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 44F2FC433EF for ; Tue, 4 Jan 2022 19:09:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232664AbiADTJu (ORCPT ); Tue, 4 Jan 2022 14:09:50 -0500 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:50730 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231343AbiADTJu (ORCPT ); Tue, 4 Jan 2022 14:09:50 -0500 Received: from pps.filterd (m0044010.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.1.2/8.16.1.2) with ESMTP id 204GFK9F019289 for ; Tue, 4 Jan 2022 11:09:50 -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=FjGxnC986xNMAOkWCTY3KciMFTTPqeyxo54ALOxZjQ0=; b=AmCtXkik+Av8m79QuFS8VNcGhT6I26aMVL+TBV9D8VPXfIGT6gmGDiHGRNnXbnPxhhnB Qk2CPmtCQ70oGZ3DC4KPH8VRkqovh/j6UzLvWZxQg4wItPOpSDwDBeJJ3Y+muEy+eCI7 noj+1dGucfieNOZzLAmTx/kucU37vUoXXeE= Received: from mail.thefacebook.com ([163.114.132.120]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3dcp6h2eqm-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Tue, 04 Jan 2022 11:09:50 -0800 Received: from twshared7572.23.frc3.facebook.com (2620:10d:c085:208::f) by mail.thefacebook.com (2620:10d:c085:11d::5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Tue, 4 Jan 2022 11:09:45 -0800 Received: by devvm225.atn0.facebook.com (Postfix, from userid 425415) id B688A8FC8E0D; Tue, 4 Jan 2022 11:09:38 -0800 (PST) From: Stefan Roesch To: , , CC: , , Subject: [PATCH v11 1/4] fs: split off setxattr_copy and do_setxattr function from setxattr Date: Tue, 4 Jan 2022 11:09:33 -0800 Message-ID: <20220104190936.3085647-2-shr@fb.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220104190936.3085647-1-shr@fb.com> References: <20220104190936.3085647-1-shr@fb.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-FB-Internal: Safe Content-Type: text/plain X-Proofpoint-GUID: RR4qOScJgGNzqOfP9xI0KSbnUP4Iu561 X-Proofpoint-ORIG-GUID: RR4qOScJgGNzqOfP9xI0KSbnUP4Iu561 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=2022-01-04_09,2022-01-04_01,2021-12-02_01 X-Proofpoint-Spam-Details: rule=fb_outbound_notspam policy=fb_outbound score=0 lowpriorityscore=0 adultscore=0 priorityscore=1501 phishscore=0 mlxlogscore=999 bulkscore=0 mlxscore=0 impostorscore=0 malwarescore=0 spamscore=0 suspectscore=0 clxscore=1015 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2110150000 definitions=main-2201040127 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 Acked-by: Christian Brauner --- fs/internal.h | 21 +++++++++++++ fs/xattr.c | 82 ++++++++++++++++++++++++++++++++++++--------------- 2 files changed, 79 insertions(+), 24 deletions(-) diff --git a/fs/internal.h b/fs/internal.h index 432ea3ce76ec..00c98b0cd634 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -202,3 +202,24 @@ 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; + void *kvalue; + size_t size; + /* Attribute name */ + struct xattr_name *kname; + unsigned int flags; +}; + +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 5c8c5175b385..dec7ac3e0e89 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 +541,75 @@ 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) { int error; - void *kvalue =3D NULL; - char kname[XATTR_NAME_MAX + 1]; =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) + error =3D 0; + if (ctx->size) { + if (ctx->size > XATTR_SIZE_MAX) return -E2BIG; - kvalue =3D kvmalloc(size, GFP_KERNEL); - if (!kvalue) - return -ENOMEM; - if (copy_from_user(kvalue, value, size)) { - error =3D -EFAULT; - goto out; + + ctx->kvalue =3D vmemdup_user(ctx->value, ctx->size); + if (IS_ERR(ctx->kvalue)) { + error =3D PTR_ERR(ctx->kvalue); + ctx->kvalue =3D NULL; } - 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); + return error; +} + +static void setxattr_convert(struct user_namespace *mnt_userns, + struct xattr_ctx *ctx) +{ + 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, ctx->kvalue, ctx->size); +} + +int do_setxattr(struct user_namespace *mnt_userns, struct dentry *dentry= , + struct xattr_ctx *ctx) +{ + setxattr_convert(mnt_userns, ctx); + return vfs_setxattr(mnt_userns, dentry, ctx->kname->name, + ctx->kvalue, ctx->size, ctx->flags); +} + +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, + .kvalue =3D NULL, + .size =3D size, + .kname =3D &kname, + .flags =3D flags, + }; + int error; + + error =3D setxattr_copy(name, &ctx); + if (error) + return error; + + error =3D do_setxattr(mnt_userns, d, &ctx); =20 + kvfree(ctx.kvalue); return error; } =20 --=20 2.30.2