; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00015552; XFM=3.00000015; UTC=2017-05-23 14:32:25 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17052314-0017-0000-0000-000039C5D6C5 Message-Id: <149554994233.23396.14501404339582791504.stgit@bahia.lab.toulouse-stg.fr.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-05-23_04:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=3 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1703280000 definitions=main-1705230075 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] [fuzzy] X-Received-From: 148.163.158.5 Subject: [Qemu-devel] [PATCH v2 1/4] 9pfs: check return value of v9fs_co_name_to_path() X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Leo Gaspard , Greg Kurz Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 These v9fs_co_name_to_path() call sites have always been around. I guess no care was taken to check the return value because the name_to_path operation could never fail at the time. This is no longer true: the handle and synth backends can already fail this operation, and so will the local backend soon. Signed-off-by: Greg Kurz Reviewed-by: Eric Blake --- hw/9pfs/9p.c | 36 +++++++++++++++++++++++++----------- 1 file changed, 25 insertions(+), 11 deletions(-) diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c index ab3e22f23130..57c6ed6079b1 100644 --- a/hw/9pfs/9p.c +++ b/hw/9pfs/9p.c @@ -2576,7 +2576,10 @@ static int coroutine_fn v9fs_complete_rename(V9fsPDU= *pdu, V9fsFidState *fidp, err =3D -EINVAL; goto out; } - v9fs_co_name_to_path(pdu, &dirfidp->path, name->data, &new_path); + err =3D v9fs_co_name_to_path(pdu, &dirfidp->path, name->data, &new= _path); + if (err < 0) { + goto out; + } } else { old_name =3D fidp->path.data; end =3D strrchr(old_name, '/'); @@ -2588,8 +2591,11 @@ static int coroutine_fn v9fs_complete_rename(V9fsPDU= *pdu, V9fsFidState *fidp, new_name =3D g_malloc0(end - old_name + name->size + 1); strncat(new_name, old_name, end - old_name); strncat(new_name + (end - old_name), name->data, name->size); - v9fs_co_name_to_path(pdu, NULL, new_name, &new_path); + err =3D v9fs_co_name_to_path(pdu, NULL, new_name, &new_path); g_free(new_name); + if (err < 0) { + goto out; + } } err =3D v9fs_co_rename(pdu, &fidp->path, &new_path); if (err < 0) { @@ -2669,20 +2675,26 @@ out_nofid: v9fs_string_free(&name); } =20 -static void coroutine_fn v9fs_fix_fid_paths(V9fsPDU *pdu, V9fsPath *olddir, - V9fsString *old_name, - V9fsPath *newdir, - V9fsString *new_name) +static int coroutine_fn v9fs_fix_fid_paths(V9fsPDU *pdu, V9fsPath *olddir, + V9fsString *old_name, + V9fsPath *newdir, + V9fsString *new_name) { V9fsFidState *tfidp; V9fsPath oldpath, newpath; V9fsState *s =3D pdu->s; - + int err; =20 v9fs_path_init(&oldpath); v9fs_path_init(&newpath); - v9fs_co_name_to_path(pdu, olddir, old_name->data, &oldpath); - v9fs_co_name_to_path(pdu, newdir, new_name->data, &newpath); + err =3D v9fs_co_name_to_path(pdu, olddir, old_name->data, &oldpath); + if (err < 0) { + goto out; + } + err =3D v9fs_co_name_to_path(pdu, newdir, new_name->data, &newpath); + if (err < 0) { + goto out; + } =20 /* * Fixup fid's pointing to the old name to @@ -2694,8 +2706,10 @@ static void coroutine_fn v9fs_fix_fid_paths(V9fsPDU = *pdu, V9fsPath *olddir, v9fs_fix_path(&tfidp->path, &newpath, strlen(oldpath.data)); } } +out: v9fs_path_free(&oldpath); v9fs_path_free(&newpath); + return err; } =20 static int coroutine_fn v9fs_complete_renameat(V9fsPDU *pdu, int32_t olddi= rfid, @@ -2729,8 +2743,8 @@ static int coroutine_fn v9fs_complete_renameat(V9fsPD= U *pdu, int32_t olddirfid, } if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) { /* Only for path based fid we need to do the below fixup */ - v9fs_fix_fid_paths(pdu, &olddirfidp->path, old_name, - &newdirfidp->path, new_name); + err =3D v9fs_fix_fid_paths(pdu, &olddirfidp->path, old_name, + &newdirfidp->path, new_name); } out: if (olddirfidp) { From nobody Thu Apr 18 03:47:10 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zoho.