From: bfields@fieldses.org (J. Bruce Fields)
To: Andreas Gruenbacher <agruenba@redhat.com>
Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
linux-nfs@vger.kernel.org, linux-api@vger.kernel.org,
linux-cifs@vger.kernel.org,
linux-security-module@vger.kernel.org
Subject: Re: [RFC v7 30/41] nfsd: Add richacl support
Date: Thu, 24 Sep 2015 15:38:19 -0400 [thread overview]
Message-ID: <20150924193819.GG3823@fieldses.org> (raw)
In-Reply-To: <1441448856-13478-31-git-send-email-agruenba@redhat.com>
On Sat, Sep 05, 2015 at 12:27:25PM +0200, Andreas Gruenbacher wrote:
> On file systems with richacls enabled, get and set richacls directly
> instead of converting from / to posix acls.
ACK.--b.
>
> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
> ---
> fs/nfsd/acl.h | 3 +-
> fs/nfsd/nfs4acl.c | 124 ++++++++++++++++++++++++++++++++++++++---------------
> fs/nfsd/nfs4proc.c | 2 +-
> fs/nfsd/nfs4xdr.c | 34 +++++++++++----
> 4 files changed, 117 insertions(+), 46 deletions(-)
>
> diff --git a/fs/nfsd/acl.h b/fs/nfsd/acl.h
> index 1c5deb5..d73c664 100644
> --- a/fs/nfsd/acl.h
> +++ b/fs/nfsd/acl.h
> @@ -53,8 +53,7 @@ __be32 nfsd4_decode_ace_who(struct richace *ace, struct svc_rqst *rqstp,
> __be32 nfsd4_encode_ace_who(struct xdr_stream *xdr, struct svc_rqst *rqstp,
> struct richace *ace);
>
> -int nfsd4_get_acl(struct svc_rqst *rqstp, struct dentry *dentry,
> - struct richacl **acl);
> +struct richacl *nfsd4_get_acl(struct svc_rqst *rqstp, struct dentry *dentry);
> __be32 nfsd4_set_acl(struct svc_rqst *rqstp, struct svc_fh *fhp,
> struct richacl *acl);
>
> diff --git a/fs/nfsd/nfs4acl.c b/fs/nfsd/nfs4acl.c
> index 582f772..a8d596c 100644
> --- a/fs/nfsd/nfs4acl.c
> +++ b/fs/nfsd/nfs4acl.c
> @@ -38,6 +38,8 @@
> #include <linux/nfs_fs.h>
> #include <linux/richacl_compat.h>
> #include <linux/nfs4acl.h>
> +#include <linux/xattr.h>
> +#include <linux/richacl_xattr.h>
> #include "nfsfh.h"
> #include "nfsd.h"
> #include "idmap.h"
> @@ -126,32 +128,28 @@ static short ace2type(struct richace *);
> static void _posix_to_richacl_one(struct posix_acl *, struct richacl_alloc *,
> unsigned int);
>
> -int
> -nfsd4_get_acl(struct svc_rqst *rqstp, struct dentry *dentry,
> - struct richacl **acl)
> +static struct richacl *
> +nfsd4_get_posix_acl(struct svc_rqst *rqstp, struct dentry *dentry)
> {
> struct inode *inode = d_inode(dentry);
> - int error = 0;
> struct posix_acl *pacl = NULL, *dpacl = NULL;
> struct richacl_alloc alloc;
> unsigned int flags = 0;
> int count;
>
> pacl = get_acl(inode, ACL_TYPE_ACCESS);
> - if (!pacl)
> - pacl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
> -
> - if (IS_ERR(pacl))
> - return PTR_ERR(pacl);
> + if (IS_ERR_OR_NULL(pacl))
> + return (void *)pacl;
>
> - /* allocate for worst case: one (deny, allow) pair each: */
