linux/fs/nfsd/nfsproc.c

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/*
* nfsproc2.c Process version 2 NFS requests.
* linux/fs/nfsd/nfs2proc.c
*
* Process version 2 NFS requests.
*
* Copyright (C) 1995-1997 Olaf Kirch <okir@monad.swb.de>
*/
#include <linux/linkage.h>
#include <linux/time.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/stat.h>
#include <linux/fcntl.h>
#include <linux/net.h>
#include <linux/in.h>
#include <linux/namei.h>
#include <linux/unistd.h>
#include <linux/slab.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/svc.h>
#include <linux/nfsd/nfsd.h>
#include <linux/nfsd/cache.h>
#include <linux/nfsd/xdr.h>
typedef struct svc_rqst svc_rqst;
typedef struct svc_buf svc_buf;
#define NFSDDBG_FACILITY NFSDDBG_PROC
static __be32
nfsd_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
{
return nfs_ok;
}
static __be32
nfsd_return_attrs(__be32 err, struct nfsd_attrstat *resp)
{
if (err) return err;
return nfserrno(vfs_getattr(resp->fh.fh_export->ex_path.mnt,
resp->fh.fh_dentry,
&resp->stat));
}
static __be32
nfsd_return_dirop(__be32 err, struct nfsd_diropres *resp)
{
if (err) return err;
return nfserrno(vfs_getattr(resp->fh.fh_export->ex_path.mnt,
resp->fh.fh_dentry,
&resp->stat));
}
/*
* Get a file's attributes
* N.B. After this call resp->fh needs an fh_put
*/
static __be32
nfsd_proc_getattr(struct svc_rqst *rqstp, struct nfsd_fhandle *argp,
struct nfsd_attrstat *resp)
{
__be32 nfserr;
dprintk("nfsd: GETATTR %s\n", SVCFH_fmt(&argp->fh));
fh_copy(&resp->fh, &argp->fh);
nfserr = fh_verify(rqstp, &resp->fh, 0,
NFSD_MAY_NOP | NFSD_MAY_BYPASS_GSS_ON_ROOT);
return nfsd_return_attrs(nfserr, resp);
}
/*
* Set a file's attributes
* N.B. After this call resp->fh needs an fh_put
*/
static __be32
nfsd_proc_setattr(struct svc_rqst *rqstp, struct nfsd_sattrargs *argp,
struct nfsd_attrstat *resp)
{
__be32 nfserr;
dprintk("nfsd: SETATTR %s, valid=%x, size=%ld\n",
SVCFH_fmt(&argp->fh),
argp->attrs.ia_valid, (long) argp->attrs.ia_size);
fh_copy(&resp->fh, &argp->fh);
nfserr = nfsd_setattr(rqstp, &resp->fh, &argp->attrs,0, (time_t)0);
return nfsd_return_attrs(nfserr, resp);
}
/*
* Look up a path name component
* Note: the dentry in the resp->fh may be negative if the file
* doesn't exist yet.
* N.B. After this call resp->fh needs an fh_put
*/
static __be32
nfsd_proc_lookup(struct svc_rqst *rqstp, struct nfsd_diropargs *argp,
struct nfsd_diropres *resp)
{
__be32 nfserr;
dprintk("nfsd: LOOKUP %s %.*s\n",
SVCFH_fmt(&argp->fh), argp->len, argp->name);
fh_init(&resp->fh, NFS_FHSIZE);
nfserr = nfsd_lookup(rqstp, &argp->fh, argp->name, argp->len,
&resp->fh);
fh_put(&argp->fh);
return nfsd_return_dirop(nfserr, resp);
}
/*
* Read a symlink.
