11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * linux/kernel/ptrace.c 31da177e4SLinus Torvalds * 41da177e4SLinus Torvalds * (C) Copyright 1999 Linus Torvalds 51da177e4SLinus Torvalds * 61da177e4SLinus Torvalds * Common interfaces for "ptrace()" which we do not want 71da177e4SLinus Torvalds * to continually duplicate across every architecture. 81da177e4SLinus Torvalds */ 91da177e4SLinus Torvalds 10c59ede7bSRandy.Dunlap #include <linux/capability.h> 119984de1aSPaul Gortmaker #include <linux/export.h> 121da177e4SLinus Torvalds #include <linux/sched.h> 136e84f315SIngo Molnar #include <linux/sched/mm.h> 14f7ccbae4SIngo Molnar #include <linux/sched/coredump.h> 1529930025SIngo Molnar #include <linux/sched/task.h> 161da177e4SLinus Torvalds #include <linux/errno.h> 171da177e4SLinus Torvalds #include <linux/mm.h> 181da177e4SLinus Torvalds #include <linux/highmem.h> 191da177e4SLinus Torvalds #include <linux/pagemap.h> 201da177e4SLinus Torvalds #include <linux/ptrace.h> 211da177e4SLinus Torvalds #include <linux/security.h> 227ed20e1aSJesper Juhl #include <linux/signal.h> 23a27bb332SKent Overstreet #include <linux/uio.h> 24a5cb013dSAl Viro #include <linux/audit.h> 25b488893aSPavel Emelyanov #include <linux/pid_namespace.h> 26f17d30a8SAdrian Bunk #include <linux/syscalls.h> 273a709703SRoland McGrath #include <linux/uaccess.h> 282225a122SSuresh Siddha #include <linux/regset.h> 29bf26c018SFrederic Weisbecker #include <linux/hw_breakpoint.h> 30f701e5b7SVladimir Zapolskiy #include <linux/cn_proc.h> 3184c751bdSAndrey Vagin #include <linux/compat.h> 321da177e4SLinus Torvalds 3384d77d3fSEric W. Biederman /* 3484d77d3fSEric W. Biederman * Access another process' address space via ptrace. 3584d77d3fSEric W. Biederman * Source/target buffer must be kernel space, 3684d77d3fSEric W. Biederman * Do not walk the page table directly, use get_user_pages 3784d77d3fSEric W. Biederman */ 3884d77d3fSEric W. Biederman int ptrace_access_vm(struct task_struct *tsk, unsigned long addr, 3984d77d3fSEric W. Biederman void *buf, int len, unsigned int gup_flags) 4084d77d3fSEric W. Biederman { 4184d77d3fSEric W. Biederman struct mm_struct *mm; 4284d77d3fSEric W. Biederman int ret; 4384d77d3fSEric W. Biederman 4484d77d3fSEric W. Biederman mm = get_task_mm(tsk); 4584d77d3fSEric W. Biederman if (!mm) 4684d77d3fSEric W. Biederman return 0; 4784d77d3fSEric W. Biederman 4884d77d3fSEric W. Biederman if (!tsk->ptrace || 4984d77d3fSEric W. Biederman (current != tsk->parent) || 5084d77d3fSEric W. Biederman ((get_dumpable(mm) != SUID_DUMP_USER) && 5184d77d3fSEric W. Biederman !ptracer_capable(tsk, mm->user_ns))) { 5284d77d3fSEric W. Biederman mmput(mm); 5384d77d3fSEric W. Biederman return 0; 5484d77d3fSEric W. Biederman } 5584d77d3fSEric W. Biederman 5684d77d3fSEric W. Biederman ret = __access_remote_vm(tsk, mm, addr, buf, len, gup_flags); 5784d77d3fSEric W. Biederman mmput(mm); 5884d77d3fSEric W. Biederman 5984d77d3fSEric W. Biederman return ret; 6084d77d3fSEric W. Biederman } 6184d77d3fSEric W. Biederman 62bf53de90SMarkus Metzger 63c70d9d80SEric W. Biederman void __ptrace_link(struct task_struct *child, struct task_struct *new_parent, 64c70d9d80SEric W. Biederman const struct cred *ptracer_cred) 65c70d9d80SEric W. Biederman { 66c70d9d80SEric W. Biederman BUG_ON(!list_empty(&child->ptrace_entry)); 67c70d9d80SEric W. Biederman list_add(&child->ptrace_entry, &new_parent->ptraced); 