linux/fs/lockd/xdr.c
Benjamin Coddington b8eee0e90f lockd: Show pid of lockd for remote locks
Commit 9d5b86ac13 ("fs/locks: Remove fl_nspid and use fs-specific l_pid
for remote locks") specified that the l_pid returned for F_GETLK on a local
file that has a remote lock should be the pid of the lock manager process.
That commit, while updating other filesystems, failed to update lockd, such
that locks created by lockd had their fl_pid set to that of the remote
process holding the lock.  Fix that here to be the pid of lockd.

Also, fix the client case so that the returned lock pid is negative, which
indicates a remote lock on a remote file.

Fixes: 9d5b86ac13 ("fs/locks: Remove fl_nspid and use fs-specific...")
Cc: stable@vger.kernel.org

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-12-14 12:52:16 -05:00

356 lines
7.3 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* linux/fs/lockd/xdr.c
*
* XDR support for lockd and the lock client.
*
* Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
*/
#include <linux/types.h>
#include <linux/sched.h>
#include <linux/nfs.h>
#include <linux/sunrpc/xdr.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/svc.h>
#include <linux/sunrpc/stats.h>
#include <linux/lockd/lockd.h>
#include <uapi/linux/nfs2.h>
#define NLMDBG_FACILITY NLMDBG_XDR
static inline loff_t
s32_to_loff_t(__s32 offset)
{
return (loff_t)offset;
}
static inline __s32
loff_t_to_s32(loff_t offset)
{
__s32 res;
if (offset >= NLM_OFFSET_MAX)
res = NLM_OFFSET_MAX;
else if (offset <= -NLM_OFFSET_MAX)
res = -NLM_OFFSET_MAX;
else
res = offset;
return res;
}
/*
* XDR functions for basic NLM types
*/
static __be32 *nlm_decode_cookie(__be32 *p, struct nlm_cookie *c)
{
unsigned int len;
len = ntohl(*p++);
if(len==0)
{
c->len=4;
memset(c->data, 0, 4); /* hockeypux brain damage */
}
else if(len<=NLM_MAXCOOKIELEN)
{
c->len=len;
memcpy(c->data, p, len);
p+=XDR_QUADLEN(len);
}
else
{
dprintk("lockd: bad cookie size %d (only cookies under "
"%d bytes are supported.)\n",
len, NLM_MAXCOOKIELEN);
return NULL;
}
return p;
}
static inline __be32 *
nlm_encode_cookie(__be32 *p, struct nlm_cookie *c)
{
*p++ = htonl(c->len);
memcpy(p, c->data, c->len);
p+=XDR_QUADLEN(c->len);
return p;
}
static __be32 *
nlm_decode_fh(__be32 *p, struct nfs_fh *f)
{
unsigned int len;
if ((len = ntohl(*p++)) != NFS2_FHSIZE) {
dprintk("lockd: bad fhandle size %d (should be %d)\n",
len, NFS2_FHSIZE);
return NULL;
}
f->size = NFS2_FHSIZE;
memset(f->data, 0, sizeof(f->data));
memcpy(f->data, p, NFS2_FHSIZE);
return p + XDR_QUADLEN(NFS2_FHSIZE);
}
/*
* Encode and decode owner handle
*/
static inline __be32 *
nlm_decode_oh(__be32 *p, struct xdr_netobj *oh)
{
return xdr_decode_netobj(p, oh);
}
static inline __be32 *
nlm_encode_oh(__be32 *p, struct xdr_netobj *oh)
{
return xdr_encode_netobj(p, oh);
}
static __be32 *
nlm_decode_lock(__be32 *p, struct nlm_lock *lock)
{
struct file_lock *fl = &lock->fl;
s32 start, len, end;
if (!(p = xdr_decode_string_inplace(p, &lock->caller,
&lock->len,
NLM_MAXSTRLEN))
|| !(p = nlm_decode_fh(p, &lock->fh))
|| !(p = nlm_decode_oh(p, &lock->oh)))
return NULL;
lock->svid = ntohl(*p++);
locks_init_lock(fl);
fl->fl_owner = current->files;
fl->fl_pid = current->tgid;
fl->fl_flags = FL_POSIX;
fl->fl_type = F_RDLCK; /* as good as anything else */
start = ntohl(*p++);
len = ntohl(*p++);
end = start + len - 1;
fl->fl_start = s32_to_loff_t(start);
if (len == 0 || end < 0)
fl->fl_end = OFFSET_MAX;
else
fl->fl_end = s32_to_loff_t(end);
return p;
}
/*
* Encode result of a TEST/TEST_MSG call
*/
static __be32 *
nlm_encode_testres(__be32 *p, struct nlm_res *resp)
{
s32 start, len;
if (!(p = nlm_encode_cookie(p, &resp->cookie)))
return NULL;
*p++ = resp->status;
if (resp->status == nlm_lck_denied) {
struct file_lock *fl = &resp->lock.fl;
*p++ = (fl->fl_type == F_RDLCK)? xdr_zero : xdr_one;
*p++ = htonl(resp->lock.svid);
/* Encode owner handle. */
if (!(p = xdr_encode_netobj(p, &resp->lock.oh)))
return NULL;
start = loff_t_to_s32(fl->fl_start);
