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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/kernel/ptrace.c | |
3 | * | |
4 | * (C) Copyright 1999 Linus Torvalds | |
5 | * | |
6 | * Common interfaces for "ptrace()" which we do not want | |
7 | * to continually duplicate across every architecture. | |
8 | */ | |
9 | ||
c59ede7b | 10 | #include <linux/capability.h> |
9984de1a | 11 | #include <linux/export.h> |
1da177e4 | 12 | #include <linux/sched.h> |
6e84f315 | 13 | #include <linux/sched/mm.h> |
f7ccbae4 | 14 | #include <linux/sched/coredump.h> |
29930025 | 15 | #include <linux/sched/task.h> |
1da177e4 LT |
16 | #include <linux/errno.h> |
17 | #include <linux/mm.h> | |
18 | #include <linux/highmem.h> | |
19 | #include <linux/pagemap.h> | |
1da177e4 LT |
20 | #include <linux/ptrace.h> |
21 | #include <linux/security.h> | |
7ed20e1a | 22 | #include <linux/signal.h> |
a27bb332 | 23 | #include <linux/uio.h> |
a5cb013d | 24 | #include <linux/audit.h> |
b488893a | 25 | #include <linux/pid_namespace.h> |
f17d30a8 | 26 | #include <linux/syscalls.h> |
3a709703 | 27 | #include <linux/uaccess.h> |
2225a122 | 28 | #include <linux/regset.h> |
bf26c018 | 29 | #include <linux/hw_breakpoint.h> |
f701e5b7 | 30 | #include <linux/cn_proc.h> |
84c751bd | 31 | #include <linux/compat.h> |
fcfc2aa0 | 32 | #include <linux/sched/signal.h> |
1da177e4 | 33 | |
84d77d3f EB |
34 | /* |
35 | * Access another process' address space via ptrace. | |
36 | * Source/target buffer must be kernel space, | |
37 | * Do not walk the page table directly, use get_user_pages | |
38 | */ | |
39 | int ptrace_access_vm(struct task_struct *tsk, unsigned long addr, | |
40 | void *buf, int len, unsigned int gup_flags) | |
41 | { | |
42 | struct mm_struct *mm; | |
43 | int ret; | |
44 | ||
45 | mm = get_task_mm(tsk); | |
46 | if (!mm) | |
47 | return 0; | |
48 | ||
49 | if (!tsk->ptrace || | |
50 | (current != tsk->parent) || | |
51 | ((get_dumpable(mm) != SUID_DUMP_USER) && | |
52 | !ptracer_capable(tsk, mm->user_ns))) { | |
53 | mmput(mm); | |
54 | return 0; | |
55 | } | |
56 | ||
57 | ret = __access_remote_vm(tsk, mm, addr, buf, len, gup_flags); | |
58 | mmput(mm); | |
59 | ||
60 | return ret; | |
61 | } | |
62 | ||
bf53de90 | 63 | |
c70d9d80 EB |
64 | void __ptrace_link(struct task_struct *child, struct task_struct *new_parent, |
65 | const struct cred *ptracer_cred) | |
66 | { | |
67 | BUG_ON(!list_empty(&child->ptrace_entry)); | |
68 | list_add(&child->ptrace_entry, &new_parent->ptraced); | |
69 | child->parent = new_parent; | |
70 | child->ptracer_cred = get_cred(ptracer_cred); | |
71 | } | |
72 | ||
1da177e4 LT |
73 | /* |
74 | * ptrace a task: make the debugger its new parent and | |
75 | * move it to the ptrace list. | |
76 | * | |
77 | * Must be called with the tasklist lock write-held. | |
78 | */ | |
c70d9d80 | 79 | static void ptrace_link(struct task_struct *child, struct task_struct *new_parent) |
1da177e4 | 80 | { |
64b875f7 | 81 | rcu_read_lock(); |
c70d9d80 | 82 | __ptrace_link(child, new_parent, __task_cred(new_parent)); |
64b875f7 | 83 | rcu_read_unlock(); |
1da177e4 | 84 | } |
3a709703 | 85 | |
e3bd058f TH |
86 | /** |
87 | * __ptrace_unlink - unlink ptracee and restore its execution state | |
88 | * @child: ptracee to be unlinked | |
1da177e4 | 89 | * |
0e9f0a4a TH |
90 | * Remove @child from the ptrace list, move it back to the original parent, |
91 | * and restore the execution state so that it conforms to the group stop | |
92 | * state. | |
93 | * | |
94 | * Unlinking can happen via two paths - explicit PTRACE_DETACH or ptracer | |
95 | * exiting. For PTRACE_DETACH, unless the ptracee has been killed between | |
96 | * ptrace_check_attach() and here, it's guaranteed to be in TASK_TRACED. | |
97 | * If the ptracer is exiting, the ptracee can be in any state. | |
98 | * | |
99 | * After detach, the ptracee should be in a state which conforms to the | |
100 | * group stop. If the group is stopped or in the process of stopping, the | |
101 | * ptracee should be put into TASK_STOPPED; otherwise, it should be woken | |
102 | * up from TASK_TRACED. | |
103 | * | |
104 | * If the ptracee is in TASK_TRACED and needs to be moved to TASK_STOPPED, | |
105 | * it goes through TRACED -> RUNNING -> STOPPED transition which is similar | |
106 | * to but in the opposite direction of what happens while attaching to a | |
107 | * stopped task. However, in this direction, the intermediate RUNNING | |
108 | * state is not hidden even from the current ptracer and if it immediately | |
109 | * re-attaches and performs a WNOHANG wait(2), it may fail. | |
e3bd058f TH |
110 | * |
111 | * CONTEXT: | |
112 | * write_lock_irq(tasklist_lock) | |
1da177e4 | 113 | */ |
36c8b586 | 114 | void __ptrace_unlink(struct task_struct *child) |
1da177e4 | 115 | { |
64b875f7 | 116 | const struct cred *old_cred; |
5ecfbae0 ON |
117 | BUG_ON(!child->ptrace); |
118 | ||
0a5bf409 AN |
119 | clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
120 | ||
f470021a RM |
121 | child->parent = child->real_parent; |
122 | list_del_init(&child->ptrace_entry); | |
64b875f7 EB |
123 | old_cred = child->ptracer_cred; |
124 | child->ptracer_cred = NULL; | |
125 | put_cred(old_cred); | |
1da177e4 | 126 | |
1da177e4 | 127 | spin_lock(&child->sighand->siglock); |
1333ab03 | 128 | child->ptrace = 0; |
73ddff2b TH |
129 | /* |
130 | * Clear all pending traps and TRAPPING. TRAPPING should be | |
131 | * cleared regardless of JOBCTL_STOP_PENDING. Do it explicitly. | |
132 | */ | |
133 | task_clear_jobctl_pending(child, JOBCTL_TRAP_MASK); | |
134 | task_clear_jobctl_trapping(child); | |
135 | ||
0e9f0a4a | 136 | /* |
a8f072c1 | 137 | * Reinstate JOBCTL_STOP_PENDING if group stop is in effect and |
0e9f0a4a TH |
138 | * @child isn't dead. |
139 | */ | |
140 | if (!(child->flags & PF_EXITING) && | |
141 | (child->signal->flags & SIGNAL_STOP_STOPPED || | |
8a88951b | 142 | child->signal->group_stop_count)) { |
a8f072c1 | 143 | child->jobctl |= JOBCTL_STOP_PENDING; |
0e9f0a4a | 144 | |
8a88951b ON |
145 | /* |
146 | * This is only possible if this thread was cloned by the | |
