From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id ECC417261E; Wed, 12 Nov 2025 15:06:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762960016; cv=none; b=ZHKto4gzhhC5XT4+XKt89YYUpfBtQlB1xU1F9/ELJ1HieDz5koRkSmBLvOz2YwwfI4zo/KqYnVZJnZOz/qraCtHOJfvh0nklfbxWqQyvXArI21fHcRPm609FTjqSea/A00nK9RvTBlhao1GRa9HM0TesgIsK9vKNZnAbsDKFlWA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762960016; c=relaxed/simple; bh=Jp8GAc98lQD1XWw/NpkDMiKoitJJan/TkqVWtdcWHWE=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=Zbo1zEZLUj7I2YJuJO9DPxdODXBNP3mQ7nkXcETwbZvvItKlrAmklgx0P4iKJEvVHdzAl8qHoMXyjJtCxKkNkk9+pHdQwAe7oz859Fc8+5o8xAa1JWLpO3CTwlRSV6UxWqZTOM9E8Pam4w306q19ebnbfwoUjc8pD3Br3ayo7ws= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=VKdMzWeo; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="VKdMzWeo" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 91A27C4CEF8; Wed, 12 Nov 2025 15:06:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1762960015; bh=Jp8GAc98lQD1XWw/NpkDMiKoitJJan/TkqVWtdcWHWE=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=VKdMzWeo4USPFVKqo6E7eQMiu+MPNaNQOP+ALic4BD4idQzgKTeW3GI4JMzmdiVLQ 0Y3xjEoVjTAzgrc4xwIlEFUxLV0JL64tmrkSikoI3/ki9gl/9QArKA9n2/y4g4V72Z BJPbGvxmLelwNbIGsMuW9xvl5xTZMRoM6gjw8WEZfPEu//t4xzpURXKkT1fIGVcmHV XRbtBMsVesjxTuWh+sofrFvINo/xbHxpm62K9sHeQoGBvhOGPIfuCyYQqlKtMtNFU7 jznOCLZANhIwIDTHV1hIrX5T/tBeEYPYCGS4mtV2NmLFNjYg2DVo/+kQ6YeeCtpKnV DGVVvv4Qu/ncg== Message-ID: <9887b21b264aaf2b55f7284020b0760e69b3d0ed.camel@kernel.org> Subject: Re: [PATCH v5 09/14] VFS/nfsd/ovl: introduce start_renaming() and end_renaming() From: Jeff Layton To: NeilBrown , Alexander Viro , Christian Brauner , Amir Goldstein Cc: Jan Kara , linux-fsdevel@vger.kernel.org, Chris Mason , David Sterba , David Howells , Greg Kroah-Hartman , "Rafael J. Wysocki" , Danilo Krummrich , Tyler Hicks , Miklos Szeredi , Chuck Lever , Olga Kornievskaia , Dai Ngo , Namjae Jeon , Steve French , Sergey Senozhatsky , Carlos Maiolino , John Johansen , Paul Moore , James Morris , "Serge E. Hallyn" , Stephen Smalley , Ondrej Mosnacek , Mateusz Guzik , Lorenzo Stoakes , Stefan Berger , "Darrick J. Wong" , linux-kernel@vger.kernel.org, netfs@lists.linux.dev, ecryptfs@vger.kernel.org, linux-nfs@vger.kernel.org, linux-unionfs@vger.kernel.org, linux-cifs@vger.kernel.org, linux-xfs@vger.kernel.org, linux-security-module@vger.kernel.org, selinux@vger.kernel.org Date: Wed, 12 Nov 2025 10:06:51 -0500 In-Reply-To: <20251106005333.956321-10-neilb@ownmail.net> References: <20251106005333.956321-1-neilb@ownmail.net> <20251106005333.956321-10-neilb@ownmail.net> Autocrypt: addr=jlayton@kernel.org; prefer-encrypt=mutual; keydata=mQINBE6V0TwBEADXhJg7s8wFDwBMEvn0qyhAnzFLTOCHooMZyx7XO7dAiIhDSi7G1NPxw n8jdFUQMCR/GlpozMFlSFiZXiObE7sef9rTtM68ukUyZM4pJ9l0KjQNgDJ6Fr342Htkjxu/kFV1Wv egyjnSsFt7EGoDjdKqr1TS9syJYFjagYtvWk/UfHlW09X+jOh4vYtfX7iYSx/NfqV3W1D7EDi0PqV T2h6v8i8YqsATFPwO4nuiTmL6I40ZofxVd+9wdRI4Db8yUNA4ZSP2nqLcLtFjClYRBoJvRWvsv4lm 0OX6MYPtv76hka8lW4mnRmZqqx3UtfHX/hF/zH24Gj7A6sYKYLCU3YrI2Ogiu7/ksKcl7goQjpvtV YrOOI5VGLHge0awt7bhMCTM9KAfPc+xL/ZxAMVWd3NCk5SamL2cE99UWgtvNOIYU8m6EjTLhsj8sn VluJH0/RcxEeFbnSaswVChNSGa7mXJrTR22lRL6ZPjdMgS2Km90haWPRc8Wolcz07Y2se0xpGVLEQ cDEsvv5IMmeMe1/qLZ6NaVkNuL3WOXvxaVT9USW1+/SGipO2IpKJjeDZfehlB/kpfF24+RrK+seQf CBYyUE8QJpvTZyfUHNYldXlrjO6n5MdOempLqWpfOmcGkwnyNRBR46g/jf8KnPRwXs509yAqDB6sE LZH+yWr9LQZEwARAQABtCVKZWZmIExheXRvbiA8amxheXRvbkBwb29jaGllcmVkcy5uZXQ+iQI7BB MBAgAlAhsDBgsJCAcDAgYVCAIJCgsEFgIDAQIeAQIXgAUCTpXWPAIZAQAKCRAADmhBGVaCFc65D/4 gBLNMHopQYgG/9RIM3kgFCCQV0pLv0hcg1cjr+bPI5f1PzJoOVi9s0wBDHwp8+vtHgYhM54yt43uI 