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/* $NetBSD: kern_proc.c,v 1.255 2020/06/11 19:20:46 ad Exp $ */
/*-
* Copyright (c) 1999, 2006, 2007, 2008, 2020 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
* NASA Ames Research Center, and 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) 1982, 1986, 1989, 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* 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.
*
* @(#)kern_proc.c 8.7 (Berkeley) 2/14/95
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: kern_proc.c,v 1.255 2020/06/11 19:20:46 ad Exp $");
#ifdef _KERNEL_OPT
#include "opt_kstack.h"
#include "opt_maxuprc.h"
#include "opt_dtrace.h"
#include "opt_compat_netbsd32.h"
#include "opt_kaslr.h"
#endif
#if defined(__HAVE_COMPAT_NETBSD32) && !defined(COMPAT_NETBSD32) \
&& !defined(_RUMPKERNEL)
#define COMPAT_NETBSD32
#endif
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/resourcevar.h>
#include <sys/buf.h>
#include <sys/acct.h>
#include <sys/wait.h>
#include <sys/file.h>
#include <ufs/ufs/quota.h>
#include <sys/uio.h>
#include <sys/pool.h>
#include <sys/pset.h>
#include <sys/ioctl.h>
#include <sys/tty.h>
#include <sys/signalvar.h>
#include <sys/ras.h>
#include <sys/filedesc.h>
#include <sys/syscall_stats.h>
#include <sys/kauth.h>
#include <sys/sleepq.h>
#include <sys/atomic.h>
#include <sys/kmem.h>
#include <sys/namei.h>
#include <sys/dtrace_bsd.h>
#include <sys/sysctl.h>
#include <sys/exec.h>
#include <sys/cpu.h>
#include <sys/compat_stub.h>
#include <sys/futex.h>
#include <sys/pserialize.h>
#include <uvm/uvm_extern.h>
#include <uvm/uvm.h>
/*
* Process lists.
*/
struct proclist allproc __cacheline_aligned;
struct proclist zombproc __cacheline_aligned;
kmutex_t proc_lock __cacheline_aligned;
static pserialize_t proc_psz;
/*
* pid to lwp/proc lookup is done by indexing the pid_table array.
* Since pid numbers are only allocated when an empty slot
* has been found, there is no need to search any lists ever.
* (an orphaned pgrp will lock the slot, a session will lock
* the pgrp with the same number.)
* If the table is too small it is reallocated with twice the
* previous size and the entries 'unzipped' into the two halves.
* A linked list of free entries is passed through the pt_lwp
* field of 'free' items - set odd to be an invalid ptr. Two
* additional bits are also used to indicate if the slot is
* currently occupied by a proc or lwp, and if the PID is
* hidden from certain kinds of lookups. We thus require a
* minimum alignment for proc and lwp structures (LWPs are
* at least 32-byte aligned).
*/
struct pid_table {
uintptr_t pt_slot;
struct pgrp *pt_pgrp;
pid_t pt_pid;
};
#define PT_F_FREE ((uintptr_t)__BIT(0))
#define PT_F_LWP 0 /* pseudo-flag */
#define PT_F_PROC ((uintptr_t)__BIT(1))
#define PT_F_TYPEBITS (PT_F_FREE|PT_F_PROC)
#define PT_F_ALLBITS (PT_F_FREE|PT_F_PROC)
#define PT_VALID(s) (((s) & PT_F_FREE) == 0)
#define PT_RESERVED(s) ((s) == 0)
#define PT_NEXT(s) ((u_int)(s) >> 1)
#define PT_SET_FREE(pid) (((pid) << 1) | PT_F_FREE)
#define PT_SET_LWP(l) ((uintptr_t)(l))
#define PT_SET_PROC(p) (((uintptr_t)(p)) | PT_F_PROC)
#define PT_SET_RESERVED 0
#define PT_GET_LWP(s) ((struct lwp *)((s) & ~PT_F_ALLBITS))
#define PT_GET_PROC(s) ((struct proc *)((s) & ~PT_F_ALLBITS))
#define PT_GET_TYPE(s) ((s) & PT_F_TYPEBITS)
#define PT_IS_LWP(s) (PT_GET_TYPE(s) == PT_F_LWP && (s) != 0)
#define PT_IS_PROC(s) (PT_GET_TYPE(s) == PT_F_PROC)
#define MIN_PROC_ALIGNMENT (PT_F_ALLBITS + 1)
/*
* Table of process IDs (PIDs).
*/
static struct pid_table *pid_table __read_mostly;
#define INITIAL_PID_TABLE_SIZE (1 << 5)
/* Table mask, threshold for growing and number of allocated PIDs. */
static u_int pid_tbl_mask __read_mostly;
static u_int pid_alloc_lim __read_mostly;
static u_int pid_alloc_cnt __cacheline_aligned;
/* Next free, last free and maximum PIDs. */
static u_int next_free_pt __cacheline_aligned;
static u_int last_free_pt __cacheline_aligned;
static pid_t pid_max __read_mostly;
/* Components of the first process -- never freed. */
extern struct emul emul_netbsd; /* defined in kern_exec.c */
struct session session0 = {
.s_count = 1,
.s_sid = 0,
};
struct pgrp pgrp0 = {
.pg_members = LIST_HEAD_INITIALIZER(&pgrp0.pg_members),
.pg_session = &session0,
};
filedesc_t filedesc0;
struct cwdinfo cwdi0 = {
.cwdi_cmask = CMASK,
.cwdi_refcnt = 1,
};
struct plimit limit0;
struct pstats pstat0;
struct vmspace vmspace0;
struct sigacts sigacts0;
struct proc proc0 = {
.p_lwps = LIST_HEAD_INITIALIZER(&proc0.p_lwps),
.p_sigwaiters = LIST_HEAD_INITIALIZER(&proc0.p_sigwaiters),
.p_nlwps = 1,
.p_nrlwps = 1,
.p_pgrp = &pgrp0,
.p_comm = "system",
/*
* Set P_NOCLDWAIT so that kernel threads are reparented to init(8)
* when they exit. init(8) can easily wait them out for us.
*/
.p_flag = PK_SYSTEM | PK_NOCLDWAIT,
.p_stat = SACTIVE,
.p_nice = NZERO,
.p_emul = &emul_netbsd,
.p_cwdi = &cwdi0,
.p_limit = &limit0,
.p_fd = &filedesc0,
.p_vmspace = &vmspace0,
.p_stats = &pstat0,
.p_sigacts = &sigacts0,
#ifdef PROC0_MD_INITIALIZERS
PROC0_MD_INITIALIZERS
#endif
};
kauth_cred_t cred0;
static const int nofile = NOFILE;
static const int maxuprc = MAXUPRC;
static int sysctl_doeproc(SYSCTLFN_PROTO);
static int sysctl_kern_proc_args(SYSCTLFN_PROTO);
static int sysctl_security_expose_address(SYSCTLFN_PROTO);
#ifdef KASLR
static int kern_expose_address = 0;
#else
static int kern_expose_address = 1;
#endif
/*
* The process list descriptors, used during pid allocation and
* by sysctl. No locking on this data structure is needed since
* it is completely static.
*/
const struct proclist_desc proclists[] = {
{ &allproc },
{ &zombproc },
{ NULL },
};
static struct pgrp * pg_remove(pid_t);
static void pg_delete(pid_t);
static void orphanpg(struct pgrp *);
static specificdata_domain_t proc_specificdata_domain;
static pool_cache_t proc_cache;
static kauth_listener_t proc_listener;
static void fill_proc(const struct proc *, struct proc *, bool);
static int fill_pathname(struct lwp *, pid_t, void *, size_t *);
static int fill_cwd(struct lwp *, pid_t, void *, size_t *);
static int
proc_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie,
void *arg0, void *arg1, void *arg2, void *arg3)
{
struct proc *p;
int result;
result = KAUTH_RESULT_DEFER;
p = arg0;
switch (action) {
case KAUTH_PROCESS_CANSEE: {
enum kauth_process_req req;
req = (enum kauth_process_req)(uintptr_t)arg1;
switch (req) {
case KAUTH_REQ_PROCESS_CANSEE_ARGS:
case KAUTH_REQ_PROCESS_CANSEE_ENTRY:
case KAUTH_REQ_PROCESS_CANSEE_OPENFILES:
case KAUTH_REQ_PROCESS_CANSEE_EPROC:
result = KAUTH_RESULT_ALLOW;
break;
case KAUTH_REQ_PROCESS_CANSEE_ENV:
if (kauth_cred_getuid(cred) !=
kauth_cred_getuid(p->p_cred) ||
kauth_cred_getuid(cred) !=
kauth_cred_getsvuid(p->p_cred))
break;
result = KAUTH_RESULT_ALLOW;
break;
case KAUTH_REQ_PROCESS_CANSEE_KPTR:
if (!kern_expose_address)
break;
if (kern_expose_address == 1 && !(p->p_flag & PK_KMEM))
break;
result = KAUTH_RESULT_ALLOW;
break;
default:
break;
}
break;
}
case KAUTH_PROCESS_FORK: {
int lnprocs = (int)(unsigned long)arg2;
/*
* Don't allow a nonprivileged user to use the last few
* processes. The variable lnprocs is the current number of
* processes, maxproc is the limit.
*/
if (__predict_false((lnprocs >= maxproc - 5)))
break;
result = KAUTH_RESULT_ALLOW;
break;
}
case KAUTH_PROCESS_CORENAME:
case KAUTH_PROCESS_STOPFLAG:
if (proc_uidmatch(cred, p->p_cred) == 0)
result = KAUTH_RESULT_ALLOW;
break;
default:
break;
}
return result;
}
static int
proc_ctor(void *arg __unused, void *obj, int flags __unused)
{
memset(obj, 0, sizeof(struct proc));
return 0;
}
static pid_t proc_alloc_pid_slot(struct proc *, uintptr_t);
/*
* Initialize global process hashing structures.
*/
void
procinit(void)
{
const struct proclist_desc *pd;
u_int i;
#define LINK_EMPTY ((PID_MAX + INITIAL_PID_TABLE_SIZE) & ~(INITIAL_PID_TABLE_SIZE - 1))
for (pd = proclists; pd->pd_list != NULL; pd++)
LIST_INIT(pd->pd_list);
mutex_init(&proc_lock, MUTEX_DEFAULT, IPL_NONE);
proc_psz = pserialize_create();
pid_table = kmem_alloc(INITIAL_PID_TABLE_SIZE
* sizeof(struct pid_table), KM_SLEEP);
pid_tbl_mask = INITIAL_PID_TABLE_SIZE - 1;
pid_max = PID_MAX;
/* Set free list running through table...
