linux/fs/nfs/super.c
Eric W. Biederman 95dd77580c fs: Teach path_connected to handle nfs filesystems with multiple roots.
On nfsv2 and nfsv3 the nfs server can export subsets of the same
filesystem and report the same filesystem identifier, so that the nfs
client can know they are the same filesystem.  The subsets can be from
disjoint directory trees.  The nfsv2 and nfsv3 filesystems provides no
way to find the common root of all directory trees exported form the
server with the same filesystem identifier.

The practical result is that in struct super s_root for nfs s_root is
not necessarily the root of the filesystem.  The nfs mount code sets
s_root to the root of the first subset of the nfs filesystem that the
kernel mounts.

This effects the dcache invalidation code in generic_shutdown_super
currently called shrunk_dcache_for_umount and that code for years
has gone through an additional list of dentries that might be dentry
trees that need to be freed to accomodate nfs.

When I wrote path_connected I did not realize nfs was so special, and
it's hueristic for avoiding calling is_subdir can fail.

The practical case where this fails is when there is a move of a
directory from the subtree exposed by one nfs mount to the subtree
exposed by another nfs mount.  This move can happen either locally or
remotely.  With the remote case requiring that the move directory be cached
before the move and that after the move someone walks the path
to where the move directory now exists and in so doing causes the
already cached directory to be moved in the dcache through the magic
of d_splice_alias.

If someone whose working directory is in the move directory or a
subdirectory and now starts calling .. from the initial mount of nfs
(where s_root == mnt_root), then path_connected as a heuristic will
not bother with the is_subdir check.  As s_root really is not the root
of the nfs filesystem this heuristic is wrong, and the path may
actually not be connected and path_connected can fail.

The is_subdir function might be cheap enough that we can call it
unconditionally.  Verifying that will take some benchmarking and
the result may not be the same on all kernels this fix needs
to be backported to.  So I am avoiding that for now.

Filesystems with snapshots such as nilfs and btrfs do something
similar.  But as the directory tree of the snapshots are disjoint
from one another and from the main directory tree rename won't move
things between them and this problem will not occur.

Cc: stable@vger.kernel.org
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Fixes: 397d425dc2 ("vfs: Test for and handle paths that are unreachable from their mnt_root")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-03-15 18:48:38 -04:00

2941 lines
76 KiB
C

/*
* linux/fs/nfs/super.c
*
* Copyright (C) 1992 Rick Sladkey
*
* nfs superblock handling functions
*
* Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
* experimental NFS changes. Modularisation taken straight from SYS5 fs.
*
* Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
* J.S.Peatfield@damtp.cam.ac.uk
*
* Split from inode.c by David Howells <dhowells@redhat.com>
*
* - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
* particular server are held in the same superblock
* - NFS superblocks can have several effective roots to the dentry tree
* - directory type roots are spliced into the tree when a path from one root reaches the root
* of another (see nfs_lookup())
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/time.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/stat.h>
#include <linux/errno.h>
#include <linux/unistd.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/addr.h>
#include <linux/sunrpc/stats.h>
#include <linux/sunrpc/metrics.h>
#include <linux/sunrpc/xprtsock.h>
#include <linux/sunrpc/xprtrdma.h>
#include <linux/nfs_fs.h>
#include <linux/nfs_mount.h>
#include <linux/nfs4_mount.h>
#include <linux/lockd/bind.h>
#include <linux/seq_file.h>
#include <linux/mount.h>
#include <linux/namei.h>
#include <linux/vfs.h>
#include <linux/inet.h>
#include <linux/in6.h>
#include <linux/slab.h>
#include <net/ipv6.h>
#include <linux/netdevice.h>
#include <linux/nfs_xdr.h>
#include <linux/magic.h>
#include <linux/parser.h>
#include <linux/nsproxy.h>
#include <linux/rcupdate.h>
#include <linux/uaccess.h>
#include "nfs4_fs.h"
#include "callback.h"
#include "delegation.h"
#include "iostat.h"
#include "internal.h"
#include "fscache.h"
#include "nfs4session.h"
#include "pnfs.h"
#include "nfs.h"
#define NFSDBG_FACILITY NFSDBG_VFS
#define NFS_TEXT_DATA 1
#if IS_ENABLED(CONFIG_NFS_V3)
#define NFS_DEFAULT_VERSION 3
#else
#define NFS_DEFAULT_VERSION 2
#endif
enum {
/* Mount options that take no arguments */
Opt_soft, Opt_hard,
Opt_posix, Opt_noposix,
Opt_cto, Opt_nocto,
Opt_ac, Opt_noac,
Opt_lock, Opt_nolock,
Opt_udp, Opt_tcp, Opt_rdma,
Opt_acl, Opt_noacl,
Opt_rdirplus, Opt_nordirplus,
Opt_sharecache, Opt_nosharecache,
Opt_resvport, Opt_noresvport,
Opt_fscache, Opt_nofscache,
Opt_migration, Opt_nomigration,
/* Mount options that take integer arguments */
Opt_port,
Opt_rsize, Opt_wsize, Opt_bsize,
Opt_timeo, Opt_retrans,
Opt_acregmin, Opt_acregmax,
Opt_acdirmin, Opt_acdirmax,
Opt_actimeo,
Opt_namelen,
Opt_mountport,
Opt_mountvers,
Opt_minorversion,
/* Mount options that take string arguments */
Opt_nfsvers,
Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
Opt_addr, Opt_mountaddr, Opt_clientaddr,
Opt_lookupcache,
Opt_fscache_uniq,
Opt_local_lock,
/* Special mount options */
Opt_userspace, Opt_deprecated, Opt_sloppy,
Opt_err
};
static const match_table_t nfs_mount_option_tokens = {
{ Opt_userspace, "bg" },
{ Opt_userspace, "fg" },
{ Opt_userspace, "retry=%s" },
{ Opt_sloppy, "sloppy" },
{ Opt_soft, "soft" },
{ Opt_hard, "hard" },
{ Opt_deprecated, "intr" },
{ Opt_deprecated, "nointr" },
{ Opt_posix, "posix" },
{ Opt_noposix, "noposix" },
{ Opt_cto, "cto" },
{ Opt_nocto, "nocto" },
{ Opt_ac, "ac" },
{ Opt_noac, "noac" },
{ Opt_lock, "lock" },
{ Opt_nolock, "nolock" },
{ Opt_udp, "udp" },
{ Opt_tcp, "tcp" },
{ Opt_rdma, "rdma" },
{ Opt_acl, "acl" },
{ Opt_noacl, "noacl" },
{ Opt_rdirplus, "rdirplus" },
{ Opt_nordirplus, "nordirplus" },
{ Opt_sharecache, "sharecache" },
{ Opt_nosharecache, "nosharecache" },
{ Opt_resvport, "resvport" },
{ Opt_noresvport, "noresvport" },
{ Opt_fscache, "fsc" },
{ Opt_nofscache, "nofsc" },
{ Opt_migration, "migration" },
{ Opt_nomigration, "nomigration" },
{ Opt_port, "port=%s" },
{ Opt_rsize, "rsize=%s" },
{ Opt_wsize, "wsize=%s" },
{ Opt_bsize, "bsize=%s" },
{ Opt_timeo, "timeo=%s" },
{ Opt_retrans, "retrans=%s" },
{ Opt_acregmin, "acregmin=%s" },
{ Opt_acregmax, "acregmax=%s" },
{ Opt_acdirmin, "acdirmin=%s" },
{ Opt_acdirmax, "acdirmax=%s" },
{ Opt_actimeo, "actimeo=%s" },
{ Opt_namelen, "namlen=%s" },
{ Opt_mountport, "mountport=%s" },
{ Opt_mountvers, "mountvers=%s" },
{ Opt_minorversion, "minorversion=%s" },
{ Opt_nfsvers, "nfsvers=%s" },
{ Opt_nfsvers, "vers=%s" },
{ Opt_sec, "sec=%s" },
{ Opt_proto, "proto=%s" },
{ Opt_mountproto, "mountproto=%s" },
{ Opt_addr, "addr=%s" },
{ Opt_clientaddr, "clientaddr=%s" },
{ Opt_mounthost, "mounthost=%s" },
{ Opt_mountaddr, "mountaddr=%s" },
{ Opt_lookupcache, "lookupcache=%s" },
{ Opt_fscache_uniq, "fsc=%s" },
{ Opt_local_lock, "local_lock=%s" },
/* The following needs to be listed after all other options */
{ Opt_nfsvers, "v%s" },
{ Opt_err, NULL }
};
enum {
Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
Opt_xprt_rdma6,
Opt_xprt_err
};
static const match_table_t nfs_xprt_protocol_tokens = {
{ Opt_xprt_udp, "udp" },
{ Opt_xprt_udp6, "udp6" },
{ Opt_xprt_tcp, "tcp" },
{ Opt_xprt_tcp6, "tcp6" },
{ Opt_xprt_rdma, "rdma" },
{ Opt_xprt_rdma6, "rdma6" },
{ Opt_xprt_err, NULL }
};
enum {
Opt_sec_none, Opt_sec_sys,
Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
Opt_sec_err
};
static const match_table_t nfs_secflavor_tokens = {
{ Opt_sec_none, "none" },
{ Opt_sec_none, "null" },
{ Opt_sec_sys, "sys" },
{ Opt_sec_krb5, "krb5" },
{ Opt_sec_krb5i, "krb5i" },
{ Opt_sec_krb5p, "krb5p" },
{ Opt_sec_lkey, "lkey" },
{ Opt_sec_lkeyi, "lkeyi" },
{ Opt_sec_lkeyp, "lkeyp" },
{ Opt_sec_spkm, "spkm3" },
{ Opt_sec_spkmi, "spkm3i" },
{ Opt_sec_spkmp, "spkm3p" },
{ Opt_sec_err, NULL }
};
enum {
Opt_lookupcache_all, Opt_lookupcache_positive,
Opt_lookupcache_none,
Opt_lookupcache_err
};
static match_table_t nfs_lookupcache_tokens = {
{ Opt_lookupcache_all, "all" },
{ Opt_lookupcache_positive, "pos" },
{ Opt_lookupcache_positive, "positive" },
{ Opt_lookupcache_none, "none" },
{ Opt_lookupcache_err, NULL }
};
enum {
Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
Opt_local_lock_none,
Opt_local_lock_err
};
static match_table_t nfs_local_lock_tokens = {
{ Opt_local_lock_all, "all" },
