Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
Randy.Dunlap | c59ede7 | 2006-01-11 12:17:46 -0800 | [diff] [blame] | 10 | #include <linux/capability.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | #include <linux/module.h> |
| 12 | #include <linux/sched.h> |
| 13 | #include <linux/errno.h> |
| 14 | #include <linux/mm.h> |
| 15 | #include <linux/highmem.h> |
| 16 | #include <linux/pagemap.h> |
| 17 | #include <linux/smp_lock.h> |
| 18 | #include <linux/ptrace.h> |
| 19 | #include <linux/security.h> |
Jesper Juhl | 7ed20e1 | 2005-05-01 08:59:14 -0700 | [diff] [blame] | 20 | #include <linux/signal.h> |
Al Viro | a5cb013 | 2007-03-20 13:58:35 -0400 | [diff] [blame] | 21 | #include <linux/audit.h> |
Pavel Emelyanov | b488893 | 2007-10-18 23:40:14 -0700 | [diff] [blame] | 22 | #include <linux/pid_namespace.h> |
Adrian Bunk | f17d30a | 2008-02-06 01:36:44 -0800 | [diff] [blame] | 23 | #include <linux/syscalls.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | |
| 25 | #include <asm/pgtable.h> |
| 26 | #include <asm/uaccess.h> |
| 27 | |
Markus Metzger | bf53de9 | 2008-12-19 15:10:24 +0100 | [diff] [blame] | 28 | |
| 29 | /* |
| 30 | * Initialize a new task whose father had been ptraced. |
| 31 | * |
| 32 | * Called from copy_process(). |
| 33 | */ |
| 34 | void ptrace_fork(struct task_struct *child, unsigned long clone_flags) |
| 35 | { |
| 36 | arch_ptrace_fork(child, clone_flags); |
| 37 | } |
| 38 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 39 | /* |
| 40 | * ptrace a task: make the debugger its new parent and |
| 41 | * move it to the ptrace list. |
| 42 | * |
| 43 | * Must be called with the tasklist lock write-held. |
| 44 | */ |
Ingo Molnar | 36c8b58 | 2006-07-03 00:25:41 -0700 | [diff] [blame] | 45 | void __ptrace_link(struct task_struct *child, struct task_struct *new_parent) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 46 | { |
Roland McGrath | f470021 | 2008-03-24 18:36:23 -0700 | [diff] [blame] | 47 | BUG_ON(!list_empty(&child->ptrace_entry)); |
| 48 | list_add(&child->ptrace_entry, &new_parent->ptraced); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 49 | child->parent = new_parent; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | } |
| 51 | |
| 52 | /* |
| 53 | * Turn a tracing stop into a normal stop now, since with no tracer there |
| 54 | * would be no way to wake it up with SIGCONT or SIGKILL. If there was a |
| 55 | * signal sent that would resume the child, but didn't because it was in |
| 56 | * TASK_TRACED, resume it now. |
| 57 | * Requires that irqs be disabled. |
| 58 | */ |
Adrian Bunk | b747c8c | 2008-10-18 20:28:21 -0700 | [diff] [blame] | 59 | static void ptrace_untrace(struct task_struct *child) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 60 | { |
| 61 | spin_lock(&child->sighand->siglock); |
Matthew Wilcox | 6618a3e | 2007-12-06 11:06:16 -0500 | [diff] [blame] | 62 | if (task_is_traced(child)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 63 | if (child->signal->flags & SIGNAL_STOP_STOPPED) { |
Oleg Nesterov | d9ae90a | 2008-02-06 01:36:13 -0800 | [diff] [blame] | 64 | __set_task_state(child, TASK_STOPPED); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 65 | } else { |
| 66 | signal_wake_up(child, 1); |
| 67 | } |
| 68 | } |
| 69 | spin_unlock(&child->sighand->siglock); |
| 70 | } |
| 71 | |
| 72 | /* |
| 73 | * unptrace a task: move it back to its original parent and |
| 74 | * remove it from the ptrace list. |
| 75 | * |
| 76 | * Must be called with the tasklist lock write-held. |
| 77 | */ |
Ingo Molnar | 36c8b58 | 2006-07-03 00:25:41 -0700 | [diff] [blame] | 78 | void __ptrace_unlink(struct task_struct *child) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 79 | { |
Oleg Nesterov | 5ecfbae | 2006-02-15 22:50:10 +0300 | [diff] [blame] | 80 | BUG_ON(!child->ptrace); |
| 81 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 82 | child->ptrace = 0; |
Roland McGrath | f470021 | 2008-03-24 18:36:23 -0700 | [diff] [blame] | 83 | child->parent = child->real_parent; |
| 84 | list_del_init(&child->ptrace_entry); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 85 | |
Markus Metzger | bf53de9 | 2008-12-19 15:10:24 +0100 | [diff] [blame] | 86 | arch_ptrace_untrace(child); |
Matthew Wilcox | 6618a3e | 2007-12-06 11:06:16 -0500 | [diff] [blame] | 87 | if (task_is_traced(child)) |