*/
static __be32
nfsd_proc_readlink(struct svc_rqst *rqstp, struct nfsd_readlinkargs *argp,
struct nfsd_readlinkres *resp)
{
__be32 nfserr;
dprintk("nfsd: READLINK %s\n", SVCFH_fmt(&argp->fh));
/* Read the symlink. */
resp->len = NFS_MAXPATHLEN;
nfserr = nfsd_readlink(rqstp, &argp->fh, argp->buffer, &resp->len);
fh_put(&argp->fh);
return nfserr;
}
/*
* Read a portion of a file.
* N.B. After this call resp->fh needs an fh_put
*/
static __be32
nfsd_proc_read(struct svc_rqst *rqstp, struct nfsd_readargs *argp,
struct nfsd_readres *resp)
{
__be32 nfserr;
dprintk("nfsd: READ %s %d bytes at %d\n",
SVCFH_fmt(&argp->fh),
argp->count, argp->offset);
/* Obtain buffer pointer for payload. 19 is 1 word for
* status, 17 words for fattr, and 1 word for the byte count.
*/
if (NFSSVC_MAXBLKSIZE_V2 < argp->count) {
char buf[RPC_MAX_ADDRBUFLEN];
printk(KERN_NOTICE
"oversized read request from %s (%d bytes)\n",
svc_print_addr(rqstp, buf, sizeof(buf)),
argp->count);
argp->count = NFSSVC_MAXBLKSIZE_V2;
}
RPC: add wrapper for svc_reserve to account for checksum When the kernel calls svc_reserve to downsize the expected size of an RPC reply, it fails to account for the possibility of a checksum at the end of the packet. If a client mounts a NFSv2/3 with sec=krb5i/p, and does I/O then you'll generally see messages similar to this in the server's ring buffer: RPC request reserved 164 but used 208 While I was never able to verify it, I suspect that this problem is also the root cause of some oopses I've seen under these conditions: https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=227726 This is probably also a problem for other sec= types and for NFSv4. The large reserved size for NFSv4 compound packets seems to generally paper over the problem, however. This patch adds a wrapper for svc_reserve that accounts for the possibility of a checksum. It also fixes up the appropriate callers of svc_reserve to call the wrapper. For now, it just uses a hardcoded value that I determined via testing. That value may need to be revised upward as things change, or we may want to eventually add a new auth_op that attempts to calculate this somehow. Unfortunately, there doesn't seem to be a good way to reliably determine the expected checksum length prior to actually calculating it, particularly with schemes like spkm3. Signed-off-by: Jeff Layton <jlayton@redhat.com> Acked-by: Neil Brown <neilb@suse.de> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Acked-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-09 09:34:50 +00:00
svc_reserve_auth(rqstp, (19<<2) + argp->count + 4);
resp->count = argp->count;
nfserr = nfsd_read(rqstp, fh_copy(&resp->fh, &argp->fh), NULL,
argp->offset,
rqstp->rq_vec, argp->vlen,
&resp->count);
if (nfserr) return nfserr;
return nfserrno(vfs_getattr(resp->fh.fh_export->ex_path.mnt,
resp->fh.fh_dentry,
&resp->stat));
}
/*
* Write data to a file
* N.B. After this call resp->fh needs an fh_put
*/
static __be32
nfsd_proc_write(struct svc_rqst *rqstp, struct nfsd_writeargs *argp,
struct nfsd_attrstat *resp)
{
__be32 nfserr;
int stable = 1;
unsigned long cnt = argp->len;
dprintk("nfsd: WRITE %s %d bytes at %d\n",
SVCFH_fmt(&argp->fh),
argp->len, argp->offset);
nfserr = nfsd_write(rqstp, fh_copy(&resp->fh, &argp->fh), NULL,
argp->offset,
rqstp->rq_vec, argp->vlen,
&cnt,
&stable);
return nfsd_return_attrs(nfserr, resp);
}
/*
* CREATE processing is complicated. The keyword here is `overloaded.'
* The parent directory is kept locked between the check for existence
* and the actual create() call in compliance with VFS protocols.