{ Opt_local_lock_flock, "flock" },
{ Opt_local_lock_posix, "posix" },
{ Opt_local_lock_none, "none" },
{ Opt_local_lock_err, NULL }
};
enum {
Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
Opt_vers_4_1, Opt_vers_4_2,
Opt_vers_err
};
static match_table_t nfs_vers_tokens = {
{ Opt_vers_2, "2" },
{ Opt_vers_3, "3" },
{ Opt_vers_4, "4" },
{ Opt_vers_4_0, "4.0" },
{ Opt_vers_4_1, "4.1" },
{ Opt_vers_4_2, "4.2" },
{ Opt_vers_err, NULL }
};
static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
int flags, const char *dev_name, void *raw_data);
struct file_system_type nfs_fs_type = {
.owner = THIS_MODULE,
.name = "nfs",
.mount = nfs_fs_mount,
.kill_sb = nfs_kill_super,
.fs_flags = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
};
MODULE_ALIAS_FS("nfs");
EXPORT_SYMBOL_GPL(nfs_fs_type);
struct file_system_type nfs_xdev_fs_type = {
.owner = THIS_MODULE,
.name = "nfs",
.mount = nfs_xdev_mount,
.kill_sb = nfs_kill_super,
.fs_flags = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
};
const struct super_operations nfs_sops = {
.alloc_inode = nfs_alloc_inode,
.destroy_inode = nfs_destroy_inode,
.write_inode = nfs_write_inode,
.drop_inode = nfs_drop_inode,
.statfs = nfs_statfs,
.evict_inode = nfs_evict_inode,
.umount_begin = nfs_umount_begin,
.show_options = nfs_show_options,
.show_devname = nfs_show_devname,
.show_path = nfs_show_path,
.show_stats = nfs_show_stats,
.remount_fs = nfs_remount,
};
EXPORT_SYMBOL_GPL(nfs_sops);
#if IS_ENABLED(CONFIG_NFS_V4)
static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
static int nfs4_validate_mount_data(void *options,
struct nfs_parsed_mount_data *args, const char *dev_name);
struct file_system_type nfs4_fs_type = {
.owner = THIS_MODULE,
.name = "nfs4",
.mount = nfs_fs_mount,
.kill_sb = nfs_kill_super,
.fs_flags = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
};
MODULE_ALIAS_FS("nfs4");
MODULE_ALIAS("nfs4");
EXPORT_SYMBOL_GPL(nfs4_fs_type);
static int __init register_nfs4_fs(void)
{
return register_filesystem(&nfs4_fs_type);
}
static void unregister_nfs4_fs(void)
{
unregister_filesystem(&nfs4_fs_type);
}
#else
static int __init register_nfs4_fs(void)
{
return 0;
}
static void unregister_nfs4_fs(void)
{
}
#endif
static struct shrinker acl_shrinker = {
.count_objects = nfs_access_cache_count,
.scan_objects = nfs_access_cache_scan,
.seeks = DEFAULT_SEEKS,
};
/*
* Register the NFS filesystems
*/
int __init register_nfs_fs(void)
{
int ret;
ret = register_filesystem(&nfs_fs_type);
if (ret < 0)
goto error_0;
ret = register_nfs4_fs();
if (ret < 0)
goto error_1;
ret = nfs_register_sysctl();
if (ret < 0)
goto error_2;
ret = register_shrinker(&acl_shrinker);
if (ret < 0)
goto error_3;
return 0;
error_3:
nfs_unregister_sysctl();
error_2:
unregister_nfs4_fs();
error_1:
unregister_filesystem(&nfs_fs_type);
error_0:
return ret;
}
/*
* Unregister the NFS filesystems
*/
void __exit unregister_nfs_fs(void)
{
unregister_shrinker(&acl_shrinker);
nfs_unregister_sysctl();
unregister_nfs4_fs();
unregister_filesystem(&nfs_fs_type);
}
bool nfs_sb_active(struct super_block *sb)
{
struct nfs_server *server = NFS_SB(sb);
if (!atomic_inc_not_zero(&sb->s_active))
return false;
if (atomic_inc_return(&server->active) != 1)
atomic_dec(&sb->s_active);
return true;
}
EXPORT_SYMBOL_GPL(nfs_sb_active);
void nfs_sb_deactive(struct super_block *sb)
{
struct nfs_server *server = NFS_SB(sb);
if (atomic_dec_and_test(&server->active))
deactivate_super(sb);
}
EXPORT_SYMBOL_GPL(nfs_sb_deactive);
/*
* Deliver file system statistics to userspace
*/
int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
{
struct nfs_server *server = NFS_SB(dentry->d_sb);
unsigned char blockbits;
unsigned long blockres;
struct nfs_fh *fh = NFS_FH(d_inode(dentry));
struct nfs_fsstat res;
int error = -ENOMEM;
res.fattr = nfs_alloc_fattr();
if (res.fattr == NULL)
goto out_err;
error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
if (unlikely(error == -ESTALE)) {
struct dentry *pd_dentry;
pd_dentry = dget_parent(dentry);
if (pd_dentry != NULL) {
nfs_zap_caches(d_inode(pd_dentry));
dput(pd_dentry);
}
}
nfs_free_fattr(res.fattr);
if (error < 0)
goto out_err;
buf->f_type = NFS_SUPER_MAGIC;
/*
* Current versions of glibc do not correctly handle the
* case where f_frsize != f_bsize. Eventually we want to
* report the value of wtmult in this field.
*/
buf->f_frsize = dentry->d_sb->s_blocksize;
/*
* On most *nix systems, f_blocks, f_bfree, and f_bavail
* are reported in units of f_frsize. Linux hasn't had
* an f_frsize field in its statfs struct until recently,
* thus historically Linux's sys_statfs reports these
* fields in units of f_bsize.
*/
buf->f_bsize = dentry->d_sb->s_blocksize;
blockbits = dentry->d_sb->s_blocksize_bits;
blockres = (1 << blockbits) - 1;
buf->f_blocks = (res.tbytes + blockres) >> blockbits;
buf->f_bfree = (res.fbytes + blockres) >> blockbits;
buf->f_bavail = (res.abytes + blockres) >> blockbits;
buf->f_files = res.tfiles;
buf->f_ffree = res.afiles;
buf->f_namelen = server->namelen;
return 0;
out_err:
dprintk("%s: statfs error = %d\n", __func__, -error);
return error;
}
EXPORT_SYMBOL_GPL(nfs_statfs);
/*
* Map the security flavour number to a name
*/
static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
{
static const struct {
rpc_authflavor_t flavour;
const char *str;
} sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = {
/* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */
{ RPC_AUTH_NULL, "null" },
{ RPC_AUTH_UNIX, "sys" },
{ RPC_AUTH_GSS_KRB5, "krb5" },
{ RPC_AUTH_GSS_KRB5I, "krb5i" },
{ RPC_AUTH_GSS_KRB5P, "krb5p" },
{ RPC_AUTH_GSS_LKEY, "lkey" },
{ RPC_AUTH_GSS_LKEYI, "lkeyi" },
{ RPC_AUTH_GSS_LKEYP, "lkeyp" },
{ RPC_AUTH_GSS_SPKM, "spkm" },
{ RPC_AUTH_GSS_SPKMI, "spkmi" },
{ RPC_AUTH_GSS_SPKMP, "spkmp" },
{ UINT_MAX, "unknown" }
};
int i;
for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
if (sec_flavours[i].flavour == flavour)
break;
}
return sec_flavours[i].str;
}
static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
int showdefaults)
{
struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
char *proto = NULL;
switch (sap->sa_family) {
case AF_INET:
switch (nfss->mountd_protocol) {
case IPPROTO_UDP:
proto = RPCBIND_NETID_UDP;
break;
case IPPROTO_TCP:
proto = RPCBIND_NETID_TCP;
break;
}
break;
case AF_INET6:
switch (nfss->mountd_protocol) {
case IPPROTO_UDP:
proto = RPCBIND_NETID_UDP6;
break;
case IPPROTO_TCP:
proto = RPCBIND_NETID_TCP6;
break;
}
break;
}
if (proto || showdefaults)
seq_printf(m, ",mountproto=%s", proto ?: "auto");
}
static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
int showdefaults)
{
struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
return;
switch (sap->sa_family) {
case AF_INET: {
struct sockaddr_in *sin = (struct sockaddr_in *)sap;
seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
break;
}
case AF_INET6: {
struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
break;
}
default:
if (showdefaults)
seq_printf(m, ",mountaddr=unspecified");
}
if (nfss->mountd_version || showdefaults)
seq_printf(m, ",mountvers=%u", nfss->mountd_version);
if ((nfss->mountd_port &&
nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
showdefaults)
seq_printf(m, ",mountport=%u", nfss->mountd_port);
nfs_show_mountd_netid(m, nfss, showdefaults);
}
#if IS_ENABLED(CONFIG_NFS_V4)
static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
int showdefaults)
{
struct nfs_client *clp = nfss->nfs_client;
seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
}
#else
static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
int showdefaults)
{
}
#endif
static void nfs_show_nfs_version(struct seq_file *m,
unsigned int version,
unsigned int minorversion)
{
seq_printf(m, ",vers=%u", version);
if (version == 4)
seq_printf(m, ".%u", minorversion);
}
/*
* Describe the mount options in force on this server representation
*/
static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
int showdefaults)
{
static const struct proc_nfs_info {
int flag;
const char *str;
const char *nostr;
} nfs_info[] = {
{ NFS_MOUNT_SOFT, ",soft", ",hard" },
{ NFS_MOUNT_POSIX, ",posix", "" },
{ NFS_MOUNT_NOCTO, ",nocto", "" },
{ NFS_MOUNT_NOAC, ",noac", "" },
{ NFS_MOUNT_NONLM, ",nolock", "" },
{ NFS_MOUNT_NOACL, ",noacl", "" },
{ NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
{ NFS_MOUNT_UNSHARED, ",nosharecache", "" },
{ NFS_MOUNT_NORESVPORT, ",noresvport", "" },
{ 0, NULL, NULL }
};
const struct proc_nfs_info *nfs_infop;
struct nfs_client *clp = nfss->nfs_client;
u32 version = clp->rpc_ops->version;
int local_flock, local_fcntl;
nfs_show_nfs_version(m, version, clp->cl_minorversion);
seq_printf(m, ",rsize=%u", nfss->rsize);
seq_printf(m, ",wsize=%u", nfss->wsize);
if (nfss->bsize != 0)
seq_printf(m, ",bsize=%u", nfss->bsize);
