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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 73789C4332F for ; Thu, 23 Dec 2021 23:52:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245211AbhLWXwF (ORCPT ); Thu, 23 Dec 2021 18:52:05 -0500 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:50146 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245202AbhLWXwF (ORCPT ); Thu, 23 Dec 2021 18:52:05 -0500 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 1BNIxpV8001525 for ; Thu, 23 Dec 2021 15:52:05 -0800 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=uk7IFNmdtErUYMGvrYmd+1ahvezsWq45jWkRwFAqZkY=; b=mE5OCX8j3cYBQnCs5/sQp5ffzZksFkVE0I7X35DFOnD9QpGbSnH0AibRA54inNrMIswM QQTJYQt8nyniWJOADa5EnKlgIYrqRCrNL/eaF4o4ljP/iIu7I//qnp1qyD7cykwzOtwg 0gsqdFeVGOyY/tZHofBbihR7/EduCGl8T1Q= Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3d4ftd6uq2-5 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 23 Dec 2021 15:52:05 -0800 Received: from twshared7572.23.frc3.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:83::6) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Thu, 23 Dec 2021 15:52:02 -0800 Received: by devvm225.atn0.facebook.com (Postfix, from userid 425415) id 73B6D87DF60E; Thu, 23 Dec 2021 15:51:55 -0800 (PST) From: Stefan Roesch To: , , CC: , , Subject: [PATCH v8 2/5] fs: split off setxattr_copy and do_setxattr function from setxattr Date: Thu, 23 Dec 2021 15:51:20 -0800 Message-ID: <20211223235123.4092764-3-shr@fb.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20211223235123.4092764-1-shr@fb.com> References: <20211223235123.4092764-1-shr@fb.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-FB-Internal: Safe Content-Type: text/plain X-Proofpoint-ORIG-GUID: aX70rDc62n6xT0RU0FUDVx0aZPJsNDCn X-Proofpoint-GUID: aX70rDc62n6xT0RU0FUDVx0aZPJsNDCn X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.790,Hydra:6.0.425,FMLib:17.11.62.513 definitions=2021-12-23_04,2021-12-22_01,2021-12-02_01 X-Proofpoint-Spam-Details: rule=fb_outbound_notspam policy=fb_outbound score=0 bulkscore=0 lowpriorityscore=0 mlxlogscore=999 impostorscore=0 clxscore=1015 phishscore=0 mlxscore=0 adultscore=0 priorityscore=1501 spamscore=0 suspectscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2110150000 definitions=main-2112230122 X-FB-Internal: deliver Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org This splits of the setup part of the function setxattr in its own dedicated function called setxattr_copy. In addition it also exposes a new function called do_setxattr for making the setxattr call. This makes it possible to call these two functions from io_uring in the processing of an xattr request. Signed-off-by: Stefan Roesch --- fs/internal.h | 22 +++++++++++++ fs/xattr.c | 87 ++++++++++++++++++++++++++++++++++++++------------- 2 files changed, 87 insertions(+), 22 deletions(-) diff --git a/fs/internal.h b/fs/internal.h index 432ea3ce76ec..b07df1623de6 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -202,3 +202,25 @@ struct linux_dirent64; =20 int vfs_getdents(struct file *file, struct linux_dirent64 __user *dirent= , unsigned int count, loff_t *pos); + + /* + * fs/xattr.c: + */ +struct xattr_name { + char name[XATTR_NAME_MAX + 1]; +}; + +struct xattr_ctx { + /* Value of attribute */ + const void __user *value; + size_t size; + /* Attribute name */ + struct xattr_name *kname; + unsigned int flags; +}; + + +int setxattr_copy(const char __user *name, struct xattr_ctx *ctx, + void **xattr_val); +int do_setxattr(struct user_namespace *mnt_userns, struct dentry *dentry= , + struct xattr_ctx *ctx, void *xattr_val); diff --git a/fs/xattr.c b/fs/xattr.c index 5c8c5175b385..dcb4f0ff7e6e 100644 --- a/fs/xattr.c +++ b/fs/xattr.c @@ -25,6 +25,8 @@ =20 #include =20 +#include "internal.h" + static const char * strcmp_prefix(const char *a, const char *a_prefix) { @@ -539,43 +541,84 @@ EXPORT_SYMBOL_GPL(vfs_removexattr); /* * Extended attribute SET operations */ -static long -setxattr(struct user_namespace *mnt_userns, struct dentry *d, - const char __user *name, const void __user *value, size_t size, - int flags) + +int setxattr_copy(const char __user *name, struct xattr_ctx *ctx, + void **xattr_val) { - int error; void *kvalue =3D NULL; - char kname[XATTR_NAME_MAX + 1]; + int error; =20 - if (flags & ~(XATTR_CREATE|XATTR_REPLACE)) + if (ctx->flags & ~(XATTR_CREATE|XATTR_REPLACE)) return -EINVAL; =20 - error =3D strncpy_from_user(kname, name, sizeof(kname)); - if (error =3D=3D 0 || error =3D=3D sizeof(kname)) - error =3D -ERANGE; + error =3D strncpy_from_user(ctx->kname->name, name, + sizeof(ctx->kname->name)); + if (error =3D=3D 0 || error =3D=3D sizeof(ctx->kname->name)) + return -ERANGE; if (error < 0) return error; =20 - if (size) { - if (size > XATTR_SIZE_MAX) + if (ctx->size) { + if (ctx->size > XATTR_SIZE_MAX) return -E2BIG; - kvalue =3D kvmalloc(size, GFP_KERNEL); + + kvalue =3D kvmalloc(ctx->size, GFP_KERNEL); if (!kvalue) return -ENOMEM; - if (copy_from_user(kvalue, value, size)) { - error =3D -EFAULT; - goto out; + + if (copy_from_user(kvalue, ctx->value, ctx->size)) { + kvfree(kvalue); + return -EFAULT; } - if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) =3D=3D 0) || - (strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) =3D=3D 0)) - posix_acl_fix_xattr_from_user(mnt_userns, kvalue, size); } =20 - error =3D vfs_setxattr(mnt_userns, d, kname, kvalue, size, flags); -out: - kvfree(kvalue); + *xattr_val =3D kvalue; + return 0; +} + +static void setxattr_convert(struct user_namespace *mnt_userns, + struct xattr_ctx *ctx, void *xattr_value) +{ + if (ctx->size && + ((strcmp(ctx->kname->name, XATTR_NAME_POSIX_ACL_ACCESS) =3D=3D 0) || + (strcmp(ctx->kname->name, XATTR_NAME_POSIX_ACL_DEFAULT) =3D=3D 0))) + posix_acl_fix_xattr_from_user(mnt_userns, xattr_value, ctx->size); +} + +int do_setxattr(struct user_namespace *mnt_userns, struct dentry *dentry= , + struct xattr_ctx *ctx, void *xattr_value) +{ + int error; + + setxattr_convert(mnt_userns, ctx, xattr_value); + error =3D vfs_setxattr(mnt_userns, dentry, ctx->kname->name, + xattr_value, ctx->size, ctx->flags); + + return error; +} + +static long +setxattr(struct user_namespace *mnt_userns, struct dentry *d, + const char __user *name, const void __user *value, size_t size, + int flags) +{ + struct xattr_name kname; + struct xattr_ctx ctx =3D { + .value =3D value, + .size =3D size, + .kname =3D &kname, + .flags =3D flags, + }; + void *xattr_value =3D NULL; + int error; + + error =3D setxattr_copy(name, &ctx, &xattr_value); + if (error) + return error; + + error =3D do_setxattr(mnt_userns, d, &ctx, xattr_value); =20 + kvfree(xattr_value); return error; } =20 --=20 2.30.2