linux/fs/nfsd/nfsctl.c
Vasily Averin 2317dc557a race of nfsd inetaddr notifiers vs nn->nfsd_serv change
nfsd_inet[6]addr_event uses nn->nfsd_serv without taking nfsd_mutex,
which can be changed during execution of notifiers and crash the host.

Moreover if notifiers were enabled in one net namespace they are enabled
in all other net namespaces, from creation until destruction.

This patch allows notifiers to access nn->nfsd_serv only after the
pointer is correctly initialized and delays cleanup until notifiers are
no longer in use.

Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Tested-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-11-27 16:45:11 -05:00

1339 lines
34 KiB
C

/*
* Syscall interface to knfsd.
*
* Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
*/
#include <linux/slab.h>
#include <linux/namei.h>
#include <linux/ctype.h>
#include <linux/sunrpc/svcsock.h>
#include <linux/lockd/lockd.h>
#include <linux/sunrpc/addr.h>
#include <linux/sunrpc/gss_api.h>
#include <linux/sunrpc/gss_krb5_enctypes.h>
#include <linux/sunrpc/rpc_pipe_fs.h>
#include <linux/module.h>
#include "idmap.h"
#include "nfsd.h"
#include "cache.h"
#include "state.h"
#include "netns.h"
#include "pnfs.h"
/*
* We have a single directory with several nodes in it.
*/
enum {
NFSD_Root = 1,
NFSD_List,
NFSD_Export_features,
NFSD_Fh,
NFSD_FO_UnlockIP,
NFSD_FO_UnlockFS,
NFSD_Threads,
NFSD_Pool_Threads,
NFSD_Pool_Stats,
NFSD_Reply_Cache_Stats,
NFSD_Versions,
NFSD_Ports,
NFSD_MaxBlkSize,
NFSD_MaxConnections,
NFSD_SupportedEnctypes,
/*
* The below MUST come last. Otherwise we leave a hole in nfsd_files[]
* with !CONFIG_NFSD_V4 and simple_fill_super() goes oops
*/
#ifdef CONFIG_NFSD_V4
NFSD_Leasetime,
NFSD_Gracetime,
NFSD_RecoveryDir,
NFSD_V4EndGrace,
#endif
};
/*
* write() for these nodes.
*/
static ssize_t write_filehandle(struct file *file, char *buf, size_t size);
static ssize_t write_unlock_ip(struct file *file, char *buf, size_t size);
static ssize_t write_unlock_fs(struct file *file, char *buf, size_t size);
static ssize_t write_threads(struct file *file, char *buf, size_t size);
static ssize_t write_pool_threads(struct file *file, char *buf, size_t size);
static ssize_t write_versions(struct file *file, char *buf, size_t size);
static ssize_t write_ports(struct file *file, char *buf, size_t size);
static ssize_t write_maxblksize(struct file *file, char *buf, size_t size);
static ssize_t write_maxconn(struct file *file, char *buf, size_t size);
#ifdef CONFIG_NFSD_V4
static ssize_t write_leasetime(struct file *file, char *buf, size_t size);
static ssize_t write_gracetime(struct file *file, char *buf, size_t size);
static ssize_t write_recoverydir(struct file *file, char *buf, size_t size);
static ssize_t write_v4_end_grace(struct file *file, char *buf, size_t size);
#endif
static ssize_t (*write_op[])(struct file *, char *, size_t) = {
[NFSD_Fh] = write_filehandle,
[NFSD_FO_UnlockIP] = write_unlock_ip,
[NFSD_FO_UnlockFS] = write_unlock_fs,
[NFSD_Threads] = write_threads,
[NFSD_Pool_Threads] = write_pool_threads,
[NFSD_Versions] = write_versions,
[NFSD_Ports] = write_ports,
[NFSD_MaxBlkSize] = write_maxblksize,
[NFSD_MaxConnections] = write_maxconn,
#ifdef CONFIG_NFSD_V4
[NFSD_Leasetime] = write_leasetime,
[NFSD_Gracetime] = write_gracetime,
[NFSD_RecoveryDir] = write_recoverydir,
[NFSD_V4EndGrace] = write_v4_end_grace,
#endif
};
static ssize_t nfsctl_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
{
ino_t ino = file_inode(file)->i_ino;
char *data;
ssize_t rv;
if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
return -EINVAL;
data = simple_transaction_get(file, buf, size);
if (IS_ERR(data))
return PTR_ERR(data);
rv = write_op[ino](file, data, size);
if (rv >= 0) {
simple_transaction_set(file, rv);
rv = size;
}
return rv;
}
static ssize_t nfsctl_transaction_read(struct file *file, char __user *buf, size_t size, loff_t *pos)
{
if (! file->private_data) {
/* An attempt to read a transaction file without writing
* causes a 0-byte write so that the file can return
* state information
*/
ssize_t rv = nfsctl_transaction_write(file, buf, 0, pos);
if (rv < 0)
return rv;
}
return simple_transaction_read(file, buf, size, pos);
}
static const struct file_operations transaction_ops = {
.write = nfsctl_transaction_write,