Preset 'use count' above PID_MAX so we allocate pid 1 next. */
for (i = 0; i <= pid_tbl_mask; i++) {
pid_table[i].pt_slot = PT_SET_FREE(LINK_EMPTY + i + 1);
pid_table[i].pt_pgrp = 0;
pid_table[i].pt_pid = 0;
}
/* slot 0 is just grabbed */
next_free_pt = 1;
/* Need to fix last entry. */
last_free_pt = pid_tbl_mask;
pid_table[last_free_pt].pt_slot = PT_SET_FREE(LINK_EMPTY);
/* point at which we grow table - to avoid reusing pids too often */
pid_alloc_lim = pid_tbl_mask - 1;
#undef LINK_EMPTY
/* Reserve PID 1 for init(8). */ /* XXX slightly gross */
mutex_enter(&proc_lock);
if (proc_alloc_pid_slot(&proc0, PT_SET_RESERVED) != 1)
panic("failed to reserve PID 1 for init(8)");
mutex_exit(&proc_lock);
proc_specificdata_domain = specificdata_domain_create();
KASSERT(proc_specificdata_domain != NULL);
size_t proc_alignment = coherency_unit;
if (proc_alignment < MIN_PROC_ALIGNMENT)
proc_alignment = MIN_PROC_ALIGNMENT;
proc_cache = pool_cache_init(sizeof(struct proc), proc_alignment, 0, 0,
"procpl", NULL, IPL_NONE, proc_ctor, NULL, NULL);
proc_listener = kauth_listen_scope(KAUTH_SCOPE_PROCESS,
proc_listener_cb, NULL);
}
void
procinit_sysctl(void)
{
static struct sysctllog *clog;
sysctl_createv(&clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "expose_address",
SYSCTL_DESCR("Enable exposing kernel addresses"),
sysctl_security_expose_address, 0,
&kern_expose_address, 0, CTL_KERN, CTL_CREATE, CTL_EOL);
sysctl_createv(&clog, 0, NULL, NULL,
CTLFLAG_PERMANENT,
CTLTYPE_NODE, "proc",
SYSCTL_DESCR("System-wide process information"),
sysctl_doeproc, 0, NULL, 0,
CTL_KERN, KERN_PROC, CTL_EOL);
sysctl_createv(&clog, 0, NULL, NULL,
CTLFLAG_PERMANENT,
CTLTYPE_NODE, "proc2",
SYSCTL_DESCR("Machine-independent process information"),
sysctl_doeproc, 0, NULL, 0,
CTL_KERN, KERN_PROC2, CTL_EOL);
sysctl_createv(&clog, 0, NULL, NULL,
CTLFLAG_PERMANENT,
CTLTYPE_NODE, "proc_args",
SYSCTL_DESCR("Process argument information"),
sysctl_kern_proc_args, 0, NULL, 0,
CTL_KERN, KERN_PROC_ARGS, CTL_EOL);
/*
"nodes" under these:
KERN_PROC_ALL
KERN_PROC_PID pid
KERN_PROC_PGRP pgrp
KERN_PROC_SESSION sess
KERN_PROC_TTY tty
KERN_PROC_UID uid
KERN_PROC_RUID uid
KERN_PROC_GID gid
KERN_PROC_RGID gid
all in all, probably not worth the effort...
*/
}
/*
* Initialize process 0.
*/
void
proc0_init(void)
{
struct proc *p;
struct pgrp *pg;
struct rlimit *rlim;
rlim_t lim;
int i;
p = &proc0;
pg = &pgrp0;
mutex_init(&p->p_stmutex, MUTEX_DEFAULT, IPL_HIGH);
mutex_init(&p->p_auxlock, MUTEX_DEFAULT, IPL_NONE);
p->p_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NONE);
rw_init(&p->p_reflock);
cv_init(&p->p_waitcv, "wait");
cv_init(&p->p_lwpcv, "lwpwait");
LIST_INSERT_HEAD(&p->p_lwps, &lwp0, l_sibling);
KASSERT(lwp0.l_lid == 0);
pid_table[lwp0.l_lid].pt_slot = PT_SET_LWP(&lwp0);
LIST_INSERT_HEAD(&allproc, p, p_list);
pid_table[lwp0.l_lid].pt_pgrp = pg;
LIST_INSERT_HEAD(&pg->pg_members, p, p_pglist);
#ifdef __HAVE_SYSCALL_INTERN
(*p->p_emul->e_syscall_intern)(p);
#endif
/* Create credentials. */
cred0 = kauth_cred_alloc();
p->p_cred = cred0;
/* Create the CWD info. */
rw_init(&cwdi0.cwdi_lock);
/* Create the limits structures. */
mutex_init(&limit0.pl_lock, MUTEX_DEFAULT, IPL_NONE);
rlim = limit0.pl_rlimit;
for (i = 0; i < __arraycount(limit0.pl_rlimit); i++) {
rlim[i].rlim_cur = RLIM_INFINITY;
rlim[i].rlim_max = RLIM_INFINITY;
}
rlim[RLIMIT_NOFILE].rlim_max = maxfiles;
rlim[RLIMIT_NOFILE].rlim_cur = maxfiles < nofile ? maxfiles : nofile;
rlim[RLIMIT_NPROC].rlim_max = maxproc;
rlim[RLIMIT_NPROC].rlim_cur = maxproc < maxuprc ? maxproc : maxuprc;
lim = MIN(VM_MAXUSER_ADDRESS, ctob((rlim_t)uvm_availmem(false)));
rlim[RLIMIT_RSS].rlim_max = lim;
rlim[RLIMIT_MEMLOCK].rlim_max = lim;
rlim[RLIMIT_MEMLOCK].rlim_cur = lim / 3;
rlim[RLIMIT_NTHR].rlim_max = maxlwp;
rlim[RLIMIT_NTHR].rlim_cur = maxlwp < maxuprc ? maxlwp : maxuprc;
/* Note that default core name has zero length. */
limit0.pl_corename = defcorename;
limit0.pl_cnlen = 0;
limit0.pl_refcnt = 1;
limit0.pl_writeable = false;
limit0.pl_sv_limit = NULL;
/* Configure virtual memory system, set vm rlimits. */
uvm_init_limits(p);
/* Initialize file descriptor table for proc0. */
fd_init(&filedesc0);
/*
* Initialize proc0's vmspace, which uses the kernel pmap.
* All kernel processes (which never have user space mappings)
* share proc0's vmspace, and thus, the kernel pmap.
*/
uvmspace_init(&vmspace0, pmap_kernel(), round_page(VM_MIN_ADDRESS),
trunc_page(VM_MAXUSER_ADDRESS),
#ifdef __USE_TOPDOWN_VM
true
#else
false
#endif
);
/* Initialize signal state for proc0. XXX IPL_SCHED */
mutex_init(&p->p_sigacts->sa_mutex, MUTEX_DEFAULT, IPL_SCHED);
siginit(p);
proc_initspecific(p);
kdtrace_proc_ctor(NULL, p);
}
/*
* Session reference counting.
*/
void
proc_sesshold(struct session *ss)
{
KASSERT(mutex_owned(&proc_lock));
ss->s_count++;
}
void
proc_sessrele(struct session *ss)
{
struct pgrp *pg;
KASSERT(mutex_owned(&proc_lock));
KASSERT(ss->s_count > 0);
/*
* We keep the pgrp with the same id as the session in order to
* stop a process being given the same pid. Since the pgrp holds
* a reference to the session, it must be a 'zombie' pgrp by now.
*/
if (--ss->s_count == 0) {
pg = pg_remove(ss->s_sid);
} else {
pg = NULL;
ss = NULL;
}
mutex_exit(&proc_lock);
if (pg)
kmem_free(pg, sizeof(struct pgrp));
if (ss)
kmem_free(ss, sizeof(struct session));
}
/*
* Check that the specified process group is in the session of the
* specified process.
* Treats -ve ids as process ids.
* Used to validate TIOCSPGRP requests.
*/
int
pgid_in_session(struct proc *p, pid_t pg_id)
{
struct pgrp *pgrp;
struct session *session;
int error;
mutex_enter(&proc_lock);
if (pg_id < 0) {
struct proc *p1 = proc_find(-pg_id);
if (p1 == NULL) {
error = EINVAL;
goto fail;
}
pgrp = p1->p_pgrp;
} else {
pgrp = pgrp_find(pg_id);
if (pgrp == NULL) {
error = EINVAL;
goto fail;
}
}
session = pgrp->pg_session;
error = (session != p->p_pgrp->pg_session) ? EPERM : 0;
fail:
mutex_exit(&proc_lock);
return error;
}
/*
* p_inferior: is p an inferior of q?
*/
static inline bool
p_inferior(struct proc *p, struct proc *q)
{
KASSERT(mutex_owned(&proc_lock));
for (; p != q; p = p->p_pptr)
if (p->p_pid == 0)
return false;
return true;
}
/*
* proc_find_lwp: locate an lwp in said proc by the ID.
*
* => Must be called with p::p_lock held.
* => LSIDL lwps are not returned because they are only partially
* constructed while occupying the slot.
* => Callers need to be careful about lwp::l_stat of the returned
* lwp.
*/
struct lwp *
proc_find_lwp(proc_t *p, pid_t pid)
{
struct pid_table *pt;
struct lwp *l = NULL;
uintptr_t slot;
int s;
KASSERT(mutex_owned(p->p_lock));
/*
* Look in the pid_table. This is done unlocked inside a pserialize
* read section covering pid_table's memory allocation only, so take
* care to read the slot atomically and only once. This issues a
* memory barrier for dependent loads on alpha.
*/
s = pserialize_read_enter();
pt = &pid_table[pid & pid_tbl_mask];
slot = atomic_load_consume(&pt->pt_slot);
if (__predict_false(!PT_IS_LWP(slot))) {
pserialize_read_exit(s);
return NULL;
}
/*
* Check to see if the LWP is from the correct process. We won't
* see entries in pid_table from a prior process that also used "p",
* by virtue of the fact that allocating "p" means all prior updates
* to dependant data structures are visible to this thread.
*/
l = PT_GET_LWP(slot);
if (__predict_false(atomic_load_relaxed(&l->l_proc) != p)) {
pserialize_read_exit(s);
return NULL;
}
/*
* We now know that p->p_lock holds this LWP stable.
*
* If the status is not LSIDL, it means the LWP is intended to be
* findable by LID and l_lid cannot change behind us.
*
* No need to acquire the LWP's lock to check for LSIDL, as
* p->p_lock must be held to transition in and out of LSIDL.
* Any other observed state of is no particular interest.
*/
pserialize_read_exit(s);
return l->l_stat != LSIDL && l->l_lid == pid ? l : NULL;
}
/*
* proc_find_lwp_unlocked: locate an lwp in said proc by the ID.
*
* => Called in a pserialize read section with no locks held.
* => LSIDL lwps are not returned because they are only partially
* constructed while occupying the slot.
* => Callers need to be careful about lwp::l_stat of the returned
* lwp.
* => If an LWP is found, it's returned locked.
*/
struct lwp *
proc_find_lwp_unlocked(proc_t *p, pid_t pid)
{
struct pid_table *pt;
struct lwp *l = NULL;
uintptr_t slot;
KASSERT(pserialize_in_read_section());
/*
* Look in the pid_table. This is done unlocked inside a pserialize
* read section covering pid_table's memory allocation only, so take
* care to read the slot atomically and only once. This issues a
* memory barrier for dependent loads on alpha.
*/
pt = &pid_table[pid & pid_tbl_mask];
slot = atomic_load_consume(&pt->pt_slot);
if (__predict_false(!PT_IS_LWP(slot))) {
return NULL;
}
/*
* Lock the LWP we found to get it stable. If it's embryonic or
* reaped (LSIDL) then none of the other fields can safely be
* checked.
*/
l = PT_GET_LWP(slot);
lwp_lock(l);
if (__predict_false(l->l_stat == LSIDL)) {
lwp_unlock(l);
return NULL;
}
/*
* l_proc and l_lid are now known stable because the LWP is not
* LSIDL, so check those fields too to make sure we found the
* right thing.
*/
if (__predict_false(l->l_proc != p || l->l_lid != pid)) {
lwp_unlock(l);
return NULL;
}
/* Everything checks out, return it locked. */
return l;
}
/*
* proc_find_lwp_acquire_proc: locate an lwp and acquire a lock
* on its containing proc.
*
* => Similar to proc_find_lwp(), but does not require you to have
* the proc a priori.
* => Also returns proc * to caller, with p::p_lock held.
* => Same caveats apply.
*/
struct lwp *
proc_find_lwp_acquire_proc(pid_t pid, struct proc **pp)
{
struct pid_table *pt;
struct proc *p = NULL;
struct lwp *l = NULL;
uintptr_t slot;
KASSERT(pp != NULL);
mutex_enter(&proc_lock);
pt = &pid_table[pid & pid_tbl_mask];
slot = pt->pt_slot;
if (__predict_true(PT_IS_LWP(slot) && pt->pt_pid == pid)) {
l = PT_GET_LWP(slot);
p = l->l_proc;
mutex_enter(p->p_lock);
if (__predict_false(l->l_stat == LSIDL)) {
mutex_exit(p->p_lock);
l = NULL;
p = NULL;
}
}
mutex_exit(&proc_lock);
KASSERT(p == NULL || mutex_owned(p->p_lock));
*pp = p;
return l;
}
/*
* proc_find_raw_pid_table_locked: locate a process by the ID.