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1495550351350465.73281864724026; Tue, 23 May 2017 07:39:11 -0700 (PDT) Received: from localhost ([::1]:49396 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dDAxp-00085y-Op for importer@patchew.org; Tue, 23 May 2017 10:39:09 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46395) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dDArX-0002nv-JF for qemu-devel@nongnu.org; Tue, 23 May 2017 10:32:43 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dDArT-00088J-G8 for qemu-devel@nongnu.org; Tue, 23 May 2017 10:32:39 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:51932 helo=mx0a-001b2d01.pphosted.com) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dDArT-00087R-AL for qemu-devel@nongnu.org; Tue, 23 May 2017 10:32:35 -0400 Received: from pps.filterd (m0098414.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v4NETvMa085409 for ; Tue, 23 May 2017 10:32:34 -0400 Received: from e34.co.us.ibm.com (e34.co.us.ibm.com [32.97.110.152]) by mx0b-001b2d01.pphosted.com with ESMTP id 2am85fdg0r-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 23 May 2017 10:32:34 -0400 Received: from localhost by e34.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Tue, 23 May 2017 08:32:31 -0600 Received: from b03ledav006.gho.boulder.ibm.com (b03ledav006.gho.boulder.ibm.com [9.17.130.237]) by b03cxnp08028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v4NEWV8914549290; Tue, 23 May 2017 07:32:31 -0700 Received: from b03ledav006.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E5AE2C6037; Tue, 23 May 2017 08:32:30 -0600 (MDT) Received: from bahia.lab.toulouse-stg.fr.ibm.com (unknown [9.101.4.41]) by b03ledav006.gho.boulder.ibm.com (Postfix) with ESMTP id 18902C604A; Tue, 23 May 2017 08:32:29 -0600 (MDT) From: Greg Kurz To: qemu-devel@nongnu.org Date: Tue, 23 May 2017 16:32:29 +0200 In-Reply-To: <149554993519.23396.2947622015408783770.stgit@bahia.lab.toulouse-stg.fr.ibm.com> References: <149554993519.23396.2947622015408783770.stgit@bahia.lab.toulouse-stg.fr.ibm.com> User-Agent: StGit/0.17.1-20-gc0b1b-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-TM-AS-GCONF: 00 x-cbid: 17052314-0016-0000-0000-000006CD319D X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00007106; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000212; SDB=6.00864511; UDB=6.00429168; IPR=6.00644291; BA=6.00005369; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00015552; XFM=3.00000015; UTC=2017-05-23 14:32:32 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17052314-0017-0000-0000-000039C5D6FC Message-Id: <149554994914.23396.9158086745678389330.stgit@bahia.lab.toulouse-stg.fr.