.read = nfsctl_transaction_read,
.release = simple_transaction_release,
.llseek = default_llseek,
};
static int exports_net_open(struct net *net, struct file *file)
{
int err;
struct seq_file *seq;
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
err = seq_open(file, &nfs_exports_op);
if (err)
return err;
seq = file->private_data;
seq->private = nn->svc_export_cache;
return 0;
}
static int exports_proc_open(struct inode *inode, struct file *file)
{
return exports_net_open(current->nsproxy->net_ns, file);
}
static const struct file_operations exports_proc_operations = {
.open = exports_proc_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
static int exports_nfsd_open(struct inode *inode, struct file *file)
{
return exports_net_open(inode->i_sb->s_fs_info, file);
}
static const struct file_operations exports_nfsd_operations = {
.open = exports_nfsd_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
static int export_features_show(struct seq_file *m, void *v)
{
seq_printf(m, "0x%x 0x%x\n", NFSEXP_ALLFLAGS, NFSEXP_SECINFO_FLAGS);
return 0;
}
static int export_features_open(struct inode *inode, struct file *file)
{
return single_open(file, export_features_show, NULL);
}
static const struct file_operations export_features_operations = {
.open = export_features_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
#if defined(CONFIG_SUNRPC_GSS) || defined(CONFIG_SUNRPC_GSS_MODULE)
static int supported_enctypes_show(struct seq_file *m, void *v)
{
seq_printf(m, KRB5_SUPPORTED_ENCTYPES);
return 0;
}
static int supported_enctypes_open(struct inode *inode, struct file *file)
{
return single_open(file, supported_enctypes_show, NULL);
}
static const struct file_operations supported_enctypes_ops = {
.open = supported_enctypes_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
#endif /* CONFIG_SUNRPC_GSS or CONFIG_SUNRPC_GSS_MODULE */
static const struct file_operations pool_stats_operations = {
.open = nfsd_pool_stats_open,
.read = seq_read,
.llseek = seq_lseek,
.release = nfsd_pool_stats_release,
};
static const struct file_operations reply_cache_stats_operations = {
.open = nfsd_reply_cache_stats_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
/*----------------------------------------------------------------------------*/
/*
* payload - write methods
*/
static inline struct net *netns(struct file *file)
{
return file_inode(file)->i_sb->s_fs_info;
}
/**
* write_unlock_ip - Release all locks used by a client
*
* Experimental.
*
* Input:
* buf: '\n'-terminated C string containing a
* presentation format IP address
* size: length of C string in @buf
* Output:
* On success: returns zero if all specified locks were released;
* returns one if one or more locks were not released
* On error: return code is negative errno value
*/
static ssize_t write_unlock_ip(struct file *file, char *buf, size_t size)
{
struct sockaddr_storage address;
struct sockaddr *sap = (struct sockaddr *)&address;
size_t salen = sizeof(address);
char *fo_path;
struct net *net = netns(file);
/* sanity check */
if (size == 0)
return -EINVAL;
if (buf[size-1] != '\n')
return -EINVAL;
fo_path = buf;
if (qword_get(&buf, fo_path, size) < 0)
return -EINVAL;
if (rpc_pton(net, fo_path, size, sap, salen) == 0)
return -EINVAL;
return nlmsvc_unlock_all_by_ip(sap);
}
/**
* write_unlock_fs - Release all locks on a local file system
*
* Experimental.
*
* Input:
* buf: '\n'-terminated C string containing the
* absolute pathname of a local file system
* size: length of C string in @buf
* Output:
* On success: returns zero if all specified locks were released;
* returns one if one or more locks were not released
* On error: return code is negative errno value
*/
static ssize_t write_unlock_fs(struct file *file, char *buf, size_t size)
{
struct path path;
char *fo_path;
int error;
/* sanity check */
if (size == 0)
return -EINVAL;
if (buf[size-1] != '\n')
return -EINVAL;
fo_path = buf;
if (qword_get(&buf, fo_path, size) < 0)
return -EINVAL;
error = kern_path(fo_path, 0, &path);
if (error)
return error;
/*
* XXX: Needs better sanity checking. Otherwise we could end up
* releasing locks on the wrong file system.
*
* For example:
* 1. Does the path refer to a directory?
* 2. Is that directory a mount point, or
* 3. Is that directory the root of an exported file system?