Roland McGrath | e57a505 | 2006-04-12 16:30:20 -0700 | [diff] [blame] | 88 | ptrace_untrace(child); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 89 | } |
| 90 | |
| 91 | /* |
| 92 | * Check that we have indeed attached to the thing.. |
| 93 | */ |
| 94 | int ptrace_check_attach(struct task_struct *child, int kill) |
| 95 | { |
| 96 | int ret = -ESRCH; |
| 97 | |
| 98 | /* |
| 99 | * We take the read lock around doing both checks to close a |
| 100 | * possible race where someone else was tracing our child and |
| 101 | * detached between these two checks. After this locked check, |
| 102 | * we are sure that this is our traced child and that can only |
| 103 | * be changed by us so it's not changing right after this. |
| 104 | */ |
| 105 | read_lock(&tasklist_lock); |
Oleg Nesterov | c0c0b64 | 2008-02-08 04:19:00 -0800 | [diff] [blame] | 106 | if ((child->ptrace & PT_PTRACED) && child->parent == current) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | ret = 0; |
Oleg Nesterov | c0c0b64 | 2008-02-08 04:19:00 -0800 | [diff] [blame] | 108 | /* |
| 109 | * child->sighand can't be NULL, release_task() |
| 110 | * does ptrace_unlink() before __exit_signal(). |
| 111 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | spin_lock_irq(&child->sighand->siglock); |
Oleg Nesterov | d9ae90a | 2008-02-06 01:36:13 -0800 | [diff] [blame] | 113 | if (task_is_stopped(child)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 114 | child->state = TASK_TRACED; |
Oleg Nesterov | d9ae90a | 2008-02-06 01:36:13 -0800 | [diff] [blame] | 115 | else if (!task_is_traced(child) && !kill) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 116 | ret = -ESRCH; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 117 | spin_unlock_irq(&child->sighand->siglock); |
| 118 | } |
| 119 | read_unlock(&tasklist_lock); |
| 120 | |
Oleg Nesterov | d9ae90a | 2008-02-06 01:36:13 -0800 | [diff] [blame] | 121 | if (!ret && !kill) |
Roland McGrath | 85ba2d8 | 2008-07-25 19:45:58 -0700 | [diff] [blame] | 122 | ret = wait_task_inactive(child, TASK_TRACED) ? 0 : -ESRCH; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 123 | |
| 124 | /* All systems go.. */ |
| 125 | return ret; |
| 126 | } |
| 127 | |
Stephen Smalley | 006ebb4 | 2008-05-19 08:32:49 -0400 | [diff] [blame] | 128 | int __ptrace_may_access(struct task_struct *task, unsigned int mode) |
Miklos Szeredi | ab8d11b | 2005-09-06 15:18:24 -0700 | [diff] [blame] | 129 | { |
David Howells | c69e8d9 | 2008-11-14 10:39:19 +1100 | [diff] [blame] | 130 | const struct cred *cred = current_cred(), *tcred; |
David Howells | b6dff3e | 2008-11-14 10:39:16 +1100 | [diff] [blame] | 131 | |
Eric W. Biederman | df26c40 | 2006-06-26 00:25:59 -0700 | [diff] [blame] | 132 | /* May we inspect the given task? |
| 133 | * This check is used both for attaching with ptrace |
| 134 | * and for allowing access to sensitive information in /proc. |
| 135 | * |
| 136 | * ptrace_attach denies several cases that /proc allows |
| 137 | * because setting up the necessary parent/child relationship |
| 138 | * or halting the specified task is impossible. |
| 139 | */ |
| 140 | int dumpable = 0; |
| 141 | /* Don't let security modules deny introspection */ |
| 142 | if (task == current) |
| 143 | return 0; |
David Howells | c69e8d9 | 2008-11-14 10:39:19 +1100 | [diff] [blame] | 144 | rcu_read_lock(); |
| 145 | tcred = __task_cred(task); |
| 146 | if ((cred->uid != tcred->euid || |
| 147 | cred->uid != tcred->suid || |
| 148 | cred->uid != tcred->uid || |
| 149 | cred->gid != tcred->egid || |
| 150 | cred->gid != tcred->sgid || |
| 151 | cred->gid != tcred->gid) && |
| 152 | !capable(CAP_SYS_PTRACE)) { |
| 153 | rcu_read_unlock(); |
Miklos Szeredi | ab8d11b | 2005-09-06 15:18:24 -0700 | [diff] [blame] | 154 | return -EPERM; |
David Howells | c69e8d9 | 2008-11-14 10:39:19 +1100 | [diff] [blame] | 155 | } |
| 156 | rcu_read_unlock(); |
Miklos Szeredi | ab8d11b | 2005-09-06 15:18:24 -0700 | [diff] [blame] | 157 | smp_rmb(); |
Eric W. Biederman | df26c40 | 2006-06-26 00:25:59 -0700 | [diff] [blame] | 158 | if (task->mm) |
Kawai, Hidehiro | 6c5d523 | 2007-07-19 01:48:27 -0700 | [diff] [blame] | 159 | dumpable = get_dumpable(task->mm); |
Eric W. Biederman | df26c40 | 2006-06-26 00:25:59 -0700 | [diff] [blame] | 160 | if (!dumpable && !capable(CAP_SYS_PTRACE)) |
Miklos Szeredi | ab8d11b | 2005-09-06 15:18:24 -0700 | [diff] [blame] | 161 | return -EPERM; |
| 162 | |