*
* => Must be called with proc_lock held.
*/
static proc_t *
proc_find_raw_pid_table_locked(pid_t pid, bool any_lwpid)
{
struct pid_table *pt;
proc_t *p = NULL;
uintptr_t slot;
/* No - used by DDB. KASSERT(mutex_owned(&proc_lock)); */
pt = &pid_table[pid & pid_tbl_mask];
slot = pt->pt_slot;
if (__predict_true(PT_IS_LWP(slot) && pt->pt_pid == pid)) {
/*
* When looking up processes, require a direct match
* on the PID assigned to the proc, not just one of
* its LWPs.
*
* N.B. We require lwp::l_proc of LSIDL LWPs to be
* valid here.
*/
p = PT_GET_LWP(slot)->l_proc;
if (__predict_false(p->p_pid != pid && !any_lwpid))
p = NULL;
} else if (PT_IS_PROC(slot) && pt->pt_pid == pid) {
p = PT_GET_PROC(slot);
}
return p;
}
proc_t *
proc_find_raw(pid_t pid)
{
return proc_find_raw_pid_table_locked(pid, false);
}
static proc_t *
proc_find_internal(pid_t pid, bool any_lwpid)
{
proc_t *p;
KASSERT(mutex_owned(&proc_lock));
p = proc_find_raw_pid_table_locked(pid, any_lwpid);
if (__predict_false(p == NULL)) {
return NULL;
}
/*
* Only allow live processes to be found by PID.
* XXX: p_stat might change, since proc unlocked.
*/
if (__predict_true(p->p_stat == SACTIVE || p->p_stat == SSTOP)) {
return p;
}
return NULL;
}
proc_t *
proc_find(pid_t pid)
{
return proc_find_internal(pid, false);
}
proc_t *
proc_find_lwpid(pid_t pid)
{
return proc_find_internal(pid, true);
}
/*
* pgrp_find: locate a process group by the ID.
*
* => Must be called with proc_lock held.
*/
struct pgrp *
pgrp_find(pid_t pgid)
{
struct pgrp *pg;
KASSERT(mutex_owned(&proc_lock));
pg = pid_table[pgid & pid_tbl_mask].pt_pgrp;
/*
* Cannot look up a process group that only exists because the
* session has not died yet (traditional).
*/
if (pg == NULL || pg->pg_id != pgid || LIST_EMPTY(&pg->pg_members)) {
return NULL;
}
return pg;
}
static void
expand_pid_table(void)
{
size_t pt_size, tsz;
struct pid_table *n_pt, *new_pt;
uintptr_t slot;
struct pgrp *pgrp;
pid_t pid, rpid;
u_int i;
uint new_pt_mask;
KASSERT(mutex_owned(&proc_lock));
/* Unlock the pid_table briefly to allocate memory. */
pt_size = pid_tbl_mask + 1;
mutex_exit(&proc_lock);
tsz = pt_size * 2 * sizeof(struct pid_table);
new_pt = kmem_alloc(tsz, KM_SLEEP);
new_pt_mask = pt_size * 2 - 1;
/* XXX For now. The pratical limit is much lower anyway. */
KASSERT(new_pt_mask <= FUTEX_TID_MASK);
mutex_enter(&proc_lock);
if (pt_size != pid_tbl_mask + 1) {
/* Another process beat us to it... */
mutex_exit(&proc_lock);
kmem_free(new_pt, tsz);
goto out;
}
/*
* Copy entries from old table into new one.
* If 'pid' is 'odd' we need to place in the upper half,
* even pid's to the lower half.
* Free items stay in the low half so we don't have to
* fixup the reference to them.
* We stuff free items on the front of the freelist
* because we can't write to unmodified entries.
* Processing the table backwards maintains a semblance
* of issuing pid numbers that increase with time.
*/
i = pt_size - 1;
n_pt = new_pt + i;
for (; ; i--, n_pt--) {
slot = pid_table[i].pt_slot;
pgrp = pid_table[i].pt_pgrp;
if (!PT_VALID(slot)) {
/* Up 'use count' so that link is valid */
pid = (PT_NEXT(slot) + pt_size) & ~pt_size;
rpid = 0;
slot = PT_SET_FREE(pid);
if (pgrp)
pid = pgrp->pg_id;
} else {
pid = pid_table[i].pt_pid;
rpid = pid;
}
/* Save entry in appropriate half of table */
n_pt[pid & pt_size].pt_slot = slot;
n_pt[pid & pt_size].pt_pgrp = pgrp;
n_pt[pid & pt_size].pt_pid = rpid;
/* Put other piece on start of free list */
pid = (pid ^ pt_size) & ~pid_tbl_mask;
n_pt[pid & pt_size].pt_slot =
PT_SET_FREE((pid & ~pt_size) | next_free_pt);
n_pt[pid & pt_size].pt_pgrp = 0;
n_pt[pid & pt_size].pt_pid = 0;
next_free_pt = i | (pid & pt_size);
if (i == 0)
break;
}
/* Save old table size and switch tables */
tsz = pt_size * sizeof(struct pid_table);
n_pt = pid_table;
pid_table = new_pt;
pid_tbl_mask = new_pt_mask;
/*
* pid_max starts as PID_MAX (= 30000), once we have 16384
* allocated pids we need it to be larger!
*/
if (pid_tbl_mask > PID_MAX) {
pid_max = pid_tbl_mask * 2 + 1;
pid_alloc_lim |= pid_alloc_lim << 1;
} else
pid_alloc_lim <<= 1; /* doubles number of free slots... */
mutex_exit(&proc_lock);
/*
* Make sure that unlocked access to the old pid_table is complete
* and then free it.
*/
pserialize_perform(proc_psz);
kmem_free(n_pt, tsz);
out: /* Return with proc_lock held again. */
mutex_enter(&proc_lock);
}
struct proc *
proc_alloc(void)
{
struct proc *p;
p = pool_cache_get(proc_cache, PR_WAITOK);
p->p_stat = SIDL; /* protect against others */
proc_initspecific(p);
kdtrace_proc_ctor(NULL, p);
/*
* Allocate a placeholder in the pid_table. When we create the
* first LWP for this process, it will take ownership of the
* slot.
*/
if (__predict_false(proc_alloc_pid(p) == -1)) {
/* Allocating the PID failed; unwind. */
proc_finispecific(p);
proc_free_mem(p);
p = NULL;
}
return p;
}
/*
* proc_alloc_pid_slot: allocate PID and record the occcupant so that
* proc_find_raw() can find it by the PID.
*/
static pid_t __noinline
proc_alloc_pid_slot(struct proc *p, uintptr_t slot)
{
struct pid_table *pt;
pid_t pid;
int nxt;
KASSERT(mutex_owned(&proc_lock));
for (;;expand_pid_table()) {
if (__predict_false(pid_alloc_cnt >= pid_alloc_lim)) {
/* ensure pids cycle through 2000+ values */
continue;
}
/*
* The first user process *must* be given PID 1.
* it has already been reserved for us. This
* will be coming in from the proc_alloc() call
* above, and the entry will be usurped later when
* the first user LWP is created.
* XXX this is slightly gross.
*/
if (__predict_false(PT_RESERVED(pid_table[1].pt_slot) &&
p != &proc0)) {
KASSERT(PT_IS_PROC(slot));
pt = &pid_table[1];
pt->pt_slot = slot;
return 1;
}
pt = &pid_table[next_free_pt];
#ifdef DIAGNOSTIC
if (__predict_false(PT_VALID(pt->pt_slot) || pt->pt_pgrp))
panic("proc_alloc: slot busy");
#endif
nxt = PT_NEXT(pt->pt_slot);
if (nxt & pid_tbl_mask)
break;
/* Table full - expand (NB last entry not used....) */
}
/* pid is 'saved use count' + 'size' + entry */
pid = (nxt & ~pid_tbl_mask) + pid_tbl_mask + 1 + next_free_pt;
if ((uint)pid > (uint)pid_max)
pid &= pid_tbl_mask;
next_free_pt = nxt & pid_tbl_mask;
/* XXX For now. The pratical limit is much lower anyway. */
KASSERT(pid <= FUTEX_TID_MASK);
/* Grab table slot */
pt->pt_slot = slot;
KASSERT(pt->pt_pid == 0);
pt->pt_pid = pid;
pid_alloc_cnt++;
return pid;
}
pid_t
proc_alloc_pid(struct proc *p)
{
pid_t pid;
KASSERT((((uintptr_t)p) & PT_F_ALLBITS) == 0);
KASSERT(p->p_stat == SIDL);
mutex_enter(&proc_lock);
pid = proc_alloc_pid_slot(p, PT_SET_PROC(p));
if (pid != -1)
p->p_pid = pid;
mutex_exit(&proc_lock);
return pid;
}
pid_t
proc_alloc_lwpid(struct proc *p, struct lwp *l)
{
struct pid_table *pt;
pid_t pid;
KASSERT((((uintptr_t)l) & PT_F_ALLBITS) == 0);
KASSERT(l->l_proc == p);
KASSERT(l->l_stat == LSIDL);
/*
* For unlocked lookup in proc_find_lwp(), make sure l->l_proc
* is globally visible before the LWP becomes visible via the
* pid_table.
*/
#ifndef __HAVE_ATOMIC_AS_MEMBAR
membar_producer();
#endif
/*
* If the slot for p->p_pid currently points to the proc,
* then we should usurp this ID for the LWP. This happens
* at least once per process (for the first LWP), and can
* happen again if the first LWP for a process exits and
* before the process creates another.
*/
mutex_enter(&proc_lock);
pid = p->p_pid;
pt = &pid_table[pid & pid_tbl_mask];
KASSERT(pt->pt_pid == pid);
if (PT_IS_PROC(pt->pt_slot)) {
KASSERT(PT_GET_PROC(pt->pt_slot) == p);
l->l_lid = pid;
pt->pt_slot = PT_SET_LWP(l);
} else {
/* Need to allocate a new slot. */
pid = proc_alloc_pid_slot(p, PT_SET_LWP(l));
if (pid != -1)
l->l_lid = pid;
}
mutex_exit(&proc_lock);
return pid;
}
static void __noinline
proc_free_pid_internal(pid_t pid, uintptr_t type __diagused)
{
struct pid_table *pt;
pt = &pid_table[pid & pid_tbl_mask];
KASSERT(PT_GET_TYPE(pt->pt_slot) == type);
KASSERT(pt->pt_pid == pid);
/* save pid use count in slot */
pt->pt_slot = PT_SET_FREE(pid & ~pid_tbl_mask);
pt->pt_pid = 0;
if (pt->pt_pgrp == NULL) {
/* link last freed entry onto ours */
pid &= pid_tbl_mask;
pt = &pid_table[last_free_pt];
pt->pt_slot = PT_SET_FREE(PT_NEXT(pt->pt_slot) | pid);
pt->pt_pid = 0;
last_free_pt = pid;
pid_alloc_cnt--;
}
}
/*
* Free a process id - called from proc_free (in kern_exit.c)
*
* Called with the proc_lock held.
*/
void
proc_free_pid(pid_t pid)
{
KASSERT(mutex_owned(&proc_lock));
proc_free_pid_internal(pid, PT_F_PROC);
}
/*
* Free a process id used by an LWP. If this was the process's
* first LWP, we convert the slot to point to the process; the
* entry will get cleaned up later when the process finishes exiting.
*
* If not, then it's the same as proc_free_pid().