> + /* Allocate for worst case: one (deny, allow) pair each. The resulting
> + acl will be released shortly and won't be cached. */
> count = 2 * pacl->a_count;
>
> if (S_ISDIR(inode->i_mode)) {
> flags = FLAG_DIRECTORY;
> dpacl = get_acl(inode, ACL_TYPE_DEFAULT);
> if (IS_ERR(dpacl)) {
> - error = PTR_ERR(dpacl);
> + alloc.acl = (void *)dpacl;
> goto rel_pacl;
> }
>
> @@ -160,7 +158,7 @@ nfsd4_get_acl(struct svc_rqst *rqstp, struct dentry *dentry,
> }
>
> if (!richacl_prepare(&alloc, count)) {
> - error = -ENOMEM;
> + alloc.acl = ERR_PTR(-ENOMEM);
> goto out;
> }
>
> @@ -169,13 +167,37 @@ nfsd4_get_acl(struct svc_rqst *rqstp, struct dentry *dentry,
> if (dpacl)
> _posix_to_richacl_one(dpacl, &alloc, flags | FLAG_DEFAULT_ACL);
>
> - *acl = alloc.acl;
> -
> out:
> posix_acl_release(dpacl);
> rel_pacl:
> posix_acl_release(pacl);
> - return error;
> + return alloc.acl;
> +}
> +
> +struct richacl *
> +nfsd4_get_acl(struct svc_rqst *rqstp, struct dentry *dentry)
> +{
> + struct inode *inode = d_inode(dentry);
> + struct richacl *acl;
> + int error;
> +
> + if (IS_RICHACL(inode))
> + acl = get_richacl(inode);
> + else
> + acl = nfsd4_get_posix_acl(rqstp, dentry);
> + if (IS_ERR(acl))
> + return acl;
> + else if (acl == NULL) {
> + acl = richacl_from_mode(inode->i_mode);
> + if (acl == NULL)
> + acl = ERR_PTR(-ENOMEM);
> + }
> + error = richacl_apply_masks(&acl, inode->i_uid);
> + if (error) {
> + richacl_put(acl);
> + acl = ERR_PTR(error);
> + }
> + return acl;
> }
>
> struct posix_acl_summary {
> @@ -741,56 +763,88 @@ out_estate:
> return ret;
> }
>
> -__be32
> -nfsd4_set_acl(struct svc_rqst *rqstp, struct svc_fh *fhp, struct richacl *acl)
> +static int
> +nfsd4_set_posix_acl(struct svc_rqst *rqstp, struct dentry *dentry,
> + struct richacl *acl)
> {
> - __be32 error;
> int host_error;
> - struct dentry *dentry;
> - struct inode *inode;
> + struct inode *inode = d_inode(dentry);
> struct posix_acl *pacl = NULL, *dpacl = NULL;
> unsigned int flags = 0;
>
> - /* Get inode */
> - error = fh_verify(rqstp, fhp, 0, NFSD_MAY_SATTR);
> - if (error)
> - return error;
> -
> - dentry = fhp->fh_dentry;
> - inode = d_inode(dentry);
> -
> if (!inode->i_op->set_acl || !IS_POSIXACL(inode))
> - return nfserr_attrnotsupp;
> + return -EOPNOTSUPP;
>
> if (S_ISDIR(inode->i_mode))
> flags = FLAG_DIRECTORY;
>
> host_error = nfs4_richacl_to_posix(acl, &pacl, &dpacl, flags);
> if (host_error == -EINVAL)
> - return nfserr_attrnotsupp;
> + return -EOPNOTSUPP;
> if (host_error < 0)
> - goto out_nfserr;
> + return host_error;
>
> host_error = inode->i_op->set_acl(inode, pacl, ACL_TYPE_ACCESS);
> if (host_error < 0)
> goto out_release;
>
> - if (S_ISDIR(inode->i_mode)) {
> + if (S_ISDIR(inode->i_mode))
> host_error = inode->i_op->set_acl(inode, dpacl,