David Howells | 5cd9c58 | 2008-08-14 11:37:28 +0100 | [diff] [blame] | 163 | return security_ptrace_may_access(task, mode); |
Miklos Szeredi | ab8d11b | 2005-09-06 15:18:24 -0700 | [diff] [blame] | 164 | } |
| 165 | |
Stephen Smalley | 006ebb4 | 2008-05-19 08:32:49 -0400 | [diff] [blame] | 166 | bool ptrace_may_access(struct task_struct *task, unsigned int mode) |
Miklos Szeredi | ab8d11b | 2005-09-06 15:18:24 -0700 | [diff] [blame] | 167 | { |
| 168 | int err; |
| 169 | task_lock(task); |
Stephen Smalley | 006ebb4 | 2008-05-19 08:32:49 -0400 | [diff] [blame] | 170 | err = __ptrace_may_access(task, mode); |
Miklos Szeredi | ab8d11b | 2005-09-06 15:18:24 -0700 | [diff] [blame] | 171 | task_unlock(task); |
Stephen Smalley | 006ebb4 | 2008-05-19 08:32:49 -0400 | [diff] [blame] | 172 | return (!err ? true : false); |
Miklos Szeredi | ab8d11b | 2005-09-06 15:18:24 -0700 | [diff] [blame] | 173 | } |
| 174 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 175 | int ptrace_attach(struct task_struct *task) |
| 176 | { |
| 177 | int retval; |
Sripathi Kodi | 6175ecf | 2007-07-15 23:39:26 -0700 | [diff] [blame] | 178 | unsigned long flags; |
Linus Torvalds | f5b40e3 | 2006-05-07 10:49:33 -0700 | [diff] [blame] | 179 | |
Al Viro | a5cb013 | 2007-03-20 13:58:35 -0400 | [diff] [blame] | 180 | audit_ptrace(task); |
| 181 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 182 | retval = -EPERM; |
Pavel Emelyanov | bac0abd | 2007-10-18 23:40:18 -0700 | [diff] [blame] | 183 | if (same_thread_group(task, current)) |
Linus Torvalds | f5b40e3 | 2006-05-07 10:49:33 -0700 | [diff] [blame] | 184 | goto out; |
| 185 | |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 186 | /* Protect exec's credential calculations against our interference; |
| 187 | * SUID, SGID and LSM creds get determined differently under ptrace. |
| 188 | */ |
| 189 | retval = mutex_lock_interruptible(¤t->cred_exec_mutex); |
| 190 | if (retval < 0) |
| 191 | goto out; |
| 192 | |
| 193 | retval = -EPERM; |
Linus Torvalds | f358166 | 2006-05-11 11:08:49 -0700 | [diff] [blame] | 194 | repeat: |
| 195 | /* |
| 196 | * Nasty, nasty. |
| 197 | * |
| 198 | * We want to hold both the task-lock and the |
| 199 | * tasklist_lock for writing at the same time. |
| 200 | * But that's against the rules (tasklist_lock |
| 201 | * is taken for reading by interrupts on other |
| 202 | * cpu's that may have task_lock). |
| 203 | */ |
Linus Torvalds | f5b40e3 | 2006-05-07 10:49:33 -0700 | [diff] [blame] | 204 | task_lock(task); |
Sripathi Kodi | 6175ecf | 2007-07-15 23:39:26 -0700 | [diff] [blame] | 205 | if (!write_trylock_irqsave(&tasklist_lock, flags)) { |
Linus Torvalds | f358166 | 2006-05-11 11:08:49 -0700 | [diff] [blame] | 206 | task_unlock(task); |
| 207 | do { |
| 208 | cpu_relax(); |
| 209 | } while (!write_can_lock(&tasklist_lock)); |
| 210 | goto repeat; |
| 211 | } |
Linus Torvalds | f5b40e3 | 2006-05-07 10:49:33 -0700 | [diff] [blame] | 212 | |
Eric W. Biederman | df26c40 | 2006-06-26 00:25:59 -0700 | [diff] [blame] | 213 | if (!task->mm) |
| 214 | goto bad; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 215 | /* the same process cannot be attached many times */ |
| 216 | if (task->ptrace & PT_PTRACED) |
| 217 | goto bad; |
Stephen Smalley | 006ebb4 | 2008-05-19 08:32:49 -0400 | [diff] [blame] | 218 | retval = __ptrace_may_access(task, PTRACE_MODE_ATTACH); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 219 | if (retval) |
| 220 | goto bad; |
| 221 | |
| 222 | /* Go */ |
Oleg Nesterov | 6b39c7b | 2008-02-08 04:18:58 -0800 | [diff] [blame] | 223 | task->ptrace |= PT_PTRACED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 224 | if (capable(CAP_SYS_PTRACE)) |
| 225 | task->ptrace |= PT_PTRACE_CAP; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 226 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 227 | __ptrace_link(task, current); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 228 | |
Oleg Nesterov | 33e9fc7 | 2008-04-30 00:53:14 -0700 | [diff] [blame] | 229 | send_sig_info(SIGSTOP, SEND_SIG_FORCED, task); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 230 | bad: |
Sripathi Kodi | 6175ecf | 2007-07-15 23:39:26 -0700 | [diff] [blame] | 231 | write_unlock_irqrestore(&tasklist_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 232 | task_unlock(task); |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 233 | mutex_unlock(¤t->cred_exec_mutex); |