seq_printf(m, ",namlen=%u", nfss->namelen);
if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
if (nfss->flags & nfs_infop->flag)
seq_puts(m, nfs_infop->str);
else
seq_puts(m, nfs_infop->nostr);
}
rcu_read_lock();
seq_printf(m, ",proto=%s",
rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
rcu_read_unlock();
if (version == 4) {
if (nfss->port != NFS_PORT)
seq_printf(m, ",port=%u", nfss->port);
} else
if (nfss->port)
seq_printf(m, ",port=%u", nfss->port);
seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
if (version != 4)
nfs_show_mountd_options(m, nfss, showdefaults);
else
nfs_show_nfsv4_options(m, nfss, showdefaults);
if (nfss->options & NFS_OPTION_FSCACHE)
seq_printf(m, ",fsc");
if (nfss->options & NFS_OPTION_MIGRATION)
seq_printf(m, ",migration");
if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
seq_printf(m, ",lookupcache=none");
else
seq_printf(m, ",lookupcache=pos");
}
local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
if (!local_flock && !local_fcntl)
seq_printf(m, ",local_lock=none");
else if (local_flock && local_fcntl)
seq_printf(m, ",local_lock=all");
else if (local_flock)
seq_printf(m, ",local_lock=flock");
else
seq_printf(m, ",local_lock=posix");
}
/*
* Describe the mount options on this VFS mountpoint
*/
int nfs_show_options(struct seq_file *m, struct dentry *root)
{
struct nfs_server *nfss = NFS_SB(root->d_sb);
nfs_show_mount_options(m, nfss, 0);
rcu_read_lock();
seq_printf(m, ",addr=%s",
rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
RPC_DISPLAY_ADDR));
rcu_read_unlock();
return 0;
}
EXPORT_SYMBOL_GPL(nfs_show_options);
#if IS_ENABLED(CONFIG_NFS_V4)
#ifdef CONFIG_NFS_V4_1
static void show_sessions(struct seq_file *m, struct nfs_server *server)
{
if (nfs4_has_session(server->nfs_client))
seq_printf(m, ",sessions");
}
#else
static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
#endif
#endif
#ifdef CONFIG_NFS_V4_1
static void show_pnfs(struct seq_file *m, struct nfs_server *server)
{
seq_printf(m, ",pnfs=");
if (server->pnfs_curr_ld)
seq_printf(m, "%s", server->pnfs_curr_ld->name);
else
seq_printf(m, "not configured");
}
static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
{
if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
"date='%llu,%u'",
impl_id->name, impl_id->domain,
impl_id->date.seconds, impl_id->date.nseconds);
}
}
#else
#if IS_ENABLED(CONFIG_NFS_V4)
static void show_pnfs(struct seq_file *m, struct nfs_server *server)
{
}
#endif
static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
{
}
#endif
int nfs_show_devname(struct seq_file *m, struct dentry *root)
{
char *page = (char *) __get_free_page(GFP_KERNEL);
char *devname, *dummy;
int err = 0;
if (!page)
return -ENOMEM;
devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
if (IS_ERR(devname))
err = PTR_ERR(devname);
else
seq_escape(m, devname, " \t\n\\");
free_page((unsigned long)page);
return err;
}
EXPORT_SYMBOL_GPL(nfs_show_devname);
int nfs_show_path(struct seq_file *m, struct dentry *dentry)
{
seq_puts(m, "/");
return 0;
}
EXPORT_SYMBOL_GPL(nfs_show_path);
/*
* Present statistical information for this VFS mountpoint
*/
int nfs_show_stats(struct seq_file *m, struct dentry *root)
{
int i, cpu;
struct nfs_server *nfss = NFS_SB(root->d_sb);
struct rpc_auth *auth = nfss->client->cl_auth;
struct nfs_iostats totals = { };
seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
/*
* Display all mount option settings
*/
seq_printf(m, "\n\topts:\t");
seq_puts(m, sb_rdonly(root->d_sb) ? "ro" : "rw");
seq_puts(m, root->d_sb->s_flags & SB_SYNCHRONOUS ? ",sync" : "");
seq_puts(m, root->d_sb->s_flags & SB_NOATIME ? ",noatime" : "");
seq_puts(m, root->d_sb->s_flags & SB_NODIRATIME ? ",nodiratime" : "");
nfs_show_mount_options(m, nfss, 1);
seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
show_implementation_id(m, nfss);
seq_printf(m, "\n\tcaps:\t");
seq_printf(m, "caps=0x%x", nfss->caps);
seq_printf(m, ",wtmult=%u", nfss->wtmult);
seq_printf(m, ",dtsize=%u", nfss->dtsize);
seq_printf(m, ",bsize=%u", nfss->bsize);
seq_printf(m, ",namlen=%u", nfss->namelen);
#if IS_ENABLED(CONFIG_NFS_V4)
if (nfss->nfs_client->rpc_ops->version == 4) {
seq_printf(m, "\n\tnfsv4:\t");
seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]);
seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
show_sessions(m, nfss);
show_pnfs(m, nfss);
}
#endif
/*
* Display security flavor in effect for this mount
*/
seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
if (auth->au_flavor)
seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
/*
* Display superblock I/O counters
*/
for_each_possible_cpu(cpu) {
struct nfs_iostats *stats;
preempt_disable();
stats = per_cpu_ptr(nfss->io_stats, cpu);
for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
totals.events[i] += stats->events[i];
for (i = 0; i < __NFSIOS_BYTESMAX; i++)
totals.bytes[i] += stats->bytes[i];
#ifdef CONFIG_NFS_FSCACHE
for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
totals.fscache[i] += stats->fscache[i];
#endif
preempt_enable();
}
seq_printf(m, "\n\tevents:\t");
for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
seq_printf(m, "%lu ", totals.events[i]);
seq_printf(m, "\n\tbytes:\t");
for (i = 0; i < __NFSIOS_BYTESMAX; i++)
seq_printf(m, "%Lu ", totals.bytes[i]);
#ifdef CONFIG_NFS_FSCACHE
if (nfss->options & NFS_OPTION_FSCACHE) {
seq_printf(m, "\n\tfsc:\t");
for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
seq_printf(m, "%Lu ", totals.fscache[i]);
}
#endif
seq_printf(m, "\n");
rpc_print_iostats(m, nfss->client);
return 0;
}
EXPORT_SYMBOL_GPL(nfs_show_stats);
/*
* Begin unmount by attempting to remove all automounted mountpoints we added
* in response to xdev traversals and referrals
*/
void nfs_umount_begin(struct super_block *sb)
{
struct nfs_server *server;
struct rpc_clnt *rpc;
server = NFS_SB(sb);
/* -EIO all pending I/O */
rpc = server->client_acl;
if (!IS_ERR(rpc))
rpc_killall_tasks(rpc);
rpc = server->client;
if (!IS_ERR(rpc))
rpc_killall_tasks(rpc);
}
EXPORT_SYMBOL_GPL(nfs_umount_begin);
static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
{
struct nfs_parsed_mount_data *data;
data = kzalloc(sizeof(*data), GFP_KERNEL);
if (data) {
data->timeo = NFS_UNSPEC_TIMEO;
data->retrans = NFS_UNSPEC_RETRANS;
data->acregmin = NFS_DEF_ACREGMIN;
data->acregmax = NFS_DEF_ACREGMAX;
data->acdirmin = NFS_DEF_ACDIRMIN;
data->acdirmax = NFS_DEF_ACDIRMAX;
data->mount_server.port = NFS_UNSPEC_PORT;
data->nfs_server.port = NFS_UNSPEC_PORT;
data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
data->selected_flavor = RPC_AUTH_MAXFLAVOR;
data->minorversion = 0;
data->need_mount = true;
data->net = current->nsproxy->net_ns;
security_init_mnt_opts(&data->lsm_opts);
}
return data;
}
static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
{
if (data) {
kfree(data->client_address);
kfree(data->mount_server.hostname);
kfree(data->nfs_server.export_path);
kfree(data->nfs_server.hostname);
kfree(data->fscache_uniq);
security_free_mnt_opts(&data->lsm_opts);
kfree(data);
}
}
/*
* Sanity-check a server address provided by the mount command.
*
* Address family must be initialized, and address must not be
* the ANY address for that family.
*/
static int nfs_verify_server_address(struct sockaddr *addr)
{
switch (addr->sa_family) {
case AF_INET: {
struct sockaddr_in *sa = (struct sockaddr_in *)addr;
return sa->sin_addr.s_addr != htonl(INADDR_ANY);
}
case AF_INET6: {
struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
return !ipv6_addr_any(sa);
}
}
dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
return 0;
}
/*
* Select between a default port value and a user-specified port value.
* If a zero value is set, then autobind will be used.
*/
static void nfs_set_port(struct sockaddr *sap, int *port,
const unsigned short default_port)
{
if (*port == NFS_UNSPEC_PORT)
*port = default_port;
rpc_set_port(sap, *port);
}
/*
* Sanity check the NFS transport protocol.
*
*/
static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
{
switch (mnt->nfs_server.protocol) {
case XPRT_TRANSPORT_UDP:
case XPRT_TRANSPORT_TCP:
case XPRT_TRANSPORT_RDMA:
break;
default:
mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
}
}
/*
* For text based NFSv2/v3 mounts, the mount protocol transport default
* settings should depend upon the specified NFS transport.
*/
static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
{
nfs_validate_transport_protocol(mnt);
if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
return;
switch (mnt->nfs_server.protocol) {
case XPRT_TRANSPORT_UDP:
mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
break;
case XPRT_TRANSPORT_TCP:
case XPRT_TRANSPORT_RDMA:
mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
}
}
/*
* Add 'flavor' to 'auth_info' if not already present.