7Htij0RHFL5eFqoVT4TSfAg2qlvNemJEOY0e4daljjmZM7UtmpGs9NN0r9r50W82eb5Kw5bc/r0km R/arUS2st+ecRsCnwAOj6HiURwIgfDMHGPtSkoPpu3DDp/cjcYUg3HaOJuTjtGHFH963B+f+hyQ2B rQZBBE76ErgTDJ2Db9Ey0kw7VEZ4I2nnVUY9B5dE2pJFVO5HJBMp30fUGKvwaKqYCU2iAKxdmJXRI ONb7dSde8LqZahuunPDMZyMA5+mkQl7kpIpR6kVDIiqmxzRuPeiMP7O2FCUlS2DnJnRVrHmCljLkZ Wf7ZUA22wJpepBligemtSRSbqCyZ3B48zJ8g5B8xLEntPo/NknSJaYRvfEQqGxgk5kkNWMIMDkfQO lDSXZvoxqU9wFH/9jTv1/6p8dHeGM0BsbBLMqQaqnWiVt5mG92E1zkOW69LnoozE6Le+12DsNW7Rj iR5K+27MObjXEYIW7FIvNN/TQ6U1EOsdxwB8o//Yfc3p2QqPr5uS93SDDan5ehH59BnHpguTc27Xi QQZ9EGiieCUx6Zh2ze3X2UW9YNzE15uKwkkuEIj60NvQRmEDfweYfOfPVOueC+iFifbQgSmVmZiBM YXl0b24gPGpsYXl0b25AcmVkaGF0LmNvbT6JAjgEEwECACIFAk6V0q0CGwMGCwkIBwMCBhUIAgkKC wQWAgMBAh4BAheAAAoJEAAOaEEZVoIViKUQALpvsacTMWWOd7SlPFzIYy2/fjvKlfB/Xs4YdNcf9q LqF+lk2RBUHdR/dGwZpvw/OLmnZ8TryDo2zXVJNWEEUFNc7wQpl3i78r6UU/GUY/RQmOgPhs3epQC 3PMJj4xFx+VuVcf/MXgDDdBUHaCTT793hyBeDbQuciARDJAW24Q1RCmjcwWIV/pgrlFa4lAXsmhoa c8UPc82Ijrs6ivlTweFf16VBc4nSLX5FB3ls7S5noRhm5/Zsd4PGPgIHgCZcPgkAnU1S/A/rSqf3F LpU+CbVBDvlVAnOq9gfNF+QiTlOHdZVIe4gEYAU3CUjbleywQqV02BKxPVM0C5/oVjMVx3bri75n1 TkBYGmqAXy9usCkHIsG5CBHmphv9MHmqMZQVsxvCzfnI5IO1+7MoloeeW/lxuyd0pU88dZsV/riHw 87i2GJUJtVlMl5IGBNFpqoNUoqmvRfEMeXhy/kUX4Xc03I1coZIgmwLmCSXwx9MaCPFzV/dOOrju2 xjO+2sYyB5BNtxRqUEyXglpujFZqJxxau7E0eXoYgoY9gtFGsspzFkVNntamVXEWVVgzJJr/EWW0y +jNd54MfPRqH+eCGuqlnNLktSAVz1MvVRY1dxUltSlDZT7P2bUoMorIPu8p7ZCg9dyX1+9T6Muc5d Hxf/BBP/ir+3e8JTFQBFOiLNdFtB9KZWZmIExheXRvbiA8amxheXRvbkBzYW1iYS5vcmc+iQI4BBM BAgAiBQJOldK9AhsDBgsJCAcDAgYVCAIJCgsEFgIDAQIeAQIXgAAKCRAADmhBGVaCFWgWD/0ZRi4h N9FK2BdQs9RwNnFZUr7JidAWfCrs37XrA/56olQl3ojn0fQtrP4DbTmCuh0SfMijB24psy1GnkPep naQ6VRf7Dxg/Y8muZELSOtsv2CKt3/02J1BBitrkkqmHyni5fLLYYg6fub0T/8Kwo1qGPdu1hx2BQ RERYtQ/S5d/T0cACdlzi6w8rs5f09hU9Tu4qV1JLKmBTgUWKN969HPRkxiojLQziHVyM/weR5Reu6 FZVNuVBGqBD+sfk/c98VJHjsQhYJijcsmgMb1NohAzwrBKcSGKOWJToGEO/1RkIN8tqGnYNp2G+aR 685D0chgTl1WzPRM6mFG1+n2b2RR95DxumKVpwBwdLPoCkI24JkeDJ7lXSe3uFWISstFGt0HL8Eew P8RuGC8s5h7Ct91HMNQTbjgA+Vi1foWUVXpEintAKgoywaIDlJfTZIl6Ew8ETN/7DLy8bXYgq0Xzh aKg3CnOUuGQV5/nl4OAX/3jocT5Cz/OtAiNYj5mLPeL5z2ZszjoCAH6caqsF2oLyAnLqRgDgR+wTQ T6gMhr2IRsl+cp8gPHBwQ4uZMb+X00c/Amm9VfviT+BI7B66cnC7Zv6Gvmtu2rEjWDGWPqUgccB7h dMKnKDthkA227/82tYoFiFMb/NwtgGrn5n2vwJyKN6SEoygGrNt0SI84y6hEVbQlSmVmZiBMYXl0b 24gPGpsYXl0b25AcHJpbWFyeWRhdGEuY29tPokCOQQTAQIAIwUCU4xmKQIbAwcLCQgHAwIBBhUIAg kKCwQWAgMBAh4BAheAAAoJEAAOaEEZVoIV1H0P/j4OUTwFd7BBbpoSp695qb6HqCzWMuExsp8nZjr uymMaeZbGr3OWMNEXRI1FWNHMtcMHWLP/RaDqCJil28proO+PQ/yPhsr2QqJcW4nr91tBrv/MqItu AXLYlsgXqp4BxLP67bzRJ1Bd2x0bWXurpEXY//VBOLnODqThGEcL7jouwjmnRh9FTKZfBDpFRaEfD FOXIfAkMKBa/c9TQwRpx2DPsl3eFWVCNuNGKeGsirLqCxUg5kWTxEorROppz9oU4HPicL6rRH22Ce 6nOAON2vHvhkUuO3GbffhrcsPD4DaYup4ic+DxWm+DaSSRJ+e1yJvwi6NmQ9P9UAuLG93S2MdNNbo sZ9P8k2mTOVKMc+GooI9Ve/vH8unwitwo7ORMVXhJeU6Q0X7zf3SjwDq2lBhn1DSuTsn2DbsNTiDv qrAaCvbsTsw+SZRwF85eG67eAwouYk+dnKmp1q57LDKMyzysij2oDKbcBlwB/TeX16p8+LxECv51a sjS9TInnipssssUDrHIvoTTXWcz7Y5wIngxDFwT8rPY3EggzLGfK5Zx2Q5S/N0FfmADmKknG/D8qG IcJE574D956tiUDKN4I+/g125ORR1v7bP+OIaayAvq17RP+qcAqkxc0x8iCYVCYDouDyNvWPGRhbL UO7mlBpjW9jK9e2fvZY9iw3QzIPGKtClKZWZmIExheXRvbiA8amVmZi5sYXl0b25AcHJpbWFyeWRh dGEuY29tPokCOQQTAQIAIwUCU4xmUAIbAwcLCQgHAwIBBhUIAgkKCwQWAgMBAh4BAheAAAoJEAAOa EEZVoIVzJoQALFCS6n/FHQS+hIzHIb56JbokhK0AFqoLVzLKzrnaeXhE5isWcVg0eoV2oTScIwUSU apy94if69tnUo4Q7YNt8/6yFM6hwZAxFjOXR0ciGE3Q+Z1zi49Ox51yjGMQGxlakV9ep4sV/d5a50 M+LFTmYSAFp6HY23JN9PkjVJC4PUv5DYRbOZ6Y1+TfXKBAewMVqtwT1Y+LPlfmI8dbbbuUX/kKZ5d dhV2736fgyfpslvJKYl0YifUOVy4D1G/oSycyHkJG78OvX4JKcf2kKzVvg7/Rnv+AueCfFQ6nGwPn 