Thomas Gleixner | 457c899 | 2019-05-19 13:08:55 +0100 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0-only |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2 | /* |
| 3 | * linux/kernel/ptrace.c |
| 4 | * |
| 5 | * (C) Copyright 1999 Linus Torvalds |
| 6 | * |
| 7 | * Common interfaces for "ptrace()" which we do not want |
| 8 | * to continually duplicate across every architecture. |
| 9 | */ |
| 10 | |
Randy.Dunlap | c59ede7 | 2006-01-11 12:17:46 -0800 | [diff] [blame] | 11 | #include <linux/capability.h> |
Paul Gortmaker | 9984de1 | 2011-05-23 14:51:41 -0400 | [diff] [blame] | 12 | #include <linux/export.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 13 | #include <linux/sched.h> |
Ingo Molnar | 6e84f31 | 2017-02-08 18:51:29 +0100 | [diff] [blame] | 14 | #include <linux/sched/mm.h> |
Ingo Molnar | f7ccbae | 2017-02-08 18:51:30 +0100 | [diff] [blame] | 15 | #include <linux/sched/coredump.h> |
Ingo Molnar | 2993002 | 2017-02-08 18:51:36 +0100 | [diff] [blame] | 16 | #include <linux/sched/task.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 17 | #include <linux/errno.h> |
| 18 | #include <linux/mm.h> |
| 19 | #include <linux/highmem.h> |
| 20 | #include <linux/pagemap.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 21 | #include <linux/ptrace.h> |
| 22 | #include <linux/security.h> |
Jesper Juhl | 7ed20e1 | 2005-05-01 08:59:14 -0700 | [diff] [blame] | 23 | #include <linux/signal.h> |
Kent Overstreet | a27bb33 | 2013-05-07 16:19:08 -0700 | [diff] [blame] | 24 | #include <linux/uio.h> |
Al Viro | a5cb013 | 2007-03-20 13:58:35 -0400 | [diff] [blame] | 25 | #include <linux/audit.h> |
Pavel Emelyanov | b488893 | 2007-10-18 23:40:14 -0700 | [diff] [blame] | 26 | #include <linux/pid_namespace.h> |
Adrian Bunk | f17d30a | 2008-02-06 01:36:44 -0800 | [diff] [blame] | 27 | #include <linux/syscalls.h> |
Roland McGrath | 3a70970 | 2009-04-07 23:21:06 -0700 | [diff] [blame] | 28 | #include <linux/uaccess.h> |
Suresh Siddha | 2225a12 | 2010-02-11 11:51:00 -0800 | [diff] [blame] | 29 | #include <linux/regset.h> |
Frederic Weisbecker | bf26c01 | 2011-04-07 16:53:20 +0200 | [diff] [blame] | 30 | #include <linux/hw_breakpoint.h> |
Vladimir Zapolskiy | f701e5b | 2011-07-15 20:45:18 +0300 | [diff] [blame] | 31 | #include <linux/cn_proc.h> |
Andrey Vagin | 84c751b | 2013-04-30 15:27:59 -0700 | [diff] [blame] | 32 | #include <linux/compat.h> |
Andrei Vagin | fcfc2aa0 | 2019-03-28 20:44:13 -0700 | [diff] [blame] | 33 | #include <linux/sched/signal.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | |
Elvira Khabirova | 201766a | 2019-07-16 16:29:42 -0700 | [diff] [blame] | 35 | #include <asm/syscall.h> /* for syscall_get_* */ |
| 36 | |
Eric W. Biederman | 84d77d3 | 2016-11-22 12:06:50 -0600 | [diff] [blame] | 37 | /* |
| 38 | * Access another process' address space via ptrace. |
| 39 | * Source/target buffer must be kernel space, |
| 40 | * Do not walk the page table directly, use get_user_pages |
| 41 | */ |
| 42 | int ptrace_access_vm(struct task_struct *tsk, unsigned long addr, |
| 43 | void *buf, int len, unsigned int gup_flags) |
| 44 | { |
| 45 | struct mm_struct *mm; |
| 46 | int ret; |
| 47 | |
| 48 | mm = get_task_mm(tsk); |
| 49 | if (!mm) |
| 50 | return 0; |
| 51 | |
| 52 | if (!tsk->ptrace || |
| 53 | (current != tsk->parent) || |
| 54 | ((get_dumpable(mm) != SUID_DUMP_USER) && |
| 55 | !ptracer_capable(tsk, mm->user_ns))) { |
| 56 | mmput(mm); |
| 57 | return 0; |
| 58 | } |
| 59 | |
John Hubbard | d3f5ffc | 2020-12-14 19:07:45 -0800 | [diff] [blame] | 60 | ret = __access_remote_vm(mm, addr, buf, len, gup_flags); |
Eric W. Biederman | 84d77d3 | 2016-11-22 12:06:50 -0600 | [diff] [blame] | 61 | mmput(mm); |
| 62 | |
| 63 | return ret; |
| 64 | } |
| 65 | |
Markus Metzger | bf53de9 | 2008-12-19 15:10:24 +0100 | [diff] [blame] | 66 | |
Eric W. Biederman | c70d9d8 | 2017-05-22 15:40:12 -0500 | [diff] [blame] | 67 | void __ptrace_link(struct task_struct *child, struct task_struct *new_parent, |
| 68 | const struct cred *ptracer_cred) |
| 69 | { |
| 70 | BUG_ON(!list_empty(&child->ptrace_entry)); |
| 71 | list_add(&child->ptrace_entry, &new_parent->ptraced); |
| 72 | child->parent = new_parent; |
| 73 | child->ptracer_cred = get_cred(ptracer_cred); |
| 74 | } |
| 75 | |
Markus Metzger | bf53de9 | 2008-12-19 15:10:24 +0100 | [diff] [blame] | 76 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 77 | * ptrace a task: make the debugger its new parent and |
| 78 | * move it to the ptrace list. |
| 79 | * |
| 80 | * Must be called with the tasklist lock write-held. |
| 81 | */ |
Eric W. Biederman | c70d9d8 | 2017-05-22 15:40:12 -0500 | [diff] [blame] | 82 | static void ptrace_link(struct task_struct *child, struct task_struct *new_parent) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 83 | { |
Jann Horn | 6994eef | 2019-07-04 17:32:23 +0200 | [diff] [blame] | 84 | __ptrace_link(child, new_parent, current_cred()); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 85 | } |
Roland McGrath | 3a70970 | 2009-04-07 23:21:06 -0700 | [diff] [blame] | 86 | |
Tejun Heo | e3bd058 | 2011-03-23 10:37:01 +0100 | [diff] [blame] | 87 | /** |
| 88 | * __ptrace_unlink - unlink ptracee and restore its execution state |
| 89 | * @child: ptracee to be unlinked |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 90 | * |
Tejun Heo | 0e9f0a4 | 2011-03-23 10:37:01 +0100 | [diff] [blame] | 91 | * Remove @child from the ptrace list, move it back to the original parent, |
| 92 | * and restore the execution state so that it conforms to the group stop |
| 93 | * state. |
| 94 | * |
| 95 | * Unlinking can happen via two paths - explicit PTRACE_DETACH or ptracer |
| 96 | * exiting. For PTRACE_DETACH, unless the ptracee has been killed between |
| 97 | * ptrace_check_attach() and here, it's guaranteed to be in TASK_TRACED. |
| 98 | * If the ptracer is exiting, the ptracee can be in any state. |
| 99 | * |
| 100 | * After detach, the ptracee should be in a state which conforms to the |
| 101 | * group stop. If the group is stopped or in the process of stopping, the |
| 102 | * ptracee should be put into TASK_STOPPED; otherwise, it should be woken |
| 103 | * up from TASK_TRACED. |
| 104 | * |
| 105 | * If the ptracee is in TASK_TRACED and needs to be moved to TASK_STOPPED, |
| 106 | * it goes through TRACED -> RUNNING -> STOPPED transition which is similar |
| 107 | * to but in the opposite direction of what happens while attaching to a |
| 108 | * stopped task. However, in this direction, the intermediate RUNNING |
| 109 | * state is not hidden even from the current ptracer and if it immediately |
| 110 | * re-attaches and performs a WNOHANG wait(2), it may fail. |
Tejun Heo | e3bd058 | 2011-03-23 10:37:01 +0100 | [diff] [blame] | 111 | * |
| 112 | * CONTEXT: |
| 113 | * write_lock_irq(tasklist_lock) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 114 | */ |
Ingo Molnar | 36c8b58 | 2006-07-03 00:25:41 -0700 | [diff] [blame] | 115 | void __ptrace_unlink(struct task_struct *child) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 116 | { |
Eric W. Biederman | 64b875f | 2016-11-14 18:48:07 -0600 | [diff] [blame] | 117 | const struct cred *old_cred; |
Oleg Nesterov | 5ecfbae | 2006-02-15 22:50:10 +0300 | [diff] [blame] | 118 | BUG_ON(!child->ptrace); |
| 119 | |
Gabriel Krisman Bertazi | 64c19ba | 2020-11-16 12:42:02 -0500 | [diff] [blame] | 120 | clear_task_syscall_work(child, SYSCALL_TRACE); |
Gabriel Krisman Bertazi | 64eb35f | 2020-11-16 12:42:03 -0500 | [diff] [blame] | 121 | #if defined(CONFIG_GENERIC_ENTRY) || defined(TIF_SYSCALL_EMU) |
| 122 | clear_task_syscall_work(child, SYSCALL_EMU); |
Sudeep Holla | 15532fd | 2019-05-23 10:06:15 +0100 | [diff] [blame] | 123 | #endif |
Ales Novak | 0a5bf40 | 2016-10-11 13:53:46 -0700 | [diff] [blame] | 124 | |
Roland McGrath | f470021 | 2008-03-24 18:36:23 -0700 | [diff] [blame] | 125 | child->parent = child->real_parent; |
| 126 | list_del_init(&child->ptrace_entry); |
Eric W. Biederman | 64b875f | 2016-11-14 18:48:07 -0600 | [diff] [blame] | 127 | old_cred = child->ptracer_cred; |
| 128 | child->ptracer_cred = NULL; |
| 129 | put_cred(old_cred); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 130 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 131 | spin_lock(&child->sighand->siglock); |
Oleg Nesterov | 1333ab0 | 2016-03-22 14:25:33 -0700 | [diff] [blame] | 132 | child->ptrace = 0; |
Tejun Heo | 0e9f0a4 | 2011-03-23 10:37:01 +0100 | [diff] [blame] | 133 | /* |
Tejun Heo | 73ddff2 | 2011-06-14 11:20:14 +0200 | [diff] [blame] | 134 | * Clear all pending traps and TRAPPING. TRAPPING should be |
| 135 | * cleared regardless of JOBCTL_STOP_PENDING. Do it explicitly. |
| 136 | */ |
| 137 | task_clear_jobctl_pending(child, JOBCTL_TRAP_MASK); |
| 138 | task_clear_jobctl_trapping(child); |
| 139 | |
| 140 | /* |
Tejun Heo | a8f072c | 2011-06-02 11:13:59 +0200 | [diff] [blame] | 141 | * Reinstate JOBCTL_STOP_PENDING if group stop is in effect and |
Tejun Heo | 0e9f0a4 | 2011-03-23 10:37:01 +0100 | [diff] [blame] | 142 | * @child isn't dead. |
| 143 | */ |
| 144 | if (!(child->flags & PF_EXITING) && |
| 145 | (child->signal->flags & SIGNAL_STOP_STOPPED || |
Oleg Nesterov | 8a88951 | 2012-01-04 17:29:20 +0100 | [diff] [blame] | 146 | child->signal->group_stop_count)) { |
Tejun Heo | a8f072c | 2011-06-02 11:13:59 +0200 | [diff] [blame] | 147 | child->jobctl |= JOBCTL_STOP_PENDING; |
Tejun Heo | 0e9f0a4 | 2011-03-23 10:37:01 +0100 | [diff] [blame] | 148 | |
Oleg Nesterov | 8a88951 | 2012-01-04 17:29:20 +0100 | [diff] [blame] | 149 | /* |
| 150 | * This is only possible if this thread was cloned by the |
| 151 | * traced task running in the stopped group, set the signal |
| 152 | * for the future reports. |
| 153 | * FIXME: we should change ptrace_init_task() to handle this |
| 154 | * case. |
| 155 | */ |
| 156 | if (!(child->jobctl & JOBCTL_STOP_SIGMASK)) |
| 157 | child->jobctl |= SIGSTOP; |
| 158 | } |
| 159 | |
Tejun Heo | 0e9f0a4 | 2011-03-23 10:37:01 +0100 | [diff] [blame] | 160 | /* |
