NetBSD/sys/miscfs/procfs/procfs_subr.c

446 lines
12 KiB
C

/* $NetBSD: procfs_subr.c,v 1.113 2019/03/30 23:28:30 christos Exp $ */
/*-
* Copyright (c) 2006, 2007, 2008 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Andrew Doran.
*
* 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.
*
* 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.
*/
/*
* 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. 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_subr.c 8.6 (Berkeley) 5/14/95
*/
/*
* Copyright (c) 1994 Christopher G. Demetriou. All rights reserved.
* Copyright (c) 1993 Jan-Simon Pendry
*
* 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_subr.c 8.6 (Berkeley) 5/14/95
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: procfs_subr.c,v 1.113 2019/03/30 23:28:30 christos Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/fstrans.h>
#include <sys/vnode.h>
#include <sys/stat.h>
#include <sys/file.h>
#include <sys/filedesc.h>
#include <sys/kauth.h>
#include <sys/sysctl.h>
#include <miscfs/procfs/procfs.h>
/*
* Allocate a pfsnode/vnode pair. The vnode is referenced.
* The pid, type, and file descriptor uniquely identify a pfsnode.
*/
int
procfs_allocvp(struct mount *mp, struct vnode **vpp, pid_t pid,
pfstype type, int fd)
{
struct pfskey key;
memset(&key, 0, sizeof(key));
key.pk_type = type;
key.pk_pid = pid;
key.pk_fd = fd;
return vcache_get(mp, &key, sizeof(key), vpp);
}
int
procfs_rw(void *v)
{
struct vop_read_args *ap = v;
struct vnode *vp = ap->a_vp;
struct uio *uio = ap->a_uio;
struct lwp *curl;
struct lwp *l;
struct pfsnode *pfs = VTOPFS(vp);
struct proc *p;
int error;
if (uio->uio_offset < 0)
return EINVAL;
if ((error = procfs_proc_lock(pfs->pfs_pid, &p, ESRCH)) != 0)
return error;
curl = curlwp;
/*
* Do not allow init to be modified while in secure mode; it
* could be duped into changing the security level.
*/
#define M2K(m) ((m) == UIO_READ ? KAUTH_REQ_PROCESS_PROCFS_READ : \
KAUTH_REQ_PROCESS_PROCFS_WRITE)
mutex_enter(p->p_lock);
error = kauth_authorize_process(curl->l_cred, KAUTH_PROCESS_PROCFS,
p, pfs, KAUTH_ARG(M2K(uio->uio_rw)), NULL);
mutex_exit(p->p_lock);
if (error) {
procfs_proc_unlock(p);
return (error);
}
#undef M2K
mutex_enter(p->p_lock);
LIST_FOREACH(l, &p->p_lwps, l_sibling) {
if (l->l_stat != LSZOMB)
break;
}
/* Process is exiting if no-LWPS or all LWPs are LSZOMB */
if (l == NULL) {
mutex_exit(p->p_lock);
procfs_proc_unlock(p);
return ESRCH;
}
lwp_addref(l);
mutex_exit(p->p_lock);
switch (pfs->pfs_type) {
case PFSnote:
case PFSnotepg:
error = procfs_donote(curl, p, pfs, uio);
break;
case PFSregs:
error = procfs_doregs(curl, l, pfs, uio);
break;
case PFSfpregs:
error = procfs_dofpregs(curl, l, pfs, uio);
break;
case PFSstatus:
error = procfs_dostatus(curl, l, pfs, uio);
break;
case PFSstat:
error = procfs_do_pid_stat(curl, l, pfs, uio);
break;
case PFSlimit:
error = procfs_dolimit(curl, p, pfs, uio);
break;
case PFSmap:
error = procfs_domap(curl, p, pfs, uio, 0);
break;
case PFSmaps:
error = procfs_domap(curl, p, pfs, uio, 1);
break;
case PFSmem:
error = procfs_domem(curl, l, pfs, uio);
break;
case PFScmdline:
error = procfs_doprocargs(curl, p, pfs, uio, KERN_PROC_ARGV);
break;
case PFSenviron:
error = procfs_doprocargs(curl, p, pfs, uio, KERN_PROC_ENV);
break;
case PFSmeminfo:
error = procfs_domeminfo(curl, p, pfs, uio);
break;
case PFSdevices:
error = procfs_dodevices(curl, p, pfs, uio);
break;
case PFScpuinfo:
error = procfs_docpuinfo(curl, p, pfs, uio);
break;
case PFScpustat:
error = procfs_docpustat(curl, p, pfs, uio);
break;
case PFSloadavg:
error = procfs_doloadavg(curl, p, pfs, uio);
break;
case PFSstatm:
error = procfs_do_pid_statm(curl, l, pfs, uio);
break;
case PFSfd:
error = procfs_dofd(curl, p, pfs, uio);
break;
case PFSuptime:
error = procfs_douptime(curl, p, pfs, uio);
break;
case PFSmounts:
error = procfs_domounts(curl, p, pfs, uio);
break;
case PFSemul:
error = procfs_doemul(curl, p, pfs, uio);
break;
case PFSversion:
error = procfs_doversion(curl, p, pfs, uio);
break;
case PFSauxv:
error = procfs_doauxv(curl, p, pfs, uio);
break;
#ifdef __HAVE_PROCFS_MACHDEP
PROCFS_MACHDEP_NODETYPE_CASES
error = procfs_machdep_rw(curl, l, pfs, uio);
break;
#endif
default:
error = EOPNOTSUPP;
break;
}
/*
* Release the references that we acquired earlier.