* N.B. After this call _both_ argp->fh and resp->fh need an fh_put
*/
static __be32
nfsd_proc_create(struct svc_rqst *rqstp, struct nfsd_createargs *argp,
struct nfsd_diropres *resp)
{
svc_fh *dirfhp = &argp->fh;
svc_fh *newfhp = &resp->fh;
struct iattr *attr = &argp->attrs;
struct inode *inode;
struct dentry *dchild;
int type, mode;
__be32 nfserr;
dev_t rdev = 0, wanted = new_decode_dev(attr->ia_size);
dprintk("nfsd: CREATE %s %.*s\n",
SVCFH_fmt(dirfhp), argp->len, argp->name);
/* First verify the parent file handle */
nfserr = fh_verify(rqstp, dirfhp, S_IFDIR, NFSD_MAY_EXEC);
if (nfserr)
goto done; /* must fh_put dirfhp even on error */
/* Check for NFSD_MAY_WRITE in nfsd_create if necessary */
nfserr = nfserr_acces;
if (!argp->len)
goto done;
nfserr = nfserr_exist;
if (isdotent(argp->name, argp->len))
goto done;
fh_lock_nested(dirfhp, I_MUTEX_PARENT);
dchild = lookup_one_len(argp->name, dirfhp->fh_dentry, argp->len);
if (IS_ERR(dchild)) {
nfserr = nfserrno(PTR_ERR(dchild));
goto out_unlock;
}
fh_init(newfhp, NFS_FHSIZE);
nfserr = fh_compose(newfhp, dirfhp->fh_export, dchild, dirfhp);
if (!nfserr && !dchild->d_inode)
nfserr = nfserr_noent;
dput(dchild);
if (nfserr) {
if (nfserr != nfserr_noent)
goto out_unlock;
/*
* If the new file handle wasn't verified, we can't tell
* whether the file exists or not. Time to bail ...
*/
nfserr = nfserr_acces;
if (!newfhp->fh_dentry) {
printk(KERN_WARNING
"nfsd_proc_create: file handle not verified\n");
goto out_unlock;
}
}
inode = newfhp->fh_dentry->d_inode;
/* Unfudge the mode bits */
if (attr->ia_valid & ATTR_MODE) {
type = attr->ia_mode & S_IFMT;
mode = attr->ia_mode & ~S_IFMT;
if (!type) {
/* no type, so if target exists, assume same as that,
* else assume a file */
if (inode) {
type = inode->i_mode & S_IFMT;
switch(type) {
case S_IFCHR:
case S_IFBLK:
/* reserve rdev for later checking */
rdev = inode->i_rdev;
attr->ia_valid |= ATTR_SIZE;
/* FALLTHROUGH */
case S_IFIFO:
/* this is probably a permission check..
* at least IRIX implements perm checking on
* echo thing > device-special-file-or-pipe
* by doing a CREATE with type==0
*/
nfserr = nfsd_permission(rqstp,
newfhp->fh_export,
newfhp->fh_dentry,
NFSD_MAY_WRITE|NFSD_MAY_LOCAL_ACCESS);
if (nfserr && nfserr != nfserr_rofs)
goto out_unlock;
}
} else
type = S_IFREG;
}
} else if (inode) {
type = inode->i_mode & S_IFMT;
mode = inode->i_mode & ~S_IFMT;
} else {
type = S_IFREG;
mode = 0; /* ??? */
}
attr->ia_valid |= ATTR_MODE;
attr->ia_mode = mode;
/* Special treatment for non-regular files according to the
* gospel of sun micro
*/
if (type != S_IFREG) {
int is_borc = 0;
if (type != S_IFBLK && type != S_IFCHR) {
rdev = 0;
} else if (type == S_IFCHR && !(attr->ia_valid & ATTR_SIZE)) {
/* If you think you've seen the worst, grok this. */
type = S_IFIFO;
} else {
/* Okay, char or block special */
is_borc = 1;
if (!rdev)
rdev = wanted;
}
/* we've used the SIZE information, so discard it */
attr->ia_valid &= ~ATTR_SIZE;
/* Make sure the type and device matches */
nfserr = nfserr_exist;
if (inode && type != (inode->i_mode & S_IFMT))
goto out_unlock;
}
nfserr = 0;
if (!inode) {
/* File doesn't exist. Create it and set attrs */
nfserr = nfsd_create(rqstp, dirfhp, argp->name, argp->len,
attr, type, rdev, newfhp);
} else if (type == S_IFREG) {
dprintk("nfsd: existing %s, valid=%x, size=%ld\n",
argp->name, attr->ia_valid, (long) attr->ia_size);
/* File already exists. We ignore all attributes except
* size, so that creat() behaves exactly like
* open(..., O_CREAT|O_TRUNC|O_WRONLY).
