1 /* $NetBSD: procfs_ctl.c,v 1.45 2008/04/24 18:39:25 ad Exp $ */
5 * The Regents of the University of California. All rights reserved.
7 * This code is derived from software contributed to Berkeley by
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * @(#)procfs_ctl.c 8.4 (Berkeley) 6/15/94
38 * Copyright (c) 1993 Jan-Simon Pendry
40 * This code is derived from software contributed to Berkeley by
43 * Redistribution and use in source and binary forms, with or without
44 * modification, are permitted provided that the following conditions
46 * 1. Redistributions of source code must retain the above copyright
47 * notice, this list of conditions and the following disclaimer.
48 * 2. Redistributions in binary form must reproduce the above copyright
49 * notice, this list of conditions and the following disclaimer in the
50 * documentation and/or other materials provided with the distribution.
51 * 3. All advertising materials mentioning features or use of this software
52 * must display the following acknowledgement:
53 * This product includes software developed by the University of
54 * California, Berkeley and its contributors.
55 * 4. Neither the name of the University nor the names of its contributors
56 * may be used to endorse or promote products derived from this software
57 * without specific prior written permission.
59 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
60 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
61 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
62 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
63 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
64 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
65 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
66 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
67 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
68 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
71 * @(#)procfs_ctl.c 8.4 (Berkeley) 6/15/94
74 #include <sys/cdefs.h>
75 __KERNEL_RCSID(0, "$NetBSD: procfs_ctl.c,v 1.45 2008/04/24 18:39:25 ad Exp $");
77 #include <sys/param.h>
78 #include <sys/systm.h>
80 #include <sys/kernel.h>
82 #include <sys/vnode.h>
83 #include <sys/ioctl.h>
85 #include <sys/resource.h>
86 #include <sys/resourcevar.h>
87 #include <sys/signalvar.h>
88 #include <sys/kauth.h>
90 #include <uvm/uvm_extern.h>
92 #include <miscfs/procfs/procfs.h>
94 #define PROCFS_CTL_ATTACH 1
95 #define PROCFS_CTL_DETACH 2
96 #define PROCFS_CTL_STEP 3
97 #define PROCFS_CTL_RUN 4
98 #define PROCFS_CTL_WAIT 5
100 static const vfs_namemap_t ctlnames
[] = {
101 /* special /proc commands */
102 { "attach", PROCFS_CTL_ATTACH
},
103 { "detach", PROCFS_CTL_DETACH
},
104 { "step", PROCFS_CTL_STEP
},
105 { "run", PROCFS_CTL_RUN
},
106 { "wait", PROCFS_CTL_WAIT
},
110 static const vfs_namemap_t signames
[] = {
111 /* regular signal names */
112 { "hup", SIGHUP
}, { "int", SIGINT
},
113 { "quit", SIGQUIT
}, { "ill", SIGILL
},
114 { "trap", SIGTRAP
}, { "abrt", SIGABRT
},
115 { "iot", SIGIOT
}, { "emt", SIGEMT
},
116 { "fpe", SIGFPE
}, { "kill", SIGKILL
},
117 { "bus", SIGBUS
}, { "segv", SIGSEGV
},
118 { "sys", SIGSYS
}, { "pipe", SIGPIPE
},
119 { "alrm", SIGALRM
}, { "term", SIGTERM
},
120 { "urg", SIGURG
}, { "stop", SIGSTOP
},
121 { "tstp", SIGTSTP
}, { "cont", SIGCONT
},
122 { "chld", SIGCHLD
}, { "ttin", SIGTTIN
},
123 { "ttou", SIGTTOU
}, { "io", SIGIO
},
124 { "xcpu", SIGXCPU
}, { "xfsz", SIGXFSZ
},
125 { "vtalrm", SIGVTALRM
}, { "prof", SIGPROF
},
126 { "winch", SIGWINCH
}, { "info", SIGINFO
},
127 { "usr1", SIGUSR1
}, { "usr2", SIGUSR2
},
131 static int procfs_control(struct lwp
*, struct lwp
*, int, int,
135 procfs_control(struct lwp
*curl
, struct lwp
*l
, int op
, int sig
, struct pfsnode
*pfs
)
137 struct proc
*curp
= curl
->l_proc
;
138 struct proc
*p
= l
->l_proc
;
141 mutex_enter(proc_lock
);
142 mutex_enter(p
->p_lock
);
146 * Attach - attaches the target process for debugging
147 * by the calling process.
149 case PROCFS_CTL_ATTACH
:
151 * You can't attach to a process if:
152 * (1) it's the process that's doing the attaching,
154 if (p
->p_pid
== curp
->p_pid
) {
160 * (2) it's already being traced, or
162 if (ISSET(p
->p_slflag
, PSL_TRACED
)) {
168 * (3) the security model prevents it.
170 if ((error
= kauth_authorize_process(curl
->l_cred
,
171 KAUTH_PROCESS_PROCFS
, p
, pfs
,
172 KAUTH_ARG(KAUTH_REQ_PROCESS_PROCFS_CTL
), NULL
)) != 0)
178 * Target process must be stopped, owned by (curp) and
179 * be set up for tracing (PSL_TRACED flag set).
