NetBSD/sys/compat/svr4/svr4_fcntl.c
thorpej 80cc38a1af Fix a partial construction problem that can cause race conditions
between creation of a file descriptor and close(2) when using kernel
assisted threads.  What we do is stick descriptors in the table, but
mark them as "larval".  This causes essentially everything to treat
it as a non-existent descriptor, except for fdalloc(), which sees a
filled slot so that it won't (incorrectly) allocate it again.  When
a descriptor is fully constructed, the code that has constructed it
marks it as "mature" (which actually clears the "larval" flag), and
things continue to work as normal.

While here, gather all the code that gets a descriptor from the table
into a fd_getfile() function, and call it, rather than having the
same (sometimes incorrect) code copied all over the place.
2001-06-14 20:32:41 +00:00

746 lines
16 KiB
C

/* $NetBSD: svr4_fcntl.c,v 1.37 2001/06/14 20:32:45 thorpej Exp $ */
/*-
* Copyright (c) 1994, 1997 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Christos Zoulas.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/namei.h>
#include <sys/proc.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <sys/filedesc.h>
#include <sys/ioctl.h>
#include <sys/kernel.h>
#include <sys/mount.h>
#include <sys/malloc.h>
#include <sys/vnode.h>
#include <sys/syscallargs.h>
#include <compat/svr4/svr4_types.h>
#include <compat/svr4/svr4_signal.h>
#include <compat/svr4/svr4_ucontext.h>
#include <compat/svr4/svr4_lwp.h>
#include <compat/svr4/svr4_syscallargs.h>
#include <compat/svr4/svr4_util.h>
#include <compat/svr4/svr4_fcntl.h>
static u_long svr4_to_bsd_cmd __P((u_long));
static int svr4_to_bsd_flags __P((int));
static int bsd_to_svr4_flags __P((int));
static void bsd_to_svr4_flock __P((struct flock *, struct svr4_flock *));
static void svr4_to_bsd_flock __P((struct svr4_flock *, struct flock *));
static void bsd_to_svr4_flock64 __P((struct flock *, struct svr4_flock64 *));
static void svr4_to_bsd_flock64 __P((struct svr4_flock64 *, struct flock *));
static int fd_revoke __P((struct proc *, int, register_t *));
static int fd_truncate __P((struct proc *, int, struct flock *, register_t *));
static u_long
svr4_to_bsd_cmd(cmd)
u_long cmd;
{
switch (cmd) {
case SVR4_F_DUPFD:
return F_DUPFD;
case SVR4_F_GETFD:
return F_GETFD;
case SVR4_F_SETFD:
return F_SETFD;
case SVR4_F_GETFL:
return F_GETFL;
case SVR4_F_SETFL:
return F_SETFL;
case SVR4_F_GETLK:
return F_GETLK;
case SVR4_F_SETLK:
return F_SETLK;
case SVR4_F_SETLKW:
return F_SETLKW;
default:
return -1;
}
}
static int
svr4_to_bsd_flags(l)
int l;
{
int r = 0;
r |= (l & SVR4_O_RDONLY) ? O_RDONLY : 0;
r |= (l & SVR4_O_WRONLY) ? O_WRONLY : 0;
r |= (l & SVR4_O_RDWR) ? O_RDWR : 0;
r |= (l & SVR4_O_NDELAY) ? O_NDELAY : 0;
r |= (l & SVR4_O_APPEND) ? O_APPEND : 0;
r |= (l & SVR4_O_SYNC) ? O_FSYNC : 0;
r |= (l & SVR4_O_RSYNC) ? O_RSYNC : 0;
r |= (l & SVR4_O_DSYNC) ? O_DSYNC : 0;
r |= (l & SVR4_O_NONBLOCK) ? O_NONBLOCK : 0;
r |= (l & SVR4_O_PRIV) ? O_EXLOCK : 0;
r |= (l & SVR4_O_CREAT) ? O_CREAT : 0;
r |= (l & SVR4_O_TRUNC) ? O_TRUNC : 0;
r |= (l & SVR4_O_EXCL) ? O_EXCL : 0;
r |= (l & SVR4_O_NOCTTY) ? O_NOCTTY : 0;
return r;
}
static int
bsd_to_svr4_flags(l)
int l;
{
int r = 0;
r |= (l & O_RDONLY) ? SVR4_O_RDONLY : 0;
r |= (l & O_WRONLY) ? SVR4_O_WRONLY : 0;
r |= (l & O_RDWR) ? SVR4_O_RDWR : 0;
r |= (l & O_NDELAY) ? SVR4_O_NDELAY : 0;
r |= (l & O_APPEND) ? SVR4_O_APPEND : 0;
r |= (l & O_FSYNC) ? SVR4_O_SYNC : 0;
r |= (l & O_RSYNC) ? SVR4_O_RSYNC : 0;
r |= (l & O_DSYNC) ? SVR4_O_DSYNC : 0;
r |= (l & O_NONBLOCK) ? SVR4_O_NONBLOCK : 0;
r |= (l & O_EXLOCK) ? SVR4_O_PRIV : 0;
r |= (l & O_CREAT) ? SVR4_O_CREAT : 0;
r |= (l & O_TRUNC) ? SVR4_O_TRUNC : 0;
r |= (l & O_EXCL) ? SVR4_O_EXCL : 0;
r |= (l & O_NOCTTY) ? SVR4_O_NOCTTY : 0;
return r;
}
static void
bsd_to_svr4_flock(iflp, oflp)
struct flock *iflp;
struct svr4_flock *oflp;
{
switch (iflp->l_type) {
case F_RDLCK:
oflp->l_type = SVR4_F_RDLCK;
break;
case F_WRLCK:
oflp->l_type = SVR4_F_WRLCK;
break;
case F_UNLCK:
oflp->l_type = SVR4_F_UNLCK;
break;
default:
oflp->l_type = -1;
break;
}
oflp->l_whence = (short) iflp->l_whence;
oflp->l_start = (svr4_off_t) iflp->l_start;
oflp->l_len = (svr4_off_t) iflp->l_len;
oflp->l_sysid = 0;
oflp->l_pid = (svr4_pid_t) iflp->l_pid;
}
static void
svr4_to_bsd_flock(iflp, oflp)
struct svr4_flock *iflp;
struct flock *oflp;
{
switch (iflp->l_type) {
case SVR4_F_RDLCK:
oflp->l_type = F_RDLCK;
break;
case SVR4_F_WRLCK:
oflp->l_type = F_WRLCK;
break;
case SVR4_F_UNLCK:
oflp->l_type = F_UNLCK;
break;
default:
oflp->l_type = -1;
break;
}
oflp->l_whence = iflp->l_whence;
oflp->l_start = (off_t) iflp->l_start;
oflp->l_len = (off_t) iflp->l_len;
oflp->l_pid = (pid_t) iflp->l_pid;
}
static void
bsd_to_svr4_flock64(iflp, oflp)
struct flock *iflp;
struct svr4_flock64 *oflp;
{
switch (iflp->l_type) {
case F_RDLCK:
oflp->l_type = SVR4_F_RDLCK;
break;
case F_WRLCK:
oflp->l_type = SVR4_F_WRLCK;
break;
case F_UNLCK:
oflp->l_type = SVR4_F_UNLCK;
break;
default:
oflp->l_type = -1;
break;
}
oflp->l_whence = (short) iflp->l_whence;
oflp->l_start = (svr4_off64_t) iflp->l_start;
oflp->l_len = (svr4_off64_t) iflp->l_len;
oflp->l_sysid = 0;
oflp->l_pid = (svr4_pid_t) iflp->l_pid;
}
static void
svr4_to_bsd_flock64(iflp, oflp)
struct svr4_flock64 *iflp;
struct flock *oflp;
{
switch (iflp->l_type) {
case SVR4_F_RDLCK:
oflp->l_type = F_RDLCK;
break;
case SVR4_F_WRLCK:
oflp->l_type = F_WRLCK;
break;
case SVR4_F_UNLCK:
oflp->l_type = F_UNLCK;
break;
default:
oflp->l_type = -1;
break;
}
oflp->l_whence = iflp->l_whence;
oflp->l_start = (off_t) iflp->l_start;
oflp->l_len = (off_t) iflp->l_len;
oflp->l_pid = (pid_t) iflp->l_pid;
}
static int
fd_revoke(p, fd, retval)
struct proc *p;
int fd;
register_t *retval;
{
struct filedesc *fdp = p->p_fd;
struct file *fp;
struct vnode *vp;
struct vattr vattr;
int error;
if ((fp = fd_getfile(fdp, fd)) == NULL)
return EBADF;
switch (fp->f_type) {
case DTYPE_VNODE:
vp = (struct vnode *) fp->f_data;
case DTYPE_SOCKET:
return EINVAL;
default:
panic("svr4_fcntl(F_REVOKE)");
/*NOTREACHED*/
}
if (vp->v_type != VCHR && vp->v_type != VBLK) {
error = EINVAL;
goto out;
}
if ((error = VOP_GETATTR(vp, &vattr, p->p_ucred, p)) != 0)
goto out;
if (p->p_ucred->cr_uid != vattr.va_uid &&
(error = suser(p->p_ucred, &p->p_acflag)) != 0)
goto out;
if (vp->v_usecount > 1 || (vp->v_flag & VALIASED))
VOP_REVOKE(vp, REVOKEALL);
out:
vrele(vp);
return error;
}
static int
fd_truncate(p, fd, flp, retval)
struct proc *p;
int fd;
struct flock *flp;
register_t *retval;
{
struct filedesc *fdp = p->p_fd;
struct file *fp;
off_t start, length;
struct vnode *vp;
struct vattr vattr;
int error;
struct sys_ftruncate_args ft;
/*
* We only support truncating the file.
*/
if ((fp = fd_getfile(fdp, fd)) == NULL)
return EBADF;
vp = (struct vnode *)fp->f_data;
if (fp->f_type != DTYPE_VNODE || vp->v_type == VFIFO)
return ESPIPE;
if ((error = VOP_GETATTR(vp, &vattr, p->p_ucred, p)) != 0)
return error;
length = vattr.va_size;
switch (flp->l_whence) {
case SEEK_CUR:
start = fp->f_offset + flp->l_start;
break;
case SEEK_END:
start = flp->l_start + length;
break;
case SEEK_SET:
start = flp->l_start;
break;
default:
return EINVAL;
}
if (start + flp->l_len < length) {
/* We don't support free'ing in the middle of the file */
return EINVAL;
}
SCARG(&ft, fd) = fd;
SCARG(&ft, length) = start;
return sys_ftruncate(p, &ft, retval);
}
int
svr4_sys_open(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
struct svr4_sys_open_args *uap = v;
int error;
struct sys_open_args cup;
caddr_t sg = stackgap_init(p->p_emul);
SCARG(&cup, flags) = svr4_to_bsd_flags(SCARG(uap, flags));
if (SCARG(&cup, flags) & O_CREAT)
CHECK_ALT_CREAT(p, &sg, SCARG(uap, path));
else
CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
SCARG(&cup, path) = SCARG(uap, path);
SCARG(&cup, mode) = SCARG(uap, mode);
error = sys_open(p, &cup, retval);
if (error)
return error;
if (!(SCARG(&cup, flags) & O_NOCTTY) && SESS_LEADER(p) &&
!(p->p_flag & P_CONTROLT)) {
struct filedesc *fdp = p->p_fd;
struct file *fp;
fp = fd_getfile(fdp, *retval);
/* ignore any error, just give it a try */
if (fp != NULL && fp->f_type == DTYPE_VNODE)
(fp->f_ops->fo_ioctl) (fp, TIOCSCTTY, (caddr_t) 0, p);
}
return 0;
}
int
svr4_sys_open64(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
return svr4_sys_open(p, v, retval);
}
int
svr4_sys_creat(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
struct svr4_sys_creat_args *uap = v;
struct sys_open_args cup;
caddr_t sg = stackgap_init(p->p_emul);
CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
SCARG(&cup, path) = SCARG(uap, path);
SCARG(&cup, mode) = SCARG(uap, mode);
SCARG(&cup, flags) = O_WRONLY | O_CREAT | O_TRUNC;
return sys_open(p, &cup, retval);
}
int
svr4_sys_creat64(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
return svr4_sys_creat(p, v, retval);
}
int
svr4_sys_llseek(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
struct svr4_sys_llseek_args *uap = v;
struct sys_lseek_args ap;
SCARG(&ap, fd) = SCARG(uap, fd);
#if BYTE_ORDER == BIG_ENDIAN
SCARG(&ap, offset) = (((long long) SCARG(uap, offset1)) << 32) |
SCARG(uap, offset2);
#else
SCARG(&ap, offset) = (((long long) SCARG(uap, offset2)) << 32) |
SCARG(uap, offset1);
#endif
SCARG(&ap, whence) = SCARG(uap, whence);
return sys_lseek(p, &ap, retval);
}
int
svr4_sys_access(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
struct svr4_sys_access_args *uap = v;
struct sys_access_args cup;
caddr_t sg = stackgap_init(p->p_emul);
CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
SCARG(&cup, path) = SCARG(uap, path);
SCARG(&cup, flags) = SCARG(uap, flags);
return sys_access(p, &cup, retval);
}
int
svr4_sys_pread(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
struct svr4_sys_pread_args *uap = v;
struct sys_pread_args pra;
/*
* Just translate the args structure and call the NetBSD
* pread(2) system call (offset type is 64-bit in NetBSD).
*/
SCARG(&pra, fd) = SCARG(uap, fd);
SCARG(&pra, buf) = SCARG(uap, buf);
SCARG(&pra, nbyte) = SCARG(uap, nbyte);
SCARG(&pra, offset) = SCARG(uap, off);
return (sys_pread(p, &pra, retval));
}
int
svr4_sys_pread64(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
struct svr4_sys_pread64_args *uap = v;
struct sys_pread_args pra;
/*
* Just translate the args structure and call the NetBSD
* pread(2) system call (offset type is 64-bit in NetBSD).
*/
SCARG(&pra, fd) = SCARG(uap, fd);
SCARG(&pra, buf) = SCARG(uap, buf);
SCARG(&pra, nbyte) = SCARG(uap, nbyte);
SCARG(&pra, offset) = SCARG(uap, off);
return (sys_pread(p, &pra, retval));
}
int
svr4_sys_pwrite(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
struct svr4_sys_pwrite_args *uap = v;
struct sys_pwrite_args pwa;
/*
* Just translate the args structure and call the NetBSD
* pwrite(2) system call (offset type is 64-bit in NetBSD).
*/
SCARG(&pwa, fd) = SCARG(uap, fd);
SCARG(&pwa, buf) = SCARG(uap, buf);
SCARG(&pwa, nbyte) = SCARG(uap, nbyte);
SCARG(&pwa, offset) = SCARG(uap, off);
return (sys_pwrite(p, &pwa, retval));
}
int
svr4_sys_pwrite64(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
struct svr4_sys_pwrite64_args *uap = v;
struct sys_pwrite_args pwa;
/*
* Just translate the args structure and call the NetBSD
* pwrite(2) system call (offset type is 64-bit in NetBSD).
*/
SCARG(&pwa, fd) = SCARG(uap, fd);
SCARG(&pwa, buf) = SCARG(uap, buf);
SCARG(&pwa, nbyte) = SCARG(uap, nbyte);
SCARG(&pwa, offset) = SCARG(uap, off);
return (sys_pwrite(p, &pwa, retval));
}
int
svr4_sys_fcntl(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
struct svr4_sys_fcntl_args *uap = v;
int error;
struct sys_fcntl_args fa;
SCARG(&fa, fd) = SCARG(uap, fd);
SCARG(&fa, cmd) = svr4_to_bsd_cmd(SCARG(uap, cmd));
switch (SCARG(&fa, cmd)) {
case F_DUPFD:
case F_GETFD:
case F_SETFD:
SCARG(&fa, arg) = SCARG(uap, arg);
return sys_fcntl(p, &fa, retval);
case F_GETFL:
SCARG(&fa, arg) = SCARG(uap, arg);
error = sys_fcntl(p, &fa, retval);
if (error)
return error;
*retval = bsd_to_svr4_flags(*retval);
return error;
case F_SETFL:
{
/*
* we must save the O_ASYNC flag, as that is
* handled by ioctl(_, I_SETSIG, _) emulation.
*/
register_t flags;
int cmd;
cmd = SCARG(&fa, cmd); /* save it for a while */
SCARG(&fa, cmd) = F_GETFL;
if ((error = sys_fcntl(p, &fa, &flags)) != 0)
return error;
flags &= O_ASYNC;
flags |= svr4_to_bsd_flags((u_long) SCARG(uap, arg));
SCARG(&fa, cmd) = cmd;
SCARG(&fa, arg) = (void *) flags;
return sys_fcntl(p, &fa, retval);
}
case F_GETLK:
case F_SETLK:
case F_SETLKW:
{
struct svr4_flock ifl;
struct flock *flp, fl;
caddr_t sg = stackgap_init(p->p_emul);
flp = stackgap_alloc(&sg, sizeof(struct flock));
SCARG(&fa, arg) = (void *) flp;
error = copyin(SCARG(uap, arg), &ifl, sizeof ifl);
if (error)
return error;
svr4_to_bsd_flock(&ifl, &fl);
error = copyout(&fl, flp, sizeof fl);
if (error)
return error;
error = sys_fcntl(p, &fa, retval);
if (error || SCARG(&fa, cmd) != F_GETLK)
return error;
error = copyin(flp, &fl, sizeof fl);
if (error)
return error;
bsd_to_svr4_flock(&fl, &ifl);
return copyout(&ifl, SCARG(uap, arg), sizeof ifl);
}
case -1:
switch (SCARG(uap, cmd)) {
case SVR4_F_DUP2FD:
{
struct sys_dup2_args du;
SCARG(&du, from) = SCARG(uap, fd);
SCARG(&du, to) = (int)(u_long)SCARG(uap, arg);
error = sys_dup2(p, &du, retval);
if (error)
return error;
*retval = SCARG(&du, to);
return 0;
}
case SVR4_F_FREESP:
{
struct svr4_flock ifl;
struct flock fl;
error = copyin(SCARG(uap, arg), &ifl,
sizeof ifl);
if (error)
return error;
svr4_to_bsd_flock(&ifl, &fl);
return fd_truncate(p, SCARG(uap, fd), &fl,
retval);
}
case SVR4_F_GETLK64:
case SVR4_F_SETLK64:
case SVR4_F_SETLKW64:
{
struct svr4_flock64 ifl;
struct flock *flp, fl;
caddr_t sg = stackgap_init(p->p_emul);
flp = stackgap_alloc(&sg, sizeof(struct flock));
SCARG(&fa, arg) = (void *) flp;
error = copyin(SCARG(uap, arg), &ifl,
sizeof ifl);
if (error)
return error;
svr4_to_bsd_flock64(&ifl, &fl);
error = copyout(&fl, flp, sizeof fl);
if (error)
return error;
error = sys_fcntl(p, &fa, retval);
if (error || SCARG(&fa, cmd) != F_GETLK)
return error;
error = copyin(flp, &fl, sizeof fl);
if (error)
return error;
bsd_to_svr4_flock64(&fl, &ifl);
return copyout(&ifl, SCARG(uap, arg),
sizeof ifl);
}
case SVR4_F_FREESP64:
{
struct svr4_flock64 ifl;
struct flock fl;
error = copyin(SCARG(uap, arg), &ifl,
sizeof ifl);
if (error)
return error;
svr4_to_bsd_flock64(&ifl, &fl);
return fd_truncate(p, SCARG(uap, fd), &fl,
retval);
}
case SVR4_F_REVOKE:
return fd_revoke(p, SCARG(uap, fd), retval);
default:
return ENOSYS;
}
default:
return ENOSYS;
}
}