| 161 | * If transition to TASK_STOPPED is pending or in TASK_TRACED, kick |
| 162 | * @child in the butt. Note that @resume should be used iff @child |
| 163 | * is in TASK_TRACED; otherwise, we might unduly disrupt |
| 164 | * TASK_KILLABLE sleeps. |
| 165 | */ |
Tejun Heo | a8f072c | 2011-06-02 11:13:59 +0200 | [diff] [blame] | 166 | if (child->jobctl & JOBCTL_STOP_PENDING || task_is_traced(child)) |
Oleg Nesterov | 910ffdb1 | 2013-01-21 20:47:41 +0100 | [diff] [blame] | 167 | ptrace_signal_wake_up(child, true); |
Tejun Heo | 0e9f0a4 | 2011-03-23 10:37:01 +0100 | [diff] [blame] | 168 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 169 | spin_unlock(&child->sighand->siglock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 170 | } |
| 171 | |
Oleg Nesterov | 9899d11 | 2013-01-21 20:48:00 +0100 | [diff] [blame] | 172 | /* Ensure that nothing can wake it up, even SIGKILL */ |
| 173 | static bool ptrace_freeze_traced(struct task_struct *task) |
| 174 | { |
| 175 | bool ret = false; |
| 176 | |
| 177 | /* Lockless, nobody but us can set this flag */ |
| 178 | if (task->jobctl & JOBCTL_LISTENING) |
| 179 | return ret; |
| 180 | |
| 181 | spin_lock_irq(&task->sighand->siglock); |
| 182 | if (task_is_traced(task) && !__fatal_signal_pending(task)) { |
| 183 | task->state = __TASK_TRACED; |
| 184 | ret = true; |
| 185 | } |
| 186 | spin_unlock_irq(&task->sighand->siglock); |
| 187 | |
| 188 | return ret; |
| 189 | } |
| 190 | |
| 191 | static void ptrace_unfreeze_traced(struct task_struct *task) |
| 192 | { |
| 193 | if (task->state != __TASK_TRACED) |
| 194 | return; |
| 195 | |
| 196 | WARN_ON(!task->ptrace || task->parent != current); |
| 197 | |
bsegall@google.com | 5402e97 | 2017-04-07 16:04:51 -0700 | [diff] [blame] | 198 | /* |
| 199 | * PTRACE_LISTEN can allow ptrace_trap_notify to wake us up remotely. |
| 200 | * Recheck state under the lock to close this race. |
| 201 | */ |
Oleg Nesterov | 9899d11 | 2013-01-21 20:48:00 +0100 | [diff] [blame] | 202 | spin_lock_irq(&task->sighand->siglock); |
bsegall@google.com | 5402e97 | 2017-04-07 16:04:51 -0700 | [diff] [blame] | 203 | if (task->state == __TASK_TRACED) { |
| 204 | if (__fatal_signal_pending(task)) |
| 205 | wake_up_state(task, __TASK_TRACED); |
| 206 | else |
| 207 | task->state = TASK_TRACED; |
| 208 | } |
Oleg Nesterov | 9899d11 | 2013-01-21 20:48:00 +0100 | [diff] [blame] | 209 | spin_unlock_irq(&task->sighand->siglock); |
| 210 | } |
| 211 | |
Tejun Heo | 755e276 | 2011-06-02 11:13:59 +0200 | [diff] [blame] | 212 | /** |
| 213 | * ptrace_check_attach - check whether ptracee is ready for ptrace operation |
| 214 | * @child: ptracee to check for |
| 215 | * @ignore_state: don't check whether @child is currently %TASK_TRACED |
| 216 | * |
| 217 | * Check whether @child is being ptraced by %current and ready for further |
| 218 | * ptrace operations. If @ignore_state is %false, @child also should be in |
| 219 | * %TASK_TRACED state and on return the child is guaranteed to be traced |
| 220 | * and not executing. If @ignore_state is %true, @child can be in any |
| 221 | * state. |
| 222 | * |
| 223 | * CONTEXT: |
| 224 | * Grabs and releases tasklist_lock and @child->sighand->siglock. |
| 225 | * |
| 226 | * RETURNS: |
| 227 | * 0 on success, -ESRCH if %child is not ready. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 228 | */ |
Oleg Nesterov | edea0d0 | 2013-01-20 20:25:47 +0100 | [diff] [blame] | 229 | static int ptrace_check_attach(struct task_struct *child, bool ignore_state) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 230 | { |
| 231 | int ret = -ESRCH; |
| 232 | |
| 233 | /* |
| 234 | * We take the read lock around doing both checks to close a |
| 235 | * possible race where someone else was tracing our child and |
| 236 | * detached between these two checks. After this locked check, |
| 237 | * we are sure that this is our traced child and that can only |
| 238 | * be changed by us so it's not changing right after this. |
| 239 | */ |
| 240 | read_lock(&tasklist_lock); |
Oleg Nesterov | 9899d11 | 2013-01-21 20:48:00 +0100 | [diff] [blame] | 241 | if (child->ptrace && child->parent == current) { |
| 242 | WARN_ON(child->state == __TASK_TRACED); |
Oleg Nesterov | c0c0b64 | 2008-02-08 04:19:00 -0800 | [diff] [blame] | 243 | /* |
| 244 | * child->sighand can't be NULL, release_task() |
| 245 | * does ptrace_unlink() before __exit_signal(). |
| 246 | */ |
Oleg Nesterov | 9899d11 | 2013-01-21 20:48:00 +0100 | [diff] [blame] | 247 | if (ignore_state || ptrace_freeze_traced(child)) |
Oleg Nesterov | 321fb56 | 2011-04-01 20:13:01 +0200 | [diff] [blame] | 248 | ret = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 249 | } |
| 250 | read_unlock(&tasklist_lock); |
| 251 | |
Oleg Nesterov | 9899d11 | 2013-01-21 20:48:00 +0100 | [diff] [blame] | 252 | if (!ret && !ignore_state) { |
| 253 | if (!wait_task_inactive(child, __TASK_TRACED)) { |
| 254 | /* |
| 255 | * This can only happen if may_ptrace_stop() fails and |
| 256 | * ptrace_stop() changes ->state back to TASK_RUNNING, |
| 257 | * so we should not worry about leaking __TASK_TRACED. |
| 258 | */ |
| 259 | WARN_ON(child->state == __TASK_TRACED); |
| 260 | ret = -ESRCH; |
| 261 | } |
| 262 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 263 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 264 | return ret; |
| 265 | } |
| 266 | |
Mickaël Salaün | cf23705 | 2020-10-30 13:38:48 +0100 | [diff] [blame] | 267 | static bool ptrace_has_cap(struct user_namespace *ns, unsigned int mode) |
Eric Paris | 69f594a | 2012-01-03 12:25:15 -0500 | [diff] [blame] | 268 | { |
| 269 | if (mode & PTRACE_MODE_NOAUDIT) |
Mickaël Salaün | cf23705 | 2020-10-30 13:38:48 +0100 | [diff] [blame] | 270 | return ns_capable_noaudit(ns, CAP_SYS_PTRACE); |
| 271 | return ns_capable(ns, CAP_SYS_PTRACE); |
Eric Paris | 69f594a | 2012-01-03 12:25:15 -0500 | [diff] [blame] | 272 | } |
| 273 | |
Tetsuo Handa | 9f99798 | 2012-07-31 20:37:00 +0900 | [diff] [blame] | 274 | /* Returns 0 on success, -errno on denial. */ |
| 275 | static int __ptrace_may_access(struct task_struct *task, unsigned int mode) |
Miklos Szeredi | ab8d11b | 2005-09-06 15:18:24 -0700 | [diff] [blame] | 276 | { |
David Howells | c69e8d9 | 2008-11-14 10:39:19 +1100 | [diff] [blame] | 277 | const struct cred *cred = current_cred(), *tcred; |
Eric W. Biederman | bfedb58 | 2016-10-13 21:23:16 -0500 | [diff] [blame] | 278 | struct mm_struct *mm; |
Jann Horn | caaee62 | 2016-01-20 15:00:04 -0800 | [diff] [blame] | 279 | kuid_t caller_uid; |
| 280 | kgid_t caller_gid; |
| 281 | |
| 282 | if (!(mode & PTRACE_MODE_FSCREDS) == !(mode & PTRACE_MODE_REALCREDS)) { |
| 283 | WARN(1, "denying ptrace access check without PTRACE_MODE_*CREDS\n"); |
| 284 | return -EPERM; |
| 285 | } |
David Howells | b6dff3e | 2008-11-14 10:39:16 +1100 | [diff] [blame] | 286 | |
Eric W. Biederman | df26c40 | 2006-06-26 00:25:59 -0700 | [diff] [blame] | 287 | /* May we inspect the given task? |
| 288 | * This check is used both for attaching with ptrace |
| 289 | * and for allowing access to sensitive information in /proc. |
| 290 | * |
| 291 | * ptrace_attach denies several cases that /proc allows |
| 292 | * because setting up the necessary parent/child relationship |
| 293 | * or halting the specified task is impossible. |
| 294 | */ |
Jann Horn | caaee62 | 2016-01-20 15:00:04 -0800 | [diff] [blame] | 295 | |
Eric W. Biederman | df26c40 | 2006-06-26 00:25:59 -0700 | [diff] [blame] | 296 | /* Don't let security modules deny introspection */ |
Mark Grondona | 73af963 | 2013-09-11 14:24:31 -0700 | [diff] [blame] | 297 | if (same_thread_group(task, current)) |
Eric W. Biederman | df26c40 | 2006-06-26 00:25:59 -0700 | [diff] [blame] | 298 | return 0; |
David Howells | c69e8d9 | 2008-11-14 10:39:19 +1100 | [diff] [blame] | 299 | rcu_read_lock(); |
Jann Horn | caaee62 | 2016-01-20 15:00:04 -0800 | [diff] [blame] | 300 | if (mode & PTRACE_MODE_FSCREDS) { |
| 301 | caller_uid = cred->fsuid; |
| 302 | caller_gid = cred->fsgid; |
| 303 | } else { |
| 304 | /* |
| 305 | * Using the euid would make more sense here, but something |
| 306 | * in userland might rely on the old behavior, and this |
| 307 | * shouldn't be a security problem since |
| 308 | * PTRACE_MODE_REALCREDS implies that the caller explicitly |
| 309 | * used a syscall that requests access to another process |
| 310 | * (and not a filesystem syscall to procfs). |
| 311 | */ |
| 312 | caller_uid = cred->uid; |
| 313 | caller_gid = cred->gid; |
| 314 | } |
David Howells | c69e8d9 | 2008-11-14 10:39:19 +1100 | [diff] [blame] | 315 | tcred = __task_cred(task); |
Jann Horn | caaee62 | 2016-01-20 15:00:04 -0800 | [diff] [blame] | 316 | if (uid_eq(caller_uid, tcred->euid) && |
| 317 | uid_eq(caller_uid, tcred->suid) && |
| 318 | uid_eq(caller_uid, tcred->uid) && |
| 319 | gid_eq(caller_gid, tcred->egid) && |
| 320 | gid_eq(caller_gid, tcred->sgid) && |
| 321 | gid_eq(caller_gid, tcred->gid)) |
Serge E. Hallyn | 8409cca | 2011-03-23 16:43:20 -0700 | [diff] [blame] | 322 | goto ok; |
Mickaël Salaün | cf23705 | 2020-10-30 13:38:48 +0100 | [diff] [blame] | 323 | if (ptrace_has_cap(tcred->user_ns, mode)) |
Serge E. Hallyn | 8409cca | 2011-03-23 16:43:20 -0700 | [diff] [blame] | 324 | goto ok; |
| 325 | rcu_read_unlock(); |
| 326 | return -EPERM; |
| 327 | ok: |
David Howells | c69e8d9 | 2008-11-14 10:39:19 +1100 | [diff] [blame] | 328 | rcu_read_unlock(); |
Jann Horn | f6581f5b | 2019-05-29 13:31:57 +0200 | [diff] [blame] | 329 | /* |
| 330 | * If a task drops privileges and becomes nondumpable (through a syscall |
| 331 | * like setresuid()) while we are trying to access it, we must ensure |
| 332 | * that the dumpability is read after the credentials; otherwise, |
| 333 | * we may be able to attach to a task that we shouldn't be able to |
| 334 | * attach to (as if the task had dropped privileges without becoming |
| 335 | * nondumpable). |
| 336 | * Pairs with a write barrier in commit_creds(). |