68c70d9d80SEric W. Biederman child->parent = new_parent; 69c70d9d80SEric W. Biederman child->ptracer_cred = get_cred(ptracer_cred); 70c70d9d80SEric W. Biederman } 71c70d9d80SEric W. Biederman 72bf53de90SMarkus Metzger /* 731da177e4SLinus Torvalds * ptrace a task: make the debugger its new parent and 741da177e4SLinus Torvalds * move it to the ptrace list. 751da177e4SLinus Torvalds * 761da177e4SLinus Torvalds * Must be called with the tasklist lock write-held. 771da177e4SLinus Torvalds */ 78c70d9d80SEric W. Biederman static void ptrace_link(struct task_struct *child, struct task_struct *new_parent) 791da177e4SLinus Torvalds { 8064b875f7SEric W. Biederman rcu_read_lock(); 81c70d9d80SEric W. Biederman __ptrace_link(child, new_parent, __task_cred(new_parent)); 8264b875f7SEric W. Biederman rcu_read_unlock(); 831da177e4SLinus Torvalds } 841da177e4SLinus Torvalds 85e3bd058fSTejun Heo /** 86e3bd058fSTejun Heo * __ptrace_unlink - unlink ptracee and restore its execution state 87e3bd058fSTejun Heo * @child: ptracee to be unlinked 881da177e4SLinus Torvalds * 890e9f0a4aSTejun Heo * Remove @child from the ptrace list, move it back to the original parent, 900e9f0a4aSTejun Heo * and restore the execution state so that it conforms to the group stop 910e9f0a4aSTejun Heo * state. 920e9f0a4aSTejun Heo * 930e9f0a4aSTejun Heo * Unlinking can happen via two paths - explicit PTRACE_DETACH or ptracer 940e9f0a4aSTejun Heo * exiting. For PTRACE_DETACH, unless the ptracee has been killed between 950e9f0a4aSTejun Heo * ptrace_check_attach() and here, it's guaranteed to be in TASK_TRACED. 960e9f0a4aSTejun Heo * If the ptracer is exiting, the ptracee can be in any state. 970e9f0a4aSTejun Heo * 980e9f0a4aSTejun Heo * After detach, the ptracee should be in a state which conforms to the 990e9f0a4aSTejun Heo * group stop. If the group is stopped or in the process of stopping, the 1000e9f0a4aSTejun Heo * ptracee should be put into TASK_STOPPED; otherwise, it should be woken 1010e9f0a4aSTejun Heo * up from TASK_TRACED. 1020e9f0a4aSTejun Heo * 1030e9f0a4aSTejun Heo * If the ptracee is in TASK_TRACED and needs to be moved to TASK_STOPPED, 1040e9f0a4aSTejun Heo * it goes through TRACED -> RUNNING -> STOPPED transition which is similar 1050e9f0a4aSTejun Heo * to but in the opposite direction of what happens while attaching to a 1060e9f0a4aSTejun Heo * stopped task. However, in this direction, the intermediate RUNNING 1070e9f0a4aSTejun Heo * state is not hidden even from the current ptracer and if it immediately 1080e9f0a4aSTejun Heo * re-attaches and performs a WNOHANG wait(2), it may fail. 109e3bd058fSTejun Heo * 110e3bd058fSTejun Heo * CONTEXT: 111e3bd058fSTejun Heo * write_lock_irq(tasklist_lock) 1121da177e4SLinus Torvalds */ 11336c8b586SIngo Molnar void __ptrace_unlink(struct task_struct *child) 1141da177e4SLinus Torvalds { 11564b875f7SEric W. Biederman const struct cred *old_cred; 1165ecfbae0SOleg Nesterov BUG_ON(!child->ptrace); 1175ecfbae0SOleg Nesterov 1180a5bf409SAles Novak clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); 1190a5bf409SAles Novak 1201da177e4SLinus Torvalds child->parent = child->real_parent; 121f470021aSRoland McGrath list_del_init(&child->ptrace_entry); 12264b875f7SEric W. Biederman old_cred = child->ptracer_cred; 12364b875f7SEric W. Biederman child->ptracer_cred = NULL; 12464b875f7SEric W. Biederman put_cred(old_cred); 1251da177e4SLinus Torvalds 1261da177e4SLinus Torvalds spin_lock(&child->sighand->siglock); 1271333ab03SOleg Nesterov child->ptrace = 0; 1281da177e4SLinus Torvalds /* 12973ddff2bSTejun Heo * Clear all pending traps and TRAPPING. TRAPPING should be 13073ddff2bSTejun Heo * cleared regardless of JOBCTL_STOP_PENDING. Do it explicitly. 