Linus Torvalds | f5b40e3 | 2006-05-07 10:49:33 -0700 | [diff] [blame] | 234 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 235 | return retval; |
| 236 | } |
| 237 | |
Oleg Nesterov | d5f70c0 | 2006-06-26 00:26:07 -0700 | [diff] [blame] | 238 | static inline void __ptrace_detach(struct task_struct *child, unsigned int data) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 239 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 240 | child->exit_code = data; |
Oleg Nesterov | 5ecfbae | 2006-02-15 22:50:10 +0300 | [diff] [blame] | 241 | /* .. re-parent .. */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 242 | __ptrace_unlink(child); |
| 243 | /* .. and wake it up. */ |
| 244 | if (child->exit_state != EXIT_ZOMBIE) |
| 245 | wake_up_process(child); |
Oleg Nesterov | 5ecfbae | 2006-02-15 22:50:10 +0300 | [diff] [blame] | 246 | } |
| 247 | |
| 248 | int ptrace_detach(struct task_struct *child, unsigned int data) |
| 249 | { |
| 250 | if (!valid_signal(data)) |
| 251 | return -EIO; |
| 252 | |
| 253 | /* Architecture-specific hardware disable .. */ |
| 254 | ptrace_disable(child); |
Roland McGrath | 7d94143 | 2007-09-05 03:05:56 -0700 | [diff] [blame] | 255 | clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
Oleg Nesterov | 5ecfbae | 2006-02-15 22:50:10 +0300 | [diff] [blame] | 256 | |
| 257 | write_lock_irq(&tasklist_lock); |
Oleg Nesterov | d5f70c0 | 2006-06-26 00:26:07 -0700 | [diff] [blame] | 258 | /* protect against de_thread()->release_task() */ |
Oleg Nesterov | 5ecfbae | 2006-02-15 22:50:10 +0300 | [diff] [blame] | 259 | if (child->ptrace) |
| 260 | __ptrace_detach(child, data); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 261 | write_unlock_irq(&tasklist_lock); |
| 262 | |
| 263 | return 0; |
| 264 | } |
| 265 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 266 | int ptrace_readdata(struct task_struct *tsk, unsigned long src, char __user *dst, int len) |
| 267 | { |
| 268 | int copied = 0; |
| 269 | |
| 270 | while (len > 0) { |
| 271 | char buf[128]; |
| 272 | int this_len, retval; |
| 273 | |
| 274 | this_len = (len > sizeof(buf)) ? sizeof(buf) : len; |
| 275 | retval = access_process_vm(tsk, src, buf, this_len, 0); |
| 276 | if (!retval) { |
| 277 | if (copied) |
| 278 | break; |
| 279 | return -EIO; |
| 280 | } |
| 281 | if (copy_to_user(dst, buf, retval)) |
| 282 | return -EFAULT; |
| 283 | copied += retval; |
| 284 | src += retval; |
| 285 | dst += retval; |
| 286 | len -= retval; |
| 287 | } |
| 288 | return copied; |
| 289 | } |
| 290 | |
| 291 | int ptrace_writedata(struct task_struct *tsk, char __user *src, unsigned long dst, int len) |
| 292 | { |
| 293 | int copied = 0; |
| 294 | |
| 295 | while (len > 0) { |
| 296 | char buf[128]; |
| 297 | int this_len, retval; |
| 298 | |
| 299 | this_len = (len > sizeof(buf)) ? sizeof(buf) : len; |
| 300 | if (copy_from_user(buf, src, this_len)) |
| 301 | return -EFAULT; |
| 302 | retval = access_process_vm(tsk, dst, buf, this_len, 1); |
| 303 | if (!retval) { |
| 304 | if (copied) |
| 305 | break; |
| 306 | return -EIO; |
| 307 | } |
| 308 | copied += retval; |
| 309 | src += retval; |
| 310 | dst += retval; |
| 311 | len -= retval; |
| 312 | } |
| 313 | return copied; |
| 314 | } |
| 315 | |
| 316 | static int ptrace_setoptions(struct task_struct *child, long data) |
| 317 | { |
| 318 | child->ptrace &= ~PT_TRACE_MASK; |
| 319 | |
| 320 | if (data & PTRACE_O_TRACESYSGOOD) |
| 321 | child->ptrace |= PT_TRACESYSGOOD; |
| 322 | |
| 323 | if (data & PTRACE_O_TRACEFORK) |
| 324 | child->ptrace |= PT_TRACE_FORK; |
| 325 | |
| 326 | if (data & PTRACE_O_TRACEVFORK) |
| 327 | child->ptrace |= PT_TRACE_VFORK; |
| 328 | |
| 329 | if (data & PTRACE_O_TRACECLONE) |
| 330 | child->ptrace |= PT_TRACE_CLONE; |
| 331 | |
| 332 | if (data & PTRACE_O_TRACEEXEC) |
| 333 | child->ptrace |= PT_TRACE_EXEC; |
| 334 | |
| 335 | if (data & PTRACE_O_TRACEVFORKDONE) |
| 336 | child->ptrace |= PT_TRACE_VFORK_DONE; |
| 337 | |
| 338 | if (data & PTRACE_O_TRACEEXIT) |
| 339 | child->ptrace |= PT_TRACE_EXIT; |
| 340 | |
| 341 | return (data & ~PTRACE_O_MASK) ? -EINVAL : 0; |
| 342 | } |
| 343 | |
Roland McGrath | e16b278 | 2008-04-20 13:10:12 -0700 | [diff] [blame] | 344 | static int ptrace_getsiginfo(struct task_struct *child, siginfo_t *info) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 345 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 346 | int error = -ESRCH; |