if (fl->fl_end == OFFSET_MAX)
len = 0;
else
len = loff_t_to_s32(fl->fl_end - fl->fl_start + 1);
*p++ = htonl(start);
*p++ = htonl(len);
}
return p;
}
/*
* First, the server side XDR functions
*/
int
nlmsvc_decode_testargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nlm_args *argp = rqstp->rq_argp;
u32 exclusive;
if (!(p = nlm_decode_cookie(p, &argp->cookie)))
return 0;
exclusive = ntohl(*p++);
if (!(p = nlm_decode_lock(p, &argp->lock)))
return 0;
if (exclusive)
argp->lock.fl.fl_type = F_WRLCK;
return xdr_argsize_check(rqstp, p);
}
int
nlmsvc_encode_testres(struct svc_rqst *rqstp, __be32 *p)
{
struct nlm_res *resp = rqstp->rq_resp;
if (!(p = nlm_encode_testres(p, resp)))
return 0;
return xdr_ressize_check(rqstp, p);
}
int
nlmsvc_decode_lockargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nlm_args *argp = rqstp->rq_argp;
u32 exclusive;
if (!(p = nlm_decode_cookie(p, &argp->cookie)))
return 0;
argp->block = ntohl(*p++);
exclusive = ntohl(*p++);
if (!(p = nlm_decode_lock(p, &argp->lock)))
return 0;
if (exclusive)
argp->lock.fl.fl_type = F_WRLCK;
argp->reclaim = ntohl(*p++);
argp->state = ntohl(*p++);
argp->monitor = 1; /* monitor client by default */
return xdr_argsize_check(rqstp, p);
}
int
nlmsvc_decode_cancargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nlm_args *argp = rqstp->rq_argp;
u32 exclusive;
if (!(p = nlm_decode_cookie(p, &argp->cookie)))
return 0;
argp->block = ntohl(*p++);
exclusive = ntohl(*p++);
if (!(p = nlm_decode_lock(p, &argp->lock)))
return 0;
if (exclusive)
argp->lock.fl.fl_type = F_WRLCK;
return xdr_argsize_check(rqstp, p);
}
int
nlmsvc_decode_unlockargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nlm_args *argp = rqstp->rq_argp;
if (!(p = nlm_decode_cookie(p, &argp->cookie))
|| !(p = nlm_decode_lock(p, &argp->lock)))
return 0;
argp->lock.fl.fl_type = F_UNLCK;
return xdr_argsize_check(rqstp, p);
}
int
nlmsvc_decode_shareargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nlm_args *argp = rqstp->rq_argp;
struct nlm_lock *lock = &argp->lock;
memset(lock, 0, sizeof(*lock));
locks_init_lock(&lock->fl);
lock->svid = ~(u32) 0;
lock->fl.fl_pid = current->tgid;
if (!(p = nlm_decode_cookie(p, &argp->cookie))
|| !(p = xdr_decode_string_inplace(p, &lock->caller,
&lock->len, NLM_MAXSTRLEN))
|| !(p = nlm_decode_fh(p, &lock->fh))
|| !(p = nlm_decode_oh(p, &lock->oh)))
return 0;
argp->fsm_mode = ntohl(*p++);
argp->fsm_access = ntohl(*p++);
return xdr_argsize_check(rqstp, p);
}
int
nlmsvc_encode_shareres(struct svc_rqst *rqstp, __be32 *p)
{
struct nlm_res *resp = rqstp->rq_resp;
if (!(p = nlm_encode_cookie(p, &resp->cookie)))
return 0;
*p++ = resp->status;
*p++ = xdr_zero; /* sequence argument */
return xdr_ressize_check(rqstp, p);
}
int
nlmsvc_encode_res(struct svc_rqst *rqstp, __be32 *p)
{
struct nlm_res *resp = rqstp->rq_resp;
if (!(p = nlm_encode_cookie(p, &resp->cookie)))
return 0;
*p++ = resp->status;
return xdr_ressize_check(rqstp, p);
}
int
nlmsvc_decode_notify(struct svc_rqst *rqstp, __be32 *p)
{
struct nlm_args *argp = rqstp->rq_argp;
struct nlm_lock *lock = &argp->lock;
if (!(p = xdr_decode_string_inplace(p, &lock->caller,
&lock->len, NLM_MAXSTRLEN)))
return 0;
argp->state = ntohl(*p++);
return xdr_argsize_check(rqstp, p);
}
int
nlmsvc_decode_reboot(struct svc_rqst *rqstp, __be32 *p)
{
struct nlm_reboot *argp = rqstp->rq_argp;
if (!(p = xdr_decode_string_inplace(p, &argp->mon, &argp->len, SM_MAXSTRLEN)))
return 0;
argp->state = ntohl(*p++);
memcpy(&argp->priv.data, p, sizeof(argp->priv.data));
p += XDR_QUADLEN(SM_PRIV_SIZE);
return xdr_argsize_check(rqstp, p);
}
int
nlmsvc_decode_res(struct svc_rqst *rqstp, __be32 *p)
{
struct nlm_res *resp = rqstp->rq_argp;
if (!(p = nlm_decode_cookie(p, &resp->cookie)))
return 0;
resp->status = *p++;
return xdr_argsize_check(rqstp, p);
}
int
nlmsvc_decode_void(struct svc_rqst *rqstp, __be32 *p)
{
return xdr_argsize_check(rqstp, p);
}
int
nlmsvc_encode_void(struct svc_rqst *rqstp, __be32 *p)
{
return xdr_ressize_check(rqstp, p);
}