| 337 | */ |
| 338 | smp_rmb(); |
Eric W. Biederman | bfedb58 | 2016-10-13 21:23:16 -0500 | [diff] [blame] | 339 | mm = task->mm; |
| 340 | if (mm && |
| 341 | ((get_dumpable(mm) != SUID_DUMP_USER) && |
Mickaël Salaün | cf23705 | 2020-10-30 13:38:48 +0100 | [diff] [blame] | 342 | !ptrace_has_cap(mm->user_ns, mode))) |
Eric W. Biederman | bfedb58 | 2016-10-13 21:23:16 -0500 | [diff] [blame] | 343 | return -EPERM; |
Miklos Szeredi | ab8d11b | 2005-09-06 15:18:24 -0700 | [diff] [blame] | 344 | |
Ingo Molnar | 9e48858 | 2009-05-07 19:26:19 +1000 | [diff] [blame] | 345 | return security_ptrace_access_check(task, mode); |
Miklos Szeredi | ab8d11b | 2005-09-06 15:18:24 -0700 | [diff] [blame] | 346 | } |
| 347 | |
Stephen Smalley | 006ebb4 | 2008-05-19 08:32:49 -0400 | [diff] [blame] | 348 | bool ptrace_may_access(struct task_struct *task, unsigned int mode) |
Miklos Szeredi | ab8d11b | 2005-09-06 15:18:24 -0700 | [diff] [blame] | 349 | { |
| 350 | int err; |
| 351 | task_lock(task); |
Stephen Smalley | 006ebb4 | 2008-05-19 08:32:49 -0400 | [diff] [blame] | 352 | err = __ptrace_may_access(task, mode); |
Miklos Szeredi | ab8d11b | 2005-09-06 15:18:24 -0700 | [diff] [blame] | 353 | task_unlock(task); |
Roland McGrath | 3a70970 | 2009-04-07 23:21:06 -0700 | [diff] [blame] | 354 | return !err; |
Miklos Szeredi | ab8d11b | 2005-09-06 15:18:24 -0700 | [diff] [blame] | 355 | } |
| 356 | |
Tejun Heo | 3544d72 | 2011-06-14 11:20:15 +0200 | [diff] [blame] | 357 | static int ptrace_attach(struct task_struct *task, long request, |
Denys Vlasenko | aa9147c | 2012-03-23 15:02:42 -0700 | [diff] [blame] | 358 | unsigned long addr, |
Tejun Heo | 3544d72 | 2011-06-14 11:20:15 +0200 | [diff] [blame] | 359 | unsigned long flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 360 | { |
Tejun Heo | 3544d72 | 2011-06-14 11:20:15 +0200 | [diff] [blame] | 361 | bool seize = (request == PTRACE_SEIZE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 362 | int retval; |
Linus Torvalds | f5b40e3 | 2006-05-07 10:49:33 -0700 | [diff] [blame] | 363 | |
Tejun Heo | 3544d72 | 2011-06-14 11:20:15 +0200 | [diff] [blame] | 364 | retval = -EIO; |
Denys Vlasenko | aa9147c | 2012-03-23 15:02:42 -0700 | [diff] [blame] | 365 | if (seize) { |
| 366 | if (addr != 0) |
| 367 | goto out; |
Denys Vlasenko | aa9147c | 2012-03-23 15:02:42 -0700 | [diff] [blame] | 368 | if (flags & ~(unsigned long)PTRACE_O_MASK) |
| 369 | goto out; |
| 370 | flags = PT_PTRACED | PT_SEIZED | (flags << PT_OPT_FLAG_SHIFT); |
| 371 | } else { |
| 372 | flags = PT_PTRACED; |
| 373 | } |
Tejun Heo | 3544d72 | 2011-06-14 11:20:15 +0200 | [diff] [blame] | 374 | |
Al Viro | a5cb013 | 2007-03-20 13:58:35 -0400 | [diff] [blame] | 375 | audit_ptrace(task); |
| 376 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 377 | retval = -EPERM; |
Oleg Nesterov | b79b7ba | 2009-06-17 16:27:31 -0700 | [diff] [blame] | 378 | if (unlikely(task->flags & PF_KTHREAD)) |
| 379 | goto out; |
Pavel Emelyanov | bac0abd | 2007-10-18 23:40:18 -0700 | [diff] [blame] | 380 | if (same_thread_group(task, current)) |
Linus Torvalds | f5b40e3 | 2006-05-07 10:49:33 -0700 | [diff] [blame] | 381 | goto out; |
| 382 | |
Oleg Nesterov | f2f0b00 | 2009-06-17 16:27:32 -0700 | [diff] [blame] | 383 | /* |
| 384 | * Protect exec's credential calculations against our interference; |
Denys Vlasenko | 86b6c1f | 2012-03-23 15:02:41 -0700 | [diff] [blame] | 385 | * SUID, SGID and LSM creds get determined differently |
David Howells | 5e751e9 | 2009-05-08 13:55:22 +0100 | [diff] [blame] | 386 | * under ptrace. |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 387 | */ |
Oleg Nesterov | 793285f | 2009-07-05 12:08:26 -0700 | [diff] [blame] | 388 | retval = -ERESTARTNOINTR; |
KOSAKI Motohiro | 9b1bf12 | 2010-10-27 15:34:08 -0700 | [diff] [blame] | 389 | if (mutex_lock_interruptible(&task->signal->cred_guard_mutex)) |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 390 | goto out; |
Oleg Nesterov | 4b105cb | 2009-06-17 16:27:33 -0700 | [diff] [blame] | 391 | |
Linus Torvalds | f5b40e3 | 2006-05-07 10:49:33 -0700 | [diff] [blame] | 392 | task_lock(task); |
Jann Horn | caaee62 | 2016-01-20 15:00:04 -0800 | [diff] [blame] | 393 | retval = __ptrace_may_access(task, PTRACE_MODE_ATTACH_REALCREDS); |
Oleg Nesterov | 4b105cb | 2009-06-17 16:27:33 -0700 | [diff] [blame] | 394 | task_unlock(task); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 395 | if (retval) |
Oleg Nesterov | 4b105cb | 2009-06-17 16:27:33 -0700 | [diff] [blame] | 396 | goto unlock_creds; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 397 | |
Oleg Nesterov | 4b105cb | 2009-06-17 16:27:33 -0700 | [diff] [blame] | 398 | write_lock_irq(&tasklist_lock); |
Oleg Nesterov | b79b7ba | 2009-06-17 16:27:31 -0700 | [diff] [blame] | 399 | retval = -EPERM; |
| 400 | if (unlikely(task->exit_state)) |
Oleg Nesterov | 4b105cb | 2009-06-17 16:27:33 -0700 | [diff] [blame] | 401 | goto unlock_tasklist; |
Oleg Nesterov | f2f0b00 | 2009-06-17 16:27:32 -0700 | [diff] [blame] | 402 | if (task->ptrace) |
Oleg Nesterov | 4b105cb | 2009-06-17 16:27:33 -0700 | [diff] [blame] | 403 | goto unlock_tasklist; |
Oleg Nesterov | b79b7ba | 2009-06-17 16:27:31 -0700 | [diff] [blame] | 404 | |
Tejun Heo | 3544d72 | 2011-06-14 11:20:15 +0200 | [diff] [blame] | 405 | if (seize) |
Denys Vlasenko | aa9147c | 2012-03-23 15:02:42 -0700 | [diff] [blame] | 406 | flags |= PT_SEIZED; |
Denys Vlasenko | aa9147c | 2012-03-23 15:02:42 -0700 | [diff] [blame] | 407 | task->ptrace = flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 408 | |
Eric W. Biederman | c70d9d8 | 2017-05-22 15:40:12 -0500 | [diff] [blame] | 409 | ptrace_link(task, current); |
Tejun Heo | 3544d72 | 2011-06-14 11:20:15 +0200 | [diff] [blame] | 410 | |
| 411 | /* SEIZE doesn't trap tracee on attach */ |
| 412 | if (!seize) |
Eric W. Biederman | 079b22d | 2018-09-03 10:32:52 +0200 | [diff] [blame] | 413 | send_sig_info(SIGSTOP, SEND_SIG_PRIV, task); |
Oleg Nesterov | b79b7ba | 2009-06-17 16:27:31 -0700 | [diff] [blame] | 414 | |
Tejun Heo | d79fdd6 | 2011-03-23 10:37:00 +0100 | [diff] [blame] | 415 | spin_lock(&task->sighand->siglock); |
| 416 | |
| 417 | /* |
Tejun Heo | 73ddff2 | 2011-06-14 11:20:14 +0200 | [diff] [blame] | 418 | * If the task is already STOPPED, set JOBCTL_TRAP_STOP and |
Tejun Heo | d79fdd6 | 2011-03-23 10:37:00 +0100 | [diff] [blame] | 419 | * TRAPPING, and kick it so that it transits to TRACED. TRAPPING |
| 420 | * will be cleared if the child completes the transition or any |
| 421 | * event which clears the group stop states happens. We'll wait |
| 422 | * for the transition to complete before returning from this |
| 423 | * function. |
| 424 | * |
| 425 | * This hides STOPPED -> RUNNING -> TRACED transition from the |
| 426 | * attaching thread but a different thread in the same group can |
| 427 | * still observe the transient RUNNING state. IOW, if another |
| 428 | * thread's WNOHANG wait(2) on the stopped tracee races against |
| 429 | * ATTACH, the wait(2) may fail due to the transient RUNNING. |
| 430 | * |
| 431 | * The following task_is_stopped() test is safe as both transitions |
| 432 | * in and out of STOPPED are protected by siglock. |
| 433 | */ |
Tejun Heo | 7dd3db5 | 2011-06-02 11:14:00 +0200 | [diff] [blame] | 434 | if (task_is_stopped(task) && |
Tejun Heo | 73ddff2 | 2011-06-14 11:20:14 +0200 | [diff] [blame] | 435 | task_set_jobctl_pending(task, JOBCTL_TRAP_STOP | JOBCTL_TRAPPING)) |
Oleg Nesterov | 910ffdb1 | 2013-01-21 20:47:41 +0100 | [diff] [blame] | 436 | signal_wake_up_state(task, __TASK_STOPPED); |
Tejun Heo | d79fdd6 | 2011-03-23 10:37:00 +0100 | [diff] [blame] | 437 | |
| 438 | spin_unlock(&task->sighand->siglock); |
| 439 | |
Oleg Nesterov | b79b7ba | 2009-06-17 16:27:31 -0700 | [diff] [blame] | 440 | retval = 0; |
Oleg Nesterov | 4b105cb | 2009-06-17 16:27:33 -0700 | [diff] [blame] | 441 | unlock_tasklist: |
| 442 | write_unlock_irq(&tasklist_lock); |
| 443 | unlock_creds: |
KOSAKI Motohiro | 9b1bf12 | 2010-10-27 15:34:08 -0700 | [diff] [blame] | 444 | mutex_unlock(&task->signal->cred_guard_mutex); |
Linus Torvalds | f5b40e3 | 2006-05-07 10:49:33 -0700 | [diff] [blame] | 445 | out: |
Vladimir Zapolskiy | f701e5b | 2011-07-15 20:45:18 +0300 | [diff] [blame] | 446 | if (!retval) { |
Oleg Nesterov | 7c3b00e | 2016-01-20 14:59:55 -0800 | [diff] [blame] | 447 | /* |
| 448 | * We do not bother to change retval or clear JOBCTL_TRAPPING |
| 449 | * if wait_on_bit() was interrupted by SIGKILL. The tracer will |
| 450 | * not return to user-mode, it will exit and clear this bit in |
| 451 | * __ptrace_unlink() if it wasn't already cleared by the tracee; |
| 452 | * and until then nobody can ptrace this task. |
| 453 | */ |
| 454 | wait_on_bit(&task->jobctl, JOBCTL_TRAPPING_BIT, TASK_KILLABLE); |
Vladimir Zapolskiy | f701e5b | 2011-07-15 20:45:18 +0300 | [diff] [blame] | 455 | proc_ptrace_connector(task, PTRACE_ATTACH); |
| 456 | } |
| 457 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 458 | return retval; |
| 459 | } |
| 460 | |
Oleg Nesterov | f2f0b00 | 2009-06-17 16:27:32 -0700 | [diff] [blame] | 461 | /** |
| 462 | * ptrace_traceme -- helper for PTRACE_TRACEME |
| 463 | * |
| 464 | * Performs checks and sets PT_PTRACED. |
| 465 | * Should be used by all ptrace implementations for PTRACE_TRACEME. |
| 466 | */ |
Linus Torvalds | e3e89cc | 2011-03-04 09:23:30 -0800 | [diff] [blame] | 467 | static int ptrace_traceme(void) |
Oleg Nesterov | f2f0b00 | 2009-06-17 16:27:32 -0700 | [diff] [blame] | 468 | { |
| 469 | int ret = -EPERM; |
| 470 | |
Oleg Nesterov | 4b105cb | 2009-06-17 16:27:33 -0700 | [diff] [blame] | 471 | write_lock_irq(&tasklist_lock); |
| 472 | /* Are we already being traced? */ |
Oleg Nesterov | f2f0b00 | 2009-06-17 16:27:32 -0700 | [diff] [blame] | 473 | if (!current->ptrace) { |
Oleg Nesterov | f2f0b00 | 2009-06-17 16:27:32 -0700 | [diff] [blame] | 474 | ret = security_ptrace_traceme(current->parent); |
Oleg Nesterov | f2f0b00 | 2009-06-17 16:27:32 -0700 | [diff] [blame] | 475 | /* |
