From patchwork Wed Mar 23 15:44:18 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Roesch X-Patchwork-Id: 12789853 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 696E9C4332F for ; Wed, 23 Mar 2022 15:44:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243424AbiCWPqK (ORCPT ); Wed, 23 Mar 2022 11:46:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38324 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244437AbiCWPqE (ORCPT ); Wed, 23 Mar 2022 11:46:04 -0400 Received: from mx0a-00082601.pphosted.com (mx0a-00082601.pphosted.com [67.231.145.42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 22ABF3BF94 for ; Wed, 23 Mar 2022 08:44:35 -0700 (PDT) Received: from pps.filterd (m0109333.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.1.2/8.16.1.2) with ESMTP id 22NDenXo017075 for ; Wed, 23 Mar 2022 08:44:35 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=facebook; bh=D/jZId5oa299UGiUhVhwQtmGNBbsRd/InFeSEFlLFnc=; b=dcUkgLKcihEbwjiqEkGceT+M/1pDQ3j1EuSvk4Ej4nAhkW0ookzQf2b07CuDjKb0NDa1 8eMVyWyndunDwNOCzEO7J5dkU/6gkVTmmsK/pyYVy5nDyLv1SoO/9jBGu2F3DsSskhye Y1YSBpaP5RoJYor/Z5depgtsQpb3k6/6i8U= Received: from mail.thefacebook.com ([163.114.132.120]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3eyc9wu3gk-6 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Wed, 23 Mar 2022 08:44:34 -0700 Received: from twshared10432.40.frc1.facebook.com (2620:10d:c085:208::f) by mail.thefacebook.com (2620:10d:c085:11d::7) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Wed, 23 Mar 2022 08:44:33 -0700 Received: by devvm225.atn0.facebook.com (Postfix, from userid 425415) id 83434CA024C7; Wed, 23 Mar 2022 08:44:22 -0700 (PDT) From: Stefan Roesch To: , , CC: , , Subject: [PATCH v13 2/4] fs: split off do_getxattr from getxattr Date: Wed, 23 Mar 2022 08:44:18 -0700 Message-ID: <20220323154420.3301504-3-shr@fb.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220323154420.3301504-1-shr@fb.com> References: <20220323154420.3301504-1-shr@fb.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-GUID: lYtV4SYtyUr8tKIMDDZ9X4H38hFT-oDI X-Proofpoint-ORIG-GUID: lYtV4SYtyUr8tKIMDDZ9X4H38hFT-oDI X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.850,Hydra:6.0.425,FMLib:17.11.64.514 definitions=2022-03-23_07,2022-03-23_01,2022-02-23_01 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org This splits off do_getxattr function from the getxattr function. This will allow io_uring to call it from its io worker. Signed-off-by: Stefan Roesch Acked-by: Christian Brauner --- fs/internal.h | 5 +++++ fs/xattr.c | 59 +++++++++++++++++++++++++++++++++------------------ 2 files changed, 43 insertions(+), 21 deletions(-) diff --git a/fs/internal.h b/fs/internal.h index 96bbab6b58ba..4a28ae13aaa4 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -217,6 +217,11 @@ struct xattr_ctx { unsigned int flags; }; + +ssize_t do_getxattr(struct user_namespace *mnt_userns, + struct dentry *d, + struct xattr_ctx *ctx); + int setxattr_copy(const char __user *name, struct xattr_ctx *ctx); int do_setxattr(struct user_namespace *mnt_userns, struct dentry *dentry, struct xattr_ctx *ctx); diff --git a/fs/xattr.c b/fs/xattr.c index 717b3904c2e5..0b9f296a7071 100644 --- a/fs/xattr.c +++ b/fs/xattr.c @@ -675,43 +675,60 @@ SYSCALL_DEFINE5(fsetxattr, int, fd, const char __user *, name, /* * Extended attribute GET operations */ -static ssize_t -getxattr(struct user_namespace *mnt_userns, struct dentry *d, - const char __user *name, void __user *value, size_t size) +ssize_t +do_getxattr(struct user_namespace *mnt_userns, struct dentry *d, + struct xattr_ctx *ctx) { ssize_t error; - void *kvalue = NULL; - char kname[XATTR_NAME_MAX + 1]; + char *kname = ctx->kname->name; - error = strncpy_from_user(kname, name, sizeof(kname)); - if (error == 0 || error == sizeof(kname)) - error = -ERANGE; - if (error < 0) - return error; - - if (size) { - if (size > XATTR_SIZE_MAX) - size = XATTR_SIZE_MAX; - kvalue = kvzalloc(size, GFP_KERNEL); - if (!kvalue) + if (ctx->size) { + if (ctx->size > XATTR_SIZE_MAX) + ctx->size = XATTR_SIZE_MAX; + ctx->kvalue = kvzalloc(ctx->size, GFP_KERNEL); + if (!ctx->kvalue) return -ENOMEM; } - error = vfs_getxattr(mnt_userns, d, kname, kvalue, size); + error = vfs_getxattr(mnt_userns, d, kname, ctx->kvalue, ctx->size); if (error > 0) { if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) || (strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0)) - posix_acl_fix_xattr_to_user(mnt_userns, kvalue, error); - if (size && copy_to_user(value, kvalue, error)) + posix_acl_fix_xattr_to_user(mnt_userns, ctx->kvalue, error); + if (ctx->size && copy_to_user(ctx->value, ctx->kvalue, error)) error = -EFAULT; - } else if (error == -ERANGE && size >= XATTR_SIZE_MAX) { + } else if (error == -ERANGE && ctx->size >= XATTR_SIZE_MAX) { /* The file system tried to returned a value bigger than XATTR_SIZE_MAX bytes. Not possible. */ error = -E2BIG; } - kvfree(kvalue); + return error; +} + +static ssize_t +getxattr(struct user_namespace *mnt_userns, struct dentry *d, + const char __user *name, void __user *value, size_t size) +{ + ssize_t error; + struct xattr_name kname; + struct xattr_ctx ctx = { + .value = value, + .kvalue = NULL, + .size = size, + .kname = &kname, + .flags = 0, + }; + + error = strncpy_from_user(kname.name, name, sizeof(kname.name)); + if (error == 0 || error == sizeof(kname.name)) + error = -ERANGE; + if (error < 0) + return error; + error = do_getxattr(mnt_userns, d, &ctx); + + kvfree(ctx.kvalue); return error; }