| 347 | |
| 348 | read_lock(&tasklist_lock); |
| 349 | if (likely(child->sighand != NULL)) { |
| 350 | error = -EINVAL; |
| 351 | spin_lock_irq(&child->sighand->siglock); |
| 352 | if (likely(child->last_siginfo != NULL)) { |
Roland McGrath | e16b278 | 2008-04-20 13:10:12 -0700 | [diff] [blame] | 353 | *info = *child->last_siginfo; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 354 | error = 0; |
| 355 | } |
| 356 | spin_unlock_irq(&child->sighand->siglock); |
| 357 | } |
| 358 | read_unlock(&tasklist_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 359 | return error; |
| 360 | } |
| 361 | |
Roland McGrath | e16b278 | 2008-04-20 13:10:12 -0700 | [diff] [blame] | 362 | static int ptrace_setsiginfo(struct task_struct *child, const siginfo_t *info) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 363 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 364 | int error = -ESRCH; |
| 365 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 366 | read_lock(&tasklist_lock); |
| 367 | if (likely(child->sighand != NULL)) { |
| 368 | error = -EINVAL; |
| 369 | spin_lock_irq(&child->sighand->siglock); |
| 370 | if (likely(child->last_siginfo != NULL)) { |
Roland McGrath | e16b278 | 2008-04-20 13:10:12 -0700 | [diff] [blame] | 371 | *child->last_siginfo = *info; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 372 | error = 0; |
| 373 | } |
| 374 | spin_unlock_irq(&child->sighand->siglock); |
| 375 | } |
| 376 | read_unlock(&tasklist_lock); |
| 377 | return error; |
| 378 | } |
| 379 | |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 380 | |
| 381 | #ifdef PTRACE_SINGLESTEP |
| 382 | #define is_singlestep(request) ((request) == PTRACE_SINGLESTEP) |
| 383 | #else |
| 384 | #define is_singlestep(request) 0 |
| 385 | #endif |
| 386 | |
Roland McGrath | 5b88abb | 2008-01-30 13:30:53 +0100 | [diff] [blame] | 387 | #ifdef PTRACE_SINGLEBLOCK |
| 388 | #define is_singleblock(request) ((request) == PTRACE_SINGLEBLOCK) |
| 389 | #else |
| 390 | #define is_singleblock(request) 0 |
| 391 | #endif |
| 392 | |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 393 | #ifdef PTRACE_SYSEMU |
| 394 | #define is_sysemu_singlestep(request) ((request) == PTRACE_SYSEMU_SINGLESTEP) |
| 395 | #else |
| 396 | #define is_sysemu_singlestep(request) 0 |
| 397 | #endif |
| 398 | |
| 399 | static int ptrace_resume(struct task_struct *child, long request, long data) |
| 400 | { |
| 401 | if (!valid_signal(data)) |
| 402 | return -EIO; |
| 403 | |
| 404 | if (request == PTRACE_SYSCALL) |
| 405 | set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
| 406 | else |
| 407 | clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
| 408 | |
| 409 | #ifdef TIF_SYSCALL_EMU |
| 410 | if (request == PTRACE_SYSEMU || request == PTRACE_SYSEMU_SINGLESTEP) |
| 411 | set_tsk_thread_flag(child, TIF_SYSCALL_EMU); |
| 412 | else |
| 413 | clear_tsk_thread_flag(child, TIF_SYSCALL_EMU); |
| 414 | #endif |
| 415 | |
Roland McGrath | 5b88abb | 2008-01-30 13:30:53 +0100 | [diff] [blame] | 416 | if (is_singleblock(request)) { |
| 417 | if (unlikely(!arch_has_block_step())) |
| 418 | return -EIO; |
| 419 | user_enable_block_step(child); |
| 420 | } else if (is_singlestep(request) || is_sysemu_singlestep(request)) { |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 421 | if (unlikely(!arch_has_single_step())) |
| 422 | return -EIO; |
| 423 | user_enable_single_step(child); |
| 424 | } |
| 425 | else |
| 426 | user_disable_single_step(child); |
| 427 | |
| 428 | child->exit_code = data; |
| 429 | wake_up_process(child); |
| 430 | |
| 431 | return 0; |
| 432 | } |
| 433 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 434 | int ptrace_request(struct task_struct *child, long request, |
| 435 | long addr, long data) |
| 436 | { |
| 437 | int ret = -EIO; |
Roland McGrath | e16b278 | 2008-04-20 13:10:12 -0700 | [diff] [blame] | 438 | siginfo_t siginfo; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 439 | |
| 440 | switch (request) { |
Roland McGrath | 16c3e38 | 2008-01-30 13:31:47 +0100 | [diff] [blame] | 441 | case PTRACE_PEEKTEXT: |
| 442 | case PTRACE_PEEKDATA: |
| 443 | return generic_ptrace_peekdata(child, addr, data); |
| 444 | case PTRACE_POKETEXT: |
| 445 | case PTRACE_POKEDATA: |
| 446 | return generic_ptrace_pokedata(child, addr, data); |