* Returns true if 'flavor' ends up in the list, false otherwise
*/
static bool nfs_auth_info_add(struct nfs_auth_info *auth_info,
rpc_authflavor_t flavor)
{
unsigned int i;
unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
/* make sure this flavor isn't already in the list */
for (i = 0; i < auth_info->flavor_len; i++) {
if (flavor == auth_info->flavors[i])
return true;
}
if (auth_info->flavor_len + 1 >= max_flavor_len) {
dfprintk(MOUNT, "NFS: too many sec= flavors\n");
return false;
}
auth_info->flavors[auth_info->flavor_len++] = flavor;
return true;
}
/*
* Return true if 'match' is in auth_info or auth_info is empty.
* Return false otherwise.
*/
bool nfs_auth_info_match(const struct nfs_auth_info *auth_info,
rpc_authflavor_t match)
{
int i;
if (!auth_info->flavor_len)
return true;
for (i = 0; i < auth_info->flavor_len; i++) {
if (auth_info->flavors[i] == match)
return true;
}
return false;
}
EXPORT_SYMBOL_GPL(nfs_auth_info_match);
/*
* Parse the value of the 'sec=' option.
*/
static int nfs_parse_security_flavors(char *value,
struct nfs_parsed_mount_data *mnt)
{
substring_t args[MAX_OPT_ARGS];
rpc_authflavor_t pseudoflavor;
char *p;
dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
while ((p = strsep(&value, ":")) != NULL) {
switch (match_token(p, nfs_secflavor_tokens, args)) {
case Opt_sec_none:
pseudoflavor = RPC_AUTH_NULL;
break;
case Opt_sec_sys:
pseudoflavor = RPC_AUTH_UNIX;
break;
case Opt_sec_krb5:
pseudoflavor = RPC_AUTH_GSS_KRB5;
break;
case Opt_sec_krb5i:
pseudoflavor = RPC_AUTH_GSS_KRB5I;
break;
case Opt_sec_krb5p:
pseudoflavor = RPC_AUTH_GSS_KRB5P;
break;
case Opt_sec_lkey:
pseudoflavor = RPC_AUTH_GSS_LKEY;
break;
case Opt_sec_lkeyi:
pseudoflavor = RPC_AUTH_GSS_LKEYI;
break;
case Opt_sec_lkeyp:
pseudoflavor = RPC_AUTH_GSS_LKEYP;
break;
case Opt_sec_spkm:
pseudoflavor = RPC_AUTH_GSS_SPKM;
break;
case Opt_sec_spkmi:
pseudoflavor = RPC_AUTH_GSS_SPKMI;
break;
case Opt_sec_spkmp:
pseudoflavor = RPC_AUTH_GSS_SPKMP;
break;
default:
dfprintk(MOUNT,
"NFS: sec= option '%s' not recognized\n", p);
return 0;
}
if (!nfs_auth_info_add(&mnt->auth_info, pseudoflavor))
return 0;
}
return 1;
}
static int nfs_parse_version_string(char *string,
struct nfs_parsed_mount_data *mnt,
substring_t *args)
{
mnt->flags &= ~NFS_MOUNT_VER3;
switch (match_token(string, nfs_vers_tokens, args)) {
case Opt_vers_2:
mnt->version = 2;
break;
case Opt_vers_3:
mnt->flags |= NFS_MOUNT_VER3;
mnt->version = 3;
break;
case Opt_vers_4:
/* Backward compatibility option. In future,
* the mount program should always supply
* a NFSv4 minor version number.
*/
mnt->version = 4;
break;
case Opt_vers_4_0:
mnt->version = 4;
mnt->minorversion = 0;
break;
case Opt_vers_4_1:
mnt->version = 4;
mnt->minorversion = 1;
break;
case Opt_vers_4_2:
mnt->version = 4;
mnt->minorversion = 2;
break;
default:
return 0;
}
return 1;
}
static int nfs_get_option_str(substring_t args[], char **option)
{
kfree(*option);
*option = match_strdup(args);
return !*option;
}
static int nfs_get_option_ul(substring_t args[], unsigned long *option)
{
int rc;
char *string;
string = match_strdup(args);
if (string == NULL)
return -ENOMEM;
rc = kstrtoul(string, 10, option);
kfree(string);
return rc;
}
static int nfs_get_option_ul_bound(substring_t args[], unsigned long *option,
unsigned long l_bound, unsigned long u_bound)
{
int ret;
ret = nfs_get_option_ul(args, option);
if (ret != 0)
return ret;
if (*option < l_bound || *option > u_bound)
return -ERANGE;
return 0;
}
/*
* Error-check and convert a string of mount options from user space into
* a data structure. The whole mount string is processed; bad options are
* skipped as they are encountered. If there were no errors, return 1;
* otherwise return 0 (zero).
*/
static int nfs_parse_mount_options(char *raw,
struct nfs_parsed_mount_data *mnt)
{
char *p, *string, *secdata;
int rc, sloppy = 0, invalid_option = 0;
unsigned short protofamily = AF_UNSPEC;
unsigned short mountfamily = AF_UNSPEC;
if (!raw) {
dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
return 1;
}
dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
secdata = alloc_secdata();
if (!secdata)
goto out_nomem;
rc = security_sb_copy_data(raw, secdata);
if (rc)
goto out_security_failure;
rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
if (rc)
goto out_security_failure;
free_secdata(secdata);
while ((p = strsep(&raw, ",")) != NULL) {
substring_t args[MAX_OPT_ARGS];
unsigned long option;
int token;
if (!*p)
continue;
dfprintk(MOUNT, "NFS: parsing nfs mount option '%s'\n", p);
token = match_token(p, nfs_mount_option_tokens, args);
switch (token) {
/*
* boolean options: foo/nofoo
*/
case Opt_soft:
mnt->flags |= NFS_MOUNT_SOFT;
break;
case Opt_hard:
mnt->flags &= ~NFS_MOUNT_SOFT;
break;
case Opt_posix:
mnt->flags |= NFS_MOUNT_POSIX;
break;
case Opt_noposix:
mnt->flags &= ~NFS_MOUNT_POSIX;
break;
case Opt_cto:
mnt->flags &= ~NFS_MOUNT_NOCTO;
break;
case Opt_nocto:
mnt->flags |= NFS_MOUNT_NOCTO;
break;
case Opt_ac:
mnt->flags &= ~NFS_MOUNT_NOAC;
break;
case Opt_noac:
mnt->flags |= NFS_MOUNT_NOAC;
break;
case Opt_lock:
mnt->flags &= ~NFS_MOUNT_NONLM;
mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
NFS_MOUNT_LOCAL_FCNTL);
break;
case Opt_nolock:
mnt->flags |= NFS_MOUNT_NONLM;
mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
NFS_MOUNT_LOCAL_FCNTL);
break;
case Opt_udp:
mnt->flags &= ~NFS_MOUNT_TCP;
mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
break;
case Opt_tcp:
mnt->flags |= NFS_MOUNT_TCP;
mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
break;
case Opt_rdma:
mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
xprt_load_transport(p);
break;
case Opt_acl:
mnt->flags &= ~NFS_MOUNT_NOACL;
break;
case Opt_noacl:
mnt->flags |= NFS_MOUNT_NOACL;
break;
case Opt_rdirplus:
mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
break;
case Opt_nordirplus:
mnt->flags |= NFS_MOUNT_NORDIRPLUS;
break;
case Opt_sharecache:
mnt->flags &= ~NFS_MOUNT_UNSHARED;
break;
case Opt_nosharecache:
mnt->flags |= NFS_MOUNT_UNSHARED;
break;
case Opt_resvport:
mnt->flags &= ~NFS_MOUNT_NORESVPORT;
break;
case Opt_noresvport:
mnt->flags |= NFS_MOUNT_NORESVPORT;
break;
case Opt_fscache:
mnt->options |= NFS_OPTION_FSCACHE;
kfree(mnt->fscache_uniq);
mnt->fscache_uniq = NULL;
break;
case Opt_nofscache:
mnt->options &= ~NFS_OPTION_FSCACHE;
kfree(mnt->fscache_uniq);
mnt->fscache_uniq = NULL;
break;
case Opt_migration:
mnt->options |= NFS_OPTION_MIGRATION;
break;
case Opt_nomigration:
mnt->options &= ~NFS_OPTION_MIGRATION;
break;
/*
* options that take numeric values
*/
case Opt_port:
if (nfs_get_option_ul(args, &option) ||
option > USHRT_MAX)
goto out_invalid_value;
mnt->nfs_server.port = option;
break;
case Opt_rsize:
if (nfs_get_option_ul(args, &option))
goto out_invalid_value;
mnt->rsize = option;
break;
case Opt_wsize:
if (nfs_get_option_ul(args, &option))
goto out_invalid_value;
mnt->wsize = option;
break;
case Opt_bsize:
if (nfs_get_option_ul(args, &option))
goto out_invalid_value;
mnt->bsize = option;
break;
case Opt_timeo:
if (nfs_get_option_ul_bound(args, &option, 1, INT_MAX))
goto out_invalid_value;
mnt->timeo = option;
break;
case Opt_retrans:
if (nfs_get_option_ul_bound(args, &option, 0, INT_MAX))
goto out_invalid_value;
mnt->retrans = option;
break;
case Opt_acregmin:
if (nfs_get_option_ul(args, &option))
goto out_invalid_value;
mnt->acregmin = option;
break;
case Opt_acregmax:
if (nfs_get_option_ul(args, &option))
goto out_invalid_value;
mnt->acregmax = option;
break;
case Opt_acdirmin:
if (nfs_get_option_ul(args, &option))
goto out_invalid_value;
mnt->acdirmin = option;
break;
case Opt_acdirmax:
if (nfs_get_option_ul(args, &option))
goto out_invalid_value;
mnt->acdirmax = option;
break;
case Opt_actimeo:
if (nfs_get_option_ul(args, &option))
goto out_invalid_value;
mnt->acregmin = mnt->acregmax =
mnt->acdirmin = mnt->acdirmax = option;
break;
case Opt_namelen:
if (nfs_get_option_ul(args, &option))
goto out_invalid_value;
mnt->namlen = option;
break;
case Opt_mountport:
if (nfs_get_option_ul(args, &option) ||
option > USHRT_MAX)
goto out_invalid_value;
mnt->mount_server.port = option;
break;
case Opt_mountvers:
if (nfs_get_option_ul(args, &option) ||
option < NFS_MNT_VERSION ||
option > NFS_MNT3_VERSION)
goto out_invalid_value;
mnt->mount_server.version = option;
break;
case Opt_minorversion:
if (nfs_get_option_ul(args, &option))
goto out_invalid_value;
if (option > NFS4_MAX_MINOR_VERSION)
goto out_invalid_value;
mnt->minorversion = option;
break;
/*
* options that take text values
*/
case Opt_nfsvers:
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
rc = nfs_parse_version_string(string, mnt, args);
kfree(string);
if (!rc)
goto out_invalid_value;
break;
case Opt_sec:
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
rc = nfs_parse_security_flavors(string, mnt);
kfree(string);
if (!rc) {
dfprintk(MOUNT, "NFS: unrecognized "
"security flavor\n");
return 0;
}
break;
case Opt_proto:
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
token = match_token(string,