0P91I7TEOC4XfZ6a1K3uTp4fPPs1Wn75X7K8lzJP/p8lme40uqwAyBjk+IA5VGd+CVRiyJTpGZwA0 jwSYLyXboX+Dqm9pSYzmC9+/AE7lIgpWj+3iNisp1SWtHc4pdtQ5EU2SEz8yKvDbD0lNDbv4ljI7e flPsvN6vOrxz24mCliEco5DwhpaaSnzWnbAPXhQDWb/lUgs/JNk8dtwmvWnqCwRqElMLVisAbJmC0 BhZ/Ab4sph3EaiZfdXKhiQqSGdK4La3OTJOJYZphPdGgnkvDV9Pl1QZ0ijXQrVIy3zd6VCNaKYq7B AKidn5g/2Q8oio9Tf4XfdZ9dtwcB+bwDJFgvvDYaZ5bI3ln4V3EyW5i2NfXazz/GA/I/ZtbsigCFc 8ftCBKZWZmIExheXRvbiA8amxheXRvbkBrZXJuZWwub3JnPokCOAQTAQIAIgUCWe8u6AIbAwYLCQg HAwIGFQgCCQoLBBYCAwECHgECF4AACgkQAA5oQRlWghUuCg/+Lb/xGxZD2Q1oJVAE37uW308UpVSD 2tAMJUvFTdDbfe3zKlPDTuVsyNsALBGclPLagJ5ZTP+Vp2irAN9uwBuacBOTtmOdz4ZN2tdvNgozz uxp4CHBDVzAslUi2idy+xpsp47DWPxYFIRP3M8QG/aNW052LaPc0cedYxp8+9eiVUNpxF4SiU4i9J DfX/sn9XcfoVZIxMpCRE750zvJvcCUz9HojsrMQ1NFc7MFT1z3MOW2/RlzPcog7xvR5ENPH19ojRD CHqumUHRry+RF0lH00clzX/W8OrQJZtoBPXv9ahka/Vp7kEulcBJr1cH5Wz/WprhsIM7U9pse1f1g Yy9YbXtWctUz8uvDR7shsQxAhX3qO7DilMtuGo1v97I/Kx4gXQ52syh/w6EBny71CZrOgD6kJwPVV AaM1LRC28muq91WCFhs/nzHozpbzcheyGtMUI2Ao4K6mnY+3zIuXPygZMFr9KXE6fF7HzKxKuZMJO aEZCiDOq0anx6FmOzs5E6Jqdpo/mtI8beK+BE7Va6ni7YrQlnT0i3vaTVMTiCThbqsB20VrbMjlhp f8lfK1XVNbRq/R7GZ9zHESlsa35ha60yd/j3pu5hT2xyy8krV8vGhHvnJ1XRMJBAB/UYb6FyC7S+m QZIQXVeAA+smfTT0tDrisj1U5x6ZB9b3nBg65kc= Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.58.1 (3.58.1-1.fc43) Precedence: bulk X-Mailing-List: netfs@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Thu, 2025-11-06 at 11:50 +1100, NeilBrown wrote: > From: NeilBrown >=20 > start_renaming() combines name lookup and locking to prepare for rename. > It is used when two names need to be looked up as in nfsd and overlayfs - > cases where one or both dentries are already available will be handled > separately. >=20 > __start_renaming() avoids the inode_permission check and hash > calculation and is suitable after filename_parentat() in do_renameat2(). > It subsumes quite a bit of code from that function. >=20 > start_renaming() does calculate the hash and check X permission and is > suitable elsewhere: > - nfsd_rename() > - ovl_rename() >=20 > In ovl, ovl_do_rename_rd() is factored out of ovl_do_rename(), which > itself will be gone by the end of the series. >=20 > Acked-by: Chuck Lever (for nfsd parts) > Reviewed-by: Amir Goldstein > Signed-off-by: NeilBrown >=20 > -- > Changes since v3: > - added missig dput() in ovl_rename when "whiteout" is not-NULL. >=20 > Changes since v2: > - in __start_renaming() some label have been renamed, and err > is always set before a "goto out_foo" rather than passing the > error in a dentry*. > - ovl_do_rename() changed to call the new ovl_do_rename_rd() rather > than keeping duplicate code > - code around ovl_cleanup() call in ovl_rename() restructured. > --- > fs/namei.c | 197 ++++++++++++++++++++++++++++----------- > fs/nfsd/vfs.c | 73 +++++---------- > fs/overlayfs/dir.c | 74 +++++++-------- > fs/overlayfs/overlayfs.h | 23 +++-- > include/linux/namei.h | 3 + > 5 files changed, 218 insertions(+), 152 deletions(-) >=20 > diff --git a/fs/namei.c b/fs/namei.c > index e70d056b9543..bad6c9d540f9 100644 > --- a/fs/namei.c > +++ b/fs/namei.c > @@ -3667,6 +3667,129 @@ void unlock_rename(struct dentry *p1, struct dent= ry *p2) > } > EXPORT_SYMBOL(unlock_rename); > =20 > +/** > + * __start_renaming - lookup and lock names for rename > + * @rd: rename data containing parent and flags, and > + * for receiving found dentries > + * @lookup_flags: extra flags to pass to ->lookup (e.g. LOOKUP_REVAL, > + * LOOKUP_NO_SYMLINKS etc). > + * @old_last: name of object in @rd.old_parent > + * @new_last: name of object in @rd.new_parent > + * > + * Look