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-05-23_04:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=3 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1703280000 definitions=main-1705230075 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] [fuzzy] X-Received-From: 148.163.158.5 Subject: [Qemu-devel] [PATCH v2 2/4] 9pfs: local: resolve special directories in paths X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Leo Gaspard , Greg Kurz Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 When using the mapped-file security mode, the creds of a path /foo/bar are stored in the /foo/.virtfs_metadata/bar file. This is okay for all paths unless they end with '.' or '..', because we cannot create the corresponding file in the metadata directory. This patch ensures that '.' and '..' are resolved in all paths. The core code only passes path elements (no '/') to the backend, with the notable exception of the '/' path, which refers to the virtfs root. This patch preserves the current behavior of converting it to '.' so that it can be passed to "*at()" syscalls ('/' would mean the host root). Signed-off-by: Greg Kurz Reviewed-by: Eric Blake --- v2: - grammatical fix in the changelog - updated comment to mention that symlink resolution happens in the client --- hw/9pfs/9p-local.c | 32 +++++++++++++++++++++++++------- 1 file changed, 25 insertions(+), 7 deletions(-) diff --git a/hw/9pfs/9p-local.c b/hw/9pfs/9p-local.c index a2486566afb7..4da77ef1bc35 100644 --- a/hw/9pfs/9p-local.c +++ b/hw/9pfs/9p-local.c @@ -1138,14 +1138,32 @@ static int local_name_to_path(FsContext *ctx, V9fsP= ath *dir_path, } =20 if (dir_path) { - v9fs_path_sprintf(target, "%s/%s", dir_path->data, name); - } else if (strcmp(name, "/")) { - v9fs_path_sprintf(target, "%s", name); + if (!strcmp(name, ".")) { + /* "." relative to "foo/bar" is "foo/bar" */ + v9fs_path_copy(target, dir_path); + } else if (!strcmp(name, "..")) { + if (!strcmp(dir_path->data, ".")) { + /* ".." relative to the root is "." */ + v9fs_path_sprintf(target, "."); + } else { + char *tmp =3D g_path_get_dirname(dir_path->data); + /* Symbolic links are resolved by the client. We can assume + * that ".." relative to "foo/bar" is equivalent to "foo" + */ + v9fs_path_sprintf(target, "%s", tmp); + g_free(tmp); + } + } else { + assert(!strchr(name, '/')); + v9fs_path_sprintf(target, "%s/%s", dir_path->data, name); + } + } else if (!strcmp(name, "/") || !strcmp(name, ".") || + !strcmp(name, "..")) { + /* This is the root fid */ + v9fs_path_sprintf(target, "."); } else { - /* We want the path of the export root to be relative, otherwise - * "*at()" syscalls would treat it as "/" in the host. - */ - v9fs_path_sprintf(target, "%s", "."); + assert(!strchr(name, '/')); + v9fs_path_sprintf(target, "./%s", name); } return 0; } From nobody Thu Apr 18 03:47:10 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zoho.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1495550080595638.3759408222147; Tue, 23 May 2017 07:34:40 -0700 (PDT) Received: from localhost ([::1]:49366 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dDAtR-000400-8e for importer@patchew.org; Tue, 23 May 2017 10:34:37 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46429) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dDArf-0002sd-PP for qemu-devel@nongnu.org; Tue, 23 May 2017 10:32:48 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dDArb-0008Ie-Ma for qemu-devel@nongnu.org; Tue, 23 May 2017 10:32:47 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:42938) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dDArb-0008H3-Cy for qemu-devel@nongnu.org; Tue, 23 May 2017 10:32:43 -0400 Received: from pps.filterd (m0098409.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v4NEUQCC006252 for ; Tue, 23 May 2017 10:32:42 -0400 Received: from e18.ny.us.ibm.com (e18.ny.us.ibm.com [129.33.205.208]) by mx0a-001b2d01.pphosted.com with ESMTP id 2am9af3k9b-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 23 May 2017 10:32:41 -0400 Received: from localhost by e18.