nfs_xprt_protocol_tokens, args);
protofamily = AF_INET;
switch (token) {
case Opt_xprt_udp6:
protofamily = AF_INET6;
/* fall through */
case Opt_xprt_udp:
mnt->flags &= ~NFS_MOUNT_TCP;
mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
break;
case Opt_xprt_tcp6:
protofamily = AF_INET6;
/* fall through */
case Opt_xprt_tcp:
mnt->flags |= NFS_MOUNT_TCP;
mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
break;
case Opt_xprt_rdma6:
protofamily = AF_INET6;
/* fall through */
case Opt_xprt_rdma:
/* vector side protocols to TCP */
mnt->flags |= NFS_MOUNT_TCP;
mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
xprt_load_transport(string);
break;
default:
dfprintk(MOUNT, "NFS: unrecognized "
"transport protocol\n");
kfree(string);
return 0;
}
kfree(string);
break;
case Opt_mountproto:
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
token = match_token(string,
nfs_xprt_protocol_tokens, args);
kfree(string);
mountfamily = AF_INET;
switch (token) {
case Opt_xprt_udp6:
mountfamily = AF_INET6;
/* fall through */
case Opt_xprt_udp:
mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
break;
case Opt_xprt_tcp6:
mountfamily = AF_INET6;
/* fall through */
case Opt_xprt_tcp:
mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
break;
case Opt_xprt_rdma: /* not used for side protocols */
default:
dfprintk(MOUNT, "NFS: unrecognized "
"transport protocol\n");
return 0;
}
break;
case Opt_addr:
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
mnt->nfs_server.addrlen =
rpc_pton(mnt->net, string, strlen(string),
(struct sockaddr *)
&mnt->nfs_server.address,
sizeof(mnt->nfs_server.address));
kfree(string);
if (mnt->nfs_server.addrlen == 0)
goto out_invalid_address;
break;
case Opt_clientaddr:
if (nfs_get_option_str(args, &mnt->client_address))
goto out_nomem;
break;
case Opt_mounthost:
if (nfs_get_option_str(args,
&mnt->mount_server.hostname))
goto out_nomem;
break;
case Opt_mountaddr:
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
mnt->mount_server.addrlen =
rpc_pton(mnt->net, string, strlen(string),
(struct sockaddr *)
&mnt->mount_server.address,
sizeof(mnt->mount_server.address));
kfree(string);
if (mnt->mount_server.addrlen == 0)
goto out_invalid_address;
break;
case Opt_lookupcache:
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
token = match_token(string,
nfs_lookupcache_tokens, args);
kfree(string);
switch (token) {
case Opt_lookupcache_all:
mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
break;
case Opt_lookupcache_positive:
mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
break;
case Opt_lookupcache_none:
mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
break;
default:
dfprintk(MOUNT, "NFS: invalid "
"lookupcache argument\n");
return 0;
};
break;
case Opt_fscache_uniq:
if (nfs_get_option_str(args, &mnt->fscache_uniq))
goto out_nomem;
mnt->options |= NFS_OPTION_FSCACHE;
break;
case Opt_local_lock:
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
token = match_token(string, nfs_local_lock_tokens,
args);
kfree(string);
switch (token) {
case Opt_local_lock_all:
mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
NFS_MOUNT_LOCAL_FCNTL);
break;
case Opt_local_lock_flock:
mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
break;
case Opt_local_lock_posix:
mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
break;
case Opt_local_lock_none:
mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
NFS_MOUNT_LOCAL_FCNTL);
break;
default:
dfprintk(MOUNT, "NFS: invalid "
"local_lock argument\n");
return 0;
};
break;
/*
* Special options
*/
case Opt_sloppy:
sloppy = 1;
dfprintk(MOUNT, "NFS: relaxing parsing rules\n");
break;
case Opt_userspace:
case Opt_deprecated:
dfprintk(MOUNT, "NFS: ignoring mount option "
"'%s'\n", p);
break;
default:
invalid_option = 1;
dfprintk(MOUNT, "NFS: unrecognized mount option "
"'%s'\n", p);
}
}
if (!sloppy && invalid_option)
return 0;
if (mnt->minorversion && mnt->version != 4)
goto out_minorversion_mismatch;
if (mnt->options & NFS_OPTION_MIGRATION &&
(mnt->version != 4 || mnt->minorversion != 0))
goto out_migration_misuse;
/*
* verify that any proto=/mountproto= options match the address
* families in the addr=/mountaddr= options.
*/
if (protofamily != AF_UNSPEC &&
protofamily != mnt->nfs_server.address.ss_family)
goto out_proto_mismatch;
if (mountfamily != AF_UNSPEC) {
if (mnt->mount_server.addrlen) {
if (mountfamily != mnt->mount_server.address.ss_family)
goto out_mountproto_mismatch;
} else {
if (mountfamily != mnt->nfs_server.address.ss_family)
goto out_mountproto_mismatch;
}
}
return 1;
out_mountproto_mismatch:
printk(KERN_INFO "NFS: mount server address does not match mountproto= "
"option\n");
return 0;
out_proto_mismatch:
printk(KERN_INFO "NFS: server address does not match proto= option\n");
return 0;
out_invalid_address:
printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
return 0;
out_invalid_value:
printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
return 0;
out_minorversion_mismatch:
printk(KERN_INFO "NFS: mount option vers=%u does not support "
"minorversion=%u\n", mnt->version, mnt->minorversion);
return 0;
out_migration_misuse:
printk(KERN_INFO
"NFS: 'migration' not supported for this NFS version\n");
return 0;
out_nomem:
printk(KERN_INFO "NFS: not enough memory to parse option\n");
return 0;
out_security_failure:
free_secdata(secdata);
printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
return 0;
}
/*
* Ensure that a specified authtype in args->auth_info is supported by
* the server. Returns 0 and sets args->selected_flavor if it's ok, and
* -EACCES if not.
*/
static int nfs_verify_authflavors(struct nfs_parsed_mount_data *args,
rpc_authflavor_t *server_authlist, unsigned int count)
{
rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR;
bool found_auth_null = false;
unsigned int i;
/*
* If the sec= mount option is used, the specified flavor or AUTH_NULL
* must be in the list returned by the server.
*
* AUTH_NULL has a special meaning when it's in the server list - it
* means that the server will ignore the rpc creds, so any flavor
* can be used but still use the sec= that was specified.
*
* Note also that the MNT procedure in MNTv1 does not return a list
* of supported security flavors. In this case, nfs_mount() fabricates
* a security flavor list containing just AUTH_NULL.
*/
for (i = 0; i < count; i++) {
flavor = server_authlist[i];
if (nfs_auth_info_match(&args->auth_info, flavor))
goto out;
if (flavor == RPC_AUTH_NULL)
found_auth_null = true;
}
if (found_auth_null) {
flavor = args->auth_info.flavors[0];
goto out;
}
dfprintk(MOUNT,
"NFS: specified auth flavors not supported by server\n");
return -EACCES;
out:
args->selected_flavor = flavor;
dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->selected_flavor);
return 0;
}
/*
* Use the remote server's MOUNT service to request the NFS file handle
* corresponding to the provided path.
*/
static int nfs_request_mount(struct nfs_parsed_mount_data *args,
struct nfs_fh *root_fh,
rpc_authflavor_t *server_authlist,
unsigned int *server_authlist_len)
{
struct nfs_mount_request request = {
.sap = (struct sockaddr *)
&args->mount_server.address,
.dirpath = args->nfs_server.export_path,
.protocol = args->mount_server.protocol,
.fh = root_fh,
.noresvport = args->flags & NFS_MOUNT_NORESVPORT,
.auth_flav_len = server_authlist_len,
.auth_flavs = server_authlist,
.net = args->net,
};
int status;
if (args->mount_server.version == 0) {
switch (args->version) {
default:
args->mount_server.version = NFS_MNT3_VERSION;
break;
case 2:
args->mount_server.version = NFS_MNT_VERSION;
}
}
request.version = args->mount_server.version;
if (args->mount_server.hostname)
request.hostname = args->mount_server.hostname;
else
request.hostname = args->nfs_server.hostname;
/*
* Construct the mount server's address.
*/
if (args->mount_server.address.ss_family == AF_UNSPEC) {
memcpy(request.sap, &args->nfs_server.address,
args->nfs_server.addrlen);
args->mount_server.addrlen = args->nfs_server.addrlen;
}
request.salen = args->mount_server.addrlen;
nfs_set_port(request.sap, &args->mount_server.port, 0);
/*
* Now ask the mount server to map our export path
* to a file handle.
*/
status = nfs_mount(&request);
if (status != 0) {
dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
request.hostname, status);
return status;
}
return 0;
}
static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_info,
struct nfs_subversion *nfs_mod)
{
int status;
unsigned int i;
bool tried_auth_unix = false;
bool auth_null_in_list = false;
struct nfs_server *server = ERR_PTR(-EACCES);
struct nfs_parsed_mount_data *args = mount_info->parsed;
rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS];
unsigned int authlist_len = ARRAY_SIZE(authlist);
status = nfs_request_mount(args, mount_info->mntfh, authlist,
&authlist_len);
if (status)
return ERR_PTR(status);
/*
* Was a sec= authflavor specified in the options? First, verify
* whether the server supports it, and then just try to use it if so.