*/
void
proc_free_lwpid(struct proc *p, pid_t pid)
{
KASSERT(mutex_owned(&proc_lock));
if (__predict_true(p->p_pid == pid)) {
struct pid_table *pt;
pt = &pid_table[pid & pid_tbl_mask];
KASSERT(pt->pt_pid == pid);
KASSERT(PT_IS_LWP(pt->pt_slot));
KASSERT(PT_GET_LWP(pt->pt_slot)->l_proc == p);
pt->pt_slot = PT_SET_PROC(p);
return;
}
proc_free_pid_internal(pid, PT_F_LWP);
}
void
proc_free_mem(struct proc *p)
{
kdtrace_proc_dtor(NULL, p);
pool_cache_put(proc_cache, p);
}
/*
* proc_enterpgrp: move p to a new or existing process group (and session).
*
* If we are creating a new pgrp, the pgid should equal
* the calling process' pid.
* If is only valid to enter a process group that is in the session
* of the process.
* Also mksess should only be set if we are creating a process group
*
* Only called from sys_setsid, sys_setpgid and posix_spawn/spawn_return.
*/
int
proc_enterpgrp(struct proc *curp, pid_t pid, pid_t pgid, bool mksess)
{
struct pgrp *new_pgrp, *pgrp;
struct session *sess;
struct proc *p;
int rval;
pid_t pg_id = NO_PGID;
/* Allocate data areas we might need before doing any validity checks */
sess = mksess ? kmem_alloc(sizeof(*sess), KM_SLEEP) : NULL;
new_pgrp = kmem_alloc(sizeof(*new_pgrp), KM_SLEEP);
mutex_enter(&proc_lock);
rval = EPERM; /* most common error (to save typing) */
/* Check pgrp exists or can be created */
pgrp = pid_table[pgid & pid_tbl_mask].pt_pgrp;
if (pgrp != NULL && pgrp->pg_id != pgid)
goto done;
/* Can only set another process under restricted circumstances. */
if (pid != curp->p_pid) {
/* Must exist and be one of our children... */
p = proc_find_internal(pid, false);
if (p == NULL || !p_inferior(p, curp)) {
rval = ESRCH;
goto done;
}
/* ... in the same session... */
if (sess != NULL || p->p_session != curp->p_session)
goto done;
/* ... existing pgid must be in same session ... */
if (pgrp != NULL && pgrp->pg_session != p->p_session)
goto done;
/* ... and not done an exec. */
if (p->p_flag & PK_EXEC) {
rval = EACCES;
goto done;
}
} else {
/* ... setsid() cannot re-enter a pgrp */
if (mksess && (curp->p_pgid == curp->p_pid ||
pgrp_find(curp->p_pid)))
goto done;
p = curp;
}
/* Changing the process group/session of a session
leader is definitely off limits. */
if (SESS_LEADER(p)) {
if (sess == NULL && p->p_pgrp == pgrp)
/* unless it's a definite noop */
rval = 0;
goto done;
}
/* Can only create a process group with id of process */
if (pgrp == NULL && pgid != pid)
goto done;
/* Can only create a session if creating pgrp */
if (sess != NULL && pgrp != NULL)
goto done;
/* Check we allocated memory for a pgrp... */
if (pgrp == NULL && new_pgrp == NULL)
goto done;
/* Don't attach to 'zombie' pgrp */
if (pgrp != NULL && LIST_EMPTY(&pgrp->pg_members))
goto done;
/* Expect to succeed now */
rval = 0;
if (pgrp == p->p_pgrp)
/* nothing to do */
goto done;
/* Ok all setup, link up required structures */
if (pgrp == NULL) {
pgrp = new_pgrp;
new_pgrp = NULL;
if (sess != NULL) {
sess->s_sid = p->p_pid;
sess->s_leader = p;
sess->s_count = 1;
sess->s_ttyvp = NULL;
sess->s_ttyp = NULL;
sess->s_flags = p->p_session->s_flags & ~S_LOGIN_SET;
memcpy(sess->s_login, p->p_session->s_login,
sizeof(sess->s_login));
p->p_lflag &= ~PL_CONTROLT;
} else {
sess = p->p_pgrp->pg_session;
proc_sesshold(sess);
}
pgrp->pg_session = sess;
sess = NULL;
pgrp->pg_id = pgid;
LIST_INIT(&pgrp->pg_members);
#ifdef DIAGNOSTIC
if (__predict_false(pid_table[pgid & pid_tbl_mask].pt_pgrp))
panic("enterpgrp: pgrp table slot in use");
if (__predict_false(mksess && p != curp))
panic("enterpgrp: mksession and p != curproc");
#endif
pid_table[pgid & pid_tbl_mask].pt_pgrp = pgrp;
pgrp->pg_jobc = 0;
}
/*
* Adjust eligibility of affected pgrps to participate in job control.
* Increment eligibility counts before decrementing, otherwise we
* could reach 0 spuriously during the first call.
*/
fixjobc(p, pgrp, 1);
fixjobc(p, p->p_pgrp, 0);
/* Interlock with ttread(). */
mutex_spin_enter(&tty_lock);
/* Move process to requested group. */
LIST_REMOVE(p, p_pglist);
if (LIST_EMPTY(&p->p_pgrp->pg_members))
/* defer delete until we've dumped the lock */
pg_id = p->p_pgrp->pg_id;
p->p_pgrp = pgrp;
LIST_INSERT_HEAD(&pgrp->pg_members, p, p_pglist);
/* Done with the swap; we can release the tty mutex. */
mutex_spin_exit(&tty_lock);
done:
if (pg_id != NO_PGID) {
/* Releases proc_lock. */
pg_delete(pg_id);
} else {
mutex_exit(&proc_lock);
}
if (sess != NULL)
kmem_free(sess, sizeof(*sess));
if (new_pgrp != NULL)
kmem_free(new_pgrp, sizeof(*new_pgrp));
#ifdef DEBUG_PGRP
if (__predict_false(rval))
printf("enterpgrp(%d,%d,%d), curproc %d, rval %d\n",
pid, pgid, mksess, curp->p_pid, rval);
#endif
return rval;
}
/*
* proc_leavepgrp: remove a process from its process group.
* => must be called with the proc_lock held, which will be released;
*/
void
proc_leavepgrp(struct proc *p)
{
struct pgrp *pgrp;
KASSERT(mutex_owned(&proc_lock));
/* Interlock with ttread() */
mutex_spin_enter(&tty_lock);
pgrp = p->p_pgrp;
LIST_REMOVE(p, p_pglist);
p->p_pgrp = NULL;
mutex_spin_exit(&tty_lock);
if (LIST_EMPTY(&pgrp->pg_members)) {
/* Releases proc_lock. */
pg_delete(pgrp->pg_id);
} else {
mutex_exit(&proc_lock);
}
}
/*
* pg_remove: remove a process group from the table.
* => must be called with the proc_lock held;
* => returns process group to free;
*/
static struct pgrp *
pg_remove(pid_t pg_id)
{
struct pgrp *pgrp;
struct pid_table *pt;
KASSERT(mutex_owned(&proc_lock));
pt = &pid_table[pg_id & pid_tbl_mask];
pgrp = pt->pt_pgrp;
KASSERT(pgrp != NULL);
KASSERT(pgrp->pg_id == pg_id);
KASSERT(LIST_EMPTY(&pgrp->pg_members));
pt->pt_pgrp = NULL;
if (!PT_VALID(pt->pt_slot)) {
/* Orphaned pgrp, put slot onto free list. */
KASSERT((PT_NEXT(pt->pt_slot) & pid_tbl_mask) == 0);
pg_id &= pid_tbl_mask;
pt = &pid_table[last_free_pt];
pt->pt_slot = PT_SET_FREE(PT_NEXT(pt->pt_slot) | pg_id);
KASSERT(pt->pt_pid == 0);
last_free_pt = pg_id;
pid_alloc_cnt--;
}
return pgrp;
}
/*
* pg_delete: delete and free a process group.
* => must be called with the proc_lock held, which will be released.
*/
static void
pg_delete(pid_t pg_id)
{
struct pgrp *pg;
struct tty *ttyp;
struct session *ss;
KASSERT(mutex_owned(&proc_lock));
pg = pid_table[pg_id & pid_tbl_mask].pt_pgrp;
if (pg == NULL || pg->pg_id != pg_id || !LIST_EMPTY(&pg->pg_members)) {
mutex_exit(&proc_lock);
return;
}
ss = pg->pg_session;
/* Remove reference (if any) from tty to this process group */
mutex_spin_enter(&tty_lock);
ttyp = ss->s_ttyp;
if (ttyp != NULL && ttyp->t_pgrp == pg) {
ttyp->t_pgrp = NULL;
KASSERT(ttyp->t_session == ss);
}
mutex_spin_exit(&tty_lock);
/*
* The leading process group in a session is freed by proc_sessrele(),
* if last reference. It will also release the locks.
*/
pg = (ss->s_sid != pg->pg_id) ? pg_remove(pg_id) : NULL;
proc_sessrele(ss);
if (pg != NULL) {
/* Free it, if was not done above. */
kmem_free(pg, sizeof(struct pgrp));
}
}
/*
* Adjust pgrp jobc counters when specified process changes process group.
* We count the number of processes in each process group that "qualify"
* the group for terminal job control (those with a parent in a different
* process group of the same session). If that count reaches zero, the
* process group becomes orphaned. Check both the specified process'
* process group and that of its children.
* entering == 0 => p is leaving specified group.
* entering == 1 => p is entering specified group.
*
* Call with proc_lock held.
*/
void
fixjobc(struct proc *p, struct pgrp *pgrp, int entering)
{
struct pgrp *hispgrp;
struct session *mysession = pgrp->pg_session;
struct proc *child;
KASSERT(mutex_owned(&proc_lock));
/*
* Check p's parent to see whether p qualifies its own process
* group; if so, adjust count for p's process group.
*/
hispgrp = p->p_pptr->p_pgrp;
if (hispgrp != pgrp && hispgrp->pg_session == mysession) {
if (entering) {
pgrp->pg_jobc++;
p->p_lflag &= ~PL_ORPHANPG;
} else {
KASSERT(pgrp->pg_jobc > 0);
if (--pgrp->pg_jobc == 0)
orphanpg(pgrp);
}
}
/*
* Check this process' children to see whether they qualify
* their process groups; if so, adjust counts for children's
* process groups.
*/
LIST_FOREACH(child, &p->p_children, p_sibling) {
hispgrp = child->p_pgrp;
if (hispgrp != pgrp && hispgrp->pg_session == mysession &&
!P_ZOMBIE(child)) {
if (entering) {
child->p_lflag &= ~PL_ORPHANPG;
hispgrp->pg_jobc++;
} else {
KASSERT(hispgrp->pg_jobc > 0);
if (--hispgrp->pg_jobc == 0)
orphanpg(hispgrp);
}
}
}
}
/*
* A process group has become orphaned;
* if there are any stopped processes in the group,
* hang-up all process in that group.
*
* Call with proc_lock held.