| 476 | * Check PF_EXITING to ensure ->real_parent has not passed |
| 477 | * exit_ptrace(). Otherwise we don't report the error but |
| 478 | * pretend ->real_parent untraces us right after return. |
| 479 | */ |
| 480 | if (!ret && !(current->real_parent->flags & PF_EXITING)) { |
| 481 | current->ptrace = PT_PTRACED; |
Eric W. Biederman | c70d9d8 | 2017-05-22 15:40:12 -0500 | [diff] [blame] | 482 | ptrace_link(current, current->real_parent); |
Oleg Nesterov | f2f0b00 | 2009-06-17 16:27:32 -0700 | [diff] [blame] | 483 | } |
Oleg Nesterov | f2f0b00 | 2009-06-17 16:27:32 -0700 | [diff] [blame] | 484 | } |
Oleg Nesterov | 4b105cb | 2009-06-17 16:27:33 -0700 | [diff] [blame] | 485 | write_unlock_irq(&tasklist_lock); |
| 486 | |
Oleg Nesterov | f2f0b00 | 2009-06-17 16:27:32 -0700 | [diff] [blame] | 487 | return ret; |
| 488 | } |
| 489 | |
Oleg Nesterov | 39c626a | 2009-04-02 16:58:18 -0700 | [diff] [blame] | 490 | /* |
| 491 | * Called with irqs disabled, returns true if childs should reap themselves. |
| 492 | */ |
| 493 | static int ignoring_children(struct sighand_struct *sigh) |
| 494 | { |
| 495 | int ret; |
| 496 | spin_lock(&sigh->siglock); |
| 497 | ret = (sigh->action[SIGCHLD-1].sa.sa_handler == SIG_IGN) || |
| 498 | (sigh->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDWAIT); |
| 499 | spin_unlock(&sigh->siglock); |
| 500 | return ret; |
| 501 | } |
| 502 | |
| 503 | /* |
| 504 | * Called with tasklist_lock held for writing. |
| 505 | * Unlink a traced task, and clean it up if it was a traced zombie. |
| 506 | * Return true if it needs to be reaped with release_task(). |
| 507 | * (We can't call release_task() here because we already hold tasklist_lock.) |
| 508 | * |
| 509 | * If it's a zombie, our attachedness prevented normal parent notification |
| 510 | * or self-reaping. Do notification now if it would have happened earlier. |
| 511 | * If it should reap itself, return true. |
| 512 | * |
Oleg Nesterov | a7f0765 | 2009-09-23 15:56:44 -0700 | [diff] [blame] | 513 | * If it's our own child, there is no notification to do. But if our normal |
| 514 | * children self-reap, then this child was prevented by ptrace and we must |
| 515 | * reap it now, in that case we must also wake up sub-threads sleeping in |
| 516 | * do_wait(). |
Oleg Nesterov | 39c626a | 2009-04-02 16:58:18 -0700 | [diff] [blame] | 517 | */ |
| 518 | static bool __ptrace_detach(struct task_struct *tracer, struct task_struct *p) |
| 519 | { |
Oleg Nesterov | 9843a1e | 2011-06-22 23:08:53 +0200 | [diff] [blame] | 520 | bool dead; |
| 521 | |
Oleg Nesterov | 39c626a | 2009-04-02 16:58:18 -0700 | [diff] [blame] | 522 | __ptrace_unlink(p); |
| 523 | |
Oleg Nesterov | 9843a1e | 2011-06-22 23:08:53 +0200 | [diff] [blame] | 524 | if (p->exit_state != EXIT_ZOMBIE) |
| 525 | return false; |
| 526 | |
| 527 | dead = !thread_group_leader(p); |
| 528 | |
| 529 | if (!dead && thread_group_empty(p)) { |
| 530 | if (!same_thread_group(p->real_parent, tracer)) |
| 531 | dead = do_notify_parent(p, p->exit_signal); |
| 532 | else if (ignoring_children(tracer->sighand)) { |
| 533 | __wake_up_parent(p, tracer); |
Oleg Nesterov | 9843a1e | 2011-06-22 23:08:53 +0200 | [diff] [blame] | 534 | dead = true; |
Oleg Nesterov | 39c626a | 2009-04-02 16:58:18 -0700 | [diff] [blame] | 535 | } |
| 536 | } |
Oleg Nesterov | 9843a1e | 2011-06-22 23:08:53 +0200 | [diff] [blame] | 537 | /* Mark it as in the process of being reaped. */ |
| 538 | if (dead) |
| 539 | p->exit_state = EXIT_DEAD; |
| 540 | return dead; |
Oleg Nesterov | 39c626a | 2009-04-02 16:58:18 -0700 | [diff] [blame] | 541 | } |
| 542 | |
Linus Torvalds | e3e89cc | 2011-03-04 09:23:30 -0800 | [diff] [blame] | 543 | static int ptrace_detach(struct task_struct *child, unsigned int data) |
Oleg Nesterov | 5ecfbae | 2006-02-15 22:50:10 +0300 | [diff] [blame] | 544 | { |
| 545 | if (!valid_signal(data)) |
| 546 | return -EIO; |
| 547 | |
| 548 | /* Architecture-specific hardware disable .. */ |
| 549 | ptrace_disable(child); |
| 550 | |
Oleg Nesterov | 95c3eb7 | 2009-04-02 16:58:11 -0700 | [diff] [blame] | 551 | write_lock_irq(&tasklist_lock); |
Oleg Nesterov | 39c626a | 2009-04-02 16:58:18 -0700 | [diff] [blame] | 552 | /* |
Oleg Nesterov | 64a4096 | 2015-04-16 12:47:32 -0700 | [diff] [blame] | 553 | * We rely on ptrace_freeze_traced(). It can't be killed and |
| 554 | * untraced by another thread, it can't be a zombie. |
Oleg Nesterov | 39c626a | 2009-04-02 16:58:18 -0700 | [diff] [blame] | 555 | */ |
Oleg Nesterov | 64a4096 | 2015-04-16 12:47:32 -0700 | [diff] [blame] | 556 | WARN_ON(!child->ptrace || child->exit_state); |
| 557 | /* |
| 558 | * tasklist_lock avoids the race with wait_task_stopped(), see |
| 559 | * the comment in ptrace_resume(). |
| 560 | */ |
| 561 | child->exit_code = data; |
| 562 | __ptrace_detach(current, child); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 563 | write_unlock_irq(&tasklist_lock); |
| 564 | |
Vladimir Zapolskiy | f701e5b | 2011-07-15 20:45:18 +0300 | [diff] [blame] | 565 | proc_ptrace_connector(child, PTRACE_DETACH); |
Oleg Nesterov | 4576145 | 2009-04-02 16:58:14 -0700 | [diff] [blame] | 566 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 567 | return 0; |
| 568 | } |
| 569 | |
Oleg Nesterov | 39c626a | 2009-04-02 16:58:18 -0700 | [diff] [blame] | 570 | /* |
Oleg Nesterov | c7e49c1 | 2010-08-10 18:03:07 -0700 | [diff] [blame] | 571 | * Detach all tasks we were using ptrace on. Called with tasklist held |
Oleg Nesterov | 7c8bd23 | 2014-12-10 15:45:33 -0800 | [diff] [blame] | 572 | * for writing. |
Oleg Nesterov | 39c626a | 2009-04-02 16:58:18 -0700 | [diff] [blame] | 573 | */ |
Oleg Nesterov | 7c8bd23 | 2014-12-10 15:45:33 -0800 | [diff] [blame] | 574 | void exit_ptrace(struct task_struct *tracer, struct list_head *dead) |
Oleg Nesterov | 39c626a | 2009-04-02 16:58:18 -0700 | [diff] [blame] | 575 | { |
| 576 | struct task_struct *p, *n; |
Oleg Nesterov | c7e49c1 | 2010-08-10 18:03:07 -0700 | [diff] [blame] | 577 | |
Oleg Nesterov | 39c626a | 2009-04-02 16:58:18 -0700 | [diff] [blame] | 578 | list_for_each_entry_safe(p, n, &tracer->ptraced, ptrace_entry) { |
Oleg Nesterov | 992fb6e | 2012-12-17 16:03:07 -0800 | [diff] [blame] | 579 | if (unlikely(p->ptrace & PT_EXITKILL)) |
Eric W. Biederman | 079b22d | 2018-09-03 10:32:52 +0200 | [diff] [blame] | 580 | send_sig_info(SIGKILL, SEND_SIG_PRIV, p); |
Oleg Nesterov | 992fb6e | 2012-12-17 16:03:07 -0800 | [diff] [blame] | 581 | |
Oleg Nesterov | 39c626a | 2009-04-02 16:58:18 -0700 | [diff] [blame] | 582 | if (__ptrace_detach(tracer, p)) |
Oleg Nesterov | 7c8bd23 | 2014-12-10 15:45:33 -0800 | [diff] [blame] | 583 | list_add(&p->ptrace_entry, dead); |
Oleg Nesterov | 39c626a | 2009-04-02 16:58:18 -0700 | [diff] [blame] | 584 | } |
Oleg Nesterov | 39c626a | 2009-04-02 16:58:18 -0700 | [diff] [blame] | 585 | } |
| 586 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 587 | int ptrace_readdata(struct task_struct *tsk, unsigned long src, char __user *dst, int len) |
| 588 | { |
| 589 | int copied = 0; |
| 590 | |
| 591 | while (len > 0) { |
| 592 | char buf[128]; |
| 593 | int this_len, retval; |
| 594 | |
| 595 | this_len = (len > sizeof(buf)) ? sizeof(buf) : len; |
Eric W. Biederman | 84d77d3 | 2016-11-22 12:06:50 -0600 | [diff] [blame] | 596 | retval = ptrace_access_vm(tsk, src, buf, this_len, FOLL_FORCE); |
| 597 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 598 | if (!retval) { |
| 599 | if (copied) |
| 600 | break; |
| 601 | return -EIO; |
| 602 | } |
| 603 | if (copy_to_user(dst, buf, retval)) |
| 604 | return -EFAULT; |
| 605 | copied += retval; |
| 606 | src += retval; |
| 607 | dst += retval; |
Roland McGrath | 3a70970 | 2009-04-07 23:21:06 -0700 | [diff] [blame] | 608 | len -= retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 609 | } |
| 610 | return copied; |
| 611 | } |
| 612 | |
| 613 | int ptrace_writedata(struct task_struct *tsk, char __user *src, unsigned long dst, int len) |
| 614 | { |
| 615 | int copied = 0; |
| 616 | |
| 617 | while (len > 0) { |
| 618 | char buf[128]; |
| 619 | int this_len, retval; |
| 620 | |
| 621 | this_len = (len > sizeof(buf)) ? sizeof(buf) : len; |
| 622 | if (copy_from_user(buf, src, this_len)) |
| 623 | return -EFAULT; |
Eric W. Biederman | 84d77d3 | 2016-11-22 12:06:50 -0600 | [diff] [blame] | 624 | retval = ptrace_access_vm(tsk, dst, buf, this_len, |
Lorenzo Stoakes | f307ab6 | 2016-10-13 01:20:20 +0100 | [diff] [blame] | 625 | FOLL_FORCE | FOLL_WRITE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 626 | if (!retval) { |
| 627 | if (copied) |
| 628 | break; |
| 629 | return -EIO; |
| 630 | } |
| 631 | copied += retval; |
| 632 | src += retval; |
| 633 | dst += retval; |
Roland McGrath | 3a70970 | 2009-04-07 23:21:06 -0700 | [diff] [blame] | 634 | len -= retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 635 | } |
| 636 | return copied; |
| 637 | } |
| 638 | |
Namhyung Kim | 4abf986 | 2010-10-27 15:33:45 -0700 | [diff] [blame] | 639 | static int ptrace_setoptions(struct task_struct *child, unsigned long data) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 640 | { |
Denys Vlasenko | 86b6c1f | 2012-03-23 15:02:41 -0700 | [diff] [blame] | 641 | unsigned flags; |
| 642 | |
Denys Vlasenko | 8c5cf9e | 2012-03-23 15:02:40 -0700 | [diff] [blame] | 643 | if (data & ~(unsigned long)PTRACE_O_MASK) |
| 644 | return -EINVAL; |
| 645 | |
Tycho Andersen | 13c4a90 | 2015-06-13 09:02:48 -0600 | [diff] [blame] | 646 | if (unlikely(data & PTRACE_O_SUSPEND_SECCOMP)) { |
Masahiro Yamada | 97f2645 | 2016-08-03 13:45:50 -0700 | [diff] [blame] | 647 | if (!IS_ENABLED(CONFIG_CHECKPOINT_RESTORE) || |
| 648 | !IS_ENABLED(CONFIG_SECCOMP)) |
Tycho Andersen | 13c4a90 | 2015-06-13 09:02:48 -0600 | [diff] [blame] | 649 | return -EINVAL; |
| 650 | |
| 651 | if (!capable(CAP_SYS_ADMIN)) |
| 652 | return -EPERM; |
| 653 | |
| 654 | if (seccomp_mode(¤t->seccomp) != SECCOMP_MODE_DISABLED || |
| 655 | current->ptrace & PT_SUSPEND_SECCOMP) |