147 | * traced task running in the stopped group, set the signal | |
148 | * for the future reports. | |
149 | * FIXME: we should change ptrace_init_task() to handle this | |
150 | * case. | |
151 | */ | |
152 | if (!(child->jobctl & JOBCTL_STOP_SIGMASK)) | |
153 | child->jobctl |= SIGSTOP; | |
154 | } | |
155 | ||
0e9f0a4a TH |
156 | /* |
157 | * If transition to TASK_STOPPED is pending or in TASK_TRACED, kick | |
158 | * @child in the butt. Note that @resume should be used iff @child | |
159 | * is in TASK_TRACED; otherwise, we might unduly disrupt | |
160 | * TASK_KILLABLE sleeps. | |
161 | */ | |
a8f072c1 | 162 | if (child->jobctl & JOBCTL_STOP_PENDING || task_is_traced(child)) |
910ffdb1 | 163 | ptrace_signal_wake_up(child, true); |
0e9f0a4a | 164 | |
1da177e4 | 165 | spin_unlock(&child->sighand->siglock); |
1da177e4 LT |
166 | } |
167 | ||
9899d11f ON |
168 | /* Ensure that nothing can wake it up, even SIGKILL */ |
169 | static bool ptrace_freeze_traced(struct task_struct *task) | |
170 | { | |
171 | bool ret = false; | |
172 | ||
173 | /* Lockless, nobody but us can set this flag */ | |
174 | if (task->jobctl & JOBCTL_LISTENING) | |
175 | return ret; | |
176 | ||
177 | spin_lock_irq(&task->sighand->siglock); | |
178 | if (task_is_traced(task) && !__fatal_signal_pending(task)) { | |
179 | task->state = __TASK_TRACED; | |
180 | ret = true; | |
181 | } | |
182 | spin_unlock_irq(&task->sighand->siglock); | |
183 | ||
184 | return ret; | |
185 | } | |
186 | ||
187 | static void ptrace_unfreeze_traced(struct task_struct *task) | |
188 | { | |
189 | if (task->state != __TASK_TRACED) | |
190 | return; | |
191 | ||
192 | WARN_ON(!task->ptrace || task->parent != current); | |
193 | ||
5402e97a | 194 | /* |
195 | * PTRACE_LISTEN can allow ptrace_trap_notify to wake us up remotely. | |
196 | * Recheck state under the lock to close this race. | |
197 | */ | |
9899d11f | 198 | spin_lock_irq(&task->sighand->siglock); |
5402e97a | 199 | if (task->state == __TASK_TRACED) { |
200 | if (__fatal_signal_pending(task)) | |
201 | wake_up_state(task, __TASK_TRACED); | |
202 | else | |
203 | task->state = TASK_TRACED; | |
204 | } | |
9899d11f ON |
205 | spin_unlock_irq(&task->sighand->siglock); |
206 | } | |
207 | ||
755e276b TH |
208 | /** |
209 | * ptrace_check_attach - check whether ptracee is ready for ptrace operation | |
210 | * @child: ptracee to check for | |
211 | * @ignore_state: don't check whether @child is currently %TASK_TRACED | |
212 | * | |
213 | * Check whether @child is being ptraced by %current and ready for further | |
214 | * ptrace operations. If @ignore_state is %false, @child also should be in | |
215 | * %TASK_TRACED state and on return the child is guaranteed to be traced | |
216 | * and not executing. If @ignore_state is %true, @child can be in any | |
217 | * state. | |
218 | * | |
219 | * CONTEXT: | |
220 | * Grabs and releases tasklist_lock and @child->sighand->siglock. | |
221 | * | |
222 | * RETURNS: | |
223 | * 0 on success, -ESRCH if %child is not ready. | |
1da177e4 | 224 | */ |
edea0d03 | 225 | static int ptrace_check_attach(struct task_struct *child, bool ignore_state) |
1da177e4 LT |
226 | { |
227 | int ret = -ESRCH; | |
228 | ||
229 | /* | |
230 | * We take the read lock around doing both checks to close a | |
231 | * possible race where someone else was tracing our child and | |
232 | * detached between these two checks. After this locked check, | |
233 | * we are sure that this is our traced child and that can only | |
234 | * be changed by us so it's not changing right after this. | |
235 | */ | |
236 | read_lock(&tasklist_lock); | |
9899d11f ON |
237 | if (child->ptrace && child->parent == current) { |
238 | WARN_ON(child->state == __TASK_TRACED); | |
c0c0b649 ON |
239 | /* |
240 | * child->sighand can't be NULL, release_task() | |
241 | * does ptrace_unlink() before __exit_signal(). | |
242 | */ | |
9899d11f | 243 | if (ignore_state || ptrace_freeze_traced(child)) |
321fb561 | 244 | ret = 0; |
1da177e4 LT |
245 | } |
246 | read_unlock(&tasklist_lock); | |
247 | ||
9899d11f ON |
248 | if (!ret && !ignore_state) { |
249 | if (!wait_task_inactive(child, __TASK_TRACED)) { | |
250 | /* | |
251 | * This can only happen if may_ptrace_stop() fails and | |
252 | * ptrace_stop() changes ->state back to TASK_RUNNING, | |
253 | * so we should not worry about leaking __TASK_TRACED. | |
254 | */ | |
255 | WARN_ON(child->state == __TASK_TRACED); | |
256 | ret = -ESRCH; | |
257 | } | |
258 | } | |
1da177e4 | 259 | |
1da177e4 LT |
260 | return ret; |
261 | } | |
262 | ||
69f594a3 EP |
263 | static int ptrace_has_cap(struct user_namespace *ns, unsigned int mode) |
264 | { | |
265 | if (mode & PTRACE_MODE_NOAUDIT) | |
266 | return has_ns_capability_noaudit(current, ns, CAP_SYS_PTRACE); | |
267 | else | |
268 | return has_ns_capability(current, ns, CAP_SYS_PTRACE); | |
269 | } | |
270 | ||
9f99798f TH |
271 | /* Returns 0 on success, -errno on denial. */ |
272 | static int __ptrace_may_access(struct task_struct *task, unsigned int mode) | |
ab8d11be | 273 | { |
c69e8d9c | 274 | const struct cred *cred = current_cred(), *tcred; |
bfedb589 | 275 | struct mm_struct *mm; |
caaee623 JH |
276 | kuid_t caller_uid; |
277 | kgid_t caller_gid; | |
278 | ||
279 | if (!(mode & PTRACE_MODE_FSCREDS) == !(mode & PTRACE_MODE_REALCREDS)) { | |
280 | WARN(1, "denying ptrace access check without PTRACE_MODE_*CREDS\n"); | |
281 | return -EPERM; | |
282 | } | |
b6dff3ec | 283 | |
df26c40e EB |
284 | /* May we inspect the given task? |
285 | * This check is used both for attaching with ptrace | |
286 | * and for allowing access to sensitive information in /proc. | |
287 | * | |
288 | * ptrace_attach denies several cases that /proc allows | |
289 | * because setting up the necessary parent/child relationship | |
290 | * or halting the specified task is impossible. | |
291 | */ | |
caaee623 | 292 | |
df26c40e | 293 | /* Don't let security modules deny introspection */ |
73af963f | 294 | if (same_thread_group(task, current)) |
df26c40e | 295 | return 0; |
c69e8d9c | 296 | rcu_read_lock(); |
caaee623 JH |
297 | if (mode & PTRACE_MODE_FSCREDS) { |