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 23 May 2017 10:32:40 -0400 Received: from b01cxnp22035.gho.pok.ibm.com (9.57.198.25) by e18.ny.us.ibm.com (146.89.104.205) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Tue, 23 May 2017 10:32:37 -0400 Received: from b01ledav003.gho.pok.ibm.com (b01ledav003.gho.pok.ibm.com [9.57.199.108]) by b01cxnp22035.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v4NEWbUU65339526; Tue, 23 May 2017 14:32:37 GMT Received: from b01ledav003.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id F31D0FA041; Tue, 23 May 2017 10:30:14 -0400 (EDT) Received: from bahia.lab.toulouse-stg.fr.ibm.com (unknown [9.101.4.41]) by b01ledav003.gho.pok.ibm.com (Postfix) with ESMTP id 7654E13A00D; Tue, 23 May 2017 10:30:14 -0400 (EDT) From: Greg Kurz To: qemu-devel@nongnu.org Date: Tue, 23 May 2017 16:32:36 +0200 In-Reply-To: <149554993519.23396.2947622015408783770.stgit@bahia.lab.toulouse-stg.fr.ibm.com> References: <149554993519.23396.2947622015408783770.stgit@bahia.lab.toulouse-stg.fr.ibm.com> User-Agent: StGit/0.17.1-20-gc0b1b-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-TM-AS-GCONF: 00 x-cbid: 17052314-0044-0000-0000-000003366304 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00007106; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000212; SDB=6.00864511; UDB=6.00429168; IPR=6.00644290; BA=6.00005369; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00015552; XFM=3.00000015; UTC=2017-05-23 14:32:39 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17052314-0045-0000-0000-0000076470B7 Message-Id: <149554995611.23396.9322039196246265398.stgit@bahia.lab.toulouse-stg.fr.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-05-23_04:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=3 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1703280000 definitions=main-1705230075 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] [fuzzy] X-Received-From: 148.163.156.1 Subject: [Qemu-devel] [PATCH v2 3/4] 9pfs: local: simplify file opening X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Leo Gaspard , Greg Kurz Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 The logic to open a path currently sits between local_open_nofollow() and the relative_openat_nofollow() helper, which has no other user. For the sake of clarity, this patch moves all the code of the helper into its unique caller. While here we also: - drop the code to skip leading "/" because the backend isn't supposed to pass anything but relative paths without consecutive slashes. The assert() is kept because we really don't want a buggy backend to pass an absolute path to openat(). - use strchrnul() to get a simpler code. This is ok since virtfs if for linux+glibc hosts only. - don't dup() the initial directory and add an assert() to ensure we don't return the global mountfd to the caller. BTW, this would mean that the caller passed an empty path, which isn't supposed to happen either. Signed-off-by: Greg Kurz Reviewed-by: Eric Blake --- v2: - rewrite logic directly in local_open_nofollow() --- hw/9pfs/9p-local.c | 34 +++++++++++++++++++++++++++++----- hw/9pfs/9p-util.c | 43 ------------------------------------------- hw/9pfs/9p-util.h | 2 -- 3 files changed, 29 insertions(+), 50 deletions(-) diff --git a/hw/9pfs/9p-local.c b/hw/9pfs/9p-local.c index 4da77ef1bc35..b30f68f91026 100644 --- a/hw/9pfs/9p-local.c +++ b/hw/9pfs/9p-local.c @@ -53,13 +53,37 @@ int local_open_nofollow(FsContext *fs_ctx, const char *= path, int flags, mode_t mode) { LocalData *data =3D fs_ctx->private; - - /* All paths are relative to the path data->mountfd points to */ - while (*path =3D=3D '/') { - path++; + int fd =3D data->mountfd; + + while (*path && fd !