| 447 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 448 | #ifdef PTRACE_OLDSETOPTIONS |
| 449 | case PTRACE_OLDSETOPTIONS: |
| 450 | #endif |
| 451 | case PTRACE_SETOPTIONS: |
| 452 | ret = ptrace_setoptions(child, data); |
| 453 | break; |
| 454 | case PTRACE_GETEVENTMSG: |
| 455 | ret = put_user(child->ptrace_message, (unsigned long __user *) data); |
| 456 | break; |
Roland McGrath | e16b278 | 2008-04-20 13:10:12 -0700 | [diff] [blame] | 457 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 458 | case PTRACE_GETSIGINFO: |
Roland McGrath | e16b278 | 2008-04-20 13:10:12 -0700 | [diff] [blame] | 459 | ret = ptrace_getsiginfo(child, &siginfo); |
| 460 | if (!ret) |
| 461 | ret = copy_siginfo_to_user((siginfo_t __user *) data, |
| 462 | &siginfo); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 463 | break; |
Roland McGrath | e16b278 | 2008-04-20 13:10:12 -0700 | [diff] [blame] | 464 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 465 | case PTRACE_SETSIGINFO: |
Roland McGrath | e16b278 | 2008-04-20 13:10:12 -0700 | [diff] [blame] | 466 | if (copy_from_user(&siginfo, (siginfo_t __user *) data, |
| 467 | sizeof siginfo)) |
| 468 | ret = -EFAULT; |
| 469 | else |
| 470 | ret = ptrace_setsiginfo(child, &siginfo); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 471 | break; |
Roland McGrath | e16b278 | 2008-04-20 13:10:12 -0700 | [diff] [blame] | 472 | |
Alexey Dobriyan | 1bcf548 | 2007-10-16 01:23:45 -0700 | [diff] [blame] | 473 | case PTRACE_DETACH: /* detach a process that was attached. */ |
| 474 | ret = ptrace_detach(child, data); |
| 475 | break; |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 476 | |
| 477 | #ifdef PTRACE_SINGLESTEP |
| 478 | case PTRACE_SINGLESTEP: |
| 479 | #endif |
Roland McGrath | 5b88abb | 2008-01-30 13:30:53 +0100 | [diff] [blame] | 480 | #ifdef PTRACE_SINGLEBLOCK |
| 481 | case PTRACE_SINGLEBLOCK: |
| 482 | #endif |
Roland McGrath | 36df29d | 2008-01-30 13:30:51 +0100 | [diff] [blame] | 483 | #ifdef PTRACE_SYSEMU |
| 484 | case PTRACE_SYSEMU: |
| 485 | case PTRACE_SYSEMU_SINGLESTEP: |
| 486 | #endif |
| 487 | case PTRACE_SYSCALL: |
| 488 | case PTRACE_CONT: |
| 489 | return ptrace_resume(child, request, data); |
| 490 | |
| 491 | case PTRACE_KILL: |
| 492 | if (child->exit_state) /* already dead */ |
| 493 | return 0; |
| 494 | return ptrace_resume(child, request, SIGKILL); |
| 495 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 496 | default: |
| 497 | break; |
| 498 | } |
| 499 | |
| 500 | return ret; |
| 501 | } |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 502 | |
Christoph Hellwig | 6b9c7ed | 2006-01-08 01:02:33 -0800 | [diff] [blame] | 503 | /** |
| 504 | * ptrace_traceme -- helper for PTRACE_TRACEME |
| 505 | * |
| 506 | * Performs checks and sets PT_PTRACED. |
| 507 | * Should be used by all ptrace implementations for PTRACE_TRACEME. |
| 508 | */ |
| 509 | int ptrace_traceme(void) |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 510 | { |
Linus Torvalds | f5b40e3 | 2006-05-07 10:49:33 -0700 | [diff] [blame] | 511 | int ret = -EPERM; |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 512 | |
| 513 | /* |
Christoph Hellwig | 6b9c7ed | 2006-01-08 01:02:33 -0800 | [diff] [blame] | 514 | * Are we already being traced? |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 515 | */ |
Roland McGrath | f470021 | 2008-03-24 18:36:23 -0700 | [diff] [blame] | 516 | repeat: |
Linus Torvalds | f5b40e3 | 2006-05-07 10:49:33 -0700 | [diff] [blame] | 517 | task_lock(current); |
| 518 | if (!(current->ptrace & PT_PTRACED)) { |
Roland McGrath | f470021 | 2008-03-24 18:36:23 -0700 | [diff] [blame] | 519 | /* |
| 520 | * See ptrace_attach() comments about the locking here. |
| 521 | */ |
| 522 | unsigned long flags; |
| 523 | if (!write_trylock_irqsave(&tasklist_lock, flags)) { |
| 524 | task_unlock(current); |
| 525 | do { |
| 526 | cpu_relax(); |
| 527 | } while (!write_can_lock(&tasklist_lock)); |
| 528 | goto repeat; |
| 529 | } |
| 530 | |
David Howells | 5cd9c58 | 2008-08-14 11:37:28 +0100 | [diff] [blame] | 531 | ret = security_ptrace_traceme(current->parent); |
Roland McGrath | f470021 | 2008-03-24 18:36:23 -0700 | [diff] [blame] | 532 | |
Linus Torvalds | f5b40e3 | 2006-05-07 10:49:33 -0700 | [diff] [blame] | 533 | /* |
| 534 | * Set the ptrace bit in the process ptrace flags. |
Roland McGrath | f470021 | 2008-03-24 18:36:23 -0700 | [diff] [blame] | 535 | * Then link us on our parent's ptraced list. |