298 | caller_uid = cred->fsuid; | |
299 | caller_gid = cred->fsgid; | |
300 | } else { | |
301 | /* | |
302 | * Using the euid would make more sense here, but something | |
303 | * in userland might rely on the old behavior, and this | |
304 | * shouldn't be a security problem since | |
305 | * PTRACE_MODE_REALCREDS implies that the caller explicitly | |
306 | * used a syscall that requests access to another process | |
307 | * (and not a filesystem syscall to procfs). | |
308 | */ | |
309 | caller_uid = cred->uid; | |
310 | caller_gid = cred->gid; | |
311 | } | |
c69e8d9c | 312 | tcred = __task_cred(task); |
caaee623 JH |
313 | if (uid_eq(caller_uid, tcred->euid) && |
314 | uid_eq(caller_uid, tcred->suid) && | |
315 | uid_eq(caller_uid, tcred->uid) && | |
316 | gid_eq(caller_gid, tcred->egid) && | |
317 | gid_eq(caller_gid, tcred->sgid) && | |
318 | gid_eq(caller_gid, tcred->gid)) | |
8409cca7 | 319 | goto ok; |
c4a4d603 | 320 | if (ptrace_has_cap(tcred->user_ns, mode)) |
8409cca7 SH |
321 | goto ok; |
322 | rcu_read_unlock(); | |
323 | return -EPERM; | |
324 | ok: | |
c69e8d9c | 325 | rcu_read_unlock(); |
bfedb589 EB |
326 | mm = task->mm; |
327 | if (mm && | |
328 | ((get_dumpable(mm) != SUID_DUMP_USER) && | |
329 | !ptrace_has_cap(mm->user_ns, mode))) | |
330 | return -EPERM; | |
ab8d11be | 331 | |
9e48858f | 332 | return security_ptrace_access_check(task, mode); |
ab8d11be MS |
333 | } |
334 | ||
006ebb40 | 335 | bool ptrace_may_access(struct task_struct *task, unsigned int mode) |
ab8d11be MS |
336 | { |
337 | int err; | |
338 | task_lock(task); | |
006ebb40 | 339 | err = __ptrace_may_access(task, mode); |
ab8d11be | 340 | task_unlock(task); |
3a709703 | 341 | return !err; |
ab8d11be MS |
342 | } |
343 | ||
3544d72a | 344 | static int ptrace_attach(struct task_struct *task, long request, |
aa9147c9 | 345 | unsigned long addr, |
3544d72a | 346 | unsigned long flags) |
1da177e4 | 347 | { |
3544d72a | 348 | bool seize = (request == PTRACE_SEIZE); |
1da177e4 | 349 | int retval; |
f5b40e36 | 350 | |
3544d72a | 351 | retval = -EIO; |
aa9147c9 DV |
352 | if (seize) { |
353 | if (addr != 0) | |
354 | goto out; | |
aa9147c9 DV |
355 | if (flags & ~(unsigned long)PTRACE_O_MASK) |
356 | goto out; | |
357 | flags = PT_PTRACED | PT_SEIZED | (flags << PT_OPT_FLAG_SHIFT); | |
358 | } else { | |
359 | flags = PT_PTRACED; | |
360 | } | |
3544d72a | 361 | |
a5cb013d AV |
362 | audit_ptrace(task); |
363 | ||
1da177e4 | 364 | retval = -EPERM; |
b79b7ba9 ON |
365 | if (unlikely(task->flags & PF_KTHREAD)) |
366 | goto out; | |
bac0abd6 | 367 | if (same_thread_group(task, current)) |
f5b40e36 LT |
368 | goto out; |
369 | ||
f2f0b00a ON |
370 | /* |
371 | * Protect exec's credential calculations against our interference; | |
86b6c1f3 | 372 | * SUID, SGID and LSM creds get determined differently |
5e751e99 | 373 | * under ptrace. |
d84f4f99 | 374 | */ |
793285fc | 375 | retval = -ERESTARTNOINTR; |
9b1bf12d | 376 | if (mutex_lock_interruptible(&task->signal->cred_guard_mutex)) |
d84f4f99 | 377 | goto out; |
f5b40e36 | 378 | |
4b105cbb | 379 | task_lock(task); |
caaee623 | 380 | retval = __ptrace_may_access(task, PTRACE_MODE_ATTACH_REALCREDS); |
4b105cbb | 381 | task_unlock(task); |
1da177e4 | 382 | if (retval) |
4b105cbb | 383 | goto unlock_creds; |
1da177e4 | 384 | |
4b105cbb | 385 | write_lock_irq(&tasklist_lock); |
b79b7ba9 ON |
386 | retval = -EPERM; |
387 | if (unlikely(task->exit_state)) | |
4b105cbb | 388 | goto unlock_tasklist; |
f2f0b00a | 389 | if (task->ptrace) |
4b105cbb | 390 | goto unlock_tasklist; |
b79b7ba9 | 391 | |
3544d72a | 392 | if (seize) |
aa9147c9 | 393 | flags |= PT_SEIZED; |
aa9147c9 | 394 | task->ptrace = flags; |
1da177e4 | 395 | |
c70d9d80 | 396 | ptrace_link(task, current); |
3544d72a TH |
397 | |
398 | /* SEIZE doesn't trap tracee on attach */ | |
399 | if (!seize) | |
079b22dc | 400 | send_sig_info(SIGSTOP, SEND_SIG_PRIV, task); |
b79b7ba9 | 401 | |
d79fdd6d TH |
402 | spin_lock(&task->sighand->siglock); |
403 | ||
404 | /* | |
73ddff2b | 405 | * If the task is already STOPPED, set JOBCTL_TRAP_STOP and |
d79fdd6d TH |
406 | * TRAPPING, and kick it so that it transits to TRACED. TRAPPING |
407 | * will be cleared if the child completes the transition or any | |
408 | * event which clears the group stop states happens. We'll wait | |
409 | * for the transition to complete before returning from this | |
410 | * function. | |
411 | * | |
412 | * This hides STOPPED -> RUNNING -> TRACED transition from the | |
413 | * attaching thread but a different thread in the same group can | |
414 | * still observe the transient RUNNING state. IOW, if another | |
415 | * thread's WNOHANG wait(2) on the stopped tracee races against | |
416 | * ATTACH, the wait(2) may fail due to the transient RUNNING. | |
417 | * | |
418 | * The following task_is_stopped() test is safe as both transitions | |
419 | * in and out of STOPPED are protected by siglock. | |
420 | */ | |
7dd3db54 | 421 | if (task_is_stopped(task) && |
73ddff2b | 422 | task_set_jobctl_pending(task, JOBCTL_TRAP_STOP | JOBCTL_TRAPPING)) |
910ffdb1 | 423 | signal_wake_up_state(task, __TASK_STOPPED); |
d79fdd6d TH |
424 | |
425 | spin_unlock(&task->sighand->siglock); | |
426 | ||
b79b7ba9 | 427 | retval = 0; |
4b105cbb ON |
428 | unlock_tasklist: |
429 | write_unlock_irq(&tasklist_lock); | |
430 | unlock_creds: | |
9b1bf12d | 431 | mutex_unlock(&task->signal->cred_guard_mutex); |
f5b40e36 | 432 | out: |
f701e5b7 | 433 | if (!retval) { |
7c3b00e0 ON |
434 | /* |
435 | * We do not bother to change retval or clear JOBCTL_TRAPPING | |
436 | * if wait_on_bit() was interrupted by SIGKILL. The tracer will | |
437 | * not return to user-mode, it will exit and clear this bit in | |
438 | * __ptrace_unlink() if it wasn't already cleared by the tracee; | |
439 | * and until then nobody can ptrace this task. | |
440 | */ | |
441 | wait_on_bit(&task->jobctl, JOBCTL_TRAPPING_BIT, TASK_KILLABLE); | |
f701e5b7 VZ |
442 | proc_ptrace_connector(task, PTRACE_ATTACH); |
443 | } | |
444 | ||
1da177e4 LT |
445 | return retval; |
446 | } | |
447 | ||
f2f0b00a ON |
448 | /** |