*/
error = nlmsvc_unlock_all_by_sb(path.dentry->d_sb);
path_put(&path);
return error;
}
/**
* write_filehandle - Get a variable-length NFS file handle by path
*
* On input, the buffer contains a '\n'-terminated C string comprised of
* three alphanumeric words separated by whitespace. The string may
* contain escape sequences.
*
* Input:
* buf:
* domain: client domain name
* path: export pathname
* maxsize: numeric maximum size of
* @buf
* size: length of C string in @buf
* Output:
* On success: passed-in buffer filled with '\n'-terminated C
* string containing a ASCII hex text version
* of the NFS file handle;
* return code is the size in bytes of the string
* On error: return code is negative errno value
*/
static ssize_t write_filehandle(struct file *file, char *buf, size_t size)
{
char *dname, *path;
int uninitialized_var(maxsize);
char *mesg = buf;
int len;
struct auth_domain *dom;
struct knfsd_fh fh;
if (size == 0)
return -EINVAL;
if (buf[size-1] != '\n')
return -EINVAL;
buf[size-1] = 0;
dname = mesg;
len = qword_get(&mesg, dname, size);
if (len <= 0)
return -EINVAL;
path = dname+len+1;
len = qword_get(&mesg, path, size);
if (len <= 0)
return -EINVAL;
len = get_int(&mesg, &maxsize);
if (len)
return len;
if (maxsize < NFS_FHSIZE)
return -EINVAL;
maxsize = min(maxsize, NFS3_FHSIZE);
if (qword_get(&mesg, mesg, size)>0)
return -EINVAL;
/* we have all the words, they are in buf.. */
dom = unix_domain_find(dname);
if (!dom)
return -ENOMEM;
len = exp_rootfh(netns(file), dom, path, &fh, maxsize);
auth_domain_put(dom);
if (len)
return len;
mesg = buf;
len = SIMPLE_TRANSACTION_LIMIT;
qword_addhex(&mesg, &len, (char*)&fh.fh_base, fh.fh_size);
mesg[-1] = '\n';
return mesg - buf;
}
/**
* write_threads - Start NFSD, or report the current number of running threads
*
* Input:
* buf: ignored
* size: zero
* Output:
* On success: passed-in buffer filled with '\n'-terminated C
* string numeric value representing the number of
* running NFSD threads;
* return code is the size in bytes of the string
* On error: return code is zero
*
* OR
*
* Input:
* buf: C string containing an unsigned
* integer value representing the
* number of NFSD threads to start
* size: non-zero length of C string in @buf
* Output:
* On success: NFS service is started;
* passed-in buffer filled with '\n'-terminated C
* string numeric value representing the number of
* running NFSD threads;
* return code is the size in bytes of the string
* On error: return code is zero or a negative errno value
*/
static ssize_t write_threads(struct file *file, char *buf, size_t size)
{
char *mesg = buf;
int rv;
struct net *net = netns(file);
if (size > 0) {
int newthreads;
rv = get_int(&mesg, &newthreads);
if (rv)
return rv;
if (newthreads < 0)
return -EINVAL;
rv = nfsd_svc(newthreads, net);
if (rv < 0)
return rv;
} else
rv = nfsd_nrthreads(net);
return scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, "%d\n", rv);
}
/**
* write_pool_threads - Set or report the current number of threads per pool
*
* Input:
* buf: ignored
* size: zero
*
* OR
*
* Input:
* buf: C string containing whitespace-
* separated unsigned integer values
* representing the number of NFSD
* threads to start in each pool
* size: non-zero length of C string in @buf
* Output:
* On success: passed-in buffer filled with '\n'-terminated C
* string containing integer values representing the
* number of NFSD threads in each pool;
* return code is the size in bytes of the string
* On error: return code is zero or a negative errno value
*/
static ssize_t write_pool_threads(struct file *file, char *buf, size_t size)
{
/* if size > 0, look for an array of number of threads per node
* and apply them then write out number of threads per node as reply
*/
char *mesg = buf;
int i;
int rv;
int len;
int npools;
int *nthreads;
struct net *net = netns(file);
mutex_lock(&nfsd_mutex);
npools = nfsd_nrpools(net);
if (npools == 0) {
/*
* NFS is shut down. The admin can start it by
* writing to the threads file but NOT the pool_threads
* file, sorry. Report zero threads.