| 656 | return -EPERM; |
| 657 | } |
| 658 | |
Denys Vlasenko | 86b6c1f | 2012-03-23 15:02:41 -0700 | [diff] [blame] | 659 | /* Avoid intermediate state when all opts are cleared */ |
| 660 | flags = child->ptrace; |
| 661 | flags &= ~(PTRACE_O_MASK << PT_OPT_FLAG_SHIFT); |
| 662 | flags |= (data << PT_OPT_FLAG_SHIFT); |
| 663 | child->ptrace = flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 664 | |
Denys Vlasenko | 8c5cf9e | 2012-03-23 15:02:40 -0700 | [diff] [blame] | 665 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 666 | } |
| 667 | |
Eric W. Biederman | ae7795b | 2018-09-25 11:27:20 +0200 | [diff] [blame] | 668 | static int ptrace_getsiginfo(struct task_struct *child, kernel_siginfo_t *info) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 669 | { |
Oleg Nesterov | e496125 | 2009-06-17 16:27:36 -0700 | [diff] [blame] | 670 | unsigned long flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 671 | int error = -ESRCH; |
| 672 | |
Oleg Nesterov | e496125 | 2009-06-17 16:27:36 -0700 | [diff] [blame] | 673 | if (lock_task_sighand(child, &flags)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 674 | error = -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 675 | if (likely(child->last_siginfo != NULL)) { |
Eric W. Biederman | 0752d7bf | 2017-07-24 15:08:16 -0500 | [diff] [blame] | 676 | copy_siginfo(info, child->last_siginfo); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 677 | error = 0; |
| 678 | } |
Oleg Nesterov | e496125 | 2009-06-17 16:27:36 -0700 | [diff] [blame] | 679 | unlock_task_sighand(child, &flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 680 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 681 | return error; |
| 682 | } |
| 683 | |
Eric W. Biederman | ae7795b | 2018-09-25 11:27:20 +0200 | [diff] [blame] | 684 | static int ptrace_setsiginfo(struct task_struct *child, const kernel_siginfo_t *info) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 685 | { |
Oleg Nesterov | e496125 | 2009-06-17 16:27:36 -0700 | [diff] [blame] | 686 | unsigned long flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 687 | int error = -ESRCH; |
| 688 | |
Oleg Nesterov | e496125 | 2009-06-17 16:27:36 -0700 | [diff] [blame] | 689 | if (lock_task_sighand(child, &flags)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 690 | error = -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 691 | if (likely(child->last_siginfo != NULL)) { |
Eric W. Biederman | 0752d7bf | 2017-07-24 15:08:16 -0500 | [diff] [blame] | 692 | copy_siginfo(child->last_siginfo, info); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 693 | error = 0; |
| 694 | } |
Oleg Nesterov | e496125 | 2009-06-17 16:27:36 -0700 | [diff] [blame] | 695 | unlock_task_sighand(child, &flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 696 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 697 | return error; |
| 698 | } |
| 699 | |
Andrey Vagin | 84c751b | 2013-04-30 15:27:59 -0700 | [diff] [blame] | 700 | static int ptrace_peek_siginfo(struct task_struct *child, |
| 701 | unsigned long addr, |
| 702 | unsigned long data) |
| 703 | { |
| 704 | struct ptrace_peeksiginfo_args arg; |
| 705 | struct sigpending *pending; |
| 706 | struct sigqueue *q; |
| 707 | int ret, i; |
| 708 | |
| 709 | ret = copy_from_user(&arg, (void __user *) addr, |
| 710 | sizeof(struct ptrace_peeksiginfo_args)); |
| 711 | if (ret) |
| 712 | return -EFAULT; |
| 713 | |
| 714 | if (arg.flags & ~PTRACE_PEEKSIGINFO_SHARED) |
| 715 | return -EINVAL; /* unknown flags */ |
| 716 | |
| 717 | if (arg.nr < 0) |
| 718 | return -EINVAL; |
| 719 | |
Eric W. Biederman | f6e2aa9 | 2019-05-28 18:46:37 -0500 | [diff] [blame] | 720 | /* Ensure arg.off fits in an unsigned long */ |
| 721 | if (arg.off > ULONG_MAX) |
| 722 | return 0; |
| 723 | |
Andrey Vagin | 84c751b | 2013-04-30 15:27:59 -0700 | [diff] [blame] | 724 | if (arg.flags & PTRACE_PEEKSIGINFO_SHARED) |
| 725 | pending = &child->signal->shared_pending; |
| 726 | else |
| 727 | pending = &child->pending; |
| 728 | |
| 729 | for (i = 0; i < arg.nr; ) { |
Eric W. Biederman | ae7795b | 2018-09-25 11:27:20 +0200 | [diff] [blame] | 730 | kernel_siginfo_t info; |
Eric W. Biederman | f6e2aa9 | 2019-05-28 18:46:37 -0500 | [diff] [blame] | 731 | unsigned long off = arg.off + i; |
| 732 | bool found = false; |
Andrey Vagin | 84c751b | 2013-04-30 15:27:59 -0700 | [diff] [blame] | 733 | |
| 734 | spin_lock_irq(&child->sighand->siglock); |
| 735 | list_for_each_entry(q, &pending->list, list) { |
| 736 | if (!off--) { |
Eric W. Biederman | f6e2aa9 | 2019-05-28 18:46:37 -0500 | [diff] [blame] | 737 | found = true; |
Andrey Vagin | 84c751b | 2013-04-30 15:27:59 -0700 | [diff] [blame] | 738 | copy_siginfo(&info, &q->info); |
| 739 | break; |
| 740 | } |
| 741 | } |
| 742 | spin_unlock_irq(&child->sighand->siglock); |
| 743 | |
Eric W. Biederman | f6e2aa9 | 2019-05-28 18:46:37 -0500 | [diff] [blame] | 744 | if (!found) /* beyond the end of the list */ |
Andrey Vagin | 84c751b | 2013-04-30 15:27:59 -0700 | [diff] [blame] | 745 | break; |
| 746 | |
| 747 | #ifdef CONFIG_COMPAT |
Andy Lutomirski | 5c46521 | 2016-03-22 14:24:55 -0700 | [diff] [blame] | 748 | if (unlikely(in_compat_syscall())) { |
Andrey Vagin | 84c751b | 2013-04-30 15:27:59 -0700 | [diff] [blame] | 749 | compat_siginfo_t __user *uinfo = compat_ptr(data); |
| 750 | |
Eric W. Biederman | cc73152 | 2017-07-16 22:36:59 -0500 | [diff] [blame] | 751 | if (copy_siginfo_to_user32(uinfo, &info)) { |
Mathieu Desnoyers | 706b23b | 2013-06-28 09:49:46 -0400 | [diff] [blame] | 752 | ret = -EFAULT; |
| 753 | break; |
| 754 | } |
| 755 | |
Andrey Vagin | 84c751b | 2013-04-30 15:27:59 -0700 | [diff] [blame] | 756 | } else |
| 757 | #endif |
| 758 | { |
| 759 | siginfo_t __user *uinfo = (siginfo_t __user *) data; |
| 760 | |
Eric W. Biederman | cc73152 | 2017-07-16 22:36:59 -0500 | [diff] [blame] | 761 | if (copy_siginfo_to_user(uinfo, &info)) { |
Mathieu Desnoyers | 706b23b | 2013-06-28 09:49:46 -0400 | [diff] [blame] | 762 | ret = -EFAULT; |
| 763 | break; |
| 764 | } |
Andrey Vagin | 84c751b | 2013-04-30 15:27:59 -0700 | [diff] [blame] | 765 | } |
| 766 | |
| 767 | data += sizeof(siginfo_t); |
| 768 | i++; |
| 769 | |
| 770 | if (signal_pending(current)) |
| 771 | break; |
| 772 | |
| 773 | cond_resched(); |
| 774 | } |
| 775 | |
| 776 | if (i > 0) |
| 777 | return i; |
| 778 | |
| 779 | return ret; |
| 780 | } |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 781 | |
| 782 | #ifdef PTRACE_SINGLESTEP |
| 783 | #define is_singlestep(request) ((request) == PTRACE_SINGLESTEP) |
| 784 | #else |
| 785 | #define is_singlestep(request) 0 |
| 786 | #endif |
| 787 | |
Roland McGrath | 5b88abb | 2008-01-30 13:30:53 +0100 | [diff] [blame] | 788 | #ifdef PTRACE_SINGLEBLOCK |
| 789 | #define is_singleblock(request) ((request) == PTRACE_SINGLEBLOCK) |
| 790 | #else |
| 791 | #define is_singleblock(request) 0 |
| 792 | #endif |
| 793 | |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 794 | #ifdef PTRACE_SYSEMU |
| 795 | #define is_sysemu_singlestep(request) ((request) == PTRACE_SYSEMU_SINGLESTEP) |
| 796 | #else |
| 797 | #define is_sysemu_singlestep(request) 0 |
| 798 | #endif |
| 799 | |
Namhyung Kim | 4abf986 | 2010-10-27 15:33:45 -0700 | [diff] [blame] | 800 | static int ptrace_resume(struct task_struct *child, long request, |
| 801 | unsigned long data) |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 802 | { |
Oleg Nesterov | b72c186 | 2015-04-16 12:47:29 -0700 | [diff] [blame] | 803 | bool need_siglock; |
| 804 | |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 805 | if (!valid_signal(data)) |
| 806 | return -EIO; |
| 807 | |
| 808 | if (request == PTRACE_SYSCALL) |
Gabriel Krisman Bertazi | 64c19ba | 2020-11-16 12:42:02 -0500 | [diff] [blame] | 809 | set_task_syscall_work(child, SYSCALL_TRACE); |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 810 | else |
Gabriel Krisman Bertazi | 64c19ba | 2020-11-16 12:42:02 -0500 | [diff] [blame] | 811 | clear_task_syscall_work(child, SYSCALL_TRACE); |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 812 | |
Gabriel Krisman Bertazi | 64eb35f | 2020-11-16 12:42:03 -0500 | [diff] [blame] | 813 | #if defined(CONFIG_GENERIC_ENTRY) || defined(TIF_SYSCALL_EMU) |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 814 | if (request == PTRACE_SYSEMU || request == PTRACE_SYSEMU_SINGLESTEP) |
Gabriel Krisman Bertazi | 64eb35f | 2020-11-16 12:42:03 -0500 | [diff] [blame] | 815 | set_task_syscall_work(child, SYSCALL_EMU); |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 816 | else |
Gabriel Krisman Bertazi | 64eb35f | 2020-11-16 12:42:03 -0500 | [diff] [blame] | 817 | clear_task_syscall_work(child, SYSCALL_EMU); |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 818 | #endif |
| 819 | |
Roland McGrath | 5b88abb | 2008-01-30 13:30:53 +0100 | [diff] [blame] | 820 | if (is_singleblock(request)) { |
| 821 | if (unlikely(!arch_has_block_step())) |
| 822 | return -EIO; |
| 823 | user_enable_block_step(child); |
| 824 | } else if (is_singlestep(request) || is_sysemu_singlestep(request)) { |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 825 | if (unlikely(!arch_has_single_step())) |
| 826 | return -EIO; |
| 827 | user_enable_single_step(child); |
Roland McGrath | 3a70970 | 2009-04-07 23:21:06 -0700 | [diff] [blame] | 828 | } else { |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 829 | user_disable_single_step(child); |
Roland McGrath | 3a70970 | 2009-04-07 23:21:06 -0700 | [diff] [blame] | 830 | } |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 831 | |
Oleg Nesterov | b72c186 | 2015-04-16 12:47:29 -0700 | [diff] [blame] | 832 | /* |
| 833 | * Change ->exit_code and ->state under siglock to avoid the race |
| 834 | * with wait_task_stopped() in between; a non-zero ->exit_code will |
| 835 | * wrongly look like another report from tracee. |
| 836 | * |
| 837 | * Note that we need siglock even if ->exit_code == data and/or this |
| 838 | * status was not reported yet, the new status must not be cleared by |