449 | * ptrace_traceme -- helper for PTRACE_TRACEME | |
450 | * | |
451 | * Performs checks and sets PT_PTRACED. | |
452 | * Should be used by all ptrace implementations for PTRACE_TRACEME. | |
453 | */ | |
e3e89cc5 | 454 | static int ptrace_traceme(void) |
f2f0b00a ON |
455 | { |
456 | int ret = -EPERM; | |
457 | ||
4b105cbb ON |
458 | write_lock_irq(&tasklist_lock); |
459 | /* Are we already being traced? */ | |
f2f0b00a | 460 | if (!current->ptrace) { |
f2f0b00a | 461 | ret = security_ptrace_traceme(current->parent); |
f2f0b00a ON |
462 | /* |
463 | * Check PF_EXITING to ensure ->real_parent has not passed | |
464 | * exit_ptrace(). Otherwise we don't report the error but | |
465 | * pretend ->real_parent untraces us right after return. | |
466 | */ | |
467 | if (!ret && !(current->real_parent->flags & PF_EXITING)) { | |
468 | current->ptrace = PT_PTRACED; | |
c70d9d80 | 469 | ptrace_link(current, current->real_parent); |
f2f0b00a | 470 | } |
f2f0b00a | 471 | } |
4b105cbb ON |
472 | write_unlock_irq(&tasklist_lock); |
473 | ||
f2f0b00a ON |
474 | return ret; |
475 | } | |
476 | ||
39c626ae ON |
477 | /* |
478 | * Called with irqs disabled, returns true if childs should reap themselves. | |
479 | */ | |
480 | static int ignoring_children(struct sighand_struct *sigh) | |
481 | { | |
482 | int ret; | |
483 | spin_lock(&sigh->siglock); | |
484 | ret = (sigh->action[SIGCHLD-1].sa.sa_handler == SIG_IGN) || | |
485 | (sigh->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDWAIT); | |
486 | spin_unlock(&sigh->siglock); | |
487 | return ret; | |
488 | } | |
489 | ||
490 | /* | |
491 | * Called with tasklist_lock held for writing. | |
492 | * Unlink a traced task, and clean it up if it was a traced zombie. | |
493 | * Return true if it needs to be reaped with release_task(). | |
494 | * (We can't call release_task() here because we already hold tasklist_lock.) | |
495 | * | |
496 | * If it's a zombie, our attachedness prevented normal parent notification | |
497 | * or self-reaping. Do notification now if it would have happened earlier. | |
498 | * If it should reap itself, return true. | |
499 | * | |
a7f0765e ON |
500 | * If it's our own child, there is no notification to do. But if our normal |
501 | * children self-reap, then this child was prevented by ptrace and we must | |
502 | * reap it now, in that case we must also wake up sub-threads sleeping in | |
503 | * do_wait(). | |
39c626ae ON |
504 | */ |
505 | static bool __ptrace_detach(struct task_struct *tracer, struct task_struct *p) | |
506 | { | |
9843a1e9 ON |
507 | bool dead; |
508 | ||
39c626ae ON |
509 | __ptrace_unlink(p); |
510 | ||
9843a1e9 ON |
511 | if (p->exit_state != EXIT_ZOMBIE) |
512 | return false; | |
513 | ||
514 | dead = !thread_group_leader(p); | |
515 | ||
516 | if (!dead && thread_group_empty(p)) { | |
517 | if (!same_thread_group(p->real_parent, tracer)) | |
518 | dead = do_notify_parent(p, p->exit_signal); | |
519 | else if (ignoring_children(tracer->sighand)) { | |
520 | __wake_up_parent(p, tracer); | |
9843a1e9 | 521 | dead = true; |
39c626ae ON |
522 | } |
523 | } | |
9843a1e9 ON |
524 | /* Mark it as in the process of being reaped. */ |
525 | if (dead) | |
526 | p->exit_state = EXIT_DEAD; | |
527 | return dead; | |
39c626ae ON |
528 | } |
529 | ||
e3e89cc5 | 530 | static int ptrace_detach(struct task_struct *child, unsigned int data) |
1da177e4 | 531 | { |
7ed20e1a | 532 | if (!valid_signal(data)) |
5ecfbae0 | 533 | return -EIO; |
1da177e4 LT |
534 | |
535 | /* Architecture-specific hardware disable .. */ | |
536 | ptrace_disable(child); | |
537 | ||
95c3eb76 | 538 | write_lock_irq(&tasklist_lock); |
39c626ae | 539 | /* |
64a4096c ON |
540 | * We rely on ptrace_freeze_traced(). It can't be killed and |
541 | * untraced by another thread, it can't be a zombie. | |
39c626ae | 542 | */ |
64a4096c ON |
543 | WARN_ON(!child->ptrace || child->exit_state); |
544 | /* | |
545 | * tasklist_lock avoids the race with wait_task_stopped(), see | |
546 | * the comment in ptrace_resume(). | |
547 | */ | |
548 | child->exit_code = data; | |
549 | __ptrace_detach(current, child); | |
1da177e4 LT |
550 | write_unlock_irq(&tasklist_lock); |
551 | ||
f701e5b7 | 552 | proc_ptrace_connector(child, PTRACE_DETACH); |
4576145c | 553 | |
1da177e4 LT |
554 | return 0; |
555 | } | |
556 | ||
39c626ae | 557 | /* |
c7e49c14 | 558 | * Detach all tasks we were using ptrace on. Called with tasklist held |
7c8bd232 | 559 | * for writing. |
39c626ae | 560 | */ |
7c8bd232 | 561 | void exit_ptrace(struct task_struct *tracer, struct list_head *dead) |
39c626ae ON |
562 | { |
563 | struct task_struct *p, *n; | |
c7e49c14 | 564 | |
39c626ae | 565 | list_for_each_entry_safe(p, n, &tracer->ptraced, ptrace_entry) { |
992fb6e1 | 566 | if (unlikely(p->ptrace & PT_EXITKILL)) |
079b22dc | 567 | send_sig_info(SIGKILL, SEND_SIG_PRIV, p); |
992fb6e1 | 568 | |
39c626ae | 569 | if (__ptrace_detach(tracer, p)) |
7c8bd232 | 570 | list_add(&p->ptrace_entry, dead); |
39c626ae ON |
571 | } |
572 | } | |
573 | ||
1da177e4 LT |
574 | int ptrace_readdata(struct task_struct *tsk, unsigned long src, char __user *dst, int len) |
575 | { | |
576 | int copied = 0; | |
577 | ||
578 | while (len > 0) { | |
579 | char buf[128]; | |
580 | int this_len, retval; | |
581 | ||
582 | this_len = (len > sizeof(buf)) ? sizeof(buf) : len; | |
84d77d3f EB |
583 | retval = ptrace_access_vm(tsk, src, buf, this_len, FOLL_FORCE); |
584 | ||
1da177e4 LT |
585 | if (!retval) { |
586 | if (copied) | |
587 | break; | |
588 | return -EIO; | |
589 | } | |
590 | if (copy_to_user(dst, buf, retval)) | |
591 | return -EFAULT; | |
592 | copied += retval; | |
593 | src += retval; | |
594 | dst += retval; | |
3a709703 | 595 | len -= retval; |
1da177e4 LT |
596 | } |
597 | return copied; | |
598 | } | |
599 | ||
600 | int ptrace_writedata(struct task_struct *tsk, char __user *src, unsigned long dst, int len) | |
601 | { | |
602 | int copied = 0; | |
603 | ||
604 | while (len > 0) { | |
605 | char buf[128]; | |
606 | int this_len, retval; | |
607 | ||
608 | this_len = (len > sizeof(buf)) ? sizeof(buf) : len; | |
609 | if (copy_from_user(buf, src, this_len)) | |