> ACL_TYPE_DEFAULT);
> - }
>
> out_release:
> posix_acl_release(pacl);
> posix_acl_release(dpacl);
> -out_nfserr:
> + return host_error;
> +}
> +
> +static int
> +nfsd4_set_richacl(struct svc_rqst *rqstp, struct dentry *dentry,
> + struct richacl *acl)
> +{
> + int host_error;
> + struct inode *inode = d_inode(dentry);
> + size_t size = richacl_xattr_size(acl);
> + char *buffer;
> +
> + if (!inode->i_op->setxattr || !IS_RICHACL(inode))
> + return -EOPNOTSUPP;
> +
> + richacl_compute_max_masks(acl);
> +
> + buffer = kmalloc(size, GFP_KERNEL);
> + if (!buffer)
> + return -ENOMEM;
> + richacl_to_xattr(&init_user_ns, acl, buffer, size);
> + host_error = inode->i_op->setxattr(dentry, XATTR_NAME_RICHACL,
> + buffer, size, 0);
> + kfree(buffer);
> + return host_error;
> +}
> +
> +__be32
> +nfsd4_set_acl(struct svc_rqst *rqstp, struct svc_fh *fhp, struct richacl *acl)
> +{
> + struct dentry *dentry;
> + int host_error;
> + __be32 error;
> +
> + error = fh_verify(rqstp, fhp, 0, NFSD_MAY_SATTR);
> + if (error)
> + return error;
> + dentry = fhp->fh_dentry;
> +
> + if (IS_RICHACL(d_inode(dentry)))
> + host_error = nfsd4_set_richacl(rqstp, dentry, acl);
> + else
> + host_error = nfsd4_set_posix_acl(rqstp, dentry, acl);
> +
> if (host_error == -EOPNOTSUPP)
> return nfserr_attrnotsupp;
> else
> return nfserrno(host_error);
> }
>
> -
> static short
> ace2type(struct richace *ace)
> {
> diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
> index 8c2cb16..9f8f0a8 100644
> --- a/fs/nfsd/nfs4proc.c
> +++ b/fs/nfsd/nfs4proc.c
> @@ -110,7 +110,7 @@ check_attr_support(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
> * in current environment or not.
> */
> if (bmval[0] & FATTR4_WORD0_ACL) {
> - if (!IS_POSIXACL(d_inode(dentry)))
> + if (!IS_ACL(d_inode(dentry)))
> return nfserr_attrnotsupp;
> }
>
> diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
> index 465f82a..3280c30 100644
> --- a/fs/nfsd/nfs4xdr.c
> +++ b/fs/nfsd/nfs4xdr.c
> @@ -340,11 +340,24 @@ nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval,
>
> richacl_for_each_entry(ace, *acl) {
> READ_BUF(16); len += 16;
> - ace->e_type = be32_to_cpup(p++);
> - ace->e_flags = be32_to_cpup(p++);
> - ace->e_mask = be32_to_cpup(p++);
> - if (ace->e_flags & RICHACE_SPECIAL_WHO)
> +
> + dummy32 = be32_to_cpup(p++);
> + if (dummy32 > RICHACE_ACCESS_DENIED_ACE_TYPE)
> + return nfserr_inval;
> + ace->e_type = dummy32;
> +
> + dummy32 = be32_to_cpup(p++);
> + if (dummy32 & (~RICHACE_VALID_FLAGS |
> + RICHACE_INHERITED_ACE |
> + RICHACE_SPECIAL_WHO))
> return nfserr_inval;
> + ace->e_flags = dummy32;
> +
> + dummy32 = be32_to_cpup(p++);
> + if (dummy32 & ~NFS4_ACE_MASK_ALL)
> + return nfserr_inval;
> + ace->e_mask = dummy32;
> +
> dummy32 = be32_to_cpup(p++);