*/
static void
orphanpg(struct pgrp *pg)
{
struct proc *p;
KASSERT(mutex_owned(&proc_lock));
LIST_FOREACH(p, &pg->pg_members, p_pglist) {
if (p->p_stat == SSTOP) {
p->p_lflag |= PL_ORPHANPG;
psignal(p, SIGHUP);
psignal(p, SIGCONT);
}
}
}
#ifdef DDB
#include <ddb/db_output.h>
void pidtbl_dump(void);
void
pidtbl_dump(void)
{
struct pid_table *pt;
struct proc *p;
struct pgrp *pgrp;
uintptr_t slot;
int id;
db_printf("pid table %p size %x, next %x, last %x\n",
pid_table, pid_tbl_mask+1,
next_free_pt, last_free_pt);
for (pt = pid_table, id = 0; id <= pid_tbl_mask; id++, pt++) {
slot = pt->pt_slot;
if (!PT_VALID(slot) && !pt->pt_pgrp)
continue;
if (PT_IS_LWP(slot)) {
p = PT_GET_LWP(slot)->l_proc;
} else if (PT_IS_PROC(slot)) {
p = PT_GET_PROC(slot);
} else {
p = NULL;
}
db_printf(" id %x: ", id);
if (p != NULL)
db_printf("slotpid %d proc %p id %d (0x%x) %s\n",
pt->pt_pid, p, p->p_pid, p->p_pid, p->p_comm);
else
db_printf("next %x use %x\n",
PT_NEXT(slot) & pid_tbl_mask,
PT_NEXT(slot) & ~pid_tbl_mask);
if ((pgrp = pt->pt_pgrp)) {
db_printf("\tsession %p, sid %d, count %d, login %s\n",
pgrp->pg_session, pgrp->pg_session->s_sid,
pgrp->pg_session->s_count,
pgrp->pg_session->s_login);
db_printf("\tpgrp %p, pg_id %d, pg_jobc %d, members %p\n",
pgrp, pgrp->pg_id, pgrp->pg_jobc,
LIST_FIRST(&pgrp->pg_members));
LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
db_printf("\t\tpid %d addr %p pgrp %p %s\n",
p->p_pid, p, p->p_pgrp, p->p_comm);
}
}
}
}
#endif /* DDB */
#ifdef KSTACK_CHECK_MAGIC
#define KSTACK_MAGIC 0xdeadbeaf
/* XXX should be per process basis? */
static int kstackleftmin = KSTACK_SIZE;
static int kstackleftthres = KSTACK_SIZE / 8;
void
kstack_setup_magic(const struct lwp *l)
{
uint32_t *ip;
uint32_t const *end;
KASSERT(l != NULL);
KASSERT(l != &lwp0);
/*
* fill all the stack with magic number
* so that later modification on it can be detected.
*/
ip = (uint32_t *)KSTACK_LOWEST_ADDR(l);
end = (uint32_t *)((char *)KSTACK_LOWEST_ADDR(l) + KSTACK_SIZE);
for (; ip < end; ip++) {
*ip = KSTACK_MAGIC;
}
}
void
kstack_check_magic(const struct lwp *l)
{
uint32_t const *ip, *end;
int stackleft;
KASSERT(l != NULL);
/* don't check proc0 */ /*XXX*/
if (l == &lwp0)
return;
#ifdef __MACHINE_STACK_GROWS_UP
/* stack grows upwards (eg. hppa) */
ip = (uint32_t *)((void *)KSTACK_LOWEST_ADDR(l) + KSTACK_SIZE);
end = (uint32_t *)KSTACK_LOWEST_ADDR(l);
for (ip--; ip >= end; ip--)
if (*ip != KSTACK_MAGIC)
break;
stackleft = (void *)KSTACK_LOWEST_ADDR(l) + KSTACK_SIZE - (void *)ip;
#else /* __MACHINE_STACK_GROWS_UP */
/* stack grows downwards (eg. i386) */
ip = (uint32_t *)KSTACK_LOWEST_ADDR(l);
end = (uint32_t *)((char *)KSTACK_LOWEST_ADDR(l) + KSTACK_SIZE);
for (; ip < end; ip++)
if (*ip != KSTACK_MAGIC)
break;
stackleft = ((const char *)ip) - (const char *)KSTACK_LOWEST_ADDR(l);
#endif /* __MACHINE_STACK_GROWS_UP */
if (kstackleftmin > stackleft) {
kstackleftmin = stackleft;
if (stackleft < kstackleftthres)
printf("warning: kernel stack left %d bytes"
"(pid %u:lid %u)\n", stackleft,
(u_int)l->l_proc->p_pid, (u_int)l->l_lid);
}
if (stackleft <= 0) {
panic("magic on the top of kernel stack changed for "
"pid %u, lid %u: maybe kernel stack overflow",
(u_int)l->l_proc->p_pid, (u_int)l->l_lid);
}
}
#endif /* KSTACK_CHECK_MAGIC */
int
proclist_foreach_call(struct proclist *list,
int (*callback)(struct proc *, void *arg), void *arg)
{
struct proc marker;
struct proc *p;
int ret = 0;
marker.p_flag = PK_MARKER;
mutex_enter(&proc_lock);
for (p = LIST_FIRST(list); ret == 0 && p != NULL;) {
if (p->p_flag & PK_MARKER) {
p = LIST_NEXT(p, p_list);
continue;
}
LIST_INSERT_AFTER(p, &marker, p_list);
ret = (*callback)(p, arg);
KASSERT(mutex_owned(&proc_lock));
p = LIST_NEXT(&marker, p_list);
LIST_REMOVE(&marker, p_list);
}
mutex_exit(&proc_lock);
return ret;
}
int
proc_vmspace_getref(struct proc *p, struct vmspace **vm)
{
/* XXXCDC: how should locking work here? */
/* curproc exception is for coredump. */
if ((p != curproc && (p->p_sflag & PS_WEXIT) != 0) ||
(p->p_vmspace->vm_refcnt < 1)) {
return EFAULT;
}
uvmspace_addref(p->p_vmspace);
*vm = p->p_vmspace;
return 0;
}
/*
* Acquire a write lock on the process credential.
*/
void
proc_crmod_enter(void)
{
struct lwp *l = curlwp;
struct proc *p = l->l_proc;
kauth_cred_t oc;
/* Reset what needs to be reset in plimit. */
if (p->p_limit->pl_corename != defcorename) {
lim_setcorename(p, defcorename, 0);
}
mutex_enter(p->p_lock);
/* Ensure the LWP cached credentials are up to date. */
if ((oc = l->l_cred) != p->p_cred) {
kauth_cred_hold(p->p_cred);
l->l_cred = p->p_cred;
kauth_cred_free(oc);
}
}
/*
* Set in a new process credential, and drop the write lock. The credential
* must have a reference already. Optionally, free a no-longer required
* credential. The scheduler also needs to inspect p_cred, so we also
* briefly acquire the sched state mutex.
*/
void
proc_crmod_leave(kauth_cred_t scred, kauth_cred_t fcred, bool sugid)
{
struct lwp *l = curlwp, *l2;
struct proc *p = l->l_proc;
kauth_cred_t oc;
KASSERT(mutex_owned(p->p_lock));
/* Is there a new credential to set in? */
if (scred != NULL) {
p->p_cred = scred;
LIST_FOREACH(l2, &p->p_lwps, l_sibling) {
if (l2 != l)
l2->l_prflag |= LPR_CRMOD;
}
/* Ensure the LWP cached credentials are up to date. */
if ((oc = l->l_cred) != scred) {
kauth_cred_hold(scred);
l->l_cred = scred;
}
} else
oc = NULL; /* XXXgcc */
if (sugid) {
/*
* Mark process as having changed credentials, stops
* tracing etc.
*/
p->p_flag |= PK_SUGID;
}
mutex_exit(p->p_lock);
/* If there is a credential to be released, free it now. */
if (fcred != NULL) {
KASSERT(scred != NULL);
kauth_cred_free(fcred);
if (oc != scred)
kauth_cred_free(oc);
}
}
/*
* proc_specific_key_create --
* Create a key for subsystem proc-specific data.
*/
int
proc_specific_key_create(specificdata_key_t *keyp, specificdata_dtor_t dtor)
{
return (specificdata_key_create(proc_specificdata_domain, keyp, dtor));
}
/*
* proc_specific_key_delete --
* Delete a key for subsystem proc-specific data.
*/
void
proc_specific_key_delete(specificdata_key_t key)
{
specificdata_key_delete(proc_specificdata_domain, key);
}
/*
* proc_initspecific --
* Initialize a proc's specificdata container.
*/
void
proc_initspecific(struct proc *p)
{
int error __diagused;
error = specificdata_init(proc_specificdata_domain, &p->p_specdataref);
KASSERT(error == 0);
}
/*
* proc_finispecific --
* Finalize a proc's specificdata container.
*/
void
proc_finispecific(struct proc *p)
{
specificdata_fini(proc_specificdata_domain, &p->p_specdataref);
}
/*
* proc_getspecific --
* Return proc-specific data corresponding to the specified key.
*/
void *
proc_getspecific(struct proc *p, specificdata_key_t key)
{
return (specificdata_getspecific(proc_specificdata_domain,
&p->p_specdataref, key));
}
/*
* proc_setspecific --
* Set proc-specific data corresponding to the specified key.
*/
void
proc_setspecific(struct proc *p, specificdata_key_t key, void *data)
{
specificdata_setspecific(proc_specificdata_domain,
&p->p_specdataref, key, data);
}
int
proc_uidmatch(kauth_cred_t cred, kauth_cred_t target)
{
int r = 0;
if (kauth_cred_getuid(cred) != kauth_cred_getuid(target) ||
kauth_cred_getuid(cred) != kauth_cred_getsvuid(target)) {
/*
* suid proc of ours or proc not ours
*/
r = EPERM;
} else if (kauth_cred_getgid(target) != kauth_cred_getsvgid(target)) {
/*
* sgid proc has sgid back to us temporarily
*/
r = EPERM;
} else {
/*
* our rgid must be in target's group list (ie,
* sub-processes started by a sgid process)
*/
int ismember = 0;
if (kauth_cred_ismember_gid(cred,
kauth_cred_getgid(target), &ismember) != 0 ||
!ismember)
r = EPERM;
}
return (r);
}
/*
* sysctl stuff
*/
#define KERN_PROCSLOP (5 * sizeof(struct kinfo_proc))
static const u_int sysctl_flagmap[] = {
PK_ADVLOCK, P_ADVLOCK,
PK_EXEC, P_EXEC,
PK_NOCLDWAIT, P_NOCLDWAIT,
PK_32, P_32,
PK_CLDSIGIGN, P_CLDSIGIGN,
PK_SUGID, P_SUGID,
0
};
static const u_int sysctl_sflagmap[] = {
PS_NOCLDSTOP, P_NOCLDSTOP,
PS_WEXIT, P_WEXIT,
PS_STOPFORK, P_STOPFORK,
PS_STOPEXEC, P_STOPEXEC,
PS_STOPEXIT, P_STOPEXIT,
0
};
static const u_int sysctl_slflagmap[] = {
PSL_TRACED, P_TRACED,
PSL_CHTRACED, P_CHTRACED,
PSL_SYSCALL, P_SYSCALL,
0
};
static const u_int sysctl_lflagmap[] = {
PL_CONTROLT, P_CONTROLT,
PL_PPWAIT, P_PPWAIT,
0
};
static const u_int sysctl_stflagmap[] = {
PST_PROFIL, P_PROFIL,
0
};
/* used by kern_lwp also */
const u_int sysctl_lwpflagmap[] = {
LW_SINTR, L_SINTR,
LW_SYSTEM, L_SYSTEM,
0
};
/*
* Find the most ``active'' lwp of a process and return it for ps display
* purposes
*/
static struct lwp *
proc_active_lwp(struct proc *p)
{
static const int ostat[] = {
0,
2, /* LSIDL */
6, /* LSRUN */
5, /* LSSLEEP */
4, /* LSSTOP */
0, /* LSZOMB */
1, /* LSDEAD */
7, /* LSONPROC */
3 /* LSSUSPENDED */
};
struct lwp *l, *lp = NULL;
LIST_FOREACH(l, &p->p_lwps, l_sibling) {
KASSERT(l->l_stat >= 0 && l->l_stat < __arraycount(ostat));
if (lp == NULL ||
ostat[l->l_stat] > ostat[lp->l_stat] ||
(ostat[l->l_stat] == ostat[lp->l_stat] &&
l->l_cpticks > lp->l_cpticks)) {
lp = l;
continue;
}
}
return lp;
}
static int
sysctl_doeproc(SYSCTLFN_ARGS)
{
union {
struct kinfo_proc kproc;
struct kinfo_proc2 kproc2;
} *kbuf;
struct proc *p, *next, *marker;
char *where, *dp;
int type, op, arg, error;
u_int elem_size, kelem_size, elem_count;
size_t buflen, needed;
bool match, zombie, mmmbrains;
const bool allowaddr = get_expose_address(curproc);
if (namelen == 1 && name[0] == CTL_QUERY)
return (sysctl_query(SYSCTLFN_CALL(rnode)));
dp = where = oldp;
buflen = where != NULL ? *oldlenp : 0;
error = 0;
needed = 0;
type = rnode->sysctl_num;
if (type == KERN_PROC) {
if (namelen == 0)
return EINVAL;
switch (op = name[0]) {
case KERN_PROC_ALL:
if (namelen != 1)
return EINVAL;
arg = 0;
break;
default:
if (namelen != 2)
return EINVAL;
arg = name[1];
break;
}
elem_count = 0; /* Hush little compiler, don't you cry */
kelem_size = elem_size = sizeof(kbuf->kproc);
} else {
if (namelen != 4)
return EINVAL;
op = name[0];
arg = name[1];
elem_size = name[2];
elem_count = name[3];
kelem_size = sizeof(kbuf->kproc2);
}
sysctl_unlock();
kbuf = kmem_zalloc(sizeof(*kbuf), KM_SLEEP);
marker = kmem_alloc(sizeof(*marker), KM_SLEEP);
marker->p_flag = PK_MARKER;
mutex_enter(&proc_lock);
/*
* Start with zombies to prevent reporting processes twice, in case they
* are dying and being moved from the list of alive processes to zombies.