=3D -1) { + const char *c; + int next_fd; + char *head; + + /* Only relative paths without consecutive slashes */ + assert(*path !=3D '/'); + + head =3D g_strdup(path); + c =3D strchrnul(path, '/'); + if (*c) { + /* Intermediate path element */ + head[c - path] =3D 0; + path =3D c + 1; + next_fd =3D openat_dir(fd, head); + } else { + /* Rightmost path element */ + next_fd =3D openat_file(fd, head, flags, mode); + path =3D c; + } + g_free(head); + if (fd !=3D data->mountfd) { + close_preserve_errno(fd); + } + fd =3D next_fd; } =20 - return relative_openat_nofollow(data->mountfd, path, flags, mode); + assert(fd !=3D data->mountfd); + return fd; } =20 int local_opendir_nofollow(FsContext *fs_ctx, const char *path) diff --git a/hw/9pfs/9p-util.c b/hw/9pfs/9p-util.c index fdb4d5737635..f709c27a1fbd 100644 --- a/hw/9pfs/9p-util.c +++ b/hw/9pfs/9p-util.c @@ -14,49 +14,6 @@ #include "qemu/xattr.h" #include "9p-util.h" =20 -int relative_openat_nofollow(int dirfd, const char *path, int flags, - mode_t mode) -{ - int fd; - - fd =3D dup(dirfd); - if (fd =3D=3D -1) { - return -1; - } - - while (*path) { - const char *c; - int next_fd; - char *head; - - /* Only relative paths without consecutive slashes */ - assert(path[0] !=3D '/'); - - head =3D g_strdup(path); - c =3D strchr(path, '/'); - if (c) { - head[c - path] =3D 0; - next_fd =3D openat_dir(fd, head); - } else { - next_fd =3D openat_file(fd, head, flags, mode); - } - g_free(head); - if (next_fd =3D=3D -1) { - close_preserve_errno(fd); - return -1; - } - close(fd); - fd =3D next_fd; - - if (!c) { - break; - } - path =3D c + 1; - } - - return fd; -} - ssize_t fgetxattrat_nofollow(int dirfd, const char *filename, const char *= name, void *value, size_t size) { diff --git a/hw/9pfs/9p-util.h b/hw/9pfs/9p-util.h index 517027c52032..91299a24b8af 100644 --- a/hw/9pfs/9p-util.h +++ b/hw/9pfs/9p-util.h @@ -50,8 +50,6 @@ static inline int openat_file(int dirfd, const char *name= , int flags, return fd; } =20 -int relative_openat_nofollow(int dirfd, const char *path, int flags, - mode_t mode); ssize_t fgetxattrat_nofollow(int dirfd, const char *path, const char *name, void *value, size_t size); int fsetxattrat_nofollow(int dirfd, const char *path, const char *name, From nobody Thu Apr 18 03:47:10 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zoho.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1495550088187509.42511037985923; Tue, 23 May 2017 07:34:48 -0700 (PDT) Received: from localhost ([::1]:49367 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dDAta-00048d-Kw for importer@patchew.org; Tue, 23 May 2017 10:34:46 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46446) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dDArl-0002wp-0v for qemu-devel@nongnu.org; Tue, 23 May 2017 10:32:57 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dDArg-0008Lo-Oi for qemu-devel@nongnu.org; Tue, 23 May 2017 10:32:53 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:49316 helo=mx0a-001b2d01.pphosted.com) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dDArg-0008Lg-I1 for qemu-devel@nongnu.org; Tue, 23 May 2017 10:32:48 -0400 Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v4NETe8v017089 for ; Tue, 23 May 2017 10:32:47 -0400 Received: from e14.ny.us.ibm.com (e14.ny.us.ibm.com [129.33.205.204]) by mx0b-001b2d01.pphosted.com with ESMTP id 2amf9axqjn-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 23 May 2017 10:32:47 -0400 Received: from localhost by e14.