> READ_BUF(dummy32);
> len += XDR_QUADLEN(dummy32) << 2;
> @@ -2276,7 +2289,11 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
> fhp = tempfh;
> }
> if (bmval0 & FATTR4_WORD0_ACL) {
> - err = nfsd4_get_acl(rqstp, dentry, &acl);
> + acl = nfsd4_get_acl(rqstp, dentry);
> + if (IS_ERR(acl)) {
> + err = PTR_ERR(acl);
> + acl = NULL;
> + }
> if (err == -EOPNOTSUPP)
> bmval0 &= ~FATTR4_WORD0_ACL;
> else if (err == -EINVAL) {
> @@ -2335,7 +2352,7 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
> u32 word1 = nfsd_suppattrs1(minorversion);
> u32 word2 = nfsd_suppattrs2(minorversion);
>
> - if (!IS_POSIXACL(dentry->d_inode))
> + if (!IS_ACL(d_inode(dentry)))
> word0 &= ~FATTR4_WORD0_ACL;
> if (!contextsupport)
> word2 &= ~FATTR4_WORD2_SECURITY_LABEL;
> @@ -2470,7 +2487,8 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
> if (!p)
> goto out_resource;
> *p++ = cpu_to_be32(ace->e_type);
> - *p++ = cpu_to_be32(ace->e_flags & ~RICHACE_SPECIAL_WHO);
> + *p++ = cpu_to_be32(ace->e_flags &
> + ~(RICHACE_SPECIAL_WHO | RICHACE_INHERITED_ACE));
> *p++ = cpu_to_be32(ace->e_mask & NFS4_ACE_MASK_ALL);
> status = nfsd4_encode_ace_who(xdr, rqstp, ace);
> if (status)
> @@ -2482,7 +2500,7 @@ out_acl:
> p = xdr_reserve_space(xdr, 4);
> if (!p)
> goto out_resource;
> - *p++ = cpu_to_be32(IS_POSIXACL(dentry->d_inode) ?
> + *p++ = cpu_to_be32(IS_ACL(d_inode(dentry)) ?
> ACL4_SUPPORT_ALLOW_ACL|ACL4_SUPPORT_DENY_ACL : 0);
> }
> if (bmval0 & FATTR4_WORD0_CANSETTIME) {
> --
> 2.4.3
>
> --
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next prev parent reply other threads:[~2015-09-24 19:38 UTC|newest]
Thread overview: 109+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-09-05 10:26 [RFC v7 00/41] Richacls Andreas Gruenbacher
2015-09-05 10:26 ` [RFC v7 01/41] vfs: Add IS_ACL() and IS_RICHACL() tests Andreas Gruenbacher
2015-09-05 10:26 ` [RFC v7 02/41] vfs: Add MAY_CREATE_FILE and MAY_CREATE_DIR permission flags Andreas Gruenbacher
2015-09-05 10:26 ` [RFC v7 03/41] vfs: Add MAY_DELETE_SELF and MAY_DELETE_CHILD " Andreas Gruenbacher
2015-09-06 8:14 ` [PATCH] " Andreas Gruenbacher
2015-09-11 20:30 ` J. Bruce Fields
2015-09-05 10:26 ` [RFC v7 04/41] vfs: Make the inode passed to inode_change_ok non-const Andreas Gruenbacher
2015-09-05 10:27 ` [RFC v7 05/41] vfs: Add permission flags for setting file attributes Andreas Gruenbacher
2015-09-05 10:27 ` [RFC v7 06/41] richacl: In-memory representation and helper functions Andreas Gruenbacher
2015-09-05 10:27 ` [RFC v7 07/41] richacl: Permission mapping functions Andreas Gruenbacher
2015-09-05 10:27 ` [RFC v7 08/41] richacl: Compute maximum file masks from an acl Andreas Gruenbacher
2015-09-05 10:27 ` [RFC v7 09/41] richacl: Update the file masks in chmod() Andreas Gruenbacher