*/
if (args->auth_info.flavor_len > 0) {
status = nfs_verify_authflavors(args, authlist, authlist_len);
dfprintk(MOUNT, "NFS: using auth flavor %u\n",
args->selected_flavor);
if (status)
return ERR_PTR(status);
return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
}
/*
* No sec= option was provided. RFC 2623, section 2.7 suggests we
* SHOULD prefer the flavor listed first. However, some servers list
* AUTH_NULL first. Avoid ever choosing AUTH_NULL.
*/
for (i = 0; i < authlist_len; ++i) {
rpc_authflavor_t flavor;
struct rpcsec_gss_info info;
flavor = authlist[i];
switch (flavor) {
case RPC_AUTH_UNIX:
tried_auth_unix = true;
break;
case RPC_AUTH_NULL:
auth_null_in_list = true;
continue;
default:
if (rpcauth_get_gssinfo(flavor, &info) != 0)
continue;
/* Fallthrough */
}
dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
args->selected_flavor = flavor;
server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
if (!IS_ERR(server))
return server;
}
/*
* Nothing we tried so far worked. At this point, give up if we've
* already tried AUTH_UNIX or if the server's list doesn't contain
* AUTH_NULL
*/
if (tried_auth_unix || !auth_null_in_list)
return server;
/* Last chance! Try AUTH_UNIX */
dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
args->selected_flavor = RPC_AUTH_UNIX;
return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
}
struct dentry *nfs_try_mount(int flags, const char *dev_name,
struct nfs_mount_info *mount_info,
struct nfs_subversion *nfs_mod)
{
struct nfs_server *server;
if (mount_info->parsed->need_mount)
server = nfs_try_mount_request(mount_info, nfs_mod);
else
server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
if (IS_ERR(server))
return ERR_CAST(server);
return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
}
EXPORT_SYMBOL_GPL(nfs_try_mount);
/*
* Split "dev_name" into "hostname:export_path".
*
* The leftmost colon demarks the split between the server's hostname
* and the export path. If the hostname starts with a left square
* bracket, then it may contain colons.
*
* Note: caller frees hostname and export path, even on error.
*/
static int nfs_parse_devname(const char *dev_name,
char **hostname, size_t maxnamlen,
char **export_path, size_t maxpathlen)
{
size_t len;
char *end;
/* Is the host name protected with square brakcets? */
if (*dev_name == '[') {
end = strchr(++dev_name, ']');
if (end == NULL || end[1] != ':')
goto out_bad_devname;
len = end - dev_name;
end++;
} else {
char *comma;
end = strchr(dev_name, ':');
if (end == NULL)
goto out_bad_devname;
len = end - dev_name;
/* kill possible hostname list: not supported */
comma = strchr(dev_name, ',');
if (comma != NULL && comma < end)
*comma = 0;
}
if (len > maxnamlen)
goto out_hostname;
/* N.B. caller will free nfs_server.hostname in all cases */
*hostname = kstrndup(dev_name, len, GFP_KERNEL);
if (*hostname == NULL)
goto out_nomem;
len = strlen(++end);
if (len > maxpathlen)
goto out_path;
*export_path = kstrndup(end, len, GFP_KERNEL);
if (!*export_path)
goto out_nomem;
dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
return 0;
out_bad_devname:
dfprintk(MOUNT, "NFS: device name not in host:path format\n");
return -EINVAL;
out_nomem:
dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
return -ENOMEM;
out_hostname:
dfprintk(MOUNT, "NFS: server hostname too long\n");
return -ENAMETOOLONG;
out_path:
dfprintk(MOUNT, "NFS: export pathname too long\n");
return -ENAMETOOLONG;
}
/*
* Validate the NFS2/NFS3 mount data
* - fills in the mount root filehandle
*
* For option strings, user space handles the following behaviors:
*
* + DNS: mapping server host name to IP address ("addr=" option)
*
* + failure mode: how to behave if a mount request can't be handled
* immediately ("fg/bg" option)
*
* + retry: how often to retry a mount request ("retry=" option)
*
* + breaking back: trying proto=udp after proto=tcp, v2 after v3,
* mountproto=tcp after mountproto=udp, and so on
*/
static int nfs23_validate_mount_data(void *options,
struct nfs_parsed_mount_data *args,
struct nfs_fh *mntfh,
const char *dev_name)
{
struct nfs_mount_data *data = (struct nfs_mount_data *)options;
struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
if (data == NULL)
goto out_no_data;
args->version = NFS_DEFAULT_VERSION;
switch (data->version) {
case 1:
data->namlen = 0; /* fall through */
case 2:
data->bsize = 0; /* fall through */
case 3:
if (data->flags & NFS_MOUNT_VER3)
goto out_no_v3;
data->root.size = NFS2_FHSIZE;
memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
/* Turn off security negotiation */
extra_flags |= NFS_MOUNT_SECFLAVOUR;
/* fall through */
case 4:
if (data->flags & NFS_MOUNT_SECFLAVOUR)
goto out_no_sec;
/* fall through */
case 5:
memset(data->context, 0, sizeof(data->context));
/* fall through */
case 6:
if (data->flags & NFS_MOUNT_VER3) {
if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
goto out_invalid_fh;
mntfh->size = data->root.size;
args->version = 3;
} else {
mntfh->size = NFS2_FHSIZE;
args->version = 2;
}
memcpy(mntfh->data, data->root.data, mntfh->size);
if (mntfh->size < sizeof(mntfh->data))
memset(mntfh->data + mntfh->size, 0,
sizeof(mntfh->data) - mntfh->size);
/*
* Translate to nfs_parsed_mount_data, which nfs_fill_super
* can deal with.
*/
args->flags = data->flags & NFS_MOUNT_FLAGMASK;
args->flags |= extra_flags;
args->rsize = data->rsize;
args->wsize = data->wsize;
args->timeo = data->timeo;
args->retrans = data->retrans;
args->acregmin = data->acregmin;
args->acregmax = data->acregmax;
args->acdirmin = data->acdirmin;
args->acdirmax = data->acdirmax;
args->need_mount = false;
memcpy(sap, &data->addr, sizeof(data->addr));
args->nfs_server.addrlen = sizeof(data->addr);
args->nfs_server.port = ntohs(data->addr.sin_port);
if (!nfs_verify_server_address(sap))
goto out_no_address;
if (!(data->flags & NFS_MOUNT_TCP))
args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
/* N.B. caller will free nfs_server.hostname in all cases */
args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
args->namlen = data->namlen;
args->bsize = data->bsize;
if (data->flags & NFS_MOUNT_SECFLAVOUR)
args->selected_flavor = data->pseudoflavor;
else
args->selected_flavor = RPC_AUTH_UNIX;
if (!args->nfs_server.hostname)
goto out_nomem;
if (!(data->flags & NFS_MOUNT_NONLM))
args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
NFS_MOUNT_LOCAL_FCNTL);
else
args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
NFS_MOUNT_LOCAL_FCNTL);
/*
* The legacy version 6 binary mount data from userspace has a
* field used only to transport selinux information into the
* the kernel. To continue to support that functionality we
* have a touch of selinux knowledge here in the NFS code. The
* userspace code converted context=blah to just blah so we are
* converting back to the full string selinux understands.
*/
if (data->context[0]){
#ifdef CONFIG_SECURITY_SELINUX
int rc;
char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
if (!opts_str)
return -ENOMEM;
strcpy(opts_str, "context=");
data->context[NFS_MAX_CONTEXT_LEN] = '\0';
strcat(opts_str, &data->context[0]);
rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
kfree(opts_str);
if (rc)
return rc;
#else
return -EINVAL;
#endif
}
break;
default:
return NFS_TEXT_DATA;
}
return 0;
out_no_data:
dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
return -EINVAL;
out_no_v3:
dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
data->version);
return -EINVAL;
out_no_sec:
dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
return -EINVAL;
out_nomem:
dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
return -ENOMEM;
out_no_address:
dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
return -EINVAL;
out_invalid_fh:
dfprintk(MOUNT, "NFS: invalid root filehandle\n");
return -EINVAL;
}
#if IS_ENABLED(CONFIG_NFS_V4)
static int nfs_validate_mount_data(struct file_system_type *fs_type,
void *options,
struct nfs_parsed_mount_data *args,
struct nfs_fh *mntfh,
const char *dev_name)
{
if (fs_type == &nfs_fs_type)
return nfs23_validate_mount_data(options, args, mntfh, dev_name);
return nfs4_validate_mount_data(options, args, dev_name);
}
#else
static int nfs_validate_mount_data(struct file_system_type *fs_type,
void *options,
struct nfs_parsed_mount_data *args,
struct nfs_fh *mntfh,
const char *dev_name)
{
return nfs23_validate_mount_data(options, args, mntfh, dev_name);
}
#endif
static int nfs_validate_text_mount_data(void *options,
struct nfs_parsed_mount_data *args,
const char *dev_name)
{
int port = 0;
int max_namelen = PAGE_SIZE;
int max_pathlen = NFS_MAXPATHLEN;
struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
if (nfs_parse_mount_options((char *)options, args) == 0)
return -EINVAL;
if (!nfs_verify_server_address(sap))
goto out_no_address;
if (args->version == 4) {
#if IS_ENABLED(CONFIG_NFS_V4)
port = NFS_PORT;
max_namelen = NFS4_MAXNAMLEN;
max_pathlen = NFS4_MAXPATHLEN;
nfs_validate_transport_protocol(args);
if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
goto out_invalid_transport_udp;
nfs4_validate_mount_flags(args);
#else
goto out_v4_not_compiled;
#endif /* CONFIG_NFS_V4 */
} else
nfs_set_mount_transport_protocol(args);
nfs_set_port(sap, &args->nfs_server.port, port);
return nfs_parse_devname(dev_name,
&args->nfs_server.hostname,
max_namelen,
&args->nfs_server.export_path,
max_pathlen);
#if !IS_ENABLED(CONFIG_NFS_V4)
out_v4_not_compiled:
dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
return -EPROTONOSUPPORT;
#else
out_invalid_transport_udp:
dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
return -EINVAL;
#endif /* !CONFIG_NFS_V4 */
out_no_address:
dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
return -EINVAL;
}
#define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
| NFS_MOUNT_SECURE \
| NFS_MOUNT_TCP \
| NFS_MOUNT_VER3 \
| NFS_MOUNT_KERBEROS \
| NFS_MOUNT_NONLM \
| NFS_MOUNT_BROKEN_SUID \
| NFS_MOUNT_STRICTLOCK \
| NFS_MOUNT_LEGACY_INTERFACE)
#define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \
~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT))
static int
nfs_compare_remount_data(struct nfs_server *nfss,
struct nfs_parsed_mount_data *data)
{
if ((data->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK ||
data->rsize != nfss->rsize ||
data->wsize != nfss->wsize ||
data->version != nfss->nfs_client->rpc_ops->version ||
data->minorversion != nfss->nfs_client->cl_minorversion ||
data->retrans != nfss->client->cl_timeout->to_retries ||
!nfs_auth_info_match(&data->auth_info, nfss->client->cl_auth->au_flavor) ||
data->acregmin != nfss->acregmin / HZ ||
data->acregmax != nfss->acregmax / HZ ||
data->acdirmin != nfss->acdirmin / HZ ||
data->acdirmax != nfss->acdirmax / HZ ||
data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
data->nfs_server.port != nfss->port ||
data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
!rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
(struct sockaddr *)&nfss->nfs_client->cl_addr))
return -EINVAL;
return 0;
}
int
nfs_remount(struct super_block *sb, int *flags, char *raw_data)
{
int error;
struct nfs_server *nfss = sb->s_fs_info;
struct nfs_parsed_mount_data *data;
struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
u32 nfsvers = nfss->nfs_client->rpc_ops->version;
sync_filesystem(sb);
/*
* Userspace mount programs that send binary options generally send
* them populated with default values. We have no way to know which
* ones were explicitly specified. Fall back to legacy behavior and
* just return success.