610 | return -EFAULT; | |
84d77d3f | 611 | retval = ptrace_access_vm(tsk, dst, buf, this_len, |
f307ab6d | 612 | FOLL_FORCE | FOLL_WRITE); |
1da177e4 LT |
613 | if (!retval) { |
614 | if (copied) | |
615 | break; | |
616 | return -EIO; | |
617 | } | |
618 | copied += retval; | |
619 | src += retval; | |
620 | dst += retval; | |
3a709703 | 621 | len -= retval; |
1da177e4 LT |
622 | } |
623 | return copied; | |
624 | } | |
625 | ||
4abf9869 | 626 | static int ptrace_setoptions(struct task_struct *child, unsigned long data) |
1da177e4 | 627 | { |
86b6c1f3 DV |
628 | unsigned flags; |
629 | ||
8c5cf9e5 DV |
630 | if (data & ~(unsigned long)PTRACE_O_MASK) |
631 | return -EINVAL; | |
632 | ||
13c4a901 | 633 | if (unlikely(data & PTRACE_O_SUSPEND_SECCOMP)) { |
97f2645f MY |
634 | if (!IS_ENABLED(CONFIG_CHECKPOINT_RESTORE) || |
635 | !IS_ENABLED(CONFIG_SECCOMP)) | |
13c4a901 TA |
636 | return -EINVAL; |
637 | ||
638 | if (!capable(CAP_SYS_ADMIN)) | |
639 | return -EPERM; | |
640 | ||
641 | if (seccomp_mode(¤t->seccomp) != SECCOMP_MODE_DISABLED || | |
642 | current->ptrace & PT_SUSPEND_SECCOMP) | |
643 | return -EPERM; | |
644 | } | |
645 | ||
86b6c1f3 DV |
646 | /* Avoid intermediate state when all opts are cleared */ |
647 | flags = child->ptrace; | |
648 | flags &= ~(PTRACE_O_MASK << PT_OPT_FLAG_SHIFT); | |
649 | flags |= (data << PT_OPT_FLAG_SHIFT); | |
650 | child->ptrace = flags; | |
1da177e4 | 651 | |
8c5cf9e5 | 652 | return 0; |
1da177e4 LT |
653 | } |
654 | ||
ae7795bc | 655 | static int ptrace_getsiginfo(struct task_struct *child, kernel_siginfo_t *info) |
1da177e4 | 656 | { |
e4961254 | 657 | unsigned long flags; |
1da177e4 LT |
658 | int error = -ESRCH; |
659 | ||
e4961254 | 660 | if (lock_task_sighand(child, &flags)) { |
1da177e4 | 661 | error = -EINVAL; |
1da177e4 | 662 | if (likely(child->last_siginfo != NULL)) { |
0752d7bf | 663 | copy_siginfo(info, child->last_siginfo); |
1da177e4 LT |
664 | error = 0; |
665 | } | |
e4961254 | 666 | unlock_task_sighand(child, &flags); |
1da177e4 | 667 | } |
1da177e4 LT |
668 | return error; |
669 | } | |
670 | ||
ae7795bc | 671 | static int ptrace_setsiginfo(struct task_struct *child, const kernel_siginfo_t *info) |
1da177e4 | 672 | { |
e4961254 | 673 | unsigned long flags; |
1da177e4 LT |
674 | int error = -ESRCH; |
675 | ||
e4961254 | 676 | if (lock_task_sighand(child, &flags)) { |
1da177e4 | 677 | error = -EINVAL; |
1da177e4 | 678 | if (likely(child->last_siginfo != NULL)) { |
0752d7bf | 679 | copy_siginfo(child->last_siginfo, info); |
1da177e4 LT |
680 | error = 0; |
681 | } | |
e4961254 | 682 | unlock_task_sighand(child, &flags); |
1da177e4 | 683 | } |
1da177e4 LT |
684 | return error; |
685 | } | |
686 | ||
84c751bd AV |
687 | static int ptrace_peek_siginfo(struct task_struct *child, |
688 | unsigned long addr, | |
689 | unsigned long data) | |
690 | { | |
691 | struct ptrace_peeksiginfo_args arg; | |
692 | struct sigpending *pending; | |
693 | struct sigqueue *q; | |
694 | int ret, i; | |
695 | ||
696 | ret = copy_from_user(&arg, (void __user *) addr, | |
697 | sizeof(struct ptrace_peeksiginfo_args)); | |
698 | if (ret) | |
699 | return -EFAULT; | |
700 | ||
701 | if (arg.flags & ~PTRACE_PEEKSIGINFO_SHARED) | |
702 | return -EINVAL; /* unknown flags */ | |
703 | ||
704 | if (arg.nr < 0) | |
705 | return -EINVAL; | |
706 | ||
707 | if (arg.flags & PTRACE_PEEKSIGINFO_SHARED) | |
708 | pending = &child->signal->shared_pending; | |
709 | else | |
710 | pending = &child->pending; | |
711 | ||
712 | for (i = 0; i < arg.nr; ) { | |
ae7795bc | 713 | kernel_siginfo_t info; |
84c751bd AV |
714 | s32 off = arg.off + i; |
715 | ||
716 | spin_lock_irq(&child->sighand->siglock); | |
717 | list_for_each_entry(q, &pending->list, list) { | |
718 | if (!off--) { | |
719 | copy_siginfo(&info, &q->info); | |
720 | break; | |
721 | } | |
722 | } | |
723 | spin_unlock_irq(&child->sighand->siglock); | |
724 | ||
725 | if (off >= 0) /* beyond the end of the list */ | |
726 | break; | |
727 | ||
728 | #ifdef CONFIG_COMPAT | |
5c465217 | 729 | if (unlikely(in_compat_syscall())) { |
84c751bd AV |
730 | compat_siginfo_t __user *uinfo = compat_ptr(data); |
731 | ||
cc731525 | 732 | if (copy_siginfo_to_user32(uinfo, &info)) { |
706b23bd MD |
733 | ret = -EFAULT; |
734 | break; | |
735 | } | |
736 | ||
84c751bd AV |
737 | } else |
738 | #endif | |
739 | { | |
740 | siginfo_t __user *uinfo = (siginfo_t __user *) data; | |
741 | ||
cc731525 | 742 | if (copy_siginfo_to_user(uinfo, &info)) { |
706b23bd MD |
743 | ret = -EFAULT; |
744 | break; | |
745 | } | |
84c751bd AV |
746 | } |
747 | ||
748 | data += sizeof(siginfo_t); | |
749 | i++; | |
750 | ||
751 | if (signal_pending(current)) | |
752 | break; | |
753 | ||
754 | cond_resched(); | |
755 | } | |
756 | ||
757 | if (i > 0) | |
758 | return i; | |
759 | ||
760 | return ret; | |
761 | } | |
36df29d7 RM |
762 | |
763 | #ifdef PTRACE_SINGLESTEP | |
764 | #define is_singlestep(request) ((request) == PTRACE_SINGLESTEP) | |
765 | #else | |
766 | #define is_singlestep(request) 0 | |
767 | #endif | |
768 | ||
5b88abbf RM |
769 | #ifdef PTRACE_SINGLEBLOCK |
770 | #define is_singleblock(request) ((request) == PTRACE_SINGLEBLOCK) | |
771 | #else | |
772 | #define is_singleblock(request) 0 | |
773 | #endif | |
774 | ||
36df29d7 RM |
775 | #ifdef PTRACE_SYSEMU |
776 | #define is_sysemu_singlestep(request) ((request) == PTRACE_SYSEMU_SINGLESTEP) | |
777 | #else | |
778 | #define is_sysemu_singlestep(request) 0 | |
779 | #endif | |
780 | ||
4abf9869 NK |
781 | static int ptrace_resume(struct task_struct *child, long request, |
782 | unsigned long data) | |
36df29d7 | 783 | { |
b72c1869 ON |
784 | bool need_siglock; |
785 | ||
36df29d7 RM |
786 | if (!valid_signal(data)) |
787 | return -EIO; | |
788 | ||
789 | if (request == PTRACE_SYSCALL) | |
790 | set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); | |
791 | else | |
792 | clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); | |
793 | ||
794 | #ifdef TIF_SYSCALL_EMU | |
795 | if (request == PTRACE_SYSEMU || request == PTRACE_SYSEMU_SINGLESTEP) | |
796 | set_tsk_thread_flag(child, TIF_SYSCALL_EMU); | |