| 839 | * wait_task_stopped() after resume. |
| 840 | * |
| 841 | * If data == 0 we do not care if wait_task_stopped() reports the old |
| 842 | * status and clears the code too; this can't race with the tracee, it |
| 843 | * takes siglock after resume. |
| 844 | */ |
| 845 | need_siglock = data && !thread_group_empty(current); |
| 846 | if (need_siglock) |
| 847 | spin_lock_irq(&child->sighand->siglock); |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 848 | child->exit_code = data; |
Oleg Nesterov | 0666fb5 | 2011-05-25 19:20:21 +0200 | [diff] [blame] | 849 | wake_up_state(child, __TASK_TRACED); |
Oleg Nesterov | b72c186 | 2015-04-16 12:47:29 -0700 | [diff] [blame] | 850 | if (need_siglock) |
| 851 | spin_unlock_irq(&child->sighand->siglock); |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 852 | |
| 853 | return 0; |
| 854 | } |
| 855 | |
Suresh Siddha | 2225a12 | 2010-02-11 11:51:00 -0800 | [diff] [blame] | 856 | #ifdef CONFIG_HAVE_ARCH_TRACEHOOK |
| 857 | |
| 858 | static const struct user_regset * |
| 859 | find_regset(const struct user_regset_view *view, unsigned int type) |
| 860 | { |
| 861 | const struct user_regset *regset; |
| 862 | int n; |
| 863 | |
| 864 | for (n = 0; n < view->n; ++n) { |
| 865 | regset = view->regsets + n; |
| 866 | if (regset->core_note_type == type) |
| 867 | return regset; |
| 868 | } |
| 869 | |
| 870 | return NULL; |
| 871 | } |
| 872 | |
| 873 | static int ptrace_regset(struct task_struct *task, int req, unsigned int type, |
| 874 | struct iovec *kiov) |
| 875 | { |
| 876 | const struct user_regset_view *view = task_user_regset_view(task); |
| 877 | const struct user_regset *regset = find_regset(view, type); |
| 878 | int regset_no; |
| 879 | |
| 880 | if (!regset || (kiov->iov_len % regset->size) != 0) |
Suresh Siddha | c6a0dd7 | 2010-02-22 14:51:32 -0800 | [diff] [blame] | 881 | return -EINVAL; |
Suresh Siddha | 2225a12 | 2010-02-11 11:51:00 -0800 | [diff] [blame] | 882 | |
| 883 | regset_no = regset - view->regsets; |
| 884 | kiov->iov_len = min(kiov->iov_len, |
| 885 | (__kernel_size_t) (regset->n * regset->size)); |
| 886 | |
| 887 | if (req == PTRACE_GETREGSET) |
| 888 | return copy_regset_to_user(task, view, regset_no, 0, |
| 889 | kiov->iov_len, kiov->iov_base); |
| 890 | else |
| 891 | return copy_regset_from_user(task, view, regset_no, 0, |
| 892 | kiov->iov_len, kiov->iov_base); |
| 893 | } |
| 894 | |
Josh Stone | e8440c14 | 2013-01-13 19:03:34 +0100 | [diff] [blame] | 895 | /* |
| 896 | * This is declared in linux/regset.h and defined in machine-dependent |
| 897 | * code. We put the export here, near the primary machine-neutral use, |
| 898 | * to ensure no machine forgets it. |
| 899 | */ |
| 900 | EXPORT_SYMBOL_GPL(task_user_regset_view); |
Elvira Khabirova | 201766a | 2019-07-16 16:29:42 -0700 | [diff] [blame] | 901 | |
| 902 | static unsigned long |
| 903 | ptrace_get_syscall_info_entry(struct task_struct *child, struct pt_regs *regs, |
| 904 | struct ptrace_syscall_info *info) |
| 905 | { |
| 906 | unsigned long args[ARRAY_SIZE(info->entry.args)]; |
| 907 | int i; |
| 908 | |
| 909 | info->op = PTRACE_SYSCALL_INFO_ENTRY; |
| 910 | info->entry.nr = syscall_get_nr(child, regs); |
| 911 | syscall_get_arguments(child, regs, args); |
| 912 | for (i = 0; i < ARRAY_SIZE(args); i++) |
| 913 | info->entry.args[i] = args[i]; |
| 914 | |
| 915 | /* args is the last field in struct ptrace_syscall_info.entry */ |
| 916 | return offsetofend(struct ptrace_syscall_info, entry.args); |
| 917 | } |
| 918 | |
| 919 | static unsigned long |
| 920 | ptrace_get_syscall_info_seccomp(struct task_struct *child, struct pt_regs *regs, |
| 921 | struct ptrace_syscall_info *info) |
| 922 | { |
| 923 | /* |
| 924 | * As struct ptrace_syscall_info.entry is currently a subset |
| 925 | * of struct ptrace_syscall_info.seccomp, it makes sense to |
| 926 | * initialize that subset using ptrace_get_syscall_info_entry(). |
| 927 | * This can be reconsidered in the future if these structures |
| 928 | * diverge significantly enough. |
| 929 | */ |
| 930 | ptrace_get_syscall_info_entry(child, regs, info); |
| 931 | info->op = PTRACE_SYSCALL_INFO_SECCOMP; |
| 932 | info->seccomp.ret_data = child->ptrace_message; |
| 933 | |
| 934 | /* ret_data is the last field in struct ptrace_syscall_info.seccomp */ |
| 935 | return offsetofend(struct ptrace_syscall_info, seccomp.ret_data); |
| 936 | } |
| 937 | |
| 938 | static unsigned long |
| 939 | ptrace_get_syscall_info_exit(struct task_struct *child, struct pt_regs *regs, |
| 940 | struct ptrace_syscall_info *info) |
| 941 | { |
| 942 | info->op = PTRACE_SYSCALL_INFO_EXIT; |
| 943 | info->exit.rval = syscall_get_error(child, regs); |
| 944 | info->exit.is_error = !!info->exit.rval; |
| 945 | if (!info->exit.is_error) |
| 946 | info->exit.rval = syscall_get_return_value(child, regs); |
| 947 | |
| 948 | /* is_error is the last field in struct ptrace_syscall_info.exit */ |
| 949 | return offsetofend(struct ptrace_syscall_info, exit.is_error); |
| 950 | } |
| 951 | |
| 952 | static int |
| 953 | ptrace_get_syscall_info(struct task_struct *child, unsigned long user_size, |
| 954 | void __user *datavp) |
| 955 | { |
| 956 | struct pt_regs *regs = task_pt_regs(child); |
| 957 | struct ptrace_syscall_info info = { |
| 958 | .op = PTRACE_SYSCALL_INFO_NONE, |
| 959 | .arch = syscall_get_arch(child), |
| 960 | .instruction_pointer = instruction_pointer(regs), |
| 961 | .stack_pointer = user_stack_pointer(regs), |
| 962 | }; |
| 963 | unsigned long actual_size = offsetof(struct ptrace_syscall_info, entry); |
| 964 | unsigned long write_size; |
| 965 | |
| 966 | /* |
| 967 | * This does not need lock_task_sighand() to access |
| 968 | * child->last_siginfo because ptrace_freeze_traced() |
| 969 | * called earlier by ptrace_check_attach() ensures that |
| 970 | * the tracee cannot go away and clear its last_siginfo. |
| 971 | */ |
| 972 | switch (child->last_siginfo ? child->last_siginfo->si_code : 0) { |
| 973 | case SIGTRAP | 0x80: |
| 974 | switch (child->ptrace_message) { |
| 975 | case PTRACE_EVENTMSG_SYSCALL_ENTRY: |
| 976 | actual_size = ptrace_get_syscall_info_entry(child, regs, |
| 977 | &info); |
| 978 | break; |
| 979 | case PTRACE_EVENTMSG_SYSCALL_EXIT: |
| 980 | actual_size = ptrace_get_syscall_info_exit(child, regs, |
| 981 | &info); |
| 982 | break; |
| 983 | } |
| 984 | break; |
| 985 | case SIGTRAP | (PTRACE_EVENT_SECCOMP << 8): |
| 986 | actual_size = ptrace_get_syscall_info_seccomp(child, regs, |
| 987 | &info); |
| 988 | break; |
| 989 | } |
| 990 | |
| 991 | write_size = min(actual_size, user_size); |
| 992 | return copy_to_user(datavp, &info, write_size) ? -EFAULT : actual_size; |
| 993 | } |
| 994 | #endif /* CONFIG_HAVE_ARCH_TRACEHOOK */ |
Suresh Siddha | 2225a12 | 2010-02-11 11:51:00 -0800 | [diff] [blame] | 995 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 996 | int ptrace_request(struct task_struct *child, long request, |
Namhyung Kim | 4abf986 | 2010-10-27 15:33:45 -0700 | [diff] [blame] | 997 | unsigned long addr, unsigned long data) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 998 | { |
Tejun Heo | fca26f2 | 2011-06-14 11:20:16 +0200 | [diff] [blame] | 999 | bool seized = child->ptrace & PT_SEIZED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1000 | int ret = -EIO; |
Eric W. Biederman | ae7795b | 2018-09-25 11:27:20 +0200 | [diff] [blame] | 1001 | kernel_siginfo_t siginfo, *si; |
Namhyung Kim | 9fed81d | 2010-10-27 15:33:46 -0700 | [diff] [blame] | 1002 | void __user *datavp = (void __user *) data; |
| 1003 | unsigned long __user *datalp = datavp; |
Tejun Heo | fca26f2 | 2011-06-14 11:20:16 +0200 | [diff] [blame] | 1004 | unsigned long flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1005 | |
| 1006 | switch (request) { |
Roland McGrath | 16c3e38 | 2008-01-30 13:31:47 +0100 | [diff] [blame] | 1007 | case PTRACE_PEEKTEXT: |
| 1008 | case PTRACE_PEEKDATA: |
| 1009 | return generic_ptrace_peekdata(child, addr, data); |
| 1010 | case PTRACE_POKETEXT: |
| 1011 | case PTRACE_POKEDATA: |
| 1012 | return generic_ptrace_pokedata(child, addr, data); |
| 1013 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1014 | #ifdef PTRACE_OLDSETOPTIONS |
| 1015 | case PTRACE_OLDSETOPTIONS: |
| 1016 | #endif |
| 1017 | case PTRACE_SETOPTIONS: |
| 1018 | ret = ptrace_setoptions(child, data); |
| 1019 | break; |
| 1020 | case PTRACE_GETEVENTMSG: |
Namhyung Kim | 9fed81d | 2010-10-27 15:33:46 -0700 | [diff] [blame] | 1021 | ret = put_user(child->ptrace_message, datalp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1022 | break; |
Roland McGrath | e16b278 | 2008-04-20 13:10:12 -0700 | [diff] [blame] | 1023 | |
Andrey Vagin | 84c751b | 2013-04-30 15:27:59 -0700 | [diff] [blame] | 1024 | case PTRACE_PEEKSIGINFO: |
| 1025 | ret = ptrace_peek_siginfo(child, addr, data); |
| 1026 | break; |
| 1027 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1028 | case PTRACE_GETSIGINFO: |
Roland McGrath | e16b278 | 2008-04-20 13:10:12 -0700 | [diff] [blame] | 1029 | ret = ptrace_getsiginfo(child, &siginfo); |
| 1030 | if (!ret) |
Namhyung Kim | 9fed81d | 2010-10-27 15:33:46 -0700 | [diff] [blame] | 1031 | ret = copy_siginfo_to_user(datavp, &siginfo); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1032 | break; |
Roland McGrath | e16b278 | 2008-04-20 13:10:12 -0700 | [diff] [blame] | 1033 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1034 | case PTRACE_SETSIGINFO: |
Eric W. Biederman | 4cd2e0e | 2018-04-18 17:30:19 -0500 | [diff] [blame] | 1035 | ret = copy_siginfo_from_user(&siginfo, datavp); |
| 1036 | if (!ret) |
Roland McGrath | e16b278 | 2008-04-20 13:10:12 -0700 | [diff] [blame] | 1037 | ret = ptrace_setsiginfo(child, &siginfo); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1038 | break; |
Roland McGrath | e16b278 | 2008-04-20 13:10:12 -0700 | [diff] [blame] | 1039 | |
Andrei Vagin | fcfc2aa0 | 2019-03-28 20:44:13 -0700 | [diff] [blame] | 1040 | case PTRACE_GETSIGMASK: { |
