linux/fs/nfs/nfs3acl.c
ZhangXiaoxu ded52fbe70 nfs: fix xfstest generic/099 failed on nfsv3
After setxattr, the nfsv3 cached the acl which set by user.

But at the backend, the shared file system (eg. ext4) will check
the acl, if it can merged with mode, it won't add acl to the file.
So, the nfsv3 cached acl is redundant.

Don't 'set_cached_acl' when setxattr.

Signed-off-by: ZhangXiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-02-20 17:33:55 -05:00

337 lines
7.9 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/fs.h>
#include <linux/gfp.h>
#include <linux/nfs.h>
#include <linux/nfs3.h>
#include <linux/nfs_fs.h>
#include <linux/posix_acl_xattr.h>
#include <linux/nfsacl.h>
#include "internal.h"
#include "nfs3_fs.h"
#define NFSDBG_FACILITY NFSDBG_PROC
/*
* nfs3_prepare_get_acl, nfs3_complete_get_acl, nfs3_abort_get_acl: Helpers for
* caching get_acl results in a race-free way. See fs/posix_acl.c:get_acl()
* for explanations.
*/
static void nfs3_prepare_get_acl(struct posix_acl **p)
{
struct posix_acl *sentinel = uncached_acl_sentinel(current);
if (cmpxchg(p, ACL_NOT_CACHED, sentinel) != ACL_NOT_CACHED) {
/* Not the first reader or sentinel already in place. */
}
}
static void nfs3_complete_get_acl(struct posix_acl **p, struct posix_acl *acl)
{
struct posix_acl *sentinel = uncached_acl_sentinel(current);
/* Only cache the ACL if our sentinel is still in place. */
posix_acl_dup(acl);
if (cmpxchg(p, sentinel, acl) != sentinel)
posix_acl_release(acl);
}
static void nfs3_abort_get_acl(struct posix_acl **p)
{
struct posix_acl *sentinel = uncached_acl_sentinel(current);
/* Remove our sentinel upon failure. */
cmpxchg(p, sentinel, ACL_NOT_CACHED);
}
struct posix_acl *nfs3_get_acl(struct inode *inode, int type)
{
struct nfs_server *server = NFS_SERVER(inode);
struct page *pages[NFSACL_MAXPAGES] = { };
struct nfs3_getaclargs args = {
.fh = NFS_FH(inode),
/* The xdr layer may allocate pages here. */
.pages = pages,
};
struct nfs3_getaclres res = {
NULL,
};
struct rpc_message msg = {
.rpc_argp = &args,
.rpc_resp = &res,
};
int status, count;
if (!nfs_server_capable(inode, NFS_CAP_ACLS))
return ERR_PTR(-EOPNOTSUPP);
status = nfs_revalidate_inode(server, inode);
if (status < 0)
return ERR_PTR(status);
/*
* Only get the access acl when explicitly requested: We don't
* need it for access decisions, and only some applications use
* it. Applications which request the access acl first are not
* penalized from this optimization.
*/
if (type == ACL_TYPE_ACCESS)
args.mask |= NFS_ACLCNT|NFS_ACL;
if (S_ISDIR(inode->i_mode))
args.mask |= NFS_DFACLCNT|NFS_DFACL;
if (args.mask == 0)
return NULL;
dprintk("NFS call getacl\n");
msg.rpc_proc = &server->client_acl->cl_procinfo[ACLPROC3_GETACL];
res.fattr = nfs_alloc_fattr();
if (res.fattr == NULL)
return ERR_PTR(-ENOMEM);
if (args.mask & NFS_ACL)
nfs3_prepare_get_acl(&inode->i_acl);
if (args.mask & NFS_DFACL)
nfs3_prepare_get_acl(&inode->i_default_acl);
status = rpc_call_sync(server->client_acl, &msg, 0);
dprintk("NFS reply getacl: %d\n", status);
/* pages may have been allocated at the xdr layer. */
for (count = 0; count < NFSACL_MAXPAGES && args.pages[count]; count++)
__free_page(args.pages[count]);
switch (status) {
case 0:
status = nfs_refresh_inode(inode, res.fattr);
break;
case -EPFNOSUPPORT:
case -EPROTONOSUPPORT:
dprintk("NFS_V3_ACL extension not supported; disabling\n");
server->caps &= ~NFS_CAP_ACLS;
/* fall through */
case -ENOTSUPP:
status = -EOPNOTSUPP;
default:
goto getout;
}
if ((args.mask & res.mask) != args.mask) {
status = -EIO;
goto getout;
}
if (res.acl_access != NULL) {
if ((posix_acl_equiv_mode(res.acl_access, NULL) == 0) ||
res.acl_access->a_count == 0) {
posix_acl_release(res.acl_access);
res.acl_access = NULL;
}
}
if (res.mask & NFS_ACL)
nfs3_complete_get_acl(&inode->i_acl, res.acl_access);
else
forget_cached_acl(inode, ACL_TYPE_ACCESS);
if (res.mask & NFS_DFACL)
nfs3_complete_get_acl(&inode->i_default_acl, res.acl_default);
else
forget_cached_acl(inode, ACL_TYPE_DEFAULT);
nfs_free_fattr(res.fattr);
if (type == ACL_TYPE_ACCESS) {
posix_acl_release(res.acl_default);