13173ddff2bSTejun Heo */ 13273ddff2bSTejun Heo task_clear_jobctl_pending(child, JOBCTL_TRAP_MASK); 13373ddff2bSTejun Heo task_clear_jobctl_trapping(child); 13473ddff2bSTejun Heo 13573ddff2bSTejun Heo /* 136a8f072c1STejun Heo * Reinstate JOBCTL_STOP_PENDING if group stop is in effect and 1370e9f0a4aSTejun Heo * @child isn't dead. 1381da177e4SLinus Torvalds */ 1390e9f0a4aSTejun Heo if (!(child->flags & PF_EXITING) && 1400e9f0a4aSTejun Heo (child->signal->flags & SIGNAL_STOP_STOPPED || 1418a88951bSOleg Nesterov child->signal->group_stop_count)) { 142a8f072c1STejun Heo child->jobctl |= JOBCTL_STOP_PENDING; 1430e9f0a4aSTejun Heo 1440e9f0a4aSTejun Heo /* 1458a88951bSOleg Nesterov * This is only possible if this thread was cloned by the 1468a88951bSOleg Nesterov * traced task running in the stopped group, set the signal 1478a88951bSOleg Nesterov * for the future reports. 1488a88951bSOleg Nesterov * FIXME: we should change ptrace_init_task() to handle this 1498a88951bSOleg Nesterov * case. 1508a88951bSOleg Nesterov */ 1518a88951bSOleg Nesterov if (!(child->jobctl & JOBCTL_STOP_SIGMASK)) 1528a88951bSOleg Nesterov child->jobctl |= SIGSTOP; 1538a88951bSOleg Nesterov } 1548a88951bSOleg Nesterov 1558a88951bSOleg Nesterov /* 1560e9f0a4aSTejun Heo * If transition to TASK_STOPPED is pending or in TASK_TRACED, kick 1570e9f0a4aSTejun Heo * @child in the butt. Note that @resume should be used iff @child 1580e9f0a4aSTejun Heo * is in TASK_TRACED; otherwise, we might unduly disrupt 1590e9f0a4aSTejun Heo * TASK_KILLABLE sleeps. 1600e9f0a4aSTejun Heo */ 161a8f072c1STejun Heo if (child->jobctl & JOBCTL_STOP_PENDING || task_is_traced(child)) 162910ffdb1SOleg Nesterov ptrace_signal_wake_up(child, true); 1630e9f0a4aSTejun Heo 1641da177e4SLinus Torvalds spin_unlock(&child->sighand->siglock); 1651da177e4SLinus Torvalds } 1661da177e4SLinus Torvalds 1679899d11fSOleg Nesterov /* Ensure that nothing can wake it up, even SIGKILL */ 1689899d11fSOleg Nesterov static bool ptrace_freeze_traced(struct task_struct *task) 1699899d11fSOleg Nesterov { 1709899d11fSOleg Nesterov bool ret = false; 1719899d11fSOleg Nesterov 1729899d11fSOleg Nesterov /* Lockless, nobody but us can set this flag */ 1739899d11fSOleg Nesterov if (task->jobctl & JOBCTL_LISTENING) 1749899d11fSOleg Nesterov return ret; 1759899d11fSOleg Nesterov 1769899d11fSOleg Nesterov spin_lock_irq(&task->sighand->siglock); 1779899d11fSOleg Nesterov if (task_is_traced(task) && !__fatal_signal_pending(task)) { 1789899d11fSOleg Nesterov task->state = __TASK_TRACED; 1799899d11fSOleg Nesterov ret = true; 1809899d11fSOleg Nesterov } 1819899d11fSOleg Nesterov spin_unlock_irq(&task->sighand->siglock); 1829899d11fSOleg Nesterov 1839899d11fSOleg Nesterov return ret; 1849899d11fSOleg Nesterov } 1859899d11fSOleg Nesterov 1869899d11fSOleg Nesterov static void ptrace_unfreeze_traced(struct task_struct *task) 1879899d11fSOleg Nesterov { 1889899d11fSOleg Nesterov if (task->state != __TASK_TRACED) 1899899d11fSOleg Nesterov return; 1909899d11fSOleg Nesterov 1919899d11fSOleg Nesterov WARN_ON(!task->ptrace || task->parent != current); 1929899d11fSOleg Nesterov 1935402e97aSbsegall@google.com /* 1945402e97aSbsegall@google.com * PTRACE_LISTEN can allow ptrace_trap_notify to wake us up remotely. 