2015-09-11 20:35 ` J. Bruce Fields
2015-09-05 10:27 ` [RFC v7 10/41] richacl: Permission check algorithm Andreas Gruenbacher
2015-09-11 21:16 ` J. Bruce Fields
2015-09-11 22:12 ` Andreas Grünbacher
2015-09-17 17:30 ` J. Bruce Fields
2015-09-05 10:27 ` [RFC v7 11/41] vfs: Cache base_acl objects in inodes Andreas Gruenbacher
2015-09-05 10:27 ` [RFC v7 12/41] vfs: Cache richacl in struct inode Andreas Gruenbacher
2015-09-05 10:27 ` [RFC v7 13/41] richacl: Check if an acl is equivalent to a file mode Andreas Gruenbacher
2015-09-17 18:22 ` J. Bruce Fields
2015-09-18 0:56 ` J. Bruce Fields
2015-09-21 13:59 ` Austin S Hemmelgarn
2015-09-21 14:38 ` J. Bruce Fields
2015-09-21 17:00 ` Austin S Hemmelgarn
2015-09-21 17:48 ` J. Bruce Fields
2015-09-21 15:31 ` J. Bruce Fields
2015-09-21 23:26 ` Andreas Gruenbacher
2015-09-21 23:20 ` Andreas Gruenbacher
2015-09-17 18:37 ` J. Bruce Fields
2015-09-05 10:27 ` [RFC v7 14/41] richacl: Create-time inheritance Andreas Gruenbacher
2015-09-18 17:58 ` J. Bruce Fields
2015-09-21 20:37 ` Andreas Gruenbacher
2015-09-05 10:27 ` [RFC v7 15/41] richacl: Automatic Inheritance Andreas Gruenbacher
2015-09-18 18:40 ` J. Bruce Fields
2015-09-21 21:19 ` Andreas Gruenbacher
2015-09-22 1:51 ` J. Bruce Fields
2015-09-23 13:55 ` J. Bruce Fields
2015-09-05 10:27 ` [RFC v7 16/41] richacl: xattr mapping functions Andreas Gruenbacher
2015-09-05 10:27 ` [RFC v7 17/41] vfs: Add richacl permission checking Andreas Gruenbacher
2015-09-05 10:27 ` [RFC v7 18/41] ext4: Add richacl support Andreas Gruenbacher
2015-09-23 2:30 ` Aneesh Kumar K.V
2015-09-05 10:27 ` [RFC v7 19/41] ext4: Add richacl feature flag Andreas Gruenbacher
2015-09-23 2:31 ` Aneesh Kumar K.V
2015-09-05 10:27 ` [RFC v7 20/41] richacl: acl editing helper functions Andreas Gruenbacher
2015-09-18 18:54 ` J. Bruce Fields
2015-09-05 10:27 ` [RFC v7 21/41] richacl: Move everyone@ aces down the acl Andreas Gruenbacher
2015-09-18 19:35 ` J. Bruce Fields
2015-09-21 21:43 ` Andreas Gruenbacher
2015-09-22 1:52 ` J. Bruce Fields
2015-09-05 10:27 ` [RFC v7 22/41] richacl: Propagate everyone@ permissions to other aces Andreas Gruenbacher
2015-09-18 21:36 ` J. Bruce Fields
2015-09-21 23:44 ` Andreas Gruenbacher
2015-09-18 21:56 ` J. Bruce Fields
2015-09-21 19:24 ` J. Bruce Fields
2015-09-23 1:24 ` Andreas Gruenbacher
2015-09-23 1:39 ` Andreas Gruenbacher
2015-09-23 1:46 ` J. Bruce Fields
2015-09-05 10:27 ` [RFC v7 23/41] richacl: Set the owner permissions to the owner mask Andreas Gruenbacher
2015-09-21 21:00 ` J. Bruce Fields
2015-09-05 10:27 ` [RFC v7 24/41] richacl: Set the other permissions to the other mask Andreas Gruenbacher
2015-09-23 14:03 ` J. Bruce Fields
2015-09-23 14:12 ` Andreas Grünbacher
2015-09-05 10:27 ` [RFC v7 25/41] richacl: Isolate the owner and group classes Andreas Gruenbacher