*/
mutex_unlock(&nfsd_mutex);
strcpy(buf, "0\n");
return strlen(buf);
}
nthreads = kcalloc(npools, sizeof(int), GFP_KERNEL);
rv = -ENOMEM;
if (nthreads == NULL)
goto out_free;
if (size > 0) {
for (i = 0; i < npools; i++) {
rv = get_int(&mesg, &nthreads[i]);
if (rv == -ENOENT)
break; /* fewer numbers than pools */
if (rv)
goto out_free; /* syntax error */
rv = -EINVAL;
if (nthreads[i] < 0)
goto out_free;
}
rv = nfsd_set_nrthreads(i, nthreads, net);
if (rv)
goto out_free;
}
rv = nfsd_get_nrthreads(npools, nthreads, net);
if (rv)
goto out_free;
mesg = buf;
size = SIMPLE_TRANSACTION_LIMIT;
for (i = 0; i < npools && size > 0; i++) {
snprintf(mesg, size, "%d%c", nthreads[i], (i == npools-1 ? '\n' : ' '));
len = strlen(mesg);
size -= len;
mesg += len;
}
rv = mesg - buf;
out_free:
kfree(nthreads);
mutex_unlock(&nfsd_mutex);
return rv;
}
static ssize_t
nfsd_print_version_support(char *buf, int remaining, const char *sep,
unsigned vers, int minor)
{
const char *format = minor < 0 ? "%s%c%u" : "%s%c%u.%u";
bool supported = !!nfsd_vers(vers, NFSD_TEST);
if (vers == 4 && minor >= 0 &&
!nfsd_minorversion(minor, NFSD_TEST))
supported = false;
if (minor == 0 && supported)
/*
* special case for backward compatability.
* +4.0 is never reported, it is implied by
* +4, unless -4.0 is present.
*/
return 0;
return snprintf(buf, remaining, format, sep,
supported ? '+' : '-', vers, minor);
}
static ssize_t __write_versions(struct file *file, char *buf, size_t size)
{
char *mesg = buf;
char *vers, *minorp, sign;
int len, num, remaining;
ssize_t tlen = 0;
char *sep;
struct nfsd_net *nn = net_generic(netns(file), nfsd_net_id);
if (size>0) {
if (nn->nfsd_serv)
/* Cannot change versions without updating
* nn->nfsd_serv->sv_xdrsize, and reallocing
* rq_argp and rq_resp
*/
return -EBUSY;
if (buf[size-1] != '\n')
return -EINVAL;
buf[size-1] = 0;
vers = mesg;
len = qword_get(&mesg, vers, size);
if (len <= 0) return -EINVAL;
do {
enum vers_op cmd;
unsigned minor;
sign = *vers;
if (sign == '+' || sign == '-')
num = simple_strtol((vers+1), &minorp, 0);
else
num = simple_strtol(vers, &minorp, 0);
if (*minorp == '.') {
if (num != 4)
return -EINVAL;
if (kstrtouint(minorp+1, 0, &minor) < 0)
return -EINVAL;
}
cmd = sign == '-' ? NFSD_CLEAR : NFSD_SET;
switch(num) {
case 2:
case 3:
nfsd_vers(num, cmd);
break;
case 4:
if (*minorp == '.') {
if (nfsd_minorversion(minor, cmd) < 0)
return -EINVAL;
} else if ((cmd == NFSD_SET) != nfsd_vers(num, NFSD_TEST)) {
/*
* Either we have +4 and no minors are enabled,
* or we have -4 and at least one minor is enabled.
* In either case, propagate 'cmd' to all minors.
*/
minor = 0;
while (nfsd_minorversion(minor, cmd) >= 0)
minor++;
}
break;
default:
return -EINVAL;
}
vers += len + 1;
} while ((len = qword_get(&mesg, vers, size)) > 0);
/* If all get turned off, turn them back on, as
* having no versions is BAD
*/
nfsd_reset_versions();
}
/* Now write current state into reply buffer */
len = 0;
sep = "";
remaining = SIMPLE_TRANSACTION_LIMIT;
for (num=2 ; num <= 4 ; num++) {
int minor;
if (!nfsd_vers(num, NFSD_AVAIL))
continue;
minor = -1;
do {
len = nfsd_print_version_support(buf, remaining,
sep, num, minor);
if (len >= remaining)
goto out;
remaining -= len;
buf += len;
tlen += len;
minor++;
if (len)
sep = " ";
} while (num == 4 && minor <= NFSD_SUPPORTED_MINOR_VERSION);
}
out:
len = snprintf(buf, remaining, "\n");
if (len >= remaining)
return -EINVAL;
return tlen + len;
}
/**
* write_versions - Set or report the available NFS protocol versions
*
* Input:
* buf: ignored
* size: zero
* Output:
* On success: passed-in buffer filled with '\n'-terminated C
* string containing positive or negative integer
* values representing the current status of each
* protocol version;
* return code is the size in bytes of the string
* On error: return code is zero or a negative errno value
*
* OR
*
* Input:
* buf: C string containing whitespace-
* separated positive or negative
* integer values representing NFS
* protocol versions to enable ("+n")
* or disable ("-n")
* size: non-zero length of C string in @buf
* Output:
* On success: status of zero or more protocol versions has
* been updated; passed-in buffer filled with
* '\n'-terminated C string containing positive
* or negative integer values representing the
* current status of each protocol version;
* return code is the size in bytes of the string
* On error: return code is zero or a negative errno value
*/
static ssize_t write_versions(struct file *file, char *buf, size_t size)
{
ssize_t rv;
mutex_lock(&nfsd_mutex);
rv = __write_versions(file, buf, size);
mutex_unlock(&nfsd_mutex);
return rv;
}
/*
* Zero-length write. Return a list of NFSD's current listener
* transports.