*/
attr->ia_valid &= ATTR_SIZE;
if (attr->ia_valid)
nfserr = nfsd_setattr(rqstp, newfhp, attr, 0, (time_t)0);
}
out_unlock:
/* We don't really need to unlock, as fh_put does it. */
fh_unlock(dirfhp);
done:
fh_put(dirfhp);
return nfsd_return_dirop(nfserr, resp);
}
static __be32
nfsd_proc_remove(struct svc_rqst *rqstp, struct nfsd_diropargs *argp,
void *resp)
{
__be32 nfserr;
dprintk("nfsd: REMOVE %s %.*s\n", SVCFH_fmt(&argp->fh),
argp->len, argp->name);
/* Unlink. -SIFDIR means file must not be a directory */
nfserr = nfsd_unlink(rqstp, &argp->fh, -S_IFDIR, argp->name, argp->len);
fh_put(&argp->fh);
return nfserr;
}
static __be32
nfsd_proc_rename(struct svc_rqst *rqstp, struct nfsd_renameargs *argp,
void *resp)
{
__be32 nfserr;
dprintk("nfsd: RENAME %s %.*s -> \n",
SVCFH_fmt(&argp->ffh), argp->flen, argp->fname);
dprintk("nfsd: -> %s %.*s\n",
SVCFH_fmt(&argp->tfh), argp->tlen, argp->tname);
nfserr = nfsd_rename(rqstp, &argp->ffh, argp->fname, argp->flen,
&argp->tfh, argp->tname, argp->tlen);
fh_put(&argp->ffh);
fh_put(&argp->tfh);
return nfserr;
}
static __be32
nfsd_proc_link(struct svc_rqst *rqstp, struct nfsd_linkargs *argp,
void *resp)
{
__be32 nfserr;
dprintk("nfsd: LINK %s ->\n",
SVCFH_fmt(&argp->ffh));
dprintk("nfsd: %s %.*s\n",
SVCFH_fmt(&argp->tfh),
argp->tlen,
argp->tname);
nfserr = nfsd_link(rqstp, &argp->tfh, argp->tname, argp->tlen,
&argp->ffh);
fh_put(&argp->ffh);
fh_put(&argp->tfh);
return nfserr;
}
static __be32
nfsd_proc_symlink(struct svc_rqst *rqstp, struct nfsd_symlinkargs *argp,
void *resp)
{
struct svc_fh newfh;
__be32 nfserr;
dprintk("nfsd: SYMLINK %s %.*s -> %.*s\n",
SVCFH_fmt(&argp->ffh), argp->flen, argp->fname,
argp->tlen, argp->tname);
fh_init(&newfh, NFS_FHSIZE);
/*
* Create the link, look up new file and set attrs.
*/
nfserr = nfsd_symlink(rqstp, &argp->ffh, argp->fname, argp->flen,
argp->tname, argp->tlen,
&newfh, &argp->attrs);
fh_put(&argp->ffh);
fh_put(&newfh);
return nfserr;
}
/*
* Make directory. This operation is not idempotent.