*/
if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
(nfsvers <= 3 && (!options || (options->version >= 1 &&
options->version <= 6))))
return 0;
data = kzalloc(sizeof(*data), GFP_KERNEL);
if (data == NULL)
return -ENOMEM;
/* fill out struct with values from existing mount */
data->flags = nfss->flags;
data->rsize = nfss->rsize;
data->wsize = nfss->wsize;
data->retrans = nfss->client->cl_timeout->to_retries;
data->selected_flavor = nfss->client->cl_auth->au_flavor;
data->acregmin = nfss->acregmin / HZ;
data->acregmax = nfss->acregmax / HZ;
data->acdirmin = nfss->acdirmin / HZ;
data->acdirmax = nfss->acdirmax / HZ;
data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
data->nfs_server.port = nfss->port;
data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
data->version = nfsvers;
data->minorversion = nfss->nfs_client->cl_minorversion;
data->net = current->nsproxy->net_ns;
memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
data->nfs_server.addrlen);
/* overwrite those values with any that were specified */
error = -EINVAL;
if (!nfs_parse_mount_options((char *)options, data))
goto out;
/*
* noac is a special case. It implies -o sync, but that's not
* necessarily reflected in the mtab options. do_remount_sb
* will clear SB_SYNCHRONOUS if -o sync wasn't specified in the
* remount options, so we have to explicitly reset it.
*/
if (data->flags & NFS_MOUNT_NOAC)
*flags |= SB_SYNCHRONOUS;
/* compare new mount options with old ones */
error = nfs_compare_remount_data(nfss, data);
out:
kfree(data);
return error;
}
EXPORT_SYMBOL_GPL(nfs_remount);
/*
* Initialise the common bits of the superblock
*/
static void nfs_initialise_sb(struct super_block *sb)
{
struct nfs_server *server = NFS_SB(sb);
sb->s_magic = NFS_SUPER_MAGIC;
/* We probably want something more informative here */
snprintf(sb->s_id, sizeof(sb->s_id),
"%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
if (sb->s_blocksize == 0)
sb->s_blocksize = nfs_block_bits(server->wsize,
&sb->s_blocksize_bits);
nfs_super_set_maxbytes(sb, server->maxfilesize);
}
/*
* Finish setting up an NFS2/3 superblock
*/
void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
{
struct nfs_parsed_mount_data *data = mount_info->parsed;
struct nfs_server *server = NFS_SB(sb);
sb->s_blocksize_bits = 0;
sb->s_blocksize = 0;
sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
sb->s_op = server->nfs_client->cl_nfs_mod->sops;
if (data && data->bsize)
sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
if (server->nfs_client->rpc_ops->version != 2) {
/* The VFS shouldn't apply the umask to mode bits. We will do
* so ourselves when necessary.
*/
sb->s_flags |= SB_POSIXACL;
sb->s_time_gran = 1;
sb->s_export_op = &nfs_export_ops;
}
nfs_initialise_sb(sb);
}
EXPORT_SYMBOL_GPL(nfs_fill_super);
/*
* Finish setting up a cloned NFS2/3/4 superblock
*/
static void nfs_clone_super(struct super_block *sb,
struct nfs_mount_info *mount_info)
{
const struct super_block *old_sb = mount_info->cloned->sb;
struct nfs_server *server = NFS_SB(sb);
sb->s_blocksize_bits = old_sb->s_blocksize_bits;
sb->s_blocksize = old_sb->s_blocksize;
sb->s_maxbytes = old_sb->s_maxbytes;
sb->s_xattr = old_sb->s_xattr;
sb->s_op = old_sb->s_op;
sb->s_time_gran = 1;
sb->s_export_op = old_sb->s_export_op;
if (server->nfs_client->rpc_ops->version != 2) {
/* The VFS shouldn't apply the umask to mode bits. We will do
* so ourselves when necessary.
*/
sb->s_flags |= SB_POSIXACL;
}
nfs_initialise_sb(sb);
}
static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
{
const struct nfs_server *a = s->s_fs_info;
const struct rpc_clnt *clnt_a = a->client;
const struct rpc_clnt *clnt_b = b->client;
if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
goto Ebusy;
if (a->nfs_client != b->nfs_client)
goto Ebusy;
if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK)
goto Ebusy;
if (a->wsize != b->wsize)
goto Ebusy;
if (a->rsize != b->rsize)
goto Ebusy;
if (a->acregmin != b->acregmin)
goto Ebusy;
if (a->acregmax != b->acregmax)
goto Ebusy;
if (a->acdirmin != b->acdirmin)
goto Ebusy;
if (a->acdirmax != b->acdirmax)
goto Ebusy;
if (b->auth_info.flavor_len > 0 &&
clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
goto Ebusy;
return 1;
Ebusy:
return 0;
}
struct nfs_sb_mountdata {
struct nfs_server *server;
int mntflags;
};
static int nfs_set_super(struct super_block *s, void *data)
{
struct nfs_sb_mountdata *sb_mntdata = data;
struct nfs_server *server = sb_mntdata->server;
int ret;
s->s_flags = sb_mntdata->mntflags;
s->s_fs_info = server;
s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
ret = set_anon_super(s, server);
if (ret == 0)
server->s_dev = s->s_dev;
return ret;
}
static int nfs_compare_super_address(struct nfs_server *server1,
struct nfs_server *server2)
{
struct sockaddr *sap1, *sap2;
struct rpc_xprt *xprt1 = server1->client->cl_xprt;
struct rpc_xprt *xprt2 = server2->client->cl_xprt;
if (!net_eq(xprt1->xprt_net, xprt2->xprt_net))
return 0;
sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
if (sap1->sa_family != sap2->sa_family)
return 0;
switch (sap1->sa_family) {
case AF_INET: {
struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
return 0;
if (sin1->sin_port != sin2->sin_port)
return 0;
break;
}
case AF_INET6: {
struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
return 0;
if (sin1->sin6_port != sin2->sin6_port)
return 0;
break;
}
default:
return 0;
}
return 1;
}
static int nfs_compare_super(struct super_block *sb, void *data)
{
struct nfs_sb_mountdata *sb_mntdata = data;
struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
int mntflags = sb_mntdata->mntflags;
if (!nfs_compare_super_address(old, server))
return 0;
/* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
if (old->flags & NFS_MOUNT_UNSHARED)
return 0;
if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
return 0;
return nfs_compare_mount_options(sb, server, mntflags);
}
#ifdef CONFIG_NFS_FSCACHE
static void nfs_get_cache_cookie(struct super_block *sb,
struct nfs_parsed_mount_data *parsed,
struct nfs_clone_mount *cloned)
{
struct nfs_server *nfss = NFS_SB(sb);
char *uniq = NULL;
int ulen = 0;
nfss->fscache_key = NULL;
nfss->fscache = NULL;
if (parsed) {
if (!(parsed->options & NFS_OPTION_FSCACHE))
return;
if (parsed->fscache_uniq) {
uniq = parsed->fscache_uniq;
ulen = strlen(parsed->fscache_uniq);
}
} else if (cloned) {
struct nfs_server *mnt_s = NFS_SB(cloned->sb);
if (!(mnt_s->options & NFS_OPTION_FSCACHE))
return;
if (mnt_s->fscache_key) {
uniq = mnt_s->fscache_key->key.uniquifier;
ulen = mnt_s->fscache_key->key.uniq_len;
};
} else
return;
nfs_fscache_get_super_cookie(sb, uniq, ulen);
}
#else
static void nfs_get_cache_cookie(struct super_block *sb,
struct nfs_parsed_mount_data *parsed,
struct nfs_clone_mount *cloned)
{
}
#endif
int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
struct nfs_mount_info *mount_info)
{
int error;
unsigned long kflags = 0, kflags_out = 0;
if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
kflags |= SECURITY_LSM_NATIVE_LABELS;
error = security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts,
kflags, &kflags_out);
if (error)
goto err;
if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
!(kflags_out & SECURITY_LSM_NATIVE_LABELS))
NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
err:
return error;
}
EXPORT_SYMBOL_GPL(nfs_set_sb_security);
int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
struct nfs_mount_info *mount_info)
{
int error;
unsigned long kflags = 0, kflags_out = 0;
/* clone any lsm security options from the parent to the new sb */
if (d_inode(mntroot)->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
return -ESTALE;
if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
kflags |= SECURITY_LSM_NATIVE_LABELS;
error = security_sb_clone_mnt_opts(mount_info->cloned->sb, s, kflags,
&kflags_out);
if (error)
return error;
if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
!(kflags_out & SECURITY_LSM_NATIVE_LABELS))
NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
return 0;
}
EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
struct dentry *nfs_fs_mount_common(struct nfs_server *server,
int flags, const char *dev_name,
struct nfs_mount_info *mount_info,
struct nfs_subversion *nfs_mod)
{
struct super_block *s;
struct dentry *mntroot = ERR_PTR(-ENOMEM);
int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
struct nfs_sb_mountdata sb_mntdata = {
.mntflags = flags,
.server = server,
};
int error;
if (server->flags & NFS_MOUNT_UNSHARED)
compare_super = NULL;
/* -o noac implies -o sync */
if (server->flags & NFS_MOUNT_NOAC)
sb_mntdata.mntflags |= SB_SYNCHRONOUS;
if (mount_info->cloned != NULL && mount_info->cloned->sb != NULL)