*/
lwp_delref(l);
procfs_proc_unlock(p);
return (error);
}
/*
* Get a string from userland into (bf). Strip a trailing
* nl character (to allow easy access from the shell).
* The buffer should be *buflenp + 1 chars long. vfs_getuserstr
* will automatically add a nul char at the end.
*
* Returns 0 on success or the following errors
*
* EINVAL: file offset is non-zero.
* EMSGSIZE: message is longer than kernel buffer
* EFAULT: user i/o buffer is not addressable
*/
int
vfs_getuserstr(struct uio *uio, char *bf, int *buflenp)
{
int xlen;
int error;
if (uio->uio_offset != 0)
return (EINVAL);
xlen = *buflenp;
/* must be able to read the whole string in one go */
if (xlen < uio->uio_resid)
return (EMSGSIZE);
xlen = uio->uio_resid;
if ((error = uiomove(bf, xlen, uio)) != 0)
return (error);
/* allow multiple writes without seeks */
uio->uio_offset = 0;
/* cleanup string and remove trailing newline */
bf[xlen] = '\0';
xlen = strlen(bf);
if (xlen > 0 && bf[xlen-1] == '\n')
bf[--xlen] = '\0';
*buflenp = xlen;
return (0);
}
const vfs_namemap_t *
vfs_findname(const vfs_namemap_t *nm, const char *bf, int buflen)
{
for (; nm->nm_name; nm++)
if (memcmp(bf, nm->nm_name, buflen+1) == 0)
return (nm);
return (0);
}
static bool
procfs_revoke_selector(void *arg, struct vnode *vp)
{
struct proc *p = arg;
struct pfsnode *pfs;
KASSERT(mutex_owned(vp->v_interlock));
pfs = VTOPFS(vp);
return (pfs != NULL && pfs->pfs_pid == p->p_pid);
}
void
procfs_revoke_vnodes(struct proc *p, void *arg)
{
int error;
bool suspended;
struct vnode *vp;
struct vnode_iterator *marker;
struct mount *mp = (struct mount *)arg;
if (!(p->p_flag & PK_SUGID))
return;
suspended = false;
vfs_vnode_iterator_init(mp, &marker);
while ((vp = vfs_vnode_iterator_next(marker,
procfs_revoke_selector, p)) != NULL) {
if (vrecycle(vp))
continue;
/* Vnode is busy, we have to suspend the mount for vgone(). */
while (! suspended) {
error = vfs_suspend(mp, 0);
if (error == 0) {
suspended = true;
} else if (error != EINTR && error != ERESTART) {
KASSERT(error == EOPNOTSUPP);
break;
}
}
vgone(vp);
}
if (suspended)
vfs_resume(mp);
vfs_vnode_iterator_destroy(marker);
}
int
procfs_proc_lock(int pid, struct proc **bunghole, int notfound)
{
struct proc *tp;
int error = 0;
mutex_enter(proc_lock);
if (pid == 0)
tp = &proc0;
else if ((tp = proc_find(pid)) == NULL)
error = notfound;
if (tp != NULL && !rw_tryenter(&tp->p_reflock, RW_READER))
error = EBUSY;
mutex_exit(proc_lock);
*bunghole = tp;
return error;
}
void
procfs_proc_unlock(struct proc *p)
{
rw_exit(&p->p_reflock);
}
int
procfs_doemul(struct lwp *curl, struct proc *p,
struct pfsnode *pfs, struct uio *uio)
{
const char *ename = p->p_emul->e_name;
return uiomove_frombuf(__UNCONST(ename), strlen(ename), uio);
}