*/
mmmbrains = true;
for (p = LIST_FIRST(&zombproc);; p = next) {
if (p == NULL) {
if (mmmbrains) {
p = LIST_FIRST(&allproc);
mmmbrains = false;
}
if (p == NULL)
break;
}
next = LIST_NEXT(p, p_list);
if ((p->p_flag & PK_MARKER) != 0)
continue;
/*
* Skip embryonic processes.
*/
if (p->p_stat == SIDL)
continue;
mutex_enter(p->p_lock);
error = kauth_authorize_process(l->l_cred,
KAUTH_PROCESS_CANSEE, p,
KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_EPROC), NULL, NULL);
if (error != 0) {
mutex_exit(p->p_lock);
continue;
}
/*
* Hande all the operations in one switch on the cost of
* algorithm complexity is on purpose. The win splitting this
* function into several similar copies makes maintenance burden
* burden, code grow and boost is neglible in practical systems.
*/
switch (op) {
case KERN_PROC_PID:
match = (p->p_pid == (pid_t)arg);
break;
case KERN_PROC_PGRP:
match = (p->p_pgrp->pg_id == (pid_t)arg);
break;
case KERN_PROC_SESSION:
match = (p->p_session->s_sid == (pid_t)arg);
break;
case KERN_PROC_TTY:
match = true;
if (arg == (int) KERN_PROC_TTY_REVOKE) {
if ((p->p_lflag & PL_CONTROLT) == 0 ||
p->p_session->s_ttyp == NULL ||
p->p_session->s_ttyvp != NULL) {
match = false;
}
} else if ((p->p_lflag & PL_CONTROLT) == 0 ||
p->p_session->s_ttyp == NULL) {
if ((dev_t)arg != KERN_PROC_TTY_NODEV) {
match = false;
}
} else if (p->p_session->s_ttyp->t_dev != (dev_t)arg) {
match = false;
}
break;
case KERN_PROC_UID:
match = (kauth_cred_geteuid(p->p_cred) == (uid_t)arg);
break;
case KERN_PROC_RUID:
match = (kauth_cred_getuid(p->p_cred) == (uid_t)arg);
break;
case KERN_PROC_GID:
match = (kauth_cred_getegid(p->p_cred) == (uid_t)arg);
break;
case KERN_PROC_RGID:
match = (kauth_cred_getgid(p->p_cred) == (uid_t)arg);
break;
case KERN_PROC_ALL:
match = true;
/* allow everything */
break;
default:
error = EINVAL;
mutex_exit(p->p_lock);
goto cleanup;
}
if (!match) {
mutex_exit(p->p_lock);
continue;
}
/*
* Grab a hold on the process.
*/
if (mmmbrains) {
zombie = true;
} else {
zombie = !rw_tryenter(&p->p_reflock, RW_READER);
}
if (zombie) {
LIST_INSERT_AFTER(p, marker, p_list);
}
if (buflen >= elem_size &&
(type == KERN_PROC || elem_count > 0)) {
ruspace(p); /* Update process vm resource use */
if (type == KERN_PROC) {
fill_proc(p, &kbuf->kproc.kp_proc, allowaddr);
fill_eproc(p, &kbuf->kproc.kp_eproc, zombie,
allowaddr);
} else {
fill_kproc2(p, &kbuf->kproc2, zombie,
allowaddr);
elem_count--;
}
mutex_exit(p->p_lock);
mutex_exit(&proc_lock);
/*
* Copy out elem_size, but not larger than kelem_size
*/
error = sysctl_copyout(l, kbuf, dp,
uimin(kelem_size, elem_size));
mutex_enter(&proc_lock);
if (error) {
goto bah;
}
dp += elem_size;
buflen -= elem_size;
} else {
mutex_exit(p->p_lock);
}
needed += elem_size;
/*
* Release reference to process.
*/
if (zombie) {
next = LIST_NEXT(marker, p_list);
LIST_REMOVE(marker, p_list);
} else {
rw_exit(&p->p_reflock);
next = LIST_NEXT(p, p_list);
}
/*
* Short-circuit break quickly!
*/
if (op == KERN_PROC_PID)
break;
}
mutex_exit(&proc_lock);
if (where != NULL) {
*oldlenp = dp - where;
if (needed > *oldlenp) {
error = ENOMEM;
goto out;
}
} else {
needed += KERN_PROCSLOP;
*oldlenp = needed;
}
kmem_free(kbuf, sizeof(*kbuf));
kmem_free(marker, sizeof(*marker));
sysctl_relock();
return 0;
bah:
if (zombie)
LIST_REMOVE(marker, p_list);
else
rw_exit(&p->p_reflock);
cleanup:
mutex_exit(&proc_lock);
out:
kmem_free(kbuf, sizeof(*kbuf));
kmem_free(marker, sizeof(*marker));
sysctl_relock();
return error;
}
int
copyin_psstrings(struct proc *p, struct ps_strings *arginfo)
{
#if !defined(_RUMPKERNEL)
int retval;
if (p->p_flag & PK_32) {
MODULE_HOOK_CALL(kern_proc32_copyin_hook, (p, arginfo),
enosys(), retval);
return retval;
}
#endif /* !defined(_RUMPKERNEL) */
return copyin_proc(p, (void *)p->p_psstrp, arginfo, sizeof(*arginfo));
}
static int
copy_procargs_sysctl_cb(void *cookie_, const void *src, size_t off, size_t len)
{
void **cookie = cookie_;
struct lwp *l = cookie[0];
char *dst = cookie[1];
return sysctl_copyout(l, src, dst + off, len);
}
/*
* sysctl helper routine for kern.proc_args pseudo-subtree.
*/
static int
sysctl_kern_proc_args(SYSCTLFN_ARGS)
{
struct ps_strings pss;
struct proc *p;
pid_t pid;
int type, error;
void *cookie[2];
if (namelen == 1 && name[0] == CTL_QUERY)
return (sysctl_query(SYSCTLFN_CALL(rnode)));
if (newp != NULL || namelen != 2)
return (EINVAL);
pid = name[0];
type = name[1];
switch (type) {
case KERN_PROC_PATHNAME:
sysctl_unlock();
error = fill_pathname(l, pid, oldp, oldlenp);
sysctl_relock();
return error;
case KERN_PROC_CWD:
sysctl_unlock();
error = fill_cwd(l, pid, oldp, oldlenp);
sysctl_relock();
return error;
case KERN_PROC_ARGV:
case KERN_PROC_NARGV:
case KERN_PROC_ENV:
case KERN_PROC_NENV:
/* ok */
break;
default:
return (EINVAL);
}
sysctl_unlock();
/* check pid */
mutex_enter(&proc_lock);
if ((p = proc_find(pid)) == NULL) {
error = EINVAL;
goto out_locked;
}
mutex_enter(p->p_lock);
/* Check permission. */
if (type == KERN_PROC_ARGV || type == KERN_PROC_NARGV)
error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_CANSEE,
p, KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_ARGS), NULL, NULL);
else if (type == KERN_PROC_ENV || type == KERN_PROC_NENV)
error = kauth_authorize_process(l->l_cred, KAUTH_PROCESS_CANSEE,
p, KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_ENV), NULL, NULL);
else
error = EINVAL; /* XXXGCC */
if (error) {
mutex_exit(p->p_lock);
goto out_locked;
}
if (oldp == NULL) {
if (type == KERN_PROC_NARGV || type == KERN_PROC_NENV)
*oldlenp = sizeof (int);
else
*oldlenp = ARG_MAX; /* XXX XXX XXX */
error = 0;
mutex_exit(p->p_lock);
goto out_locked;
}
/*
* Zombies don't have a stack, so we can't read their psstrings.
* System processes also don't have a user stack.
*/
if (P_ZOMBIE(p) || (p->p_flag & PK_SYSTEM) != 0) {
error = EINVAL;
mutex_exit(p->p_lock);
goto out_locked;
}
error = rw_tryenter(&p->p_reflock, RW_READER) ? 0 : EBUSY;
mutex_exit(p->p_lock);
if (error) {
goto out_locked;
}
mutex_exit(&proc_lock);
if (type == KERN_PROC_NARGV || type == KERN_PROC_NENV) {
int value;
if ((error = copyin_psstrings(p, &pss)) == 0) {
if (type == KERN_PROC_NARGV)
value = pss.ps_nargvstr;
else
value = pss.ps_nenvstr;
error = sysctl_copyout(l, &value, oldp, sizeof(value));
*oldlenp = sizeof(value);
}
} else {
cookie[0] = l;
cookie[1] = oldp;
error = copy_procargs(p, type, oldlenp,
copy_procargs_sysctl_cb, cookie);
}
rw_exit(&p->p_reflock);
sysctl_relock();
return error;
out_locked:
mutex_exit(&proc_lock);
sysctl_relock();
return error;
}
int
copy_procargs(struct proc *p, int oid, size_t *limit,
int (*cb)(void *, const void *, size_t, size_t), void *cookie)
{
struct ps_strings pss;
size_t len, i, loaded, entry_len;
struct uio auio;
struct iovec aiov;
int error, argvlen;
char *arg;
char **argv;
vaddr_t user_argv;
struct vmspace *vmspace;
/*
* Allocate a temporary buffer to hold the argument vector and
* the arguments themselve.
*/
arg = kmem_alloc(PAGE_SIZE, KM_SLEEP);
argv = kmem_alloc(PAGE_SIZE, KM_SLEEP);
/*
* Lock the process down in memory.
*/
vmspace = p->p_vmspace;
uvmspace_addref(vmspace);
/*
* Read in the ps_strings structure.
*/
if ((error = copyin_psstrings(p, &pss)) != 0)
goto done;
/*
* Now read the address of the argument vector.
*/
switch (oid) {
case KERN_PROC_ARGV:
user_argv = (uintptr_t)pss.ps_argvstr;
argvlen = pss.ps_nargvstr;
break;
case KERN_PROC_ENV:
user_argv = (uintptr_t)pss.ps_envstr;
argvlen = pss.ps_nenvstr;
break;
default:
error = EINVAL;
goto done;
}
if (argvlen < 0) {
error = EIO;
goto done;
}
/*
* Now copy each string.
*/
len = 0; /* bytes written to user buffer */
loaded = 0; /* bytes from argv already processed */
i = 0; /* To make compiler happy */
entry_len = PROC_PTRSZ(p);
for (; argvlen; --argvlen) {
int finished = 0;
vaddr_t base;
size_t xlen;
int j;
if (loaded == 0) {
size_t rem = entry_len * argvlen;
loaded = MIN(rem, PAGE_SIZE);
error = copyin_vmspace(vmspace,
(const void *)user_argv, argv, loaded);
if (error)
break;
user_argv += loaded;
i = 0;
}
#if !defined(_RUMPKERNEL)
if (p->p_flag & PK_32)
MODULE_HOOK_CALL(kern_proc32_base_hook,
(argv, i++), 0, base);
else
#endif /* !defined(_RUMPKERNEL) */
base = (vaddr_t)argv[i++];
loaded -= entry_len;
/*
* The program has messed around with its arguments,
* possibly deleting some, and replacing them with
* NULL's. Treat this as the last argument and not
* a failure.