return res.acl_access;
} else {
posix_acl_release(res.acl_access);
return res.acl_default;
}
getout:
nfs3_abort_get_acl(&inode->i_acl);
nfs3_abort_get_acl(&inode->i_default_acl);
posix_acl_release(res.acl_access);
posix_acl_release(res.acl_default);
nfs_free_fattr(res.fattr);
return ERR_PTR(status);
}
static int __nfs3_proc_setacls(struct inode *inode, struct posix_acl *acl,
struct posix_acl *dfacl)
{
struct nfs_server *server = NFS_SERVER(inode);
struct nfs_fattr *fattr;
struct page *pages[NFSACL_MAXPAGES];
struct nfs3_setaclargs args = {
.inode = inode,
.mask = NFS_ACL,
.acl_access = acl,
.pages = pages,
};
struct rpc_message msg = {
.rpc_argp = &args,
.rpc_resp = &fattr,
};
int status = 0;
if (acl == NULL && (!S_ISDIR(inode->i_mode) || dfacl == NULL))
goto out;
status = -EOPNOTSUPP;
if (!nfs_server_capable(inode, NFS_CAP_ACLS))
goto out;
/* We are doing this here because XDR marshalling does not
* return any results, it BUGs. */
status = -ENOSPC;
if (acl != NULL && acl->a_count > NFS_ACL_MAX_ENTRIES)
goto out;
if (dfacl != NULL && dfacl->a_count > NFS_ACL_MAX_ENTRIES)
goto out;
if (S_ISDIR(inode->i_mode)) {
args.mask |= NFS_DFACL;
args.acl_default = dfacl;
args.len = nfsacl_size(acl, dfacl);
} else
args.len = nfsacl_size(acl, NULL);
if (args.len > NFS_ACL_INLINE_BUFSIZE) {
unsigned int npages = 1 + ((args.len - 1) >> PAGE_SHIFT);
status = -ENOMEM;
do {
args.pages[args.npages] = alloc_page(GFP_KERNEL);
if (args.pages[args.npages] == NULL)
goto out_freepages;
args.npages++;
} while (args.npages < npages);
}
dprintk("NFS call setacl\n");
status = -ENOMEM;
fattr = nfs_alloc_fattr();
if (fattr == NULL)
goto out_freepages;
msg.rpc_proc = &server->client_acl->cl_procinfo[ACLPROC3_SETACL];
msg.rpc_resp = fattr;
status = rpc_call_sync(server->client_acl, &msg, 0);
nfs_access_zap_cache(inode);
nfs_zap_acl_cache(inode);
dprintk("NFS reply setacl: %d\n", status);
switch (status) {
case 0:
status = nfs_refresh_inode(inode, fattr);
break;
case -EPFNOSUPPORT:
case -EPROTONOSUPPORT:
dprintk("NFS_V3_ACL SETACL RPC not supported"
"(will not retry)\n");
server->caps &= ~NFS_CAP_ACLS;
/* fall through */
case -ENOTSUPP:
status = -EOPNOTSUPP;
}
nfs_free_fattr(fattr);
out_freepages:
while (args.npages != 0) {
args.npages--;
__free_page(args.pages[args.npages]);
}
out:
return status;
}
int nfs3_proc_setacls(struct inode *inode, struct posix_acl *acl,
struct posix_acl *dfacl)
{
int ret;
ret = __nfs3_proc_setacls(inode, acl, dfacl);
return (ret == -EOPNOTSUPP) ? 0 : ret;
}
int nfs3_set_acl(struct inode *inode, struct posix_acl *acl, int type)
{
struct posix_acl *alloc = NULL, *dfacl = NULL;
int status;
if (S_ISDIR(inode->i_mode)) {
switch(type) {
case ACL_TYPE_ACCESS:
alloc = dfacl = get_acl(inode, ACL_TYPE_DEFAULT);
if (IS_ERR(alloc))
goto fail;
break;
case ACL_TYPE_DEFAULT:
dfacl = acl;
alloc = acl = get_acl(inode, ACL_TYPE_ACCESS);
if (IS_ERR(alloc))
goto fail;
break;
}
}
if (acl == NULL) {
alloc = acl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
if (IS_ERR(alloc))
goto fail;
}
status = __nfs3_proc_setacls(inode, acl, dfacl);
posix_acl_release(alloc);
return status;
fail:
return PTR_ERR(alloc);
}
const struct xattr_handler *nfs3_xattr_handlers[] = {
&posix_acl_access_xattr_handler,
&posix_acl_default_xattr_handler,
NULL,
};
static int
nfs3_list_one_acl(struct inode *inode, int type, const char *name, void *data,
size_t size, ssize_t *result)
{
struct posix_acl *acl;
char *p = data + *result;
acl = get_acl(inode, type);
if (IS_ERR_OR_NULL(acl))
return 0;
posix_acl_release(acl);
*result += strlen(name);
*result += 1;
if (!size)
return 0;
if (*result > size)
return -ERANGE;
strcpy(p, name);
return 0;
}
ssize_t
nfs3_listxattr(struct dentry *dentry, char *data, size_t size)
{
struct inode *inode = d_inode(dentry);
ssize_t result = 0;
int error;
error = nfs3_list_one_acl(inode, ACL_TYPE_ACCESS,
XATTR_NAME_POSIX_ACL_ACCESS, data, size, &result);
if (error)
return error;
error = nfs3_list_one_acl(inode, ACL_TYPE_DEFAULT,
XATTR_NAME_POSIX_ACL_DEFAULT, data, size, &result);
if (error)
return error;
return result;
}