*/
static ssize_t __write_ports_names(char *buf, struct net *net)
{
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
if (nn->nfsd_serv == NULL)
return 0;
return svc_xprt_names(nn->nfsd_serv, buf, SIMPLE_TRANSACTION_LIMIT);
}
/*
* A single 'fd' number was written, in which case it must be for
* a socket of a supported family/protocol, and we use it as an
* nfsd listener.
*/
static ssize_t __write_ports_addfd(char *buf, struct net *net)
{
char *mesg = buf;
int fd, err;
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
err = get_int(&mesg, &fd);
if (err != 0 || fd < 0)
return -EINVAL;
if (svc_alien_sock(net, fd)) {
printk(KERN_ERR "%s: socket net is different to NFSd's one\n", __func__);
return -EINVAL;
}
err = nfsd_create_serv(net);
if (err != 0)
return err;
err = svc_addsock(nn->nfsd_serv, fd, buf, SIMPLE_TRANSACTION_LIMIT);
if (err < 0) {
nfsd_destroy(net);
return err;
}
/* Decrease the count, but don't shut down the service */
nn->nfsd_serv->sv_nrthreads--;
return err;
}
/*
* A transport listener is added by writing it's transport name and
* a port number.
*/
static ssize_t __write_ports_addxprt(char *buf, struct net *net)
{
char transport[16];
struct svc_xprt *xprt;
int port, err;
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
if (sscanf(buf, "%15s %5u", transport, &port) != 2)
return -EINVAL;
if (port < 1 || port > USHRT_MAX)
return -EINVAL;
err = nfsd_create_serv(net);
if (err != 0)
return err;
err = svc_create_xprt(nn->nfsd_serv, transport, net,
PF_INET, port, SVC_SOCK_ANONYMOUS);
if (err < 0)
goto out_err;
err = svc_create_xprt(nn->nfsd_serv, transport, net,
PF_INET6, port, SVC_SOCK_ANONYMOUS);
if (err < 0 && err != -EAFNOSUPPORT)
goto out_close;
/* Decrease the count, but don't shut down the service */
nn->nfsd_serv->sv_nrthreads--;
return 0;
out_close:
xprt = svc_find_xprt(nn->nfsd_serv, transport, net, PF_INET, port);
if (xprt != NULL) {
svc_close_xprt(xprt);
svc_xprt_put(xprt);
}
out_err:
nfsd_destroy(net);
return err;
}
static ssize_t __write_ports(struct file *file, char *buf, size_t size,
struct net *net)
{
if (size == 0)
return __write_ports_names(buf, net);
if (isdigit(buf[0]))
return __write_ports_addfd(buf, net);
if (isalpha(buf[0]))
return __write_ports_addxprt(buf, net);
return -EINVAL;
}
/**
* write_ports - Pass a socket file descriptor or transport name to listen on
*
* Input:
* buf: ignored
* size: zero
* Output:
* On success: passed-in buffer filled with a '\n'-terminated C
* string containing a whitespace-separated list of
* named NFSD listeners;
* return code is the size in bytes of the string
* On error: return code is zero or a negative errno value
*
* OR
*
* Input:
* buf: C string containing an unsigned
* integer value representing a bound
* but unconnected socket that is to be
* used as an NFSD listener; listen(3)
* must be called for a SOCK_STREAM
* socket, otherwise it is ignored
* size: non-zero length of C string in @buf
* Output:
* On success: NFS service is started;
* passed-in buffer filled with a '\n'-terminated C
* string containing a unique alphanumeric name of
* the listener;
* return code is the size in bytes of the string
* On error: return code is a negative errno value
*
* OR
*
* Input:
* buf: C string containing a transport
* name and an unsigned integer value
* representing the port to listen on,
* separated by whitespace
* size: non-zero length of C string in @buf
* Output:
* On success: returns zero; NFS service is started
* On error: return code is a negative errno value
*/
static ssize_t write_ports(struct file *file, char *buf, size_t size)
{
ssize_t rv;
mutex_lock(&nfsd_mutex);
rv = __write_ports(file, buf, size, netns(file));
mutex_unlock(&nfsd_mutex);
return rv;
}
int nfsd_max_blksize;
/**
* write_maxblksize - Set or report the current NFS blksize
*
* Input:
* buf: ignored
* size: zero
*
* OR
*
* Input:
* buf: C string containing an unsigned
* integer value representing the new
* NFS blksize
* size: non-zero length of C string in @buf
* Output:
* On success: passed-in buffer filled with '\n'-terminated C string
* containing numeric value of the current NFS blksize
* setting;
* return code is the size in bytes of the string
* On error: return code is zero or a negative errno value
*/
static ssize_t write_maxblksize(struct file *file, char *buf, size_t size)
{
char *mesg = buf;
struct nfsd_net *nn = net_generic(netns(file), nfsd_net_id);
if (size > 0) {
int bsize;
int rv = get_int(&mesg, &bsize);
if (rv)
return rv;
/* force bsize into allowed range and
* required alignment.