*/
if (base == 0)
break;
while (!finished) {
xlen = PAGE_SIZE - (base & PAGE_MASK);
aiov.iov_base = arg;
aiov.iov_len = PAGE_SIZE;
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_offset = base;
auio.uio_resid = xlen;
auio.uio_rw = UIO_READ;
UIO_SETUP_SYSSPACE(&auio);
error = uvm_io(&vmspace->vm_map, &auio, 0);
if (error)
goto done;
/* Look for the end of the string */
for (j = 0; j < xlen; j++) {
if (arg[j] == '\0') {
xlen = j + 1;
finished = 1;
break;
}
}
/* Check for user buffer overflow */
if (len + xlen > *limit) {
finished = 1;
if (len > *limit)
xlen = 0;
else
xlen = *limit - len;
}
/* Copyout the page */
error = (*cb)(cookie, arg, len, xlen);
if (error)
goto done;
len += xlen;
base += xlen;
}
}
*limit = len;
done:
kmem_free(argv, PAGE_SIZE);
kmem_free(arg, PAGE_SIZE);
uvmspace_free(vmspace);
return error;
}
/*
* Fill in a proc structure for the specified process.
*/
static void
fill_proc(const struct proc *psrc, struct proc *p, bool allowaddr)
{
COND_SET_VALUE(p->p_list, psrc->p_list, allowaddr);
COND_SET_VALUE(p->p_auxlock, psrc->p_auxlock, allowaddr);
COND_SET_VALUE(p->p_lock, psrc->p_lock, allowaddr);
COND_SET_VALUE(p->p_stmutex, psrc->p_stmutex, allowaddr);
COND_SET_VALUE(p->p_reflock, psrc->p_reflock, allowaddr);
COND_SET_VALUE(p->p_waitcv, psrc->p_waitcv, allowaddr);
COND_SET_VALUE(p->p_lwpcv, psrc->p_lwpcv, allowaddr);
COND_SET_VALUE(p->p_cred, psrc->p_cred, allowaddr);
COND_SET_VALUE(p->p_fd, psrc->p_fd, allowaddr);
COND_SET_VALUE(p->p_cwdi, psrc->p_cwdi, allowaddr);
COND_SET_VALUE(p->p_stats, psrc->p_stats, allowaddr);
COND_SET_VALUE(p->p_limit, psrc->p_limit, allowaddr);
COND_SET_VALUE(p->p_vmspace, psrc->p_vmspace, allowaddr);
COND_SET_VALUE(p->p_sigacts, psrc->p_sigacts, allowaddr);
COND_SET_VALUE(p->p_aio, psrc->p_aio, allowaddr);
p->p_mqueue_cnt = psrc->p_mqueue_cnt;
COND_SET_VALUE(p->p_specdataref, psrc->p_specdataref, allowaddr);
p->p_exitsig = psrc->p_exitsig;
p->p_flag = psrc->p_flag;
p->p_sflag = psrc->p_sflag;
p->p_slflag = psrc->p_slflag;
p->p_lflag = psrc->p_lflag;
p->p_stflag = psrc->p_stflag;
p->p_stat = psrc->p_stat;
p->p_trace_enabled = psrc->p_trace_enabled;
p->p_pid = psrc->p_pid;
COND_SET_VALUE(p->p_pglist, psrc->p_pglist, allowaddr);
COND_SET_VALUE(p->p_pptr, psrc->p_pptr, allowaddr);
COND_SET_VALUE(p->p_sibling, psrc->p_sibling, allowaddr);
COND_SET_VALUE(p->p_children, psrc->p_children, allowaddr);
COND_SET_VALUE(p->p_lwps, psrc->p_lwps, allowaddr);
COND_SET_VALUE(p->p_raslist, psrc->p_raslist, allowaddr);
p->p_nlwps = psrc->p_nlwps;
p->p_nzlwps = psrc->p_nzlwps;
p->p_nrlwps = psrc->p_nrlwps;
p->p_nlwpwait = psrc->p_nlwpwait;
p->p_ndlwps = psrc->p_ndlwps;
p->p_nstopchild = psrc->p_nstopchild;
p->p_waited = psrc->p_waited;
COND_SET_VALUE(p->p_zomblwp, psrc->p_zomblwp, allowaddr);
COND_SET_VALUE(p->p_vforklwp, psrc->p_vforklwp, allowaddr);
COND_SET_VALUE(p->p_sched_info, psrc->p_sched_info, allowaddr);
p->p_estcpu = psrc->p_estcpu;
p->p_estcpu_inherited = psrc->p_estcpu_inherited;
p->p_forktime = psrc->p_forktime;
p->p_pctcpu = psrc->p_pctcpu;
COND_SET_VALUE(p->p_opptr, psrc->p_opptr, allowaddr);
COND_SET_VALUE(p->p_timers, psrc->p_timers, allowaddr);
p->p_rtime = psrc->p_rtime;
p->p_uticks = psrc->p_uticks;
p->p_sticks = psrc->p_sticks;
p->p_iticks = psrc->p_iticks;
p->p_xutime = psrc->p_xutime;
p->p_xstime = psrc->p_xstime;
p->p_traceflag = psrc->p_traceflag;
COND_SET_VALUE(p->p_tracep, psrc->p_tracep, allowaddr);
COND_SET_VALUE(p->p_textvp, psrc->p_textvp, allowaddr);
COND_SET_VALUE(p->p_emul, psrc->p_emul, allowaddr);
COND_SET_VALUE(p->p_emuldata, psrc->p_emuldata, allowaddr);
COND_SET_VALUE(p->p_execsw, psrc->p_execsw, allowaddr);
COND_SET_VALUE(p->p_klist, psrc->p_klist, allowaddr);
COND_SET_VALUE(p->p_sigwaiters, psrc->p_sigwaiters, allowaddr);
COND_SET_VALUE(p->p_sigpend, psrc->p_sigpend, allowaddr);
COND_SET_VALUE(p->p_lwpctl, psrc->p_lwpctl, allowaddr);
p->p_ppid = psrc->p_ppid;
p->p_oppid = psrc->p_oppid;
COND_SET_VALUE(p->p_path, psrc->p_path, allowaddr);
COND_SET_VALUE(p->p_sigctx, psrc->p_sigctx, allowaddr);
p->p_nice = psrc->p_nice;
memcpy(p->p_comm, psrc->p_comm, sizeof(p->p_comm));
COND_SET_VALUE(p->p_pgrp, psrc->p_pgrp, allowaddr);
COND_SET_VALUE(p->p_psstrp, psrc->p_psstrp, allowaddr);
p->p_pax = psrc->p_pax;
p->p_xexit = psrc->p_xexit;
p->p_xsig = psrc->p_xsig;
p->p_acflag = psrc->p_acflag;
COND_SET_VALUE(p->p_md, psrc->p_md, allowaddr);
p->p_stackbase = psrc->p_stackbase;
COND_SET_VALUE(p->p_dtrace, psrc->p_dtrace, allowaddr);
}
/*
* Fill in an eproc structure for the specified process.
*/
void
fill_eproc(struct proc *p, struct eproc *ep, bool zombie, bool allowaddr)
{
struct tty *tp;
struct lwp *l;
KASSERT(mutex_owned(&proc_lock));
KASSERT(mutex_owned(p->p_lock));
COND_SET_VALUE(ep->e_paddr, p, allowaddr);
COND_SET_VALUE(ep->e_sess, p->p_session, allowaddr);
if (p->p_cred) {
kauth_cred_topcred(p->p_cred, &ep->e_pcred);
kauth_cred_toucred(p->p_cred, &ep->e_ucred);
}
if (p->p_stat != SIDL && !P_ZOMBIE(p) && !zombie) {
struct vmspace *vm = p->p_vmspace;
ep->e_vm.vm_rssize = vm_resident_count(vm);
ep->e_vm.vm_tsize = vm->vm_tsize;
ep->e_vm.vm_dsize = vm->vm_dsize;
ep->e_vm.vm_ssize = vm->vm_ssize;
ep->e_vm.vm_map.size = vm->vm_map.size;
/* Pick the primary (first) LWP */
l = proc_active_lwp(p);
KASSERT(l != NULL);
lwp_lock(l);
if (l->l_wchan)
strncpy(ep->e_wmesg, l->l_wmesg, WMESGLEN);
lwp_unlock(l);
}
ep->e_ppid = p->p_ppid;
if (p->p_pgrp && p->p_session) {
ep->e_pgid = p->p_pgrp->pg_id;
ep->e_jobc = p->p_pgrp->pg_jobc;
ep->e_sid = p->p_session->s_sid;
if ((p->p_lflag & PL_CONTROLT) &&
(tp = p->p_session->s_ttyp)) {
ep->e_tdev = tp->t_dev;
ep->e_tpgid = tp->t_pgrp ? tp->t_pgrp->pg_id : NO_PGID;
COND_SET_VALUE(ep->e_tsess, tp->t_session, allowaddr);
} else
ep->e_tdev = (uint32_t)NODEV;
ep->e_flag = p->p_session->s_ttyvp ? EPROC_CTTY : 0;
if (SESS_LEADER(p))
ep->e_flag |= EPROC_SLEADER;
strncpy(ep->e_login, p->p_session->s_login, MAXLOGNAME);
}
ep->e_xsize = ep->e_xrssize = 0;
ep->e_xccount = ep->e_xswrss = 0;
}
/*
* Fill in a kinfo_proc2 structure for the specified process.