* N.B. After this call resp->fh needs an fh_put
*/
static __be32
nfsd_proc_mkdir(struct svc_rqst *rqstp, struct nfsd_createargs *argp,
struct nfsd_diropres *resp)
{
__be32 nfserr;
dprintk("nfsd: MKDIR %s %.*s\n", SVCFH_fmt(&argp->fh), argp->len, argp->name);
if (resp->fh.fh_dentry) {
printk(KERN_WARNING
"nfsd_proc_mkdir: response already verified??\n");
}
argp->attrs.ia_valid &= ~ATTR_SIZE;
fh_init(&resp->fh, NFS_FHSIZE);
nfserr = nfsd_create(rqstp, &argp->fh, argp->name, argp->len,
&argp->attrs, S_IFDIR, 0, &resp->fh);
fh_put(&argp->fh);
return nfsd_return_dirop(nfserr, resp);
}
/*
* Remove a directory
*/
static __be32
nfsd_proc_rmdir(struct svc_rqst *rqstp, struct nfsd_diropargs *argp,
void *resp)
{
__be32 nfserr;
dprintk("nfsd: RMDIR %s %.*s\n", SVCFH_fmt(&argp->fh), argp->len, argp->name);
nfserr = nfsd_unlink(rqstp, &argp->fh, S_IFDIR, argp->name, argp->len);
fh_put(&argp->fh);
return nfserr;
}
/*
* Read a portion of a directory.
*/
static __be32
nfsd_proc_readdir(struct svc_rqst *rqstp, struct nfsd_readdirargs *argp,
struct nfsd_readdirres *resp)
{
int count;
__be32 nfserr;
loff_t offset;
dprintk("nfsd: READDIR %s %d bytes at %d\n",
SVCFH_fmt(&argp->fh),
argp->count, argp->cookie);
/* Shrink to the client read size */
count = (argp->count >> 2) - 2;
/* Make sure we've room for the NULL ptr & eof flag */
count -= 2;
if (count < 0)
count = 0;
resp->buffer = argp->buffer;
resp->offset = NULL;
resp->buflen = count;
resp->common.err = nfs_ok;
/* Read directory and encode entries on the fly */
offset = argp->cookie;
nfserr = nfsd_readdir(rqstp, &argp->fh, &offset,
&resp->common, nfssvc_encode_entry);
resp->count = resp->buffer - argp->buffer;
if (resp->offset)
*resp->offset = htonl(offset);
fh_put(&argp->fh);
return nfserr;
}
/*
* Get file system info
*/
static __be32
nfsd_proc_statfs(struct svc_rqst * rqstp, struct nfsd_fhandle *argp,
struct nfsd_statfsres *resp)
{
__be32 nfserr;
dprintk("nfsd: STATFS %s\n", SVCFH_fmt(&argp->fh));
nfserr = nfsd_statfs(rqstp, &argp->fh, &resp->stats,
NFSD_MAY_BYPASS_GSS_ON_ROOT);
fh_put(&argp->fh);
return nfserr;
}
/*
* NFSv2 Server procedures.
* Only the results of non-idempotent operations are cached.