2015-09-22 16:06 ` J. Bruce Fields
2015-09-23 13:11 ` Andreas Gruenbacher
2015-09-23 13:15 ` J. Bruce Fields
2015-09-22 19:02 ` J. Bruce Fields
2015-09-23 13:33 ` Andreas Gruenbacher
2015-09-25 11:25 ` Andreas Gruenbacher
2015-09-25 20:17 ` J. Bruce Fields
2015-09-22 19:02 ` J. Bruce Fields
2015-09-05 10:27 ` [RFC v7 26/41] richacl: Apply the file masks to a richacl Andreas Gruenbacher
2015-09-22 19:11 ` J. Bruce Fields
2015-09-23 19:18 ` J. Bruce Fields
2015-09-23 20:29 ` Andreas Gruenbacher
2015-09-23 20:33 ` J. Bruce Fields
2015-09-23 20:40 ` Andreas Gruenbacher
2015-09-23 21:05 ` J. Bruce Fields
2015-09-23 22:14 ` Andreas Gruenbacher
2015-09-24 15:28 ` J. Bruce Fields
2015-09-24 15:48 ` Andreas Gruenbacher
2015-09-22 20:50 ` J. Bruce Fields
2015-09-24 18:33 ` J. Bruce Fields
2015-09-25 16:21 ` [PATCH] richacl: Possible other write-through fix Andreas Gruenbacher
2015-09-25 16:45 ` Andreas Gruenbacher
2015-09-25 18:36 ` J. Bruce Fields
2015-09-05 10:27 ` [RFC v7 27/41] richacl: Create richacl from mode values Andreas Gruenbacher
2015-09-23 20:11 ` J. Bruce Fields
2015-09-05 10:27 ` [RFC v7 28/41] nfsd: Keep list of acls to dispose of in compoundargs Andreas Gruenbacher
2015-09-23 20:28 ` J. Bruce Fields
2015-09-05 10:27 ` [RFC v7 29/41] nfsd: Use richacls as internal acl representation Andreas Gruenbacher
2015-09-24 19:29 ` J. Bruce Fields
2015-09-05 10:27 ` [RFC v7 30/41] nfsd: Add richacl support Andreas Gruenbacher
2015-09-24 19:38 ` J. Bruce Fields [this message]
2015-09-05 10:27 ` [RFC v7 31/41] nfsd: Add support for the v4.1 dacl attribute Andreas Gruenbacher
2015-09-24 19:59 ` J. Bruce Fields
2015-09-25 16:37 ` Andreas Gruenbacher
2015-09-05 10:27 ` [RFC v7 32/41] nfsd: Add support for the MAY_CREATE_{FILE,DIR} permissions Andreas Gruenbacher
2015-09-24 20:01 ` J. Bruce Fields
2015-09-05 10:27 ` [RFC v7 33/41] richacl: Add support for unmapped identifiers Andreas Gruenbacher
2015-09-05 10:27 ` [RFC v7 34/41] ext4: Don't allow unmapped identifiers in richacls Andreas Gruenbacher
2015-09-05 10:27 ` [RFC v7 35/41] sunrpc: Allow to demand-allocate pages to encode into Andreas Gruenbacher
2015-09-05 10:27 ` [RFC v7 36/41] sunrpc: Add xdr_init_encode_pages Andreas Gruenbacher
2015-09-05 10:27 ` [RFC v7 37/41] nfs: Fix GETATTR bitmap verification Andreas Gruenbacher
2015-09-05 10:27 ` [RFC v7 38/41] nfs: Remove unused xdr page offsets in getacl/setacl arguments Andreas Gruenbacher
2015-09-05 10:27 ` [RFC v7 39/41] nfs: Add richacl support Andreas Gruenbacher
2015-09-05 10:27 ` [RFC v7 40/41] nfs: Add support for the v4.1 dacl attribute Andreas Gruenbacher
2015-09-05 10:27 ` [RFC v7 41/41] richacl: uapi header split Andreas Gruenbacher
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