1955402e97aSbsegall@google.com * Recheck state under the lock to close this race. 1965402e97aSbsegall@google.com */ 1979899d11fSOleg Nesterov spin_lock_irq(&task->sighand->siglock); 1985402e97aSbsegall@google.com if (task->state == __TASK_TRACED) { 1999899d11fSOleg Nesterov if (__fatal_signal_pending(task)) 2009899d11fSOleg Nesterov wake_up_state(task, __TASK_TRACED); 2019899d11fSOleg Nesterov else 2029899d11fSOleg Nesterov task->state = TASK_TRACED; 2035402e97aSbsegall@google.com } 2049899d11fSOleg Nesterov spin_unlock_irq(&task->sighand->siglock); 2059899d11fSOleg Nesterov } 2069899d11fSOleg Nesterov 207755e276bSTejun Heo /** 208755e276bSTejun Heo * ptrace_check_attach - check whether ptracee is ready for ptrace operation 209755e276bSTejun Heo * @child: ptracee to check for 210755e276bSTejun Heo * @ignore_state: don't check whether @child is currently %TASK_TRACED 211755e276bSTejun Heo * 212755e276bSTejun Heo * Check whether @child is being ptraced by %current and ready for further 213755e276bSTejun Heo * ptrace operations. If @ignore_state is %false, @child also should be in 214755e276bSTejun Heo * %TASK_TRACED state and on return the child is guaranteed to be traced 215755e276bSTejun Heo * and not executing. If @ignore_state is %true, @child can be in any 216755e276bSTejun Heo * state. 217755e276bSTejun Heo * 218755e276bSTejun Heo * CONTEXT: 219755e276bSTejun Heo * Grabs and releases tasklist_lock and @child->sighand->siglock. 220755e276bSTejun Heo * 221755e276bSTejun Heo * RETURNS: 222755e276bSTejun Heo * 0 on success, -ESRCH if %child is not ready. 2231da177e4SLinus Torvalds */ 224edea0d03SOleg Nesterov static int ptrace_check_attach(struct task_struct *child, bool ignore_state) 2251da177e4SLinus Torvalds { 2261da177e4SLinus Torvalds int ret = -ESRCH; 2271da177e4SLinus Torvalds 2281da177e4SLinus Torvalds /* 2291da177e4SLinus Torvalds * We take the read lock around doing both checks to close a 2301da177e4SLinus Torvalds * possible race where someone else was tracing our child and 2311da177e4SLinus Torvalds * detached between these two checks. After this locked check, 2321da177e4SLinus Torvalds * we are sure that this is our traced child and that can only 2331da177e4SLinus Torvalds * be changed by us so it's not changing right after this. 2341da177e4SLinus Torvalds */ 2351da177e4SLinus Torvalds read_lock(&tasklist_lock); 2369899d11fSOleg Nesterov if (child->ptrace && child->parent == current) { 2379899d11fSOleg Nesterov WARN_ON(child->state == __TASK_TRACED); 238c0c0b649SOleg Nesterov /* 239c0c0b649SOleg Nesterov * child->sighand can't be NULL, release_task() 240c0c0b649SOleg Nesterov * does ptrace_unlink() before __exit_signal(). 241c0c0b649SOleg Nesterov */ 2429899d11fSOleg Nesterov if (ignore_state || ptrace_freeze_traced(child)) 243321fb561SOleg Nesterov ret = 0; 2441da177e4SLinus Torvalds } 2451da177e4SLinus Torvalds read_unlock(&tasklist_lock); 2461da177e4SLinus Torvalds 2479899d11fSOleg Nesterov if (!ret && !ignore_state) { 2489899d11fSOleg Nesterov if (!wait_task_inactive(child, __TASK_TRACED)) { 2499899d11fSOleg Nesterov /* 2509899d11fSOleg Nesterov * This can only happen if may_ptrace_stop() fails and 2519899d11fSOleg Nesterov * ptrace_stop() changes ->state back to TASK_RUNNING, 2529899d11fSOleg Nesterov * so we should not worry about leaking __TASK_TRACED. 