797 | else | |
798 | clear_tsk_thread_flag(child, TIF_SYSCALL_EMU); | |
799 | #endif | |
800 | ||
5b88abbf RM |
801 | if (is_singleblock(request)) { |
802 | if (unlikely(!arch_has_block_step())) | |
803 | return -EIO; | |
804 | user_enable_block_step(child); | |
805 | } else if (is_singlestep(request) || is_sysemu_singlestep(request)) { | |
36df29d7 RM |
806 | if (unlikely(!arch_has_single_step())) |
807 | return -EIO; | |
808 | user_enable_single_step(child); | |
3a709703 | 809 | } else { |
36df29d7 | 810 | user_disable_single_step(child); |
3a709703 | 811 | } |
36df29d7 | 812 | |
b72c1869 ON |
813 | /* |
814 | * Change ->exit_code and ->state under siglock to avoid the race | |
815 | * with wait_task_stopped() in between; a non-zero ->exit_code will | |
816 | * wrongly look like another report from tracee. | |
817 | * | |
818 | * Note that we need siglock even if ->exit_code == data and/or this | |
819 | * status was not reported yet, the new status must not be cleared by | |
820 | * wait_task_stopped() after resume. | |
821 | * | |
822 | * If data == 0 we do not care if wait_task_stopped() reports the old | |
823 | * status and clears the code too; this can't race with the tracee, it | |
824 | * takes siglock after resume. | |
825 | */ | |
826 | need_siglock = data && !thread_group_empty(current); | |
827 | if (need_siglock) | |
828 | spin_lock_irq(&child->sighand->siglock); | |
36df29d7 | 829 | child->exit_code = data; |
0666fb51 | 830 | wake_up_state(child, __TASK_TRACED); |
b72c1869 ON |
831 | if (need_siglock) |
832 | spin_unlock_irq(&child->sighand->siglock); | |
36df29d7 RM |
833 | |
834 | return 0; | |
835 | } | |
836 | ||
2225a122 SS |
837 | #ifdef CONFIG_HAVE_ARCH_TRACEHOOK |
838 | ||
839 | static const struct user_regset * | |
840 | find_regset(const struct user_regset_view *view, unsigned int type) | |
841 | { | |
842 | const struct user_regset *regset; | |
843 | int n; | |
844 | ||
845 | for (n = 0; n < view->n; ++n) { | |
846 | regset = view->regsets + n; | |
847 | if (regset->core_note_type == type) | |
848 | return regset; | |
849 | } | |
850 | ||
851 | return NULL; | |
852 | } | |
853 | ||
854 | static int ptrace_regset(struct task_struct *task, int req, unsigned int type, | |
855 | struct iovec *kiov) | |
856 | { | |
857 | const struct user_regset_view *view = task_user_regset_view(task); | |
858 | const struct user_regset *regset = find_regset(view, type); | |
859 | int regset_no; | |
860 | ||
861 | if (!regset || (kiov->iov_len % regset->size) != 0) | |
c6a0dd7e | 862 | return -EINVAL; |
2225a122 SS |
863 | |
864 | regset_no = regset - view->regsets; | |
865 | kiov->iov_len = min(kiov->iov_len, | |
866 | (__kernel_size_t) (regset->n * regset->size)); | |
867 | ||
868 | if (req == PTRACE_GETREGSET) | |
869 | return copy_regset_to_user(task, view, regset_no, 0, | |
870 | kiov->iov_len, kiov->iov_base); | |
871 | else | |
872 | return copy_regset_from_user(task, view, regset_no, 0, | |
873 | kiov->iov_len, kiov->iov_base); | |
874 | } | |
875 | ||
e8440c14 JS |
876 | /* |
877 | * This is declared in linux/regset.h and defined in machine-dependent | |
878 | * code. We put the export here, near the primary machine-neutral use, | |
879 | * to ensure no machine forgets it. | |
880 | */ | |
881 | EXPORT_SYMBOL_GPL(task_user_regset_view); | |
2225a122 SS |
882 | #endif |
883 | ||
1da177e4 | 884 | int ptrace_request(struct task_struct *child, long request, |
4abf9869 | 885 | unsigned long addr, unsigned long data) |
1da177e4 | 886 | { |
fca26f26 | 887 | bool seized = child->ptrace & PT_SEIZED; |
1da177e4 | 888 | int ret = -EIO; |
ae7795bc | 889 | kernel_siginfo_t siginfo, *si; |
9fed81dc NK |
890 | void __user *datavp = (void __user *) data; |
891 | unsigned long __user *datalp = datavp; | |
fca26f26 | 892 | unsigned long flags; |
1da177e4 LT |
893 | |
894 | switch (request) { | |
16c3e389 RM |
895 | case PTRACE_PEEKTEXT: |
896 | case PTRACE_PEEKDATA: | |
897 | return generic_ptrace_peekdata(child, addr, data); | |
898 | case PTRACE_POKETEXT: | |
899 | case PTRACE_POKEDATA: | |
900 | return generic_ptrace_pokedata(child, addr, data); | |
901 | ||
1da177e4 LT |
902 | #ifdef PTRACE_OLDSETOPTIONS |
903 | case PTRACE_OLDSETOPTIONS: | |
904 | #endif | |
905 | case PTRACE_SETOPTIONS: | |
906 | ret = ptrace_setoptions(child, data); | |
907 | break; | |
908 | case PTRACE_GETEVENTMSG: | |
9fed81dc | 909 | ret = put_user(child->ptrace_message, datalp); |
1da177e4 | 910 | break; |
e16b2781 | 911 | |
84c751bd AV |
912 | case PTRACE_PEEKSIGINFO: |
913 | ret = ptrace_peek_siginfo(child, addr, data); | |
914 | break; | |
915 | ||
1da177e4 | 916 | case PTRACE_GETSIGINFO: |
e16b2781 RM |
917 | ret = ptrace_getsiginfo(child, &siginfo); |
918 | if (!ret) | |
9fed81dc | 919 | ret = copy_siginfo_to_user(datavp, &siginfo); |
1da177e4 | 920 | break; |
e16b2781 | 921 | |
1da177e4 | 922 | case PTRACE_SETSIGINFO: |
4cd2e0e7 EB |
923 | ret = copy_siginfo_from_user(&siginfo, datavp); |
924 | if (!ret) | |
e16b2781 | 925 | ret = ptrace_setsiginfo(child, &siginfo); |
1da177e4 | 926 | break; |
e16b2781 | 927 | |
fcfc2aa0 AV |
928 | case PTRACE_GETSIGMASK: { |
929 | sigset_t *mask; | |
930 | ||
29000cae AV |
931 | if (addr != sizeof(sigset_t)) { |
932 | ret = -EINVAL; | |
933 | break; | |
934 | } | |
935 | ||
fcfc2aa0 AV |
936 | if (test_tsk_restore_sigmask(child)) |
937 | mask = &child->saved_sigmask; | |
938 | else | |
939 | mask = &child->blocked; | |
940 | ||
941 | if (copy_to_user(datavp, mask, sizeof(sigset_t))) | |
29000cae AV |
942 | ret = -EFAULT; |
943 | else | |
944 | ret = 0; | |
945 | ||
946 | break; | |
fcfc2aa0 | 947 | } |
29000cae AV |
948 | |
949 | case PTRACE_SETSIGMASK: { | |
950 | sigset_t new_set; | |
951 | ||
952 | if (addr != sizeof(sigset_t)) { | |
953 | ret = -EINVAL; | |
954 | break; | |
955 | } | |
956 | ||
957 | if (copy_from_user(&new_set, datavp, sizeof(sigset_t))) { | |
958 | ret = -EFAULT; | |
959 | break; | |
960 | } | |
961 | ||
962 | sigdelsetmask(&new_set, sigmask(SIGKILL)|sigmask(SIGSTOP)); | |
963 | ||
964 | /* | |
965 | * Every thread does recalc_sigpending() after resume, so | |