Linus Torvalds | f5b40e3 | 2006-05-07 10:49:33 -0700 | [diff] [blame] | 536 | */ |
Roland McGrath | f470021 | 2008-03-24 18:36:23 -0700 | [diff] [blame] | 537 | if (!ret) { |
Linus Torvalds | f5b40e3 | 2006-05-07 10:49:33 -0700 | [diff] [blame] | 538 | current->ptrace |= PT_PTRACED; |
Roland McGrath | f470021 | 2008-03-24 18:36:23 -0700 | [diff] [blame] | 539 | __ptrace_link(current, current->real_parent); |
| 540 | } |
| 541 | |
| 542 | write_unlock_irqrestore(&tasklist_lock, flags); |
Linus Torvalds | f5b40e3 | 2006-05-07 10:49:33 -0700 | [diff] [blame] | 543 | } |
| 544 | task_unlock(current); |
| 545 | return ret; |
Christoph Hellwig | 6b9c7ed | 2006-01-08 01:02:33 -0800 | [diff] [blame] | 546 | } |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 547 | |
Christoph Hellwig | 6b9c7ed | 2006-01-08 01:02:33 -0800 | [diff] [blame] | 548 | /** |
| 549 | * ptrace_get_task_struct -- grab a task struct reference for ptrace |
| 550 | * @pid: process id to grab a task_struct reference of |
| 551 | * |
| 552 | * This function is a helper for ptrace implementations. It checks |
| 553 | * permissions and then grabs a task struct for use of the actual |
| 554 | * ptrace implementation. |
| 555 | * |
| 556 | * Returns the task_struct for @pid or an ERR_PTR() on failure. |
| 557 | */ |
| 558 | struct task_struct *ptrace_get_task_struct(pid_t pid) |
| 559 | { |
| 560 | struct task_struct *child; |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 561 | |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 562 | read_lock(&tasklist_lock); |
Pavel Emelyanov | 228ebcb | 2007-10-18 23:40:16 -0700 | [diff] [blame] | 563 | child = find_task_by_vpid(pid); |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 564 | if (child) |
| 565 | get_task_struct(child); |
Sukadev Bhattiprolu | f400e19 | 2006-09-29 02:00:07 -0700 | [diff] [blame] | 566 | |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 567 | read_unlock(&tasklist_lock); |
| 568 | if (!child) |
Christoph Hellwig | 6b9c7ed | 2006-01-08 01:02:33 -0800 | [diff] [blame] | 569 | return ERR_PTR(-ESRCH); |
| 570 | return child; |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 571 | } |
| 572 | |
Christoph Hellwig | 0ac1555 | 2007-10-16 01:26:37 -0700 | [diff] [blame] | 573 | #ifndef arch_ptrace_attach |
| 574 | #define arch_ptrace_attach(child) do { } while (0) |
| 575 | #endif |
| 576 | |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 577 | asmlinkage long sys_ptrace(long request, long pid, long addr, long data) |
| 578 | { |
| 579 | struct task_struct *child; |
| 580 | long ret; |
| 581 | |
| 582 | /* |
| 583 | * This lock_kernel fixes a subtle race with suid exec |
| 584 | */ |
| 585 | lock_kernel(); |
Christoph Hellwig | 6b9c7ed | 2006-01-08 01:02:33 -0800 | [diff] [blame] | 586 | if (request == PTRACE_TRACEME) { |
| 587 | ret = ptrace_traceme(); |
Haavard Skinnemoen | 6ea6dd9 | 2007-11-27 13:02:40 +0100 | [diff] [blame] | 588 | if (!ret) |
| 589 | arch_ptrace_attach(current); |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 590 | goto out; |
Christoph Hellwig | 6b9c7ed | 2006-01-08 01:02:33 -0800 | [diff] [blame] | 591 | } |
| 592 | |
| 593 | child = ptrace_get_task_struct(pid); |
| 594 | if (IS_ERR(child)) { |
| 595 | ret = PTR_ERR(child); |
| 596 | goto out; |
| 597 | } |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 598 | |
| 599 | if (request == PTRACE_ATTACH) { |
| 600 | ret = ptrace_attach(child); |
Christoph Hellwig | 0ac1555 | 2007-10-16 01:26:37 -0700 | [diff] [blame] | 601 | /* |
| 602 | * Some architectures need to do book-keeping after |
| 603 | * a ptrace attach. |
| 604 | */ |
| 605 | if (!ret) |
| 606 | arch_ptrace_attach(child); |
Christoph Hellwig | 005f18d | 2005-11-13 16:06:33 -0800 | [diff] [blame] | 607 | goto out_put_task_struct; |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 608 | } |
| 609 | |
| 610 | ret = ptrace_check_attach(child, request == PTRACE_KILL); |
| 611 | if (ret < 0) |
| 612 | goto out_put_task_struct; |
| 613 | |
| 614 | ret = arch_ptrace(child, request, addr, data); |
| 615 | if (ret < 0) |
| 616 | goto out_put_task_struct; |
| 617 | |
| 618 | out_put_task_struct: |
| 619 | put_task_struct(child); |
| 620 | out: |
| 621 | unlock_kernel(); |
| 622 | return ret; |
| 623 | } |
Alexey Dobriyan | 7664732 | 2007-07-17 04:03:43 -0700 | [diff] [blame] | 624 | |