| 1041 | sigset_t *mask; |
| 1042 | |
Andrey Vagin | 29000ca | 2013-07-03 15:08:12 -0700 | [diff] [blame] | 1043 | if (addr != sizeof(sigset_t)) { |
| 1044 | ret = -EINVAL; |
| 1045 | break; |
| 1046 | } |
| 1047 | |
Andrei Vagin | fcfc2aa0 | 2019-03-28 20:44:13 -0700 | [diff] [blame] | 1048 | if (test_tsk_restore_sigmask(child)) |
| 1049 | mask = &child->saved_sigmask; |
| 1050 | else |
| 1051 | mask = &child->blocked; |
| 1052 | |
| 1053 | if (copy_to_user(datavp, mask, sizeof(sigset_t))) |
Andrey Vagin | 29000ca | 2013-07-03 15:08:12 -0700 | [diff] [blame] | 1054 | ret = -EFAULT; |
| 1055 | else |
| 1056 | ret = 0; |
| 1057 | |
| 1058 | break; |
Andrei Vagin | fcfc2aa0 | 2019-03-28 20:44:13 -0700 | [diff] [blame] | 1059 | } |
Andrey Vagin | 29000ca | 2013-07-03 15:08:12 -0700 | [diff] [blame] | 1060 | |
| 1061 | case PTRACE_SETSIGMASK: { |
| 1062 | sigset_t new_set; |
| 1063 | |
| 1064 | if (addr != sizeof(sigset_t)) { |
| 1065 | ret = -EINVAL; |
| 1066 | break; |
| 1067 | } |
| 1068 | |
| 1069 | if (copy_from_user(&new_set, datavp, sizeof(sigset_t))) { |
| 1070 | ret = -EFAULT; |
| 1071 | break; |
| 1072 | } |
| 1073 | |
| 1074 | sigdelsetmask(&new_set, sigmask(SIGKILL)|sigmask(SIGSTOP)); |
| 1075 | |
| 1076 | /* |
| 1077 | * Every thread does recalc_sigpending() after resume, so |
| 1078 | * retarget_shared_pending() and recalc_sigpending() are not |
| 1079 | * called here. |
| 1080 | */ |
| 1081 | spin_lock_irq(&child->sighand->siglock); |
| 1082 | child->blocked = new_set; |
| 1083 | spin_unlock_irq(&child->sighand->siglock); |
| 1084 | |
Andrei Vagin | fcfc2aa0 | 2019-03-28 20:44:13 -0700 | [diff] [blame] | 1085 | clear_tsk_restore_sigmask(child); |
| 1086 | |
Andrey Vagin | 29000ca | 2013-07-03 15:08:12 -0700 | [diff] [blame] | 1087 | ret = 0; |
| 1088 | break; |
| 1089 | } |
| 1090 | |
Tejun Heo | fca26f2 | 2011-06-14 11:20:16 +0200 | [diff] [blame] | 1091 | case PTRACE_INTERRUPT: |
| 1092 | /* |
| 1093 | * Stop tracee without any side-effect on signal or job |
| 1094 | * control. At least one trap is guaranteed to happen |
| 1095 | * after this request. If @child is already trapped, the |
| 1096 | * current trap is not disturbed and another trap will |
| 1097 | * happen after the current trap is ended with PTRACE_CONT. |
| 1098 | * |
| 1099 | * The actual trap might not be PTRACE_EVENT_STOP trap but |
| 1100 | * the pending condition is cleared regardless. |
| 1101 | */ |
| 1102 | if (unlikely(!seized || !lock_task_sighand(child, &flags))) |
| 1103 | break; |
| 1104 | |
Tejun Heo | 544b2c9 | 2011-06-14 11:20:18 +0200 | [diff] [blame] | 1105 | /* |
| 1106 | * INTERRUPT doesn't disturb existing trap sans one |
| 1107 | * exception. If ptracer issued LISTEN for the current |
| 1108 | * STOP, this INTERRUPT should clear LISTEN and re-trap |
| 1109 | * tracee into STOP. |
| 1110 | */ |
Tejun Heo | fca26f2 | 2011-06-14 11:20:16 +0200 | [diff] [blame] | 1111 | if (likely(task_set_jobctl_pending(child, JOBCTL_TRAP_STOP))) |
Oleg Nesterov | 910ffdb1 | 2013-01-21 20:47:41 +0100 | [diff] [blame] | 1112 | ptrace_signal_wake_up(child, child->jobctl & JOBCTL_LISTENING); |
Tejun Heo | 544b2c9 | 2011-06-14 11:20:18 +0200 | [diff] [blame] | 1113 | |
| 1114 | unlock_task_sighand(child, &flags); |
| 1115 | ret = 0; |
| 1116 | break; |
| 1117 | |
| 1118 | case PTRACE_LISTEN: |
| 1119 | /* |
| 1120 | * Listen for events. Tracee must be in STOP. It's not |
| 1121 | * resumed per-se but is not considered to be in TRACED by |
| 1122 | * wait(2) or ptrace(2). If an async event (e.g. group |
| 1123 | * stop state change) happens, tracee will enter STOP trap |
| 1124 | * again. Alternatively, ptracer can issue INTERRUPT to |
| 1125 | * finish listening and re-trap tracee into STOP. |
| 1126 | */ |
| 1127 | if (unlikely(!seized || !lock_task_sighand(child, &flags))) |
| 1128 | break; |
| 1129 | |
| 1130 | si = child->last_siginfo; |
Oleg Nesterov | f9d81f6 | 2011-09-25 19:46:22 +0200 | [diff] [blame] | 1131 | if (likely(si && (si->si_code >> 8) == PTRACE_EVENT_STOP)) { |
| 1132 | child->jobctl |= JOBCTL_LISTENING; |
| 1133 | /* |
| 1134 | * If NOTIFY is set, it means event happened between |
| 1135 | * start of this trap and now. Trigger re-trap. |
| 1136 | */ |
| 1137 | if (child->jobctl & JOBCTL_TRAP_NOTIFY) |
Oleg Nesterov | 910ffdb1 | 2013-01-21 20:47:41 +0100 | [diff] [blame] | 1138 | ptrace_signal_wake_up(child, true); |
Oleg Nesterov | f9d81f6 | 2011-09-25 19:46:22 +0200 | [diff] [blame] | 1139 | ret = 0; |
| 1140 | } |
Tejun Heo | fca26f2 | 2011-06-14 11:20:16 +0200 | [diff] [blame] | 1141 | unlock_task_sighand(child, &flags); |
Tejun Heo | fca26f2 | 2011-06-14 11:20:16 +0200 | [diff] [blame] | 1142 | break; |
| 1143 | |
Alexey Dobriyan | 1bcf548 | 2007-10-16 01:23:45 -0700 | [diff] [blame] | 1144 | case PTRACE_DETACH: /* detach a process that was attached. */ |
| 1145 | ret = ptrace_detach(child, data); |
| 1146 | break; |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 1147 | |
Mike Frysinger | 9c1a125 | 2010-05-26 14:42:52 -0700 | [diff] [blame] | 1148 | #ifdef CONFIG_BINFMT_ELF_FDPIC |
| 1149 | case PTRACE_GETFDPIC: { |
Oleg Nesterov | e0129ef | 2010-05-26 14:42:53 -0700 | [diff] [blame] | 1150 | struct mm_struct *mm = get_task_mm(child); |
Mike Frysinger | 9c1a125 | 2010-05-26 14:42:52 -0700 | [diff] [blame] | 1151 | unsigned long tmp = 0; |
| 1152 | |
Oleg Nesterov | e0129ef | 2010-05-26 14:42:53 -0700 | [diff] [blame] | 1153 | ret = -ESRCH; |
| 1154 | if (!mm) |
| 1155 | break; |
| 1156 | |
Mike Frysinger | 9c1a125 | 2010-05-26 14:42:52 -0700 | [diff] [blame] | 1157 | switch (addr) { |
| 1158 | case PTRACE_GETFDPIC_EXEC: |
Oleg Nesterov | e0129ef | 2010-05-26 14:42:53 -0700 | [diff] [blame] | 1159 | tmp = mm->context.exec_fdpic_loadmap; |
Mike Frysinger | 9c1a125 | 2010-05-26 14:42:52 -0700 | [diff] [blame] | 1160 | break; |
| 1161 | case PTRACE_GETFDPIC_INTERP: |
Oleg Nesterov | e0129ef | 2010-05-26 14:42:53 -0700 | [diff] [blame] | 1162 | tmp = mm->context.interp_fdpic_loadmap; |
Mike Frysinger | 9c1a125 | 2010-05-26 14:42:52 -0700 | [diff] [blame] | 1163 | break; |
| 1164 | default: |
| 1165 | break; |
| 1166 | } |
Oleg Nesterov | e0129ef | 2010-05-26 14:42:53 -0700 | [diff] [blame] | 1167 | mmput(mm); |
Mike Frysinger | 9c1a125 | 2010-05-26 14:42:52 -0700 | [diff] [blame] | 1168 | |
Namhyung Kim | 9fed81d | 2010-10-27 15:33:46 -0700 | [diff] [blame] | 1169 | ret = put_user(tmp, datalp); |
Mike Frysinger | 9c1a125 | 2010-05-26 14:42:52 -0700 | [diff] [blame] | 1170 | break; |
| 1171 | } |
| 1172 | #endif |
| 1173 | |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 1174 | #ifdef PTRACE_SINGLESTEP |
| 1175 | case PTRACE_SINGLESTEP: |
| 1176 | #endif |
Roland McGrath | 5b88abb | 2008-01-30 13:30:53 +0100 | [diff] [blame] | 1177 | #ifdef PTRACE_SINGLEBLOCK |
| 1178 | case PTRACE_SINGLEBLOCK: |
| 1179 | #endif |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 1180 | #ifdef PTRACE_SYSEMU |
| 1181 | case PTRACE_SYSEMU: |
| 1182 | case PTRACE_SYSEMU_SINGLESTEP: |
| 1183 | #endif |
| 1184 | case PTRACE_SYSCALL: |
| 1185 | case PTRACE_CONT: |
| 1186 | return ptrace_resume(child, request, data); |
| 1187 | |
| 1188 | case PTRACE_KILL: |
| 1189 | if (child->exit_state) /* already dead */ |
| 1190 | return 0; |
| 1191 | return ptrace_resume(child, request, SIGKILL); |
| 1192 | |
Suresh Siddha | 2225a12 | 2010-02-11 11:51:00 -0800 | [diff] [blame] | 1193 | #ifdef CONFIG_HAVE_ARCH_TRACEHOOK |
| 1194 | case PTRACE_GETREGSET: |
Andrey Vagin | 29000ca | 2013-07-03 15:08:12 -0700 | [diff] [blame] | 1195 | case PTRACE_SETREGSET: { |
Suresh Siddha | 2225a12 | 2010-02-11 11:51:00 -0800 | [diff] [blame] | 1196 | struct iovec kiov; |
Namhyung Kim | 9fed81d | 2010-10-27 15:33:46 -0700 | [diff] [blame] | 1197 | struct iovec __user *uiov = datavp; |
Suresh Siddha | 2225a12 | 2010-02-11 11:51:00 -0800 | [diff] [blame] | 1198 | |
Linus Torvalds | 96d4f26 | 2019-01-03 18:57:57 -0800 | [diff] [blame] | 1199 | if (!access_ok(uiov, sizeof(*uiov))) |
Suresh Siddha | 2225a12 | 2010-02-11 11:51:00 -0800 | [diff] [blame] | 1200 | return -EFAULT; |
| 1201 | |
| 1202 | if (__get_user(kiov.iov_base, &uiov->iov_base) || |
| 1203 | __get_user(kiov.iov_len, &uiov->iov_len)) |
| 1204 | return -EFAULT; |
| 1205 | |
| 1206 | ret = ptrace_regset(child, request, addr, &kiov); |
| 1207 | if (!ret) |
| 1208 | ret = __put_user(kiov.iov_len, &uiov->iov_len); |
| 1209 | break; |
| 1210 | } |
Elvira Khabirova | 201766a | 2019-07-16 16:29:42 -0700 | [diff] [blame] | 1211 | |
| 1212 | case PTRACE_GET_SYSCALL_INFO: |
| 1213 | ret = ptrace_get_syscall_info(child, addr, datavp); |
| 1214 | break; |
Suresh Siddha | 2225a12 | 2010-02-11 11:51:00 -0800 | [diff] [blame] | 1215 | #endif |
Tycho Andersen | f8e529ed | 2015-10-27 09:23:59 +0900 | [diff] [blame] | 1216 | |
| 1217 | case PTRACE_SECCOMP_GET_FILTER: |
| 1218 | ret = seccomp_get_filter(child, addr, datavp); |
| 1219 | break; |
| 1220 | |
Tycho Andersen | 2650047 | 2017-10-11 09:39:21 -0600 | [diff] [blame] | 1221 | case PTRACE_SECCOMP_GET_METADATA: |
| 1222 | ret = seccomp_get_metadata(child, addr, datavp); |
| 1223 | break; |
| 1224 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1225 | default: |
| 1226 | break; |
| 1227 | } |
| 1228 | |
| 1229 | return ret; |
| 1230 | } |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 1231 | |
Christoph Hellwig | 0ac1555 | 2007-10-16 01:26:37 -0700 | [diff] [blame] | 1232 | #ifndef arch_ptrace_attach |
| 1233 | #define arch_ptrace_attach(child) do { } while (0) |
| 1234 | #endif |
| 1235 | |
Namhyung Kim | 4abf986 | 2010-10-27 15:33:45 -0700 | [diff] [blame] | 1236 | SYSCALL_DEFINE4(ptrace, long, request, long, pid, unsigned long, addr, |
| 1237 | unsigned long, data) |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 1238 | { |
| 1239 | struct task_struct *child; |
| 1240 | long ret; |
| 1241 | |
Christoph Hellwig | 6b9c7ed8 | 2006-01-08 01:02:33 -0800 | [diff] [blame] | 1242 | if (request == PTRACE_TRACEME) { |