966 | * retarget_shared_pending() and recalc_sigpending() are not | |
967 | * called here. | |
968 | */ | |
969 | spin_lock_irq(&child->sighand->siglock); | |
970 | child->blocked = new_set; | |
971 | spin_unlock_irq(&child->sighand->siglock); | |
972 | ||
fcfc2aa0 AV |
973 | clear_tsk_restore_sigmask(child); |
974 | ||
29000cae AV |
975 | ret = 0; |
976 | break; | |
977 | } | |
978 | ||
fca26f26 TH |
979 | case PTRACE_INTERRUPT: |
980 | /* | |
981 | * Stop tracee without any side-effect on signal or job | |
982 | * control. At least one trap is guaranteed to happen | |
983 | * after this request. If @child is already trapped, the | |
984 | * current trap is not disturbed and another trap will | |
985 | * happen after the current trap is ended with PTRACE_CONT. | |
986 | * | |
987 | * The actual trap might not be PTRACE_EVENT_STOP trap but | |
988 | * the pending condition is cleared regardless. | |
989 | */ | |
990 | if (unlikely(!seized || !lock_task_sighand(child, &flags))) | |
991 | break; | |
992 | ||
544b2c91 TH |
993 | /* |
994 | * INTERRUPT doesn't disturb existing trap sans one | |
995 | * exception. If ptracer issued LISTEN for the current | |
996 | * STOP, this INTERRUPT should clear LISTEN and re-trap | |
997 | * tracee into STOP. | |
998 | */ | |
fca26f26 | 999 | if (likely(task_set_jobctl_pending(child, JOBCTL_TRAP_STOP))) |
910ffdb1 | 1000 | ptrace_signal_wake_up(child, child->jobctl & JOBCTL_LISTENING); |
544b2c91 TH |
1001 | |
1002 | unlock_task_sighand(child, &flags); | |
1003 | ret = 0; | |
1004 | break; | |
1005 | ||
1006 | case PTRACE_LISTEN: | |
1007 | /* | |
1008 | * Listen for events. Tracee must be in STOP. It's not | |
1009 | * resumed per-se but is not considered to be in TRACED by | |
1010 | * wait(2) or ptrace(2). If an async event (e.g. group | |
1011 | * stop state change) happens, tracee will enter STOP trap | |
1012 | * again. Alternatively, ptracer can issue INTERRUPT to | |
1013 | * finish listening and re-trap tracee into STOP. | |
1014 | */ | |
1015 | if (unlikely(!seized || !lock_task_sighand(child, &flags))) | |
1016 | break; | |
1017 | ||
1018 | si = child->last_siginfo; | |
f9d81f61 ON |
1019 | if (likely(si && (si->si_code >> 8) == PTRACE_EVENT_STOP)) { |
1020 | child->jobctl |= JOBCTL_LISTENING; | |
1021 | /* | |
1022 | * If NOTIFY is set, it means event happened between | |
1023 | * start of this trap and now. Trigger re-trap. | |
1024 | */ | |
1025 | if (child->jobctl & JOBCTL_TRAP_NOTIFY) | |
910ffdb1 | 1026 | ptrace_signal_wake_up(child, true); |
f9d81f61 ON |
1027 | ret = 0; |
1028 | } | |
fca26f26 | 1029 | unlock_task_sighand(child, &flags); |
fca26f26 TH |
1030 | break; |
1031 | ||
1bcf5482 AD |
1032 | case PTRACE_DETACH: /* detach a process that was attached. */ |
1033 | ret = ptrace_detach(child, data); | |
1034 | break; | |
36df29d7 | 1035 | |
9c1a1259 MF |
1036 | #ifdef CONFIG_BINFMT_ELF_FDPIC |
1037 | case PTRACE_GETFDPIC: { | |
e0129ef9 | 1038 | struct mm_struct *mm = get_task_mm(child); |
9c1a1259 MF |
1039 | unsigned long tmp = 0; |
1040 | ||
e0129ef9 ON |
1041 | ret = -ESRCH; |
1042 | if (!mm) | |
1043 | break; | |
1044 | ||
9c1a1259 MF |
1045 | switch (addr) { |
1046 | case PTRACE_GETFDPIC_EXEC: | |
e0129ef9 | 1047 | tmp = mm->context.exec_fdpic_loadmap; |
9c1a1259 MF |
1048 | break; |
1049 | case PTRACE_GETFDPIC_INTERP: | |
e0129ef9 | 1050 | tmp = mm->context.interp_fdpic_loadmap; |
9c1a1259 MF |
1051 | break; |
1052 | default: | |
1053 | break; | |
1054 | } | |
e0129ef9 | 1055 | mmput(mm); |
9c1a1259 | 1056 | |
9fed81dc | 1057 | ret = put_user(tmp, datalp); |
9c1a1259 MF |
1058 | break; |
1059 | } | |
1060 | #endif | |
1061 | ||
36df29d7 RM |
1062 | #ifdef PTRACE_SINGLESTEP |
1063 | case PTRACE_SINGLESTEP: | |
1064 | #endif | |
5b88abbf RM |
1065 | #ifdef PTRACE_SINGLEBLOCK |
1066 | case PTRACE_SINGLEBLOCK: | |
1067 | #endif | |
36df29d7 RM |
1068 | #ifdef PTRACE_SYSEMU |
1069 | case PTRACE_SYSEMU: | |
1070 | case PTRACE_SYSEMU_SINGLESTEP: | |
1071 | #endif | |
1072 | case PTRACE_SYSCALL: | |
1073 | case PTRACE_CONT: | |
1074 | return ptrace_resume(child, request, data); | |
1075 | ||
1076 | case PTRACE_KILL: | |
1077 | if (child->exit_state) /* already dead */ | |
1078 | return 0; | |
1079 | return ptrace_resume(child, request, SIGKILL); | |
1080 | ||
2225a122 SS |
1081 | #ifdef CONFIG_HAVE_ARCH_TRACEHOOK |
1082 | case PTRACE_GETREGSET: | |
29000cae | 1083 | case PTRACE_SETREGSET: { |
2225a122 | 1084 | struct iovec kiov; |
9fed81dc | 1085 | struct iovec __user *uiov = datavp; |
2225a122 | 1086 | |
96d4f267 | 1087 | if (!access_ok(uiov, sizeof(*uiov))) |
2225a122 SS |
1088 | return -EFAULT; |
1089 | ||
1090 | if (__get_user(kiov.iov_base, &uiov->iov_base) || | |
1091 | __get_user(kiov.iov_len, &uiov->iov_len)) | |
1092 | return -EFAULT; | |
1093 | ||
1094 | ret = ptrace_regset(child, request, addr, &kiov); | |
1095 | if (!ret) | |
1096 | ret = __put_user(kiov.iov_len, &uiov->iov_len); | |
1097 | break; | |
1098 | } | |
1099 | #endif | |
f8e529ed TA |
1100 | |
1101 | case PTRACE_SECCOMP_GET_FILTER: | |
1102 | ret = seccomp_get_filter(child, addr, datavp); | |
1103 | break; | |
1104 | ||
26500475 TA |
1105 | case PTRACE_SECCOMP_GET_METADATA: |
1106 | ret = seccomp_get_metadata(child, addr, datavp); | |
1107 | break; | |
1108 | ||
1da177e4 LT |
1109 | default: |
1110 | break; | |
1111 | } | |
1112 | ||
1113 | return ret; | |
1114 | } | |
481bed45 | 1115 | |
0ac15559 CH |
1116 | #ifndef arch_ptrace_attach |
1117 | #define arch_ptrace_attach(child) do { } while (0) | |
1118 | #endif | |
1119 | ||
4abf9869 NK |
1120 | SYSCALL_DEFINE4(ptrace, long, request, long, pid, unsigned long, addr, |
1121 | unsigned long, data) | |
481bed45 CH |
1122 | { |
1123 | struct task_struct *child; | |
1124 | long ret; | |
1125 | ||
6b9c7ed8 CH |
1126 | if (request == PTRACE_TRACEME) { |
1127 | ret = ptrace_traceme(); | |
6ea6dd93 HS |
1128 | if (!ret) |
1129 | arch_ptrace_attach(current); | |
481bed45 | 1130 | goto out; |
6b9c7ed8 CH |
1131 | } |
1132 | ||
2ee08260 MR |
1133 | child = find_get_task_by_vpid(pid); |
1134 | if (!child) { | |
1135 | ret = -ESRCH; | |