*/
void
fill_kproc2(struct proc *p, struct kinfo_proc2 *ki, bool zombie, bool allowaddr)
{
struct tty *tp;
struct lwp *l, *l2;
struct timeval ut, st, rt;
sigset_t ss1, ss2;
struct rusage ru;
struct vmspace *vm;
KASSERT(mutex_owned(&proc_lock));
KASSERT(mutex_owned(p->p_lock));
sigemptyset(&ss1);
sigemptyset(&ss2);
COND_SET_VALUE(ki->p_paddr, PTRTOUINT64(p), allowaddr);
COND_SET_VALUE(ki->p_fd, PTRTOUINT64(p->p_fd), allowaddr);
COND_SET_VALUE(ki->p_cwdi, PTRTOUINT64(p->p_cwdi), allowaddr);
COND_SET_VALUE(ki->p_stats, PTRTOUINT64(p->p_stats), allowaddr);
COND_SET_VALUE(ki->p_limit, PTRTOUINT64(p->p_limit), allowaddr);
COND_SET_VALUE(ki->p_vmspace, PTRTOUINT64(p->p_vmspace), allowaddr);
COND_SET_VALUE(ki->p_sigacts, PTRTOUINT64(p->p_sigacts), allowaddr);
COND_SET_VALUE(ki->p_sess, PTRTOUINT64(p->p_session), allowaddr);
ki->p_tsess = 0; /* may be changed if controlling tty below */
COND_SET_VALUE(ki->p_ru, PTRTOUINT64(&p->p_stats->p_ru), allowaddr);
ki->p_eflag = 0;
ki->p_exitsig = p->p_exitsig;
ki->p_flag = L_INMEM; /* Process never swapped out */
ki->p_flag |= sysctl_map_flags(sysctl_flagmap, p->p_flag);
ki->p_flag |= sysctl_map_flags(sysctl_sflagmap, p->p_sflag);
ki->p_flag |= sysctl_map_flags(sysctl_slflagmap, p->p_slflag);
ki->p_flag |= sysctl_map_flags(sysctl_lflagmap, p->p_lflag);
ki->p_flag |= sysctl_map_flags(sysctl_stflagmap, p->p_stflag);
ki->p_pid = p->p_pid;
ki->p_ppid = p->p_ppid;
ki->p_uid = kauth_cred_geteuid(p->p_cred);
ki->p_ruid = kauth_cred_getuid(p->p_cred);
ki->p_gid = kauth_cred_getegid(p->p_cred);
ki->p_rgid = kauth_cred_getgid(p->p_cred);
ki->p_svuid = kauth_cred_getsvuid(p->p_cred);
ki->p_svgid = kauth_cred_getsvgid(p->p_cred);
ki->p_ngroups = kauth_cred_ngroups(p->p_cred);
kauth_cred_getgroups(p->p_cred, ki->p_groups,
uimin(ki->p_ngroups, sizeof(ki->p_groups) / sizeof(ki->p_groups[0])),
UIO_SYSSPACE);
ki->p_uticks = p->p_uticks;
ki->p_sticks = p->p_sticks;
ki->p_iticks = p->p_iticks;
ki->p_tpgid = NO_PGID; /* may be changed if controlling tty below */
COND_SET_VALUE(ki->p_tracep, PTRTOUINT64(p->p_tracep), allowaddr);
ki->p_traceflag = p->p_traceflag;
memcpy(&ki->p_sigignore, &p->p_sigctx.ps_sigignore,sizeof(ki_sigset_t));
memcpy(&ki->p_sigcatch, &p->p_sigctx.ps_sigcatch, sizeof(ki_sigset_t));
ki->p_cpticks = 0;
ki->p_pctcpu = p->p_pctcpu;
ki->p_estcpu = 0;
ki->p_stat = p->p_stat; /* Will likely be overridden by LWP status */
ki->p_realstat = p->p_stat;
ki->p_nice = p->p_nice;
ki->p_xstat = P_WAITSTATUS(p);
ki->p_acflag = p->p_acflag;
strncpy(ki->p_comm, p->p_comm,
uimin(sizeof(ki->p_comm), sizeof(p->p_comm)));
strncpy(ki->p_ename, p->p_emul->e_name, sizeof(ki->p_ename));
ki->p_nlwps = p->p_nlwps;
ki->p_realflag = ki->p_flag;
if (p->p_stat != SIDL && !P_ZOMBIE(p) && !zombie) {
vm = p->p_vmspace;
ki->p_vm_rssize = vm_resident_count(vm);
ki->p_vm_tsize = vm->vm_tsize;
ki->p_vm_dsize = vm->vm_dsize;
ki->p_vm_ssize = vm->vm_ssize;
ki->p_vm_vsize = atop(vm->vm_map.size);
/*
* Since the stack is initially mapped mostly with
* PROT_NONE and grown as needed, adjust the "mapped size"
* to skip the unused stack portion.
*/
ki->p_vm_msize =
atop(vm->vm_map.size) - vm->vm_issize + vm->vm_ssize;
/* Pick the primary (first) LWP */
l = proc_active_lwp(p);
KASSERT(l != NULL);
lwp_lock(l);
ki->p_nrlwps = p->p_nrlwps;
ki->p_forw = 0;
ki->p_back = 0;
COND_SET_VALUE(ki->p_addr, PTRTOUINT64(l->l_addr), allowaddr);
ki->p_stat = l->l_stat;
ki->p_flag |= sysctl_map_flags(sysctl_lwpflagmap, l->l_flag);
ki->p_swtime = l->l_swtime;
ki->p_slptime = l->l_slptime;
if (l->l_stat == LSONPROC)
ki->p_schedflags = l->l_cpu->ci_schedstate.spc_flags;
else
ki->p_schedflags = 0;
ki->p_priority = lwp_eprio(l);
ki->p_usrpri = l->l_priority;
if (l->l_wchan)
strncpy(ki->p_wmesg, l->l_wmesg, sizeof(ki->p_wmesg));
COND_SET_VALUE(ki->p_wchan, PTRTOUINT64(l->l_wchan), allowaddr);
ki->p_cpuid = cpu_index(l->l_cpu);
lwp_unlock(l);
LIST_FOREACH(l, &p->p_lwps, l_sibling) {
/* This is hardly correct, but... */
sigplusset(&l->l_sigpend.sp_set, &ss1);
sigplusset(&l->l_sigmask, &ss2);
ki->p_cpticks += l->l_cpticks;
ki->p_pctcpu += l->l_pctcpu;
ki->p_estcpu += l->l_estcpu;
}
}
sigplusset(&p->p_sigpend.sp_set, &ss1);
memcpy(&ki->p_siglist, &ss1, sizeof(ki_sigset_t));
memcpy(&ki->p_sigmask, &ss2, sizeof(ki_sigset_t));
if (p->p_session != NULL) {
ki->p_sid = p->p_session->s_sid;
ki->p__pgid = p->p_pgrp->pg_id;
if (p->p_session->s_ttyvp)
ki->p_eflag |= EPROC_CTTY;
if (SESS_LEADER(p))
ki->p_eflag |= EPROC_SLEADER;
strncpy(ki->p_login, p->p_session->s_login,
uimin(sizeof ki->p_login - 1, sizeof p->p_session->s_login));
ki->p_jobc = p->p_pgrp->pg_jobc;
if ((p->p_lflag & PL_CONTROLT) && (tp = p->p_session->s_ttyp)) {
ki->p_tdev = tp->t_dev;
ki->p_tpgid = tp->t_pgrp ? tp->t_pgrp->pg_id : NO_PGID;
COND_SET_VALUE(ki->p_tsess, PTRTOUINT64(tp->t_session),
allowaddr);
} else {
ki->p_tdev = (int32_t)NODEV;
}
}
if (!P_ZOMBIE(p) && !zombie) {
ki->p_uvalid = 1;
ki->p_ustart_sec = p->p_stats->p_start.tv_sec;
ki->p_ustart_usec = p->p_stats->p_start.tv_usec;
calcru(p, &ut, &st, NULL, &rt);
ki->p_rtime_sec = rt.tv_sec;
ki->p_rtime_usec = rt.tv_usec;
ki->p_uutime_sec = ut.tv_sec;
ki->p_uutime_usec = ut.tv_usec;
ki->p_ustime_sec = st.tv_sec;
ki->p_ustime_usec = st.tv_usec;
memcpy(&ru, &p->p_stats->p_ru, sizeof(ru));
ki->p_uru_nvcsw = 0;
ki->p_uru_nivcsw = 0;
LIST_FOREACH(l2, &p->p_lwps, l_sibling) {
ki->p_uru_nvcsw += (l2->l_ncsw - l2->l_nivcsw);
ki->p_uru_nivcsw += l2->l_nivcsw;
ruadd(&ru, &l2->l_ru);
}
ki->p_uru_maxrss = ru.ru_maxrss;
ki->p_uru_ixrss = ru.ru_ixrss;
ki->p_uru_idrss = ru.ru_idrss;
ki->p_uru_isrss = ru.ru_isrss;
ki->p_uru_minflt = ru.ru_minflt;
ki->p_uru_majflt = ru.ru_majflt;
ki->p_uru_nswap = ru.ru_nswap;
ki->p_uru_inblock = ru.ru_inblock;
ki->p_uru_oublock = ru.ru_oublock;
ki->p_uru_msgsnd = ru.ru_msgsnd;
ki->p_uru_msgrcv = ru.ru_msgrcv;
ki->p_uru_nsignals = ru.ru_nsignals;
timeradd(&p->p_stats->p_cru.ru_utime,
&p->p_stats->p_cru.ru_stime, &ut);
ki->p_uctime_sec = ut.tv_sec;
ki->p_uctime_usec = ut.tv_usec;
}
}
int
proc_find_locked(struct lwp *l, struct proc **p, pid_t pid)
{
int error;
mutex_enter(&proc_lock);
if (pid == -1)
*p = l->l_proc;
else
*p = proc_find(pid);
if (*p == NULL) {
if (pid != -1)
mutex_exit(&proc_lock);
return ESRCH;
}
if (pid != -1)
mutex_enter((*p)->p_lock);
mutex_exit(&proc_lock);
error = kauth_authorize_process(l->l_cred,
KAUTH_PROCESS_CANSEE, *p,
KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_ENTRY), NULL, NULL);
if (error) {
if (pid != -1)
mutex_exit((*p)->p_lock);
}
return error;
}
static int
fill_pathname(struct lwp *l, pid_t pid, void *oldp, size_t *oldlenp)
{
int error;
struct proc *p;
if ((error = proc_find_locked(l, &p, pid)) != 0)
return error;
if (p->p_path == NULL) {
if (pid != -1)
mutex_exit(p->p_lock);
return ENOENT;
}
size_t len = strlen(p->p_path) + 1;
if (oldp != NULL) {
size_t copylen = uimin(len, *oldlenp);
error = sysctl_copyout(l, p->p_path, oldp, copylen);
if (error == 0 && *oldlenp < len)
error = ENOSPC;
}
*oldlenp = len;
if (pid != -1)
mutex_exit(p->p_lock);
return error;
}
static int
fill_cwd(struct lwp *l, pid_t pid, void *oldp, size_t *oldlenp)
{
int error;
struct proc *p;
char *path;
char *bp, *bend;
struct cwdinfo *cwdi;
struct vnode *vp;
size_t len, lenused;
if ((error = proc_find_locked(l, &p, pid)) != 0)
return error;
len = MAXPATHLEN * 4;
path = kmem_alloc(len, KM_SLEEP);
bp = &path[len];
bend = bp;
*(--bp) = '\0';
cwdi = p->p_cwdi;
rw_enter(&cwdi->cwdi_lock, RW_READER);
vp = cwdi->cwdi_cdir;
error = getcwd_common(vp, NULL, &bp, path, len/2, 0, l);
rw_exit(&cwdi->cwdi_lock);
if (error)
goto out;
lenused = bend - bp;
if (oldp != NULL) {
size_t copylen = uimin(lenused, *oldlenp);
error = sysctl_copyout(l, bp, oldp, copylen);
if (error == 0 && *oldlenp < lenused)
error = ENOSPC;
}
*oldlenp = lenused;
out:
if (pid != -1)
mutex_exit(p->p_lock);
kmem_free(path, len);
return error;
}
int
proc_getauxv(struct proc *p, void **buf, size_t *len)
{
struct ps_strings pss;
int error;
void *uauxv, *kauxv;
size_t size;
if ((error = copyin_psstrings(p, &pss)) != 0)
return error;
if (pss.ps_envstr == NULL)
return EIO;
size = p->p_execsw->es_arglen;
if (size == 0)
return EIO;
size_t ptrsz = PROC_PTRSZ(p);
uauxv = (void *)((char *)pss.ps_envstr + (pss.ps_nenvstr + 1) * ptrsz);
kauxv = kmem_alloc(size, KM_SLEEP);
error = copyin_proc(p, uauxv, kauxv, size);
if (error) {
kmem_free(kauxv, size);
return error;
}
*buf = kauxv;
*len = size;
return 0;
}
static int
sysctl_security_expose_address(SYSCTLFN_ARGS)
{
int expose_address, error;
struct sysctlnode node;
node = *rnode;
node.sysctl_data = &expose_address;
expose_address = *(int *)rnode->sysctl_data;
error = sysctl_lookup(SYSCTLFN_CALL(&node));
if (error || newp == NULL)
return error;
if (kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_KERNADDR,
0, NULL, NULL, NULL))
return EPERM;
switch (expose_address) {
case 0:
case 1:
case 2:
break;
default:
return EINVAL;
}
*(int *)rnode->sysctl_data = expose_address;
return 0;
}
bool
get_expose_address(struct proc *p)
{
/* allow only if sysctl variable is set or privileged */
return kauth_authorize_process(kauth_cred_get(), KAUTH_PROCESS_CANSEE,
p, KAUTH_ARG(KAUTH_REQ_PROCESS_CANSEE_KPTR), NULL, NULL) == 0;
}
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