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Tue, 23 May 2017 10:32:43 -0400 Received: from b01ledav001.gho.pok.ibm.com (b01ledav001.gho.pok.ibm.com [9.57.199.106]) by b01cxnp23032.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v4NEWiRj40567020; Tue, 23 May 2017 14:32:44 GMT Received: from b01ledav001.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 1DE3028041; Tue, 23 May 2017 10:32:38 -0400 (EDT) Received: from bahia.lab.toulouse-stg.fr.ibm.com (unknown [9.101.4.41]) by b01ledav001.gho.pok.ibm.com (Postfix) with ESMTP id 96F492803E; Tue, 23 May 2017 10:32:37 -0400 (EDT) From: Greg Kurz To: qemu-devel@nongnu.org Date: Tue, 23 May 2017 16:32:42 +0200 In-Reply-To: <149554993519.23396.2947622015408783770.stgit@bahia.lab.toulouse-stg.fr.ibm.com> References: <149554993519.23396.2947622015408783770.stgit@bahia.lab.toulouse-stg.fr.ibm.com> User-Agent: StGit/0.17.1-20-gc0b1b-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-TM-AS-GCONF: 00 x-cbid: 17052314-0052-0000-0000-00000208018A X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00007106; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000212; SDB=6.00864511; UDB=6.00429167; IPR=6.00644291; BA=6.00005369; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00015552; XFM=3.00000015; UTC=2017-05-23 14:32:45 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17052314-0053-0000-0000-000050AE6C95 Message-Id: <149554996230.23396.14573553304393992709.stgit@bahia.lab.toulouse-stg.fr.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-05-23_04:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=1 malwarescore=0 phishscore=0 adultscore=1 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1703280000 definitions=main-1705230075 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] [fuzzy] X-Received-From: 148.163.158.5 Subject: [Qemu-devel] [PATCH v2 4/4] 9pfs: local: metadata file for the VirtFS root X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Leo Gaspard , Greg Kurz Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 When using the mapped-file security, credentials are stored in a metadata directory located in the parent directory. This is okay for all paths with the notable exception of the root path, since we don't want and probably can't create a metadata directory above the virtfs directory on the host. This patch introduces a dedicated metadata file, sitting in the virtfs root for this purpose. It relies on the fact that the "." name necessarily refers to the virtfs root. As for the metadata directory, we don't want the client to see this file. The current code only cares for readdir() but there are many other places to fix actually. The filtering logic is hence put in a separate function. Before: # ls -ld drwxr-xr-x. 3 greg greg 4096 May 5 12:49 . # chown root.root . chown: changing ownership of '.': Is a directory # ls -ld drwxr-xr-x. 3 greg greg 4096 May 5 12:49 . After: # ls -ld drwxr-xr-x. 3 greg greg 4096 May 5 12:49 . # chown root.root . # ls -ld drwxr-xr-x. 3 root root 4096 May 5 12:50 . and from the host: ls -al .virtfs_metadata_root -rwx------. 