*/
bsize = max_t(int, bsize, 1024);
bsize = min_t(int, bsize, NFSSVC_MAXBLKSIZE);
bsize &= ~(1024-1);
mutex_lock(&nfsd_mutex);
if (nn->nfsd_serv) {
mutex_unlock(&nfsd_mutex);
return -EBUSY;
}
nfsd_max_blksize = bsize;
mutex_unlock(&nfsd_mutex);
}
return scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, "%d\n",
nfsd_max_blksize);
}
/**
* write_maxconn - Set or report the current max number of connections
*
* Input:
* buf: ignored
* size: zero
* OR
*
* Input:
* buf: C string containing an unsigned
* integer value representing the new
* number of max connections
* size: non-zero length of C string in @buf
* Output:
* On success: passed-in buffer filled with '\n'-terminated C string
* containing numeric value of max_connections setting
* for this net namespace;
* return code is the size in bytes of the string
* On error: return code is zero or a negative errno value
*/
static ssize_t write_maxconn(struct file *file, char *buf, size_t size)
{
char *mesg = buf;
struct nfsd_net *nn = net_generic(netns(file), nfsd_net_id);
unsigned int maxconn = nn->max_connections;
if (size > 0) {
int rv = get_uint(&mesg, &maxconn);
if (rv)
return rv;
nn->max_connections = maxconn;
}
return scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, "%u\n", maxconn);
}
#ifdef CONFIG_NFSD_V4
static ssize_t __nfsd4_write_time(struct file *file, char *buf, size_t size,
time_t *time, struct nfsd_net *nn)
{
char *mesg = buf;
int rv, i;
if (size > 0) {
if (nn->nfsd_serv)
return -EBUSY;
rv = get_int(&mesg, &i);
if (rv)
return rv;
/*
* Some sanity checking. We don't have a reason for
* these particular numbers, but problems with the
* extremes are:
* - Too short: the briefest network outage may
* cause clients to lose all their locks. Also,
* the frequent polling may be wasteful.
* - Too long: do you really want reboot recovery
* to take more than an hour? Or to make other
* clients wait an hour before being able to
* revoke a dead client's locks?
*/
if (i < 10 || i > 3600)
return -EINVAL;
*time = i;
}
return scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, "%ld\n", *time);
}
static ssize_t nfsd4_write_time(struct file *file, char *buf, size_t size,
time_t *time, struct nfsd_net *nn)
{
ssize_t rv;
mutex_lock(&nfsd_mutex);
rv = __nfsd4_write_time(file, buf, size, time, nn);
mutex_unlock(&nfsd_mutex);
return rv;
}
/**
* write_leasetime - Set or report the current NFSv4 lease time
*
* Input:
* buf: ignored
* size: zero
*
* OR
*
* Input:
* buf: C string containing an unsigned
* integer value representing the new
* NFSv4 lease expiry time
* size: non-zero length of C string in @buf
* Output:
* On success: passed-in buffer filled with '\n'-terminated C
* string containing unsigned integer value of the
* current lease expiry time;
* return code is the size in bytes of the string
* On error: return code is zero or a negative errno value
*/
static ssize_t write_leasetime(struct file *file, char *buf, size_t size)
{
struct nfsd_net *nn = net_generic(netns(file), nfsd_net_id);
return nfsd4_write_time(file, buf, size, &nn->nfsd4_lease, nn);
}
/**
* write_gracetime - Set or report current NFSv4 grace period time
*
* As above, but sets the time of the NFSv4 grace period.
*
* Note this should never be set to less than the *previous*
* lease-period time, but we don't try to enforce this. (In the common
* case (a new boot), we don't know what the previous lease time was
* anyway.)