2539899d11fSOleg Nesterov */ 2549899d11fSOleg Nesterov WARN_ON(child->state == __TASK_TRACED); 2559899d11fSOleg Nesterov ret = -ESRCH; 2569899d11fSOleg Nesterov } 2579899d11fSOleg Nesterov } 2581da177e4SLinus Torvalds 2591da177e4SLinus Torvalds return ret; 2601da177e4SLinus Torvalds } 2611da177e4SLinus Torvalds 26269f594a3SEric Paris static int ptrace_has_cap(struct user_namespace *ns, unsigned int mode) 26369f594a3SEric Paris { 26469f594a3SEric Paris if (mode & PTRACE_MODE_NOAUDIT) 26569f594a3SEric Paris return has_ns_capability_noaudit(current, ns, CAP_SYS_PTRACE); 26669f594a3SEric Paris else 26769f594a3SEric Paris return has_ns_capability(current, ns, CAP_SYS_PTRACE); 26869f594a3SEric Paris } 26969f594a3SEric Paris 2709f99798fSTetsuo Handa /* Returns 0 on success, -errno on denial. */ 2719f99798fSTetsuo Handa static int __ptrace_may_access(struct task_struct *task, unsigned int mode) 272ab8d11beSMiklos Szeredi { 273c69e8d9cSDavid Howells const struct cred *cred = current_cred(), *tcred; 274bfedb589SEric W. Biederman struct mm_struct *mm; 275caaee623SJann Horn kuid_t caller_uid; 276caaee623SJann Horn kgid_t caller_gid; 277caaee623SJann Horn 278caaee623SJann Horn if (!(mode & PTRACE_MODE_FSCREDS) == !(mode & PTRACE_MODE_REALCREDS)) { 279caaee623SJann Horn WARN(1, "denying ptrace access check without PTRACE_MODE_*CREDS\n"); 280caaee623SJann Horn return -EPERM; 281caaee623SJann Horn } 282b6dff3ecSDavid Howells 283df26c40eSEric W. Biederman /* May we inspect the given task? 284df26c40eSEric W. Biederman * This check is used both for attaching with ptrace 285df26c40eSEric W. Biederman * and for allowing access to sensitive information in /proc. 286df26c40eSEric W. Biederman * 287df26c40eSEric W. Biederman * ptrace_attach denies several cases that /proc allows 288df26c40eSEric W. Biederman * because setting up the necessary parent/child relationship 289df26c40eSEric W. Biederman * or halting the specified task is impossible. 290df26c40eSEric W. Biederman */ 291caaee623SJann Horn 292df26c40eSEric W. Biederman /* Don't let security modules deny introspection */ 29373af963fSMark Grondona if (same_thread_group(task, current)) 294df26c40eSEric W. Biederman return 0; 295c69e8d9cSDavid Howells rcu_read_lock(); 296caaee623SJann Horn if (mode & PTRACE_MODE_FSCREDS) { 297caaee623SJann Horn caller_uid = cred->fsuid; 298caaee623SJann Horn caller_gid = cred->fsgid; 299caaee623SJann Horn } else { 300caaee623SJann Horn /* 301caaee623SJann Horn * Using the euid would make more sense here, but something 302caaee623SJann Horn * in userland might rely on the old behavior, and this 303caaee623SJann Horn * shouldn't be a security problem since 304caaee623SJann Horn * PTRACE_MODE_REALCREDS implies that the caller explicitly 305caaee623SJann Horn * used a syscall that requests access to another process 306caaee623SJann Horn * (and not a filesystem syscall to procfs). 307caaee623SJann Horn */ 308caaee623SJann Horn caller_uid = cred->uid; 309caaee623SJann Horn caller_gid = cred->gid; 310caaee623SJann Horn } 311c69e8d9cSDavid Howells tcred = __task_cred(task); 312caaee623SJann Horn if (uid_eq(caller_uid, tcred->euid) && 313caaee623SJann Horn uid_eq(caller_uid, tcred->suid) && 314caaee623SJann Horn uid_eq(caller_uid, tcred->uid) && 315caaee623SJann Horn gