freebsd-dev/sys/fs/procfs/procfs.c
Jamie Gritton 0e5c6bd436 Make it easier for filesystems to count themselves as jail-enabled,
by doing most of the work in a new function prison_add_vfs in kern_jail.c
Now a jail-enabled filesystem need only mark itself with VFCF_JAIL, and
the rest is taken care of.  This includes adding a jail parameter like
allow.mount.foofs, and a sysctl like security.jail.mount_foofs_allowed.
Both of these used to be a static list of known filesystems, with
predefined permission bits.

Reviewed by:	kib
Differential Revision:	D14681
2018-05-04 20:54:27 +00:00

219 lines
5.8 KiB
C

/*-
* SPDX-License-Identifier: BSD-4-Clause
*
* Copyright (c) 2001 Dag-Erling Smørgrav
* Copyright (c) 1993 Jan-Simon Pendry
* Copyright (c) 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Jan-Simon Pendry.
*
* 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 University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
*
* @(#)procfs_vfsops.c 8.7 (Berkeley) 5/10/95
*
* $FreeBSD$
*/
#include <sys/param.h>
#include <sys/queue.h>
#include <sys/exec.h>
#include <sys/lock.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/sbuf.h>
#include <sys/sysproto.h>
#include <sys/systm.h>
#include <sys/vnode.h>
#include <vm/vm.h>
#include <vm/pmap.h>
#include <vm/vm_param.h>
#include <fs/pseudofs/pseudofs.h>
#include <fs/procfs/procfs.h>
/*
* Filler function for proc/pid/file
*/
int
procfs_doprocfile(PFS_FILL_ARGS)
{
char *fullpath;
char *freepath;
struct vnode *textvp;
int error;
freepath = NULL;
PROC_LOCK(p);
textvp = p->p_textvp;
vhold(textvp);
PROC_UNLOCK(p);
error = vn_fullpath(td, textvp, &fullpath, &freepath);
vdrop(textvp);
if (error == 0)
sbuf_printf(sb, "%s", fullpath);
if (freepath != NULL)
free(freepath, M_TEMP);
return (error);
}
/*
* Filler function for proc/curproc
*/
int
procfs_docurproc(PFS_FILL_ARGS)
{
sbuf_printf(sb, "%ld", (long)td->td_proc->p_pid);
return (0);
}
static int
procfs_attr(PFS_ATTR_ARGS, int mode) {
vap->va_mode = mode;
if (p != NULL) {
PROC_LOCK_ASSERT(p, MA_OWNED);
if ((p->p_flag & P_SUGID) && pn->pn_type != pfstype_procdir)
vap->va_mode = 0;
}
return (0);
}
int
procfs_attr_all_rx(PFS_ATTR_ARGS)
{
return (procfs_attr(td, p, pn, vap, 0555));
}
int
procfs_attr_rw(PFS_ATTR_ARGS)
{
return (procfs_attr(td, p, pn, vap, 0600));
}
int
procfs_attr_w(PFS_ATTR_ARGS)
{
return (procfs_attr(td, p, pn, vap, 0200));
}
/*
* Visibility: some files only exist for non-system processes
* Non-static because linprocfs uses it.
*/
int
procfs_notsystem(PFS_VIS_ARGS)
{
PROC_LOCK_ASSERT(p, MA_OWNED);
return ((p->p_flag & P_SYSTEM) == 0);
}
/*
* Visibility: some files are only visible to process that can debug
* the target process.
*/
int
procfs_candebug(PFS_VIS_ARGS)
{
PROC_LOCK_ASSERT(p, MA_OWNED);
return ((p->p_flag & P_SYSTEM) == 0 && p_candebug(td, p) == 0);
}
/*
* Constructor
*/
static int
procfs_init(PFS_INIT_ARGS)
{
struct pfs_node *root;
struct pfs_node *dir;
struct pfs_node *node;
root = pi->pi_root;
pfs_create_link(root, "curproc", procfs_docurproc,
NULL, NULL, NULL, 0);
dir = pfs_create_dir(root, "pid",
procfs_attr_all_rx, NULL, NULL, PFS_PROCDEP);
pfs_create_file(dir, "cmdline", procfs_doproccmdline,
NULL, NULL, NULL, PFS_RD);
pfs_create_file(dir, "dbregs", procfs_doprocdbregs,
procfs_attr_rw, procfs_candebug, NULL, PFS_RDWR | PFS_RAW);
pfs_create_file(dir, "etype", procfs_doproctype,
NULL, NULL, NULL, PFS_RD);
pfs_create_file(dir, "fpregs", procfs_doprocfpregs,
procfs_attr_rw, procfs_candebug, NULL, PFS_RDWR | PFS_RAW);
pfs_create_file(dir, "map", procfs_doprocmap,
NULL, procfs_notsystem, NULL, PFS_RD);
node = pfs_create_file(dir, "mem", procfs_doprocmem,
procfs_attr_rw, procfs_candebug, NULL, PFS_RDWR | PFS_RAW);
node->pn_ioctl = procfs_ioctl;
node->pn_close = procfs_close;
pfs_create_file(dir, "note", procfs_doprocnote,
procfs_attr_w, procfs_candebug, NULL, PFS_WR);
pfs_create_file(dir, "notepg", procfs_doprocnote,
procfs_attr_w, procfs_candebug, NULL, PFS_WR);
pfs_create_file(dir, "regs", procfs_doprocregs,
procfs_attr_rw, procfs_candebug, NULL, PFS_RDWR | PFS_RAW);
pfs_create_file(dir, "rlimit", procfs_doprocrlimit,
NULL, NULL, NULL, PFS_RD);
pfs_create_file(dir, "status", procfs_doprocstatus,
NULL, NULL, NULL, PFS_RD);
pfs_create_file(dir, "osrel", procfs_doosrel,
procfs_attr_rw, procfs_candebug, NULL, PFS_RDWR);
pfs_create_link(dir, "file", procfs_doprocfile,
NULL, procfs_notsystem, NULL, 0);
return (0);
}
/*
* Destructor
*/
static int
procfs_uninit(PFS_INIT_ARGS)
{
/* nothing to do, pseudofs will GC */
return (0);
}
PSEUDOFS(procfs, 1, VFCF_JAIL);