if (mount_info->cloned->sb->s_flags & SB_SYNCHRONOUS)
sb_mntdata.mntflags |= SB_SYNCHRONOUS;
/* Get a superblock - note that we may end up sharing one that already exists */
s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
if (IS_ERR(s)) {
mntroot = ERR_CAST(s);
goto out_err_nosb;
}
if (s->s_fs_info != server) {
nfs_free_server(server);
server = NULL;
} else {
error = super_setup_bdi_name(s, "%u:%u", MAJOR(server->s_dev),
MINOR(server->s_dev));
if (error) {
mntroot = ERR_PTR(error);
goto error_splat_super;
}
s->s_bdi->ra_pages = server->rpages * NFS_MAX_READAHEAD;
server->super = s;
}
if (!s->s_root) {
/* initial superblock/root creation */
mount_info->fill_super(s, mount_info);
nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
if (!(server->flags & NFS_MOUNT_UNSHARED))
s->s_iflags |= SB_I_MULTIROOT;
}
mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
if (IS_ERR(mntroot))
goto error_splat_super;
error = mount_info->set_security(s, mntroot, mount_info);
if (error)
goto error_splat_root;
s->s_flags |= SB_ACTIVE;
out:
return mntroot;
out_err_nosb:
nfs_free_server(server);
goto out;
error_splat_root:
dput(mntroot);
mntroot = ERR_PTR(error);
error_splat_super:
deactivate_locked_super(s);
goto out;
}
EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
int flags, const char *dev_name, void *raw_data)
{
struct nfs_mount_info mount_info = {
.fill_super = nfs_fill_super,
.set_security = nfs_set_sb_security,
};
struct dentry *mntroot = ERR_PTR(-ENOMEM);
struct nfs_subversion *nfs_mod;
int error;
mount_info.parsed = nfs_alloc_parsed_mount_data();
mount_info.mntfh = nfs_alloc_fhandle();
if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
goto out;
/* Validate the mount data */
error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
if (error == NFS_TEXT_DATA)
error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
if (error < 0) {
mntroot = ERR_PTR(error);
goto out;
}
nfs_mod = get_nfs_version(mount_info.parsed->version);
if (IS_ERR(nfs_mod)) {
mntroot = ERR_CAST(nfs_mod);
goto out;
}
mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
put_nfs_version(nfs_mod);
out:
nfs_free_parsed_mount_data(mount_info.parsed);
nfs_free_fhandle(mount_info.mntfh);
return mntroot;
}
EXPORT_SYMBOL_GPL(nfs_fs_mount);
/*
* Destroy an NFS2/3 superblock
*/
void nfs_kill_super(struct super_block *s)
{
struct nfs_server *server = NFS_SB(s);
dev_t dev = s->s_dev;
generic_shutdown_super(s);
nfs_fscache_release_super_cookie(s);
nfs_free_server(server);
free_anon_bdev(dev);
}
EXPORT_SYMBOL_GPL(nfs_kill_super);
/*
* Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
*/
static struct dentry *
nfs_xdev_mount(struct file_system_type *fs_type, int flags,
const char *dev_name, void *raw_data)
{
struct nfs_clone_mount *data = raw_data;
struct nfs_mount_info mount_info = {
.fill_super = nfs_clone_super,
.set_security = nfs_clone_sb_security,
.cloned = data,
};
struct nfs_server *server;
struct dentry *mntroot = ERR_PTR(-ENOMEM);
struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
dprintk("--> nfs_xdev_mount()\n");
mount_info.mntfh = mount_info.cloned->fh;
/* create a new volume representation */
server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
if (IS_ERR(server))
mntroot = ERR_CAST(server);
else
mntroot = nfs_fs_mount_common(server, flags,
dev_name, &mount_info, nfs_mod);
dprintk("<-- nfs_xdev_mount() = %ld\n",
IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
return mntroot;
}
#if IS_ENABLED(CONFIG_NFS_V4)
static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
{
args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
}
/*
* Validate NFSv4 mount options
*/
static int nfs4_validate_mount_data(void *options,
struct nfs_parsed_mount_data *args,
const char *dev_name)
{
struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
char *c;
if (data == NULL)
goto out_no_data;
args->version = 4;
switch (data->version) {
case 1:
if (data->host_addrlen > sizeof(args->nfs_server.address))
goto out_no_address;
if (data->host_addrlen == 0)
goto out_no_address;
args->nfs_server.addrlen = data->host_addrlen;
if (copy_from_user(sap, data->host_addr, data->host_addrlen))
return -EFAULT;
if (!nfs_verify_server_address(sap))
goto out_no_address;
args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
if (data->auth_flavourlen) {
rpc_authflavor_t pseudoflavor;
if (data->auth_flavourlen > 1)
goto out_inval_auth;
if (copy_from_user(&pseudoflavor,
data->auth_flavours,
sizeof(pseudoflavor)))
return -EFAULT;
args->selected_flavor = pseudoflavor;
} else
args->selected_flavor = RPC_AUTH_UNIX;
c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
if (IS_ERR(c))
return PTR_ERR(c);
args->nfs_server.hostname = c;
c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
if (IS_ERR(c))
return PTR_ERR(c);
args->nfs_server.export_path = c;
dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
c = strndup_user(data->client_addr.data, 16);
if (IS_ERR(c))
return PTR_ERR(c);
args->client_address = c;
/*
* Translate to nfs_parsed_mount_data, which nfs4_fill_super
* can deal with.
*/
args->flags = data->flags & NFS4_MOUNT_FLAGMASK;
args->rsize = data->rsize;
args->wsize = data->wsize;
args->timeo = data->timeo;
args->retrans = data->retrans;
args->acregmin = data->acregmin;
args->acregmax = data->acregmax;
args->acdirmin = data->acdirmin;
args->acdirmax = data->acdirmax;
args->nfs_server.protocol = data->proto;
nfs_validate_transport_protocol(args);
if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
goto out_invalid_transport_udp;
break;
default:
return NFS_TEXT_DATA;
}
return 0;
out_no_data:
dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
return -EINVAL;
out_inval_auth:
dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
data->auth_flavourlen);
return -EINVAL;
out_no_address:
dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
return -EINVAL;
out_invalid_transport_udp:
dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
return -EINVAL;
}
/*
* NFS v4 module parameters need to stay in the
* NFS client for backwards compatibility
*/
unsigned int nfs_callback_set_tcpport;
unsigned short nfs_callback_nr_threads;
/* Default cache timeout is 10 minutes */
unsigned int nfs_idmap_cache_timeout = 600;
/* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
bool nfs4_disable_idmapping = true;
unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
unsigned short max_session_cb_slots = NFS4_DEF_CB_SLOT_TABLE_SIZE;
unsigned short send_implementation_id = 1;
char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
bool recover_lost_locks = false;
EXPORT_SYMBOL_GPL(nfs_callback_nr_threads);
EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
EXPORT_SYMBOL_GPL(max_session_slots);
EXPORT_SYMBOL_GPL(max_session_cb_slots);
EXPORT_SYMBOL_GPL(send_implementation_id);
EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
EXPORT_SYMBOL_GPL(recover_lost_locks);
#define NFS_CALLBACK_MAXPORTNR (65535U)
static int param_set_portnr(const char *val, const struct kernel_param *kp)
{
unsigned long num;
int ret;
if (!val)
return -EINVAL;
ret = kstrtoul(val, 0, &num);
if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
return -EINVAL;
*((unsigned int *)kp->arg) = num;
return 0;
}
static const struct kernel_param_ops param_ops_portnr = {
.set = param_set_portnr,
.get = param_get_uint,
};
#define param_check_portnr(name, p) __param_check(name, p, unsigned int);
module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
module_param_named(callback_nr_threads, nfs_callback_nr_threads, ushort, 0644);
MODULE_PARM_DESC(callback_nr_threads, "Number of threads that will be "
"assigned to the NFSv4 callback channels.");
module_param(nfs_idmap_cache_timeout, int, 0644);
module_param(nfs4_disable_idmapping, bool, 0644);
module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
NFS4_CLIENT_ID_UNIQ_LEN, 0600);
MODULE_PARM_DESC(nfs4_disable_idmapping,
"Turn off NFSv4 idmapping when using 'sec=sys'");
module_param(max_session_slots, ushort, 0644);
MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
"requests the client will negotiate");
module_param(max_session_cb_slots, ushort, 0644);
MODULE_PARM_DESC(max_session_cb_slots, "Maximum number of parallel NFSv4.1 "
"callbacks the client will process for a given server");
module_param(send_implementation_id, ushort, 0644);
MODULE_PARM_DESC(send_implementation_id,
"Send implementation ID with NFSv4.1 exchange_id");
MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
module_param(recover_lost_locks, bool, 0644);
MODULE_PARM_DESC(recover_lost_locks,
"If the server reports that a lock might be lost, "
"try to recover it risking data corruption.");
#endif /* CONFIG_NFS_V4 */