up two names and ensure locks are in place for > + * rename. > + * > + * On success the found dentries are stored in @rd.old_dentry, > + * @rd.new_dentry. These references and the lock are dropped by > + * end_renaming(). > + * > + * The passed in qstrs must have the hash calculated, and no permission > + * checking is performed. > + * > + * Returns: zero or an error. > + */ > +static int > +__start_renaming(struct renamedata *rd, int lookup_flags, > + struct qstr *old_last, struct qstr *new_last) > +{ > + struct dentry *trap; > + struct dentry *d1, *d2; > + int target_flags =3D LOOKUP_RENAME_TARGET | LOOKUP_CREATE; > + int err; > + > + if (rd->flags & RENAME_EXCHANGE) > + target_flags =3D 0; > + if (rd->flags & RENAME_NOREPLACE) > + target_flags |=3D LOOKUP_EXCL; > + > + trap =3D lock_rename(rd->old_parent, rd->new_parent); > + if (IS_ERR(trap)) > + return PTR_ERR(trap); > + > + d1 =3D lookup_one_qstr_excl(old_last, rd->old_parent, > + lookup_flags); > + err =3D PTR_ERR(d1); > + if (IS_ERR(d1)) > + goto out_unlock; > + > + d2 =3D lookup_one_qstr_excl(new_last, rd->new_parent, > + lookup_flags | target_flags); > + err =3D PTR_ERR(d2); > + if (IS_ERR(d2)) > + goto out_dput_d1; > + > + if (d1 =3D=3D trap) { > + /* source is an ancestor of target */ > + err =3D -EINVAL; > + goto out_dput_d2; > + } > + > + if (d2 =3D=3D trap) { > + /* target is an ancestor of source */ > + if (rd->flags & RENAME_EXCHANGE) > + err =3D -EINVAL; > + else > + err =3D -ENOTEMPTY; > + goto out_dput_d2; > + } > + > + rd->old_dentry =3D d1; > + rd->new_dentry =3D d2; > + return 0; > + > +out_dput_d2: > + dput(d2); > +out_dput_d1: > + dput(d1); > +out_unlock: > + unlock_rename(rd->old_parent, rd->new_parent); > + return err; > +} > + > +/** > + * start_renaming - lookup and lock names for rename with permission che= cking > + * @rd: rename data containing parent and flags, and > + * for receiving found dentries > + * @lookup_flags: extra flags to pass to ->lookup (e.g. LOOKUP_REVAL, > + * LOOKUP_NO_SYMLINKS etc). > + * @old_last: name of object in @rd.old_parent > + * @new_last: name of object in @rd.new_parent > + * > + * Look up two names and ensure locks are in place for > + * rename. > + * > + * On success the found dentries are stored in @rd.old_dentry, > + * @rd.new_dentry. These references and the lock are dropped by > + * end_renaming(). > + * > + * The passed in qstrs need not have the hash calculated, and basic > + * eXecute permission checking is performed against @rd.mnt_idmap. > + * > + * Returns: zero or an error. > + */ > +int start_renaming(struct renamedata *rd, int lookup_flags, > + struct qstr *old_last, struct qstr *new_last) > +{ > + int err; > + > + err =3D lookup_one_common(rd->mnt_idmap, old_last, rd->old_parent); > + if (err) > + return err; > + err =3D lookup_one_common(rd->mnt_idmap, new_last, rd->new_parent); > + if (err) > + return err; > + return __start_renaming(rd, lookup_flags, old_last, new_last); > +} > +EXPORT_SYMBOL(start_renaming); > + > +void end_renaming(struct renamedata *rd) > +{ > + unlock_rename(rd->old_parent, rd->new_parent); > + dput(rd->old_dentry); > + dput(rd->new_dentry); > +} > +EXPORT_SYMBOL(end_renaming); > + > /** > * vfs_prepare_mode - prepare the mode to be used for a new inode > * @idmap: idmap of the mount the inode was found from > @@ -5504,14 +5627,11 @@ int do_renameat2(int olddfd, struct filename *fro= m, int newdfd, > struct filename *to, unsigned int flags) > { > struct renamedata rd; > - struct dentry *old_dentry, *new_dentry; > - struct dentry *trap; > struct path old_path, new_path; > struct qstr old_last, new_last; > int old_type, new_type; > struct inode *delegated_inode =3D NULL; > - unsigned int lookup_flags =3D 0, target_flags =3D > - LOOKUP_RENAME_TARGET | LOOKUP_CREATE; > + unsigned int lookup_flags =3D 0; > bool should_retry =3D false; > int error =3D -EINVAL; > =20 > @@ -5522,11 +5642,6 @@ int do_renameat2(int olddfd, struct filename *from= , int newdfd, > (flags & RENAME_EXCHANGE)) > goto put_names; > =20 > - if (flags & RENAME_EXCHANGE) > - target_flags =3D 0; > - if (flags & RENAME_NOREPLACE) > - target_flags |=3D LOOKUP_EXCL; > - > retry: > error =3D filename_parentat(olddfd, from, lookup_flags, &old_path, > &old_last, &old_type); > @@ -5556,66 +5671,40 @@ int do_renameat2(int olddfd, struct filename *fro= m, int newdfd, > goto exit2; > =20 > retry_deleg: > - trap =3D lock_rename(new_path.dentry, old_path.dentry); > - if (IS_ERR(trap)) { > - error =3D PTR_ERR(trap); > + rd.old_parent =3D old_path.dentry; > + rd.mnt_idmap =3D mnt_idmap(old_path.mnt); > + rd.new_parent =3D new_path.dentry; > + rd.delegated_inode =3D &delegated_inode; > + rd.flags =3D flags; > + > + error =3D __start_renaming(&rd, lookup_flags, &old_last, &new_last); > + if (error) > goto exit_lock_rename; > - } > =20 > - old_dentry =3D lookup_one_qstr_excl(&old_last, old_path.dentry, > - lookup_flags); > - error =3D PTR_ERR(old_dentry); > - if (IS_ERR(old_dentry)) > - goto exit3; > - new_dentry =3D lookup_one_qstr_excl(&new_last, new_path.dentry, > - lookup_flags | target_flags); > - error =3D PTR_ERR(new_dentry); > - if (IS_ERR(new_dentry)) > - goto exit4; > if (flags & RENAME_EXCHANGE) { > - if (!d_is_dir(new_dentry)) { > + if (!d_is_dir(rd.new_dentry)) { > error =3D -ENOTDIR; > if (new_last.name[new_last.len]) > - goto exit5; > + goto exit_unlock; > } > } > /* unless the source is a directory trailing slashes give -ENOTDIR */ > - if (!d_is_dir(old_dentry)) { > + if (!d_is_dir(rd.old_dentry)) { > error =3D -ENOTDIR; > if (old_last.name[old_last.len]) > - goto exit5; > + goto exit_unlock; > if (!(flags & RENAME_EXCHANGE) && new_last.name[new_last.len]) > - goto exit5; > - } > - /* source should not be ancestor of target */ > - error =3D -EINVAL; > - if (old_dentry =3D=3D trap) > - goto exit5; > - /* target should not be an ancestor of source */ > - if (!(flags & RENAME_EXCHANGE)) > - error =3D -ENOTEMPTY; > - if (new_dentry =3D=3D trap) > - goto exit5; > + goto exit_unlock; > + } > =20 > - error =3D security_path_rename(&old_path, old_dentry, > - &new_path, new_dentry, flags); > + error =3D security_path_rename(&old_path, rd.old_dentry, > + &new_path, rd.new_dentry, flags); > if (error) > - goto exit5; > + goto exit_unlock; > =20 > - rd.old_parent =3D old_path.dentry; > - rd.old_dentry =3D old_dentry; > - rd.mnt_idmap =3D mnt_idmap(old_path.mnt); > - rd.new_parent =3D new_path.dentry; > - rd.new_dentry =3D new_dentry; > - rd.delegated_inode =3D &delegated_inode; > - rd.flags =3D flags; > error =3D vfs_rename(&rd); > -exit5: > - dput(new_dentry); > -exit4: > - dput(old_dentry); > -exit3: > - unlock_rename(new_path.dentry, old_path.dentry); > +exit_unlock: > + end_renaming(&rd); > exit_lock_rename: > if (delegated_inode) { > error =3D break_deleg_wait(&delegated_inode); > diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c > index 6291c371caa7..a993f1e54182 100644 > --- a/fs/nfsd/vfs.c > +++ b/fs/nfsd/vfs.c > @@ -1885,11 +1885,12 @@ __be32 > nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, in= t flen, > struct svc_fh *tfhp, char *tname, int