*/
static ssize_t write_gracetime(struct file *file, char *buf, size_t size)
{
struct nfsd_net *nn = net_generic(netns(file), nfsd_net_id);
return nfsd4_write_time(file, buf, size, &nn->nfsd4_grace, nn);
}
static ssize_t __write_recoverydir(struct file *file, char *buf, size_t size,
struct nfsd_net *nn)
{
char *mesg = buf;
char *recdir;
int len, status;
if (size > 0) {
if (nn->nfsd_serv)
return -EBUSY;
if (size > PATH_MAX || buf[size-1] != '\n')
return -EINVAL;
buf[size-1] = 0;
recdir = mesg;
len = qword_get(&mesg, recdir, size);
if (len <= 0)
return -EINVAL;
status = nfs4_reset_recoverydir(recdir);
if (status)
return status;
}
return scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, "%s\n",
nfs4_recoverydir());
}
/**
* write_recoverydir - Set or report the pathname of the recovery directory
*
* Input:
* buf: ignored
* size: zero
*
* OR
*
* Input:
* buf: C string containing the pathname
* of the directory on a local file
* system containing permanent NFSv4
* recovery data
* size: non-zero length of C string in @buf
* Output:
* On success: passed-in buffer filled with '\n'-terminated C string
* containing the current recovery pathname setting;
* return code is the size in bytes of the string
* On error: return code is zero or a negative errno value
*/
static ssize_t write_recoverydir(struct file *file, char *buf, size_t size)
{
ssize_t rv;
struct nfsd_net *nn = net_generic(netns(file), nfsd_net_id);
mutex_lock(&nfsd_mutex);
rv = __write_recoverydir(file, buf, size, nn);
mutex_unlock(&nfsd_mutex);
return rv;
}
/**
* write_v4_end_grace - release grace period for nfsd's v4.x lock manager
*
* Input:
* buf: ignored
* size: zero
* OR
*
* Input:
* buf: any value
* size: non-zero length of C string in @buf
* Output:
* passed-in buffer filled with "Y" or "N" with a newline
* and NULL-terminated C string. This indicates whether
* the grace period has ended in the current net
* namespace. Return code is the size in bytes of the
* string. Writing a string that starts with 'Y', 'y', or
* '1' to the file will end the grace period for nfsd's v4
* lock manager.
*/
static ssize_t write_v4_end_grace(struct file *file, char *buf, size_t size)
{
struct nfsd_net *nn = net_generic(netns(file), nfsd_net_id);
if (size > 0) {
switch(buf[0]) {
case 'Y':
case 'y':
case '1':
nfsd4_end_grace(nn);
break;
default:
return -EINVAL;
}
}
return scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, "%c\n",
nn->grace_ended ? 'Y' : 'N');
}
#endif
/*----------------------------------------------------------------------------*/
/*
* populating the filesystem.
*/
static int nfsd_fill_super(struct super_block * sb, void * data, int silent)
{
static const struct tree_descr nfsd_files[] = {
[NFSD_List] = {"exports", &exports_nfsd_operations, S_IRUGO},
[NFSD_Export_features] = {"export_features",
&export_features_operations, S_IRUGO},
[NFSD_FO_UnlockIP] = {"unlock_ip",
&transaction_ops, S_IWUSR|S_IRUSR},
[NFSD_FO_UnlockFS] = {"unlock_filesystem",
&transaction_ops, S_IWUSR|S_IRUSR},
[NFSD_Fh] = {"filehandle", &transaction_ops, S_IWUSR|S_IRUSR},
[NFSD_Threads] = {"threads", &transaction_ops, S_IWUSR|S_IRUSR},
[NFSD_Pool_Threads] = {"pool_threads", &transaction_ops, S_IWUSR|S_IRUSR},
[NFSD_Pool_Stats] = {"pool_stats", &pool_stats_operations, S_IRUGO},
[NFSD_Reply_Cache_Stats] = {"reply_cache_stats", &reply_cache_stats_operations, S_IRUGO},
[NFSD_Versions] = {"versions", &transaction_ops, S_IWUSR|S_IRUSR},
[NFSD_Ports] = {"portlist", &transaction_ops, S_IWUSR|S_IRUGO},
[NFSD_MaxBlkSize] = {"max_block_size", &transaction_ops, S_IWUSR|S_IRUGO},
[NFSD_MaxConnections] = {"max_connections", &transaction_ops, S_IWUSR|S_IRUGO},
#if defined(CONFIG_SUNRPC_GSS) || defined(CONFIG_SUNRPC_GSS_MODULE)
[NFSD_SupportedEnctypes] = {"supported_krb5_enctypes", &supported_enctypes_ops, S_IRUGO},
#endif /* CONFIG_SUNRPC_GSS or CONFIG_SUNRPC_GSS_MODULE */
#ifdef CONFIG_NFSD_V4