180 * Allow DETACH to take place at any time for sanity.
181 * Allow WAIT any time, of course.
183 * Note that the semantics of DETACH are different here
186 case PROCFS_CTL_DETACH
:
187 case PROCFS_CTL_WAIT
:
189 * You can't do what you want to the process if:
190 * (1) It's not being traced at all,
192 if (!ISSET(p
->p_slflag
, PSL_TRACED
)) {
198 * (2) it's being traced by ptrace(2) (which has
199 * different signal delivery semantics), or
201 if (!ISSET(p
->p_slflag
, PSL_FSTRACE
)) {
207 * (3) it's not being traced by _you_.
209 if (p
->p_pptr
!= curp
)
216 * You can't do what you want to the process if:
217 * (1) It's not being traced at all,
219 if (!ISSET(p
->p_slflag
, PSL_TRACED
)) {
225 * (2) it's being traced by ptrace(2) (which has
226 * different signal delivery semantics),
228 if (!ISSET(p
->p_slflag
, PSL_FSTRACE
)) {
234 * (3) it's not being traced by _you_, or
236 if (p
->p_pptr
!= curp
) {
242 * (4) it's not currently stopped.
244 if (p
->p_stat
!= SSTOP
|| !p
->p_waited
/* XXXSMP */)
251 mutex_exit(p
->p_lock
);
252 mutex_exit(proc_lock
);
256 /* Do single-step fixup if needed. */
260 case PROCFS_CTL_ATTACH
:
262 * Go ahead and set the trace flag.
263 * Save the old parent (it's reset in
264 * _DETACH, and also in kern_exit.c:wait4()
265 * Reparent the process so that the tracing
266 * proc gets to see all the action.
269 SET(p
->p_slflag
, PSL_TRACED
|PSL_FSTRACE
);
270 p
->p_opptr
= p
->p_pptr
;
271 if (p
->p_pptr
!= curp
) {
272 if (p
->p_pptr
->p_lock
< p
->p_lock
) {
273 if (!mutex_tryenter(p
->p_pptr
->p_lock
)) {
274 mutex_exit(p
->p_lock
);
275 mutex_enter(p
->p_pptr
->p_lock
);
277 } else if (p
->p_pptr
->p_lock
> p
->p_lock
) {
278 mutex_enter(p
->p_pptr
->p_lock
);
280 p
->p_pptr
->p_slflag
|= PSL_CHTRACED
;
281 proc_reparent(p
, curp
);
282 if (p
->p_pptr
->p_lock
!= p
->p_lock
)
283 mutex_exit(p
->p_pptr
->p_lock
);
289 case PROCFS_CTL_STEP
:
291 * Step. Let the target process execute a single instruction.
295 case PROCFS_CTL_DETACH
:
299 error
= process_sstep(l
, op
== PROCFS_CTL_STEP
);
305 if (op
== PROCFS_CTL_DETACH
) {
306 /* give process back to original parent */
307 if (p
->p_opptr
!= p
->p_pptr
) {
308 struct proc
*pp
= p
->p_opptr
;
309 proc_reparent(p
, pp
? pp
: initproc
);
312 /* not being traced any more */
314 CLR(p
->p_slflag
, PSL_TRACED
|PSL_FSTRACE
);
315 p
->p_waited
= 0; /* XXXSMP */
319 /* Finally, deliver the requested signal (or none). */
321 if (l
->l_stat
== LSSTOP
) {
323 /* setrunnable() will release the lock. */
328 mutex_exit(p
->p_lock
);
330 mutex_enter(p
->p_lock
);
333 mutex_exit(p
->p_lock
);
334 mutex_exit(proc_lock
);
337 case PROCFS_CTL_WAIT
:
338 mutex_exit(p
->p_lock
);
339 mutex_exit(proc_lock
);
342 * Wait for the target process to stop.
343 * XXXSMP WTF is this?
345 while (l
->l_stat
!= LSSTOP
&& P_ZOMBIE(p
)) {
346 error
= tsleep(l
, PWAIT
|PCATCH
, "procfsx", hz
);
358 mutex_exit(p
->p_lock
);
359 mutex_exit(proc_lock
);
371 struct proc
*p
= l
->l_proc
;
372 char msg
[PROCFS_CTLLEN
+1];
373 const vfs_namemap_t
*nm
;
377 if (uio
->uio_rw
!= UIO_WRITE
)
380 xlen
= PROCFS_CTLLEN
;
381 error
= vfs_getuserstr(uio
, msg
, &xlen
);
386 * Map signal names into signal generation
387 * or debug control. Unknown commands and/or signals
390 * Sending a signal while the process is being debugged
391 * also has the side effect of letting the target continue
392 * to run. There is no way to single-step a signal delivery.
396 nm
= vfs_findname(ctlnames
, msg
, xlen
);
398 error
= procfs_control(curl
, l
, nm
->nm_val
, 0, pfs
);
400 nm
= vfs_findname(signames
, msg
, xlen
);
402 if (ISSET(p
->p_slflag
, PSL_TRACED
) &&
404 error
= procfs_control(curl
, l
, PROCFS_CTL_RUN
,
407 psignal(p
, nm
->nm_val
);