6b9c7ed8 CH |
1136 | goto out; |
1137 | } | |
481bed45 | 1138 | |
3544d72a | 1139 | if (request == PTRACE_ATTACH || request == PTRACE_SEIZE) { |
aa9147c9 | 1140 | ret = ptrace_attach(child, request, addr, data); |
0ac15559 CH |
1141 | /* |
1142 | * Some architectures need to do book-keeping after | |
1143 | * a ptrace attach. | |
1144 | */ | |
1145 | if (!ret) | |
1146 | arch_ptrace_attach(child); | |
005f18df | 1147 | goto out_put_task_struct; |
481bed45 CH |
1148 | } |
1149 | ||
fca26f26 TH |
1150 | ret = ptrace_check_attach(child, request == PTRACE_KILL || |
1151 | request == PTRACE_INTERRUPT); | |
481bed45 CH |
1152 | if (ret < 0) |
1153 | goto out_put_task_struct; | |
1154 | ||
1155 | ret = arch_ptrace(child, request, addr, data); | |
9899d11f ON |
1156 | if (ret || request != PTRACE_DETACH) |
1157 | ptrace_unfreeze_traced(child); | |
481bed45 CH |
1158 | |
1159 | out_put_task_struct: | |
1160 | put_task_struct(child); | |
1161 | out: | |
481bed45 CH |
1162 | return ret; |
1163 | } | |
76647323 | 1164 | |
4abf9869 NK |
1165 | int generic_ptrace_peekdata(struct task_struct *tsk, unsigned long addr, |
1166 | unsigned long data) | |
76647323 AD |
1167 | { |
1168 | unsigned long tmp; | |
1169 | int copied; | |
1170 | ||
84d77d3f | 1171 | copied = ptrace_access_vm(tsk, addr, &tmp, sizeof(tmp), FOLL_FORCE); |
76647323 AD |
1172 | if (copied != sizeof(tmp)) |
1173 | return -EIO; | |
1174 | return put_user(tmp, (unsigned long __user *)data); | |
1175 | } | |
f284ce72 | 1176 | |
4abf9869 NK |
1177 | int generic_ptrace_pokedata(struct task_struct *tsk, unsigned long addr, |
1178 | unsigned long data) | |
f284ce72 AD |
1179 | { |
1180 | int copied; | |
1181 | ||
84d77d3f | 1182 | copied = ptrace_access_vm(tsk, addr, &data, sizeof(data), |
f307ab6d | 1183 | FOLL_FORCE | FOLL_WRITE); |
f284ce72 AD |
1184 | return (copied == sizeof(data)) ? 0 : -EIO; |
1185 | } | |
032d82d9 | 1186 | |
96b8936a | 1187 | #if defined CONFIG_COMPAT |
032d82d9 RM |
1188 | |
1189 | int compat_ptrace_request(struct task_struct *child, compat_long_t request, | |
1190 | compat_ulong_t addr, compat_ulong_t data) | |
1191 | { | |
1192 | compat_ulong_t __user *datap = compat_ptr(data); | |
1193 | compat_ulong_t word; | |
ae7795bc | 1194 | kernel_siginfo_t siginfo; |
032d82d9 RM |
1195 | int ret; |
1196 | ||
1197 | switch (request) { | |
1198 | case PTRACE_PEEKTEXT: | |
1199 | case PTRACE_PEEKDATA: | |
84d77d3f | 1200 | ret = ptrace_access_vm(child, addr, &word, sizeof(word), |
f307ab6d | 1201 | FOLL_FORCE); |
032d82d9 RM |
1202 | if (ret != sizeof(word)) |
1203 | ret = -EIO; | |
1204 | else | |
1205 | ret = put_user(word, datap); | |
1206 | break; | |
1207 | ||
1208 | case PTRACE_POKETEXT: | |
1209 | case PTRACE_POKEDATA: | |
84d77d3f | 1210 | ret = ptrace_access_vm(child, addr, &data, sizeof(data), |
f307ab6d | 1211 | FOLL_FORCE | FOLL_WRITE); |
032d82d9 RM |
1212 | ret = (ret != sizeof(data) ? -EIO : 0); |
1213 | break; | |
1214 | ||
1215 | case PTRACE_GETEVENTMSG: | |
1216 | ret = put_user((compat_ulong_t) child->ptrace_message, datap); | |
1217 | break; | |
1218 | ||
e16b2781 RM |
1219 | case PTRACE_GETSIGINFO: |
1220 | ret = ptrace_getsiginfo(child, &siginfo); | |
1221 | if (!ret) | |
1222 | ret = copy_siginfo_to_user32( | |
1223 | (struct compat_siginfo __user *) datap, | |
1224 | &siginfo); | |
1225 | break; | |
1226 | ||
1227 | case PTRACE_SETSIGINFO: | |
4cd2e0e7 EB |
1228 | ret = copy_siginfo_from_user32( |
1229 | &siginfo, (struct compat_siginfo __user *) datap); | |
1230 | if (!ret) | |
e16b2781 RM |
1231 | ret = ptrace_setsiginfo(child, &siginfo); |
1232 | break; | |
2225a122 SS |
1233 | #ifdef CONFIG_HAVE_ARCH_TRACEHOOK |
1234 | case PTRACE_GETREGSET: | |
1235 | case PTRACE_SETREGSET: | |
1236 | { | |
1237 | struct iovec kiov; | |
1238 | struct compat_iovec __user *uiov = | |
1239 | (struct compat_iovec __user *) datap; | |
1240 | compat_uptr_t ptr; | |
1241 | compat_size_t len; | |
1242 | ||
96d4f267 | 1243 | if (!access_ok(uiov, sizeof(*uiov))) |
2225a122 SS |
1244 | return -EFAULT; |
1245 | ||
1246 | if (__get_user(ptr, &uiov->iov_base) || | |
1247 | __get_user(len, &uiov->iov_len)) | |
1248 | return -EFAULT; | |
1249 | ||
1250 | kiov.iov_base = compat_ptr(ptr); | |
1251 | kiov.iov_len = len; | |
1252 | ||
1253 | ret = ptrace_regset(child, request, addr, &kiov); | |
1254 | if (!ret) | |
1255 | ret = __put_user(kiov.iov_len, &uiov->iov_len); | |
1256 | break; | |
1257 | } | |
1258 | #endif | |
e16b2781 | 1259 | |
032d82d9 RM |
1260 | default: |
1261 | ret = ptrace_request(child, request, addr, data); | |
1262 | } | |
1263 | ||
1264 | return ret; | |
1265 | } | |
c269f196 | 1266 | |
62a6fa97 HC |
1267 | COMPAT_SYSCALL_DEFINE4(ptrace, compat_long_t, request, compat_long_t, pid, |
1268 | compat_long_t, addr, compat_long_t, data) | |
c269f196 RM |
1269 | { |
1270 | struct task_struct *child; | |
1271 | long ret; | |
1272 | ||
c269f196 RM |
1273 | if (request == PTRACE_TRACEME) { |
1274 | ret = ptrace_traceme(); | |
1275 | goto out; | |
1276 | } | |
1277 | ||
2ee08260 MR |
1278 | child = find_get_task_by_vpid(pid); |
1279 | if (!child) { | |
1280 | ret = -ESRCH; | |
c269f196 RM |
1281 | goto out; |
1282 | } | |
1283 | ||
3544d72a | 1284 | if (request == PTRACE_ATTACH || request == PTRACE_SEIZE) { |
aa9147c9 | 1285 | ret = ptrace_attach(child, request, addr, data); |
c269f196 RM |
1286 | /* |
1287 | * Some architectures need to do book-keeping after | |
1288 | * a ptrace attach. | |
1289 | */ | |
1290 | if (!ret) | |
1291 | arch_ptrace_attach(child); | |
1292 | goto out_put_task_struct; | |
1293 | } | |
1294 | ||
fca26f26 TH |
1295 | ret = ptrace_check_attach(child, request == PTRACE_KILL || |
1296 | request == PTRACE_INTERRUPT); | |
9899d11f | 1297 | if (!ret) { |
c269f196 | 1298 | ret = compat_arch_ptrace(child, request, addr, data); |
9899d11f ON |
1299 | if (ret || request != PTRACE_DETACH) |
1300 | ptrace_unfreeze_traced(child); | |
1301 | } | |
c269f196 RM |
1302 | |
1303 | out_put_task_struct: | |
1304 | put_task_struct(child); | |
1305 | out: | |
c269f196 RM |
1306 | return ret; |
1307 | } | |
96b8936a | 1308 | #endif /* CONFIG_COMPAT */ |