| 625 | int generic_ptrace_peekdata(struct task_struct *tsk, long addr, long data) |
| 626 | { |
| 627 | unsigned long tmp; |
| 628 | int copied; |
| 629 | |
| 630 | copied = access_process_vm(tsk, addr, &tmp, sizeof(tmp), 0); |
| 631 | if (copied != sizeof(tmp)) |
| 632 | return -EIO; |
| 633 | return put_user(tmp, (unsigned long __user *)data); |
| 634 | } |
Alexey Dobriyan | f284ce7 | 2007-07-17 04:03:44 -0700 | [diff] [blame] | 635 | |
| 636 | int generic_ptrace_pokedata(struct task_struct *tsk, long addr, long data) |
| 637 | { |
| 638 | int copied; |
| 639 | |
| 640 | copied = access_process_vm(tsk, addr, &data, sizeof(data), 1); |
| 641 | return (copied == sizeof(data)) ? 0 : -EIO; |
| 642 | } |
Roland McGrath | 032d82d | 2008-01-30 13:31:47 +0100 | [diff] [blame] | 643 | |
Christoph Hellwig | 96b8936 | 2008-11-25 08:10:03 +0100 | [diff] [blame] | 644 | #if defined CONFIG_COMPAT |
Roland McGrath | 032d82d | 2008-01-30 13:31:47 +0100 | [diff] [blame] | 645 | #include <linux/compat.h> |
| 646 | |
| 647 | int compat_ptrace_request(struct task_struct *child, compat_long_t request, |
| 648 | compat_ulong_t addr, compat_ulong_t data) |
| 649 | { |
| 650 | compat_ulong_t __user *datap = compat_ptr(data); |
| 651 | compat_ulong_t word; |
Roland McGrath | e16b278 | 2008-04-20 13:10:12 -0700 | [diff] [blame] | 652 | siginfo_t siginfo; |
Roland McGrath | 032d82d | 2008-01-30 13:31:47 +0100 | [diff] [blame] | 653 | int ret; |
| 654 | |
| 655 | switch (request) { |
| 656 | case PTRACE_PEEKTEXT: |
| 657 | case PTRACE_PEEKDATA: |
| 658 | ret = access_process_vm(child, addr, &word, sizeof(word), 0); |
| 659 | if (ret != sizeof(word)) |
| 660 | ret = -EIO; |
| 661 | else |
| 662 | ret = put_user(word, datap); |
| 663 | break; |
| 664 | |
| 665 | case PTRACE_POKETEXT: |
| 666 | case PTRACE_POKEDATA: |
| 667 | ret = access_process_vm(child, addr, &data, sizeof(data), 1); |
| 668 | ret = (ret != sizeof(data) ? -EIO : 0); |
| 669 | break; |
| 670 | |
| 671 | case PTRACE_GETEVENTMSG: |
| 672 | ret = put_user((compat_ulong_t) child->ptrace_message, datap); |
| 673 | break; |
| 674 | |
Roland McGrath | e16b278 | 2008-04-20 13:10:12 -0700 | [diff] [blame] | 675 | case PTRACE_GETSIGINFO: |
| 676 | ret = ptrace_getsiginfo(child, &siginfo); |
| 677 | if (!ret) |
| 678 | ret = copy_siginfo_to_user32( |
| 679 | (struct compat_siginfo __user *) datap, |
| 680 | &siginfo); |
| 681 | break; |
| 682 | |
| 683 | case PTRACE_SETSIGINFO: |
| 684 | memset(&siginfo, 0, sizeof siginfo); |
| 685 | if (copy_siginfo_from_user32( |
| 686 | &siginfo, (struct compat_siginfo __user *) datap)) |
| 687 | ret = -EFAULT; |
| 688 | else |
| 689 | ret = ptrace_setsiginfo(child, &siginfo); |
| 690 | break; |
| 691 | |
Roland McGrath | 032d82d | 2008-01-30 13:31:47 +0100 | [diff] [blame] | 692 | default: |
| 693 | ret = ptrace_request(child, request, addr, data); |
| 694 | } |
| 695 | |
| 696 | return ret; |
| 697 | } |
Roland McGrath | c269f19 | 2008-01-30 13:31:48 +0100 | [diff] [blame] | 698 | |
Roland McGrath | c269f19 | 2008-01-30 13:31:48 +0100 | [diff] [blame] | 699 | asmlinkage long compat_sys_ptrace(compat_long_t request, compat_long_t pid, |
| 700 | compat_long_t addr, compat_long_t data) |
| 701 | { |
| 702 | struct task_struct *child; |
| 703 | long ret; |
| 704 | |
| 705 | /* |
| 706 | * This lock_kernel fixes a subtle race with suid exec |
| 707 | */ |
| 708 | lock_kernel(); |
| 709 | if (request == PTRACE_TRACEME) { |
| 710 | ret = ptrace_traceme(); |
| 711 | goto out; |
| 712 | } |
| 713 | |
| 714 | child = ptrace_get_task_struct(pid); |
| 715 | if (IS_ERR(child)) { |
| 716 | ret = PTR_ERR(child); |
| 717 | goto out; |
| 718 | } |
| 719 | |
| 720 | if (request == PTRACE_ATTACH) { |
| 721 | ret = ptrace_attach(child); |
| 722 | /* |
| 723 | * Some architectures need to do book-keeping after |
| 724 | * a ptrace attach. |
| 725 | */ |
| 726 | if (!ret) |
| 727 | arch_ptrace_attach(child); |
| 728 | goto out_put_task_struct; |
| 729 | } |
| 730 | |
| 731 | ret = ptrace_check_attach(child, request == PTRACE_KILL); |
| 732 | if (!ret) |
| 733 | ret = compat_arch_ptrace(child, request, addr, data); |
| 734 | |
| 735 | out_put_task_struct: |
| 736 | put_task_struct(child); |
| 737 | out: |
| 738 | unlock_kernel(); |
| 739 | return ret; |
| 740 | } |
Christoph Hellwig | 96b8936 | 2008-11-25 08:10:03 +0100 | [diff] [blame] | 741 | #endif /* CONFIG_COMPAT */ |