| 1243 | ret = ptrace_traceme(); |
Haavard Skinnemoen | 6ea6dd9 | 2007-11-27 13:02:40 +0100 | [diff] [blame] | 1244 | if (!ret) |
| 1245 | arch_ptrace_attach(current); |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 1246 | goto out; |
Christoph Hellwig | 6b9c7ed8 | 2006-01-08 01:02:33 -0800 | [diff] [blame] | 1247 | } |
| 1248 | |
Mike Rapoport | 2ee0826 | 2018-02-06 15:40:17 -0800 | [diff] [blame] | 1249 | child = find_get_task_by_vpid(pid); |
| 1250 | if (!child) { |
| 1251 | ret = -ESRCH; |
Christoph Hellwig | 6b9c7ed8 | 2006-01-08 01:02:33 -0800 | [diff] [blame] | 1252 | goto out; |
| 1253 | } |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 1254 | |
Tejun Heo | 3544d72 | 2011-06-14 11:20:15 +0200 | [diff] [blame] | 1255 | if (request == PTRACE_ATTACH || request == PTRACE_SEIZE) { |
Denys Vlasenko | aa9147c | 2012-03-23 15:02:42 -0700 | [diff] [blame] | 1256 | ret = ptrace_attach(child, request, addr, data); |
Christoph Hellwig | 0ac1555 | 2007-10-16 01:26:37 -0700 | [diff] [blame] | 1257 | /* |
| 1258 | * Some architectures need to do book-keeping after |
| 1259 | * a ptrace attach. |
| 1260 | */ |
| 1261 | if (!ret) |
| 1262 | arch_ptrace_attach(child); |
Christoph Hellwig | 005f18d | 2005-11-13 16:06:33 -0800 | [diff] [blame] | 1263 | goto out_put_task_struct; |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 1264 | } |
| 1265 | |
Tejun Heo | fca26f2 | 2011-06-14 11:20:16 +0200 | [diff] [blame] | 1266 | ret = ptrace_check_attach(child, request == PTRACE_KILL || |
| 1267 | request == PTRACE_INTERRUPT); |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 1268 | if (ret < 0) |
| 1269 | goto out_put_task_struct; |
| 1270 | |
| 1271 | ret = arch_ptrace(child, request, addr, data); |
Oleg Nesterov | 9899d11 | 2013-01-21 20:48:00 +0100 | [diff] [blame] | 1272 | if (ret || request != PTRACE_DETACH) |
| 1273 | ptrace_unfreeze_traced(child); |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 1274 | |
| 1275 | out_put_task_struct: |
| 1276 | put_task_struct(child); |
| 1277 | out: |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 1278 | return ret; |
| 1279 | } |
Alexey Dobriyan | 7664732 | 2007-07-17 04:03:43 -0700 | [diff] [blame] | 1280 | |
Namhyung Kim | 4abf986 | 2010-10-27 15:33:45 -0700 | [diff] [blame] | 1281 | int generic_ptrace_peekdata(struct task_struct *tsk, unsigned long addr, |
| 1282 | unsigned long data) |
Alexey Dobriyan | 7664732 | 2007-07-17 04:03:43 -0700 | [diff] [blame] | 1283 | { |
| 1284 | unsigned long tmp; |
| 1285 | int copied; |
| 1286 | |
Eric W. Biederman | 84d77d3 | 2016-11-22 12:06:50 -0600 | [diff] [blame] | 1287 | copied = ptrace_access_vm(tsk, addr, &tmp, sizeof(tmp), FOLL_FORCE); |
Alexey Dobriyan | 7664732 | 2007-07-17 04:03:43 -0700 | [diff] [blame] | 1288 | if (copied != sizeof(tmp)) |
| 1289 | return -EIO; |
| 1290 | return put_user(tmp, (unsigned long __user *)data); |
| 1291 | } |
Alexey Dobriyan | f284ce7 | 2007-07-17 04:03:44 -0700 | [diff] [blame] | 1292 | |
Namhyung Kim | 4abf986 | 2010-10-27 15:33:45 -0700 | [diff] [blame] | 1293 | int generic_ptrace_pokedata(struct task_struct *tsk, unsigned long addr, |
| 1294 | unsigned long data) |
Alexey Dobriyan | f284ce7 | 2007-07-17 04:03:44 -0700 | [diff] [blame] | 1295 | { |
| 1296 | int copied; |
| 1297 | |
Eric W. Biederman | 84d77d3 | 2016-11-22 12:06:50 -0600 | [diff] [blame] | 1298 | copied = ptrace_access_vm(tsk, addr, &data, sizeof(data), |
Lorenzo Stoakes | f307ab6 | 2016-10-13 01:20:20 +0100 | [diff] [blame] | 1299 | FOLL_FORCE | FOLL_WRITE); |
Alexey Dobriyan | f284ce7 | 2007-07-17 04:03:44 -0700 | [diff] [blame] | 1300 | return (copied == sizeof(data)) ? 0 : -EIO; |
| 1301 | } |
Roland McGrath | 032d82d | 2008-01-30 13:31:47 +0100 | [diff] [blame] | 1302 | |
Christoph Hellwig | 96b8936 | 2008-11-25 08:10:03 +0100 | [diff] [blame] | 1303 | #if defined CONFIG_COMPAT |
Roland McGrath | 032d82d | 2008-01-30 13:31:47 +0100 | [diff] [blame] | 1304 | |
| 1305 | int compat_ptrace_request(struct task_struct *child, compat_long_t request, |
| 1306 | compat_ulong_t addr, compat_ulong_t data) |
| 1307 | { |
| 1308 | compat_ulong_t __user *datap = compat_ptr(data); |
| 1309 | compat_ulong_t word; |
Eric W. Biederman | ae7795b | 2018-09-25 11:27:20 +0200 | [diff] [blame] | 1310 | kernel_siginfo_t siginfo; |
Roland McGrath | 032d82d | 2008-01-30 13:31:47 +0100 | [diff] [blame] | 1311 | int ret; |
| 1312 | |
| 1313 | switch (request) { |
| 1314 | case PTRACE_PEEKTEXT: |
| 1315 | case PTRACE_PEEKDATA: |
Eric W. Biederman | 84d77d3 | 2016-11-22 12:06:50 -0600 | [diff] [blame] | 1316 | ret = ptrace_access_vm(child, addr, &word, sizeof(word), |
Lorenzo Stoakes | f307ab6 | 2016-10-13 01:20:20 +0100 | [diff] [blame] | 1317 | FOLL_FORCE); |
Roland McGrath | 032d82d | 2008-01-30 13:31:47 +0100 | [diff] [blame] | 1318 | if (ret != sizeof(word)) |
| 1319 | ret = -EIO; |
| 1320 | else |
| 1321 | ret = put_user(word, datap); |
| 1322 | break; |
| 1323 | |
| 1324 | case PTRACE_POKETEXT: |
| 1325 | case PTRACE_POKEDATA: |
Eric W. Biederman | 84d77d3 | 2016-11-22 12:06:50 -0600 | [diff] [blame] | 1326 | ret = ptrace_access_vm(child, addr, &data, sizeof(data), |
Lorenzo Stoakes | f307ab6 | 2016-10-13 01:20:20 +0100 | [diff] [blame] | 1327 | FOLL_FORCE | FOLL_WRITE); |
Roland McGrath | 032d82d | 2008-01-30 13:31:47 +0100 | [diff] [blame] | 1328 | ret = (ret != sizeof(data) ? -EIO : 0); |
| 1329 | break; |
| 1330 | |
| 1331 | case PTRACE_GETEVENTMSG: |
| 1332 | ret = put_user((compat_ulong_t) child->ptrace_message, datap); |
| 1333 | break; |
| 1334 | |
Roland McGrath | e16b278 | 2008-04-20 13:10:12 -0700 | [diff] [blame] | 1335 | case PTRACE_GETSIGINFO: |
| 1336 | ret = ptrace_getsiginfo(child, &siginfo); |
| 1337 | if (!ret) |
| 1338 | ret = copy_siginfo_to_user32( |
| 1339 | (struct compat_siginfo __user *) datap, |
| 1340 | &siginfo); |
| 1341 | break; |
| 1342 | |
| 1343 | case PTRACE_SETSIGINFO: |
Eric W. Biederman | 4cd2e0e | 2018-04-18 17:30:19 -0500 | [diff] [blame] | 1344 | ret = copy_siginfo_from_user32( |
| 1345 | &siginfo, (struct compat_siginfo __user *) datap); |
| 1346 | if (!ret) |
Roland McGrath | e16b278 | 2008-04-20 13:10:12 -0700 | [diff] [blame] | 1347 | ret = ptrace_setsiginfo(child, &siginfo); |
| 1348 | break; |
Suresh Siddha | 2225a12 | 2010-02-11 11:51:00 -0800 | [diff] [blame] | 1349 | #ifdef CONFIG_HAVE_ARCH_TRACEHOOK |
| 1350 | case PTRACE_GETREGSET: |
| 1351 | case PTRACE_SETREGSET: |
| 1352 | { |
| 1353 | struct iovec kiov; |
| 1354 | struct compat_iovec __user *uiov = |
| 1355 | (struct compat_iovec __user *) datap; |
| 1356 | compat_uptr_t ptr; |
| 1357 | compat_size_t len; |
| 1358 | |
Linus Torvalds | 96d4f26 | 2019-01-03 18:57:57 -0800 | [diff] [blame] | 1359 | if (!access_ok(uiov, sizeof(*uiov))) |
Suresh Siddha | 2225a12 | 2010-02-11 11:51:00 -0800 | [diff] [blame] | 1360 | return -EFAULT; |
| 1361 | |
| 1362 | if (__get_user(ptr, &uiov->iov_base) || |
| 1363 | __get_user(len, &uiov->iov_len)) |
| 1364 | return -EFAULT; |
| 1365 | |
| 1366 | kiov.iov_base = compat_ptr(ptr); |
| 1367 | kiov.iov_len = len; |
| 1368 | |
| 1369 | ret = ptrace_regset(child, request, addr, &kiov); |
| 1370 | if (!ret) |
| 1371 | ret = __put_user(kiov.iov_len, &uiov->iov_len); |
| 1372 | break; |
| 1373 | } |
| 1374 | #endif |
Roland McGrath | e16b278 | 2008-04-20 13:10:12 -0700 | [diff] [blame] | 1375 | |
Roland McGrath | 032d82d | 2008-01-30 13:31:47 +0100 | [diff] [blame] | 1376 | default: |
| 1377 | ret = ptrace_request(child, request, addr, data); |
| 1378 | } |
| 1379 | |
| 1380 | return ret; |
| 1381 | } |
Roland McGrath | c269f19 | 2008-01-30 13:31:48 +0100 | [diff] [blame] | 1382 | |
Heiko Carstens | 62a6fa97 | 2014-03-03 16:11:13 +0100 | [diff] [blame] | 1383 | COMPAT_SYSCALL_DEFINE4(ptrace, compat_long_t, request, compat_long_t, pid, |
| 1384 | compat_long_t, addr, compat_long_t, data) |
Roland McGrath | c269f19 | 2008-01-30 13:31:48 +0100 | [diff] [blame] | 1385 | { |
| 1386 | struct task_struct *child; |
| 1387 | long ret; |
| 1388 | |
Roland McGrath | c269f19 | 2008-01-30 13:31:48 +0100 | [diff] [blame] | 1389 | if (request == PTRACE_TRACEME) { |
| 1390 | ret = ptrace_traceme(); |
| 1391 | goto out; |
| 1392 | } |
| 1393 | |
Mike Rapoport | 2ee0826 | 2018-02-06 15:40:17 -0800 | [diff] [blame] | 1394 | child = find_get_task_by_vpid(pid); |
| 1395 | if (!child) { |
| 1396 | ret = -ESRCH; |
Roland McGrath | c269f19 | 2008-01-30 13:31:48 +0100 | [diff] [blame] | 1397 | goto out; |
| 1398 | } |
| 1399 | |
Tejun Heo | 3544d72 | 2011-06-14 11:20:15 +0200 | [diff] [blame] | 1400 | if (request == PTRACE_ATTACH || request == PTRACE_SEIZE) { |
Denys Vlasenko | aa9147c | 2012-03-23 15:02:42 -0700 | [diff] [blame] | 1401 | ret = ptrace_attach(child, request, addr, data); |
Roland McGrath | c269f19 | 2008-01-30 13:31:48 +0100 | [diff] [blame] | 1402 | /* |
| 1403 | * Some architectures need to do book-keeping after |
| 1404 | * a ptrace attach. |
| 1405 | */ |
| 1406 | if (!ret) |
| 1407 | arch_ptrace_attach(child); |
| 1408 | goto out_put_task_struct; |
| 1409 | } |
| 1410 | |
Tejun Heo | fca26f2 | 2011-06-14 11:20:16 +0200 | [diff] [blame] | 1411 | ret = ptrace_check_attach(child, request == PTRACE_KILL || |
| 1412 | request == PTRACE_INTERRUPT); |
Oleg Nesterov | 9899d11 | 2013-01-21 20:48:00 +0100 | [diff] [blame] | 1413 | if (!ret) { |
Roland McGrath | c269f19 | 2008-01-30 13:31:48 +0100 | [diff] [blame] | 1414 | ret = compat_arch_ptrace(child, request, addr, data); |
Oleg Nesterov | 9899d11 | 2013-01-21 20:48:00 +0100 | [diff] [blame] | 1415 | if (ret || request != PTRACE_DETACH) |
| 1416 | ptrace_unfreeze_traced(child); |
| 1417 | } |
Roland McGrath | c269f19 | 2008-01-30 13:31:48 +0100 | [diff] [blame] | 1418 | |
| 1419 | out_put_task_struct: |
| 1420 | put_task_struct(child); |
| 1421 | out: |
Roland McGrath | c269f19 | 2008-01-30 13:31:48 +0100 | [diff] [blame] | 1422 | return ret; |
| 1423 | } |
Christoph Hellwig | 96b8936 | 2008-11-25 08:10:03 +0100 | [diff] [blame] | 1424 | #endif /* CONFIG_COMPAT */ |