[NFSD_Leasetime] = {"nfsv4leasetime", &transaction_ops, S_IWUSR|S_IRUSR},
[NFSD_Gracetime] = {"nfsv4gracetime", &transaction_ops, S_IWUSR|S_IRUSR},
[NFSD_RecoveryDir] = {"nfsv4recoverydir", &transaction_ops, S_IWUSR|S_IRUSR},
[NFSD_V4EndGrace] = {"v4_end_grace", &transaction_ops, S_IWUSR|S_IRUGO},
#endif
/* last one */ {""}
};
get_net(sb->s_fs_info);
return simple_fill_super(sb, 0x6e667364, nfsd_files);
}
static struct dentry *nfsd_mount(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data)
{
struct net *net = current->nsproxy->net_ns;
return mount_ns(fs_type, flags, data, net, net->user_ns, nfsd_fill_super);
}
static void nfsd_umount(struct super_block *sb)
{
struct net *net = sb->s_fs_info;
kill_litter_super(sb);
put_net(net);
}
static struct file_system_type nfsd_fs_type = {
.owner = THIS_MODULE,
.name = "nfsd",
.mount = nfsd_mount,
.kill_sb = nfsd_umount,
};
MODULE_ALIAS_FS("nfsd");
#ifdef CONFIG_PROC_FS
static int create_proc_exports_entry(void)
{
struct proc_dir_entry *entry;
entry = proc_mkdir("fs/nfs", NULL);
if (!entry)
return -ENOMEM;
entry = proc_create("exports", 0, entry,
&exports_proc_operations);
if (!entry) {
remove_proc_entry("fs/nfs", NULL);
return -ENOMEM;
}
return 0;
}
#else /* CONFIG_PROC_FS */
static int create_proc_exports_entry(void)
{
return 0;
}
#endif
unsigned int nfsd_net_id;
static __net_init int nfsd_init_net(struct net *net)
{
int retval;
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
retval = nfsd_export_init(net);
if (retval)
goto out_export_error;
retval = nfsd_idmap_init(net);
if (retval)
goto out_idmap_error;
nn->nfsd4_lease = 90; /* default lease time */
nn->nfsd4_grace = 90;
nn->clverifier_counter = prandom_u32();
nn->clientid_counter = prandom_u32();
atomic_set(&nn->ntf_refcnt, 0);
init_waitqueue_head(&nn->ntf_wq);
return 0;
out_idmap_error:
nfsd_export_shutdown(net);
out_export_error:
return retval;
}
static __net_exit void nfsd_exit_net(struct net *net)
{
nfsd_idmap_shutdown(net);
nfsd_export_shutdown(net);
}
static struct pernet_operations nfsd_net_ops = {
.init = nfsd_init_net,
.exit = nfsd_exit_net,
.id = &nfsd_net_id,
.size = sizeof(struct nfsd_net),
};
static int __init init_nfsd(void)
{
int retval;
printk(KERN_INFO "Installing knfsd (copyright (C) 1996 okir@monad.swb.de).\n");
retval = register_pernet_subsys(&nfsd_net_ops);
if (retval < 0)
return retval;
retval = register_cld_notifier();
if (retval)
goto out_unregister_pernet;
retval = nfsd4_init_slabs();
if (retval)
goto out_unregister_notifier;
retval = nfsd4_init_pnfs();
if (retval)
goto out_free_slabs;
retval = nfsd_fault_inject_init(); /* nfsd fault injection controls */
if (retval)
goto out_exit_pnfs;
nfsd_stat_init(); /* Statistics */
retval = nfsd_reply_cache_init();
if (retval)
goto out_free_stat;
nfsd_lockd_init(); /* lockd->nfsd callbacks */
retval = create_proc_exports_entry();
if (retval)
goto out_free_lockd;
retval = register_filesystem(&nfsd_fs_type);
if (retval)
goto out_free_all;
return 0;
out_free_all:
remove_proc_entry("fs/nfs/exports", NULL);
remove_proc_entry("fs/nfs", NULL);
out_free_lockd:
nfsd_lockd_shutdown();
nfsd_reply_cache_shutdown();
out_free_stat:
nfsd_stat_shutdown();
nfsd_fault_inject_cleanup();
out_exit_pnfs:
nfsd4_exit_pnfs();
out_free_slabs:
nfsd4_free_slabs();
out_unregister_notifier:
unregister_cld_notifier();
out_unregister_pernet:
unregister_pernet_subsys(&nfsd_net_ops);
return retval;
}
static void __exit exit_nfsd(void)
{
nfsd_reply_cache_shutdown();
remove_proc_entry("fs/nfs/exports", NULL);
remove_proc_entry("fs/nfs", NULL);
nfsd_stat_shutdown();
nfsd_lockd_shutdown();
nfsd4_free_slabs();
nfsd4_exit_pnfs();
nfsd_fault_inject_cleanup();
unregister_filesystem(&nfsd_fs_type);
unregister_cld_notifier();
unregister_pernet_subsys(&nfsd_net_ops);
}
MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
MODULE_LICENSE("GPL");
module_init(init_nfsd)
module_exit(exit_nfsd)