*/
#define nfsd_proc_none NULL
#define nfssvc_release_none NULL
struct nfsd_void { int dummy; };
#define PROC(name, argt, rest, relt, cache, respsize) \
{ (svc_procfunc) nfsd_proc_##name, \
(kxdrproc_t) nfssvc_decode_##argt, \
(kxdrproc_t) nfssvc_encode_##rest, \
(kxdrproc_t) nfssvc_release_##relt, \
sizeof(struct nfsd_##argt), \
sizeof(struct nfsd_##rest), \
0, \
cache, \
respsize, \
}
#define ST 1 /* status */
#define FH 8 /* filehandle */
#define AT 18 /* attributes */
static struct svc_procedure nfsd_procedures2[18] = {
PROC(null, void, void, none, RC_NOCACHE, ST),
PROC(getattr, fhandle, attrstat, fhandle, RC_NOCACHE, ST+AT),
PROC(setattr, sattrargs, attrstat, fhandle, RC_REPLBUFF, ST+AT),
PROC(none, void, void, none, RC_NOCACHE, ST),
PROC(lookup, diropargs, diropres, fhandle, RC_NOCACHE, ST+FH+AT),
PROC(readlink, readlinkargs, readlinkres, none, RC_NOCACHE, ST+1+NFS_MAXPATHLEN/4),
PROC(read, readargs, readres, fhandle, RC_NOCACHE, ST+AT+1+NFSSVC_MAXBLKSIZE_V2/4),
PROC(none, void, void, none, RC_NOCACHE, ST),
PROC(write, writeargs, attrstat, fhandle, RC_REPLBUFF, ST+AT),
PROC(create, createargs, diropres, fhandle, RC_REPLBUFF, ST+FH+AT),
PROC(remove, diropargs, void, none, RC_REPLSTAT, ST),
PROC(rename, renameargs, void, none, RC_REPLSTAT, ST),
PROC(link, linkargs, void, none, RC_REPLSTAT, ST),
PROC(symlink, symlinkargs, void, none, RC_REPLSTAT, ST),
PROC(mkdir, createargs, diropres, fhandle, RC_REPLBUFF, ST+FH+AT),
PROC(rmdir, diropargs, void, none, RC_REPLSTAT, ST),
PROC(readdir, readdirargs, readdirres, none, RC_NOCACHE, 0),
PROC(statfs, fhandle, statfsres, none, RC_NOCACHE, ST+5),
};
struct svc_version nfsd_version2 = {
.vs_vers = 2,
.vs_nproc = 18,
.vs_proc = nfsd_procedures2,
.vs_dispatch = nfsd_dispatch,
.vs_xdrsize = NFS2_SVC_XDRSIZE,
};
/*
* Map errnos to NFS errnos.
*/
__be32
nfserrno (int errno)
{
static struct {
__be32 nfserr;
int syserr;
} nfs_errtbl[] = {
{ nfs_ok, 0 },
{ nfserr_perm, -EPERM },
{ nfserr_noent, -ENOENT },
{ nfserr_io, -EIO },
{ nfserr_nxio, -ENXIO },
{ nfserr_acces, -EACCES },
{ nfserr_exist, -EEXIST },
{ nfserr_xdev, -EXDEV },
{ nfserr_mlink, -EMLINK },
{ nfserr_nodev, -ENODEV },
{ nfserr_notdir, -ENOTDIR },
{ nfserr_isdir, -EISDIR },
{ nfserr_inval, -EINVAL },
{ nfserr_fbig, -EFBIG },
{ nfserr_nospc, -ENOSPC },
{ nfserr_rofs, -EROFS },
{ nfserr_mlink, -EMLINK },
{ nfserr_nametoolong, -ENAMETOOLONG },
{ nfserr_notempty, -ENOTEMPTY },
#ifdef EDQUOT
{ nfserr_dquot, -EDQUOT },
#endif
{ nfserr_stale, -ESTALE },
{ nfserr_jukebox, -ETIMEDOUT },
{ nfserr_jukebox, -ERESTARTSYS },
{ nfserr_dropit, -EAGAIN },
{ nfserr_dropit, -ENOMEM },
{ nfserr_badname, -ESRCH },
{ nfserr_io, -ETXTBSY },
{ nfserr_notsupp, -EOPNOTSUPP },
{ nfserr_toosmall, -ETOOSMALL },
};
int i;
for (i = 0; i < ARRAY_SIZE(nfs_errtbl); i++) {
if (nfs_errtbl[i].syserr == errno)
return nfs_errtbl[i].nfserr;
}
printk (KERN_INFO "nfsd: non-standard errno: %d\n", errno);
return nfserr_io;
}