tlen) > { > - struct dentry *fdentry, *tdentry, *odentry, *ndentry, *trap; > + struct dentry *fdentry, *tdentry; > int type =3D S_IFDIR; > + struct renamedata rd =3D {}; > __be32 err; > int host_err; > - bool close_cached =3D false; > + struct dentry *close_cached; > =20 > trace_nfsd_vfs_rename(rqstp, ffhp, tfhp, fname, flen, tname, tlen); > =20 > @@ -1915,15 +1916,22 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh= *ffhp, char *fname, int flen, > goto out; > =20 > retry: > + close_cached =3D NULL; > host_err =3D fh_want_write(ffhp); > if (host_err) { > err =3D nfserrno(host_err); > goto out; > } > =20 > - trap =3D lock_rename(tdentry, fdentry); > - if (IS_ERR(trap)) { > - err =3D nfserr_xdev; > + rd.mnt_idmap =3D &nop_mnt_idmap; > + rd.old_parent =3D fdentry; > + rd.new_parent =3D tdentry; > + > + host_err =3D start_renaming(&rd, 0, &QSTR_LEN(fname, flen), > + &QSTR_LEN(tname, tlen)); > + > + if (host_err) { > + err =3D nfserrno(host_err); > goto out_want_write; > } > err =3D fh_fill_pre_attrs(ffhp); > @@ -1933,48 +1941,23 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh= *ffhp, char *fname, int flen, > if (err !=3D nfs_ok) > goto out_unlock; > =20 > - odentry =3D lookup_one(&nop_mnt_idmap, &QSTR_LEN(fname, flen), fdentry)= ; > - host_err =3D PTR_ERR(odentry); > - if (IS_ERR(odentry)) > - goto out_nfserr; > + type =3D d_inode(rd.old_dentry)->i_mode & S_IFMT; > + > + if (d_inode(rd.new_dentry)) > + type =3D d_inode(rd.new_dentry)->i_mode & S_IFMT; > =20 > - host_err =3D -ENOENT; > - if (d_really_is_negative(odentry)) > - goto out_dput_old; > - host_err =3D -EINVAL; > - if (odentry =3D=3D trap) > - goto out_dput_old; > - type =3D d_inode(odentry)->i_mode & S_IFMT; > - > - ndentry =3D lookup_one(&nop_mnt_idmap, &QSTR_LEN(tname, tlen), tdentry)= ; > - host_err =3D PTR_ERR(ndentry); > - if (IS_ERR(ndentry)) > - goto out_dput_old; > - if (d_inode(ndentry)) > - type =3D d_inode(ndentry)->i_mode & S_IFMT; > - host_err =3D -ENOTEMPTY; > - if (ndentry =3D=3D trap) > - goto out_dput_new; > - > - if ((ndentry->d_sb->s_export_op->flags & EXPORT_OP_CLOSE_BEFORE_UNLINK)= && > - nfsd_has_cached_files(ndentry)) { > - close_cached =3D true; > - goto out_dput_old; > + if ((rd.new_dentry->d_sb->s_export_op->flags & EXPORT_OP_CLOSE_BEFORE_U= NLINK) && > + nfsd_has_cached_files(rd.new_dentry)) { > + close_cached =3D dget(rd.new_dentry); > + goto out_unlock; > } else { > - struct renamedata rd =3D { > - .mnt_idmap =3D &nop_mnt_idmap, > - .old_parent =3D fdentry, > - .old_dentry =3D odentry, > - .new_parent =3D tdentry, > - .new_dentry =3D ndentry, > - }; > int retries; > =20 > for (retries =3D 1;;) { > host_err =3D vfs_rename(&rd); > if (host_err !=3D -EAGAIN || !retries--) > break; > - if (!nfsd_wait_for_delegreturn(rqstp, d_inode(odentry))) > + if (!nfsd_wait_for_delegreturn(rqstp, d_inode(rd.old_dentry))) > break; > } > if (!host_err) { > @@ -1983,11 +1966,6 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh = *ffhp, char *fname, int flen, > host_err =3D commit_metadata(ffhp); > } > } > - out_dput_new: > - dput(ndentry); > - out_dput_old: > - dput(odentry); > - out_nfserr: > if (host_err =3D=3D -EBUSY) { > /* > * See RFC 8881 Section 18.26.4 para 1-3: NFSv4 RENAME > @@ -2006,7 +1984,7 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *= ffhp, char *fname, int flen, > fh_fill_post_attrs(tfhp); > } > out_unlock: > - unlock_rename(tdentry, fdentry); > + end_renaming(&rd); > out_want_write: > fh_drop_write(ffhp); > =20 > @@ -2017,9 +1995,8 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *= ffhp, char *fname, int flen, > * until this point and then reattempt the whole shebang. > */ > if (close_cached) { > - close_cached =3D false; > - nfsd_close_cached_files(ndentry); > - dput(ndentry); > + nfsd_close_cached_files(close_cached); > + dput(close_cached); > goto retry; > } > out: > diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c > index 6d1d0e94e287..cf6fc48459f3 100644 > --- a/fs/overlayfs/dir.c > +++ b/fs/overlayfs/dir.c > @@ -1124,9 +1124,7 @@ static int ovl_rename(struct mnt_idmap *idmap, stru= ct inode *olddir, > int err; > struct dentry *old_upperdir; > struct dentry *new_upperdir; > - struct dentry *olddentry =3D NULL; > - struct dentry *newdentry =3D NULL; > - struct dentry *trap, *de; > + struct renamedata rd =3D {}; > bool old_opaque; > bool new_opaque; > bool cleanup_whiteout =3D false; > @@ -1136,6 +1134,7 @@ static int ovl_rename(struct mnt_idmap *idmap, stru= ct inode *olddir, > bool new_is_dir =3D d_is_dir(new); > bool samedir =3D olddir =3D=3D newdir; > struct dentry *opaquedir =3D NULL; > + struct dentry *whiteout =3D NULL; > const struct cred *old_cred =3D NULL; > struct ovl_fs *ofs =3D OVL_FS(old->d_sb); > LIST_HEAD(list); > @@ -1233,29 +1232,21 @@ static int ovl_rename(struct mnt_idmap *idmap, st= ruct inode *olddir, > } > } > =20 > - trap =3D lock_rename(new_upperdir, old_upperdir); > - if (IS_ERR(trap)) { > - err =3D PTR_ERR(trap); > - goto out_revert_creds; > - } > + rd.mnt_idmap =3D ovl_upper_mnt_idmap(ofs); > + rd.old_parent =3D old_upperdir; > + rd.new_parent =3D new_upperdir; > + rd.flags =3D flags; > =20 > - de =3D ovl_lookup_upper(ofs, old->d_name.name, old_upperdir, > - old->d_name.len); > - err =3D PTR_ERR(de); > - if (IS_ERR(de)) > - goto out_unlock; > - olddentry =3D de; > + err =3D start_renaming(&rd, 0, > + &QSTR_LEN(old->d_name.name, old->d_name.len), > + &QSTR_LEN(new->d_name.name, new->d_name.len)); > =20 > - err =3D -ESTALE; > - if (!ovl_matches_upper(old, olddentry)) > - goto out_unlock; > + if (err) > + goto out_revert_creds; > =20 > - de =3D ovl_lookup_upper(ofs, new->d_name.name, new_upperdir, > - new->d_name.len); > - err =3D PTR_ERR(de); > - if (IS_ERR(de)) > + err =3D -ESTALE; > + if (!ovl_matches_upper(old, rd.old_dentry)) > goto out_unlock; > - newdentry =3D de; > =20 > old_opaque =3D ovl_dentry_is_opaque(old); > new_opaque =3D ovl_dentry_is_opaque(new); > @@ -1263,15 +1254,15 @@ static int ovl_rename(struct mnt_idmap *idmap, st= ruct inode *olddir, > err =3D -ESTALE; > if (d_inode(new) && ovl_dentry_upper(new)) { > if (opaquedir) { > - if (newdentry !=3D opaquedir) > + if (rd.new_dentry !=3D opaquedir) > goto out_unlock; > } else { > - if (!ovl_matches_upper(new, newdentry)) > + if (!ovl_matches_upper(new, rd.new_dentry)) > goto out_unlock; > } > } else { > - if (!d_is_negative(newdentry)) { > - if (!new_opaque || !ovl_upper_is_whiteout(ofs, newdentry)) > + if (!d_is_negative(rd.new_dentry)) { > + if (!new_opaque || !ovl_upper_is_whiteout(ofs, rd.new_dentry)) > goto out_unlock; > } else { > if (flags & RENAME_EXCHANGE) > @@ -1279,19 +1270,14 @@ static int ovl_rename(struct mnt_idmap *idmap, st= ruct inode *olddir, > } > } > =20 > - if (olddentry =3D=3D trap) > - goto out_unlock; > - if (newdentry =3D=3D trap) > - goto out_unlock; > - > - if (olddentry->d_inode =3D=3D newdentry->d_inode) > + if (rd.old_dentry->d_inode =3D=3D rd.new_dentry->d_inode) > goto out_unlock; > =20 > err =3D 0; > if (ovl_type_merge_or_lower(old)) > err =3D ovl_set_redirect(old, samedir); > else if (is_dir && !old_opaque && ovl_type_merge(new->d_parent)) > - err =3D ovl_set_opaque_xerr(old, olddentry, -EXDEV); > + err =3D ovl_set_opaque_xerr(old, rd.old_dentry, -EXDEV); > if (err) > goto out_unlock; > =20 > @@ -1299,18 +1285,24 @@ static int ovl_rename(struct mnt_idmap *idmap, st= ruct inode *olddir, > err =3D ovl_set_redirect(new, samedir); > else if (!overwrite && new_is_dir && !new_opaque && > ovl_type_merge(old->d_parent)) > - err =3D ovl_set_opaque_xerr(new, newdentry, -EXDEV); > + err =3D ovl_set_opaque_xerr(new, rd.new_dentry, -EXDEV); > if (err) > goto out_unlock; > =20 > - err =3D ovl_do_rename(ofs, old_upperdir, olddentry, > - new_upperdir, newdentry, flags); > - unlock_rename(new_upperdir, old_upperdir); > + err =3D ovl_do_rename_rd(&rd); > + > + if (!err && cleanup_whiteout) > + whiteout =3D dget(rd.new_dentry); > + > + end_renaming(&rd); > + > if (err) > goto out_revert_creds; > =20 > - if (cleanup_whiteout) > - ovl_cleanup(ofs, old_upperdir, newdentry); > + if (whiteout) { > + ovl_cleanup(ofs, old_upperdir, whiteout); > + dput(whiteout); > + } > =20 > if (overwrite && d_inode(new)) { > if (new_is_dir) > @@ -1336,14 +1328,12 @@ static int ovl_rename(struct mnt_idmap *idmap, st= ruct inode *olddir, > else > ovl_drop_write(old); > out: > - dput(newdentry); > - dput(olddentry); > dput(opaquedir); > ovl_cache_free(&list); > return err; > =20 > out_unlock: > - unlock_rename(new_upperdir, old_upperdir); > + end_renaming(&rd); > goto out_revert_creds; > } > =20 > diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h > index 49ad65f829dc..3cc85a893b5c 100644 > --- a/fs/overlayfs/overlayfs.h > +++ b/fs/overlayfs/overlayfs.h > @@ -355,11 +355,24 @@ static inline int ovl_do_remove_acl(struct ovl_fs *= ofs, struct dentry *dentry, > return vfs_remove_acl(ovl_upper_mnt_idmap(ofs), dentry, acl_name); > } > =20 > +static inline int ovl_do_rename_rd(struct renamedata *rd) > +{ > + int err; > + > + pr_debug("rename(%pd2, %pd2, 0x%x)\n", rd->old_dentry, rd->new_dentry, > + rd->flags); > + err =3D vfs_rename(rd); > + if (err) { > + pr_debug("...rename(%pd2, %pd2, ...) =3D %i\n", > + rd->old_dentry, rd->new_dentry, err); > + } > + return err; > +} > + > static inline int ovl_do_rename(struct ovl_fs *ofs, struct dentry *olddi= r, > struct dentry *olddentry, struct dentry *newdir, > struct dentry *newdentry, unsigned int flags) > { > - int err; > struct renamedata rd =3D { > .mnt_idmap =3D ovl_upper_mnt_idmap(ofs), > .old_parent =3D olddir, > @@ -369,13 +382,7 @@ static inline int ovl_do_rename(struct ovl_fs *ofs, = struct dentry *olddir, > .flags =3D flags, > }; > =20 > - pr_debug("rename(%pd2, %pd2, 0x%x)\n", olddentry, newdentry, flags); > - err =3D vfs_rename(&rd); > - if (err) { > - pr_debug("...rename(%pd2, %pd2, ...) =3D %i\n", > - olddentry, newdentry, err); > - } > - return err; > + return ovl_do_rename_rd(&rd); > } > =20 > static inline int ovl_do_whiteout(struct ovl_fs *ofs, > diff --git a/include/linux/namei.h b/include/linux/namei.h > index 196c66156a8a..7fdd9fdcbd2b 100644 > --- a/include/linux/namei.h > +++ b/include/linux/namei.h > @@ -157,6 +157,9 @@ extern int follow_up(struct path *); > extern struct dentry *lock_rename(struct dentry *, struct dentry *); > extern struct dentry *lock_rename_child(struct dentry *, struct dentry *= ); > extern void unlock_rename(struct dentry *, struct dentry *); > +int start_renaming(struct renamedata *rd, int lookup_flags, > + struct qstr *old_last, struct qstr *new_last); > +void end_renaming(struct renamedata *rd); > =20 > /** > * mode_strip_umask - handle vfs umask stripping Reviewed-by: Jeff Layton