1 greg greg 26 May 5 12:50 .virtfs_metadata_root $ cat .virtfs_metadata_root virtfs.uid=3D0 virtfs.gid=3D0 Reported-by: Leo Gaspard Signed-off-by: Greg Kurz Reviewed-by: Eric Blake --- v2: - changed metadata file mode bits to 0600 - fixed typo in commit message - rebased --- hw/9pfs/9p-local.c | 81 +++++++++++++++++++++++++++++++++++-------------= ---- 1 file changed, 54 insertions(+), 27 deletions(-) diff --git a/hw/9pfs/9p-local.c b/hw/9pfs/9p-local.c index b30f68f91026..8babd5542f06 100644 --- a/hw/9pfs/9p-local.c +++ b/hw/9pfs/9p-local.c @@ -107,6 +107,7 @@ static void unlinkat_preserve_errno(int dirfd, const ch= ar *path, int flags) } =20 #define VIRTFS_META_DIR ".virtfs_metadata" +#define VIRTFS_META_ROOT_FILE VIRTFS_META_DIR "_root" =20 static FILE *local_fopenat(int dirfd, const char *name, const char *mode) { @@ -143,13 +144,17 @@ static void local_mapped_file_attr(int dirfd, const c= har *name, char buf[ATTR_MAX]; int map_dirfd; =20 - map_dirfd =3D openat_dir(dirfd, VIRTFS_META_DIR); - if (map_dirfd =3D=3D -1) { - return; - } + if (strcmp(name, ".")) { + map_dirfd =3D openat_dir(dirfd, VIRTFS_META_DIR); + if (map_dirfd =3D=3D -1) { + return; + } =20 - fp =3D local_fopenat(map_dirfd, name, "r"); - close_preserve_errno(map_dirfd); + fp =3D local_fopenat(map_dirfd, name, "r"); + close_preserve_errno(map_dirfd); + } else { + fp =3D local_fopenat(dirfd, VIRTFS_META_ROOT_FILE, "r"); + } if (!fp) { return; } @@ -227,26 +232,38 @@ static int local_set_mapped_file_attrat(int dirfd, co= nst char *name, int ret; char buf[ATTR_MAX]; int uid =3D -1, gid =3D -1, mode =3D -1, rdev =3D -1; - int map_dirfd; - - ret =3D mkdirat(dirfd, VIRTFS_META_DIR, 0700); - if (ret < 0 && errno !=3D EEXIST) { - return -1; - } - - map_dirfd =3D openat_dir(dirfd, VIRTFS_META_DIR); - if (map_dirfd =3D=3D -1) { - return -1; - } + int map_dirfd, map_fd; + bool is_root =3D !strcmp(name, "."); + + if (is_root) { + fp =3D local_fopenat(dirfd, VIRTFS_META_ROOT_FILE, "r"); + if (!fp) { + if (errno =3D=3D ENOENT) { + goto update_map_file; + } else { + return -1; + } + } + } else { + ret =3D mkdirat(dirfd, VIRTFS_META_DIR, 0700); + if (ret < 0 && errno !=3D EEXIST) { + return -1; + } =20 - fp =3D local_fopenat(map_dirfd, name, "r"); - if (!fp) { - if (errno =3D=3D ENOENT) { - goto update_map_file; - } else { - close_preserve_errno(map_dirfd); + map_dirfd =3D openat_dir(dirfd, VIRTFS_META_DIR); + if (map_dirfd =3D=3D -1) { return -1; } + + fp =3D local_fopenat(map_dirfd, name, "r"); + if (!fp) { + if (errno =3D=3D ENOENT) { + goto update_map_file; + } else { + close_preserve_errno(map_dirfd); + return -1; + } + } } memset(buf, 0, ATTR_MAX); while (fgets(buf, ATTR_MAX, fp)) { @@ -264,12 +281,21 @@ static int local_set_mapped_file_attrat(int dirfd, co= nst char *name, fclose(fp); =20 update_map_file: - fp =3D local_fopenat(map_dirfd, name, "w"); - close_preserve_errno(map_dirfd); + if (is_root) { + fp =3D local_fopenat(dirfd, VIRTFS_META_ROOT_FILE, "w"); + } else { + fp =3D local_fopenat(map_dirfd, name, "w"); + close_preserve_errno(map_dirfd); + } if (!fp) { return -1; } =20 + map_fd =3D fileno(fp); + assert(map_fd !=3D -1); + ret =3D fchmod(map_fd, 0600); + assert(ret =3D=3D 0); + if (credp->fc_uid !=3D -1) { uid =3D credp->fc_uid; } @@ -478,7 +504,8 @@ static off_t local_telldir(FsContext *ctx, V9fsFidOpenS= tate *fs) =20 static bool local_is_mapped_file_metadata(FsContext *fs_ctx, const char *n= ame) { - return !strcmp(name, VIRTFS_META_DIR); + return + !strcmp(name, VIRTFS_META_DIR) || !strcmp(name, VIRTFS_META_ROOT_F= ILE); } =20 static struct dirent *local_readdir(FsContext *ctx, V9fsFidOpenState *fs) @@ -495,7 +522,7 @@ again: entry->d_type =3D DT_UNKNOWN; } else if (ctx->export_flags & V9FS_SM_MAPPED_FILE) { if (local_is_mapped_file_metadata(ctx, entry->d_name)) { - /* skip the meta data directory */ + /* skip the meta data */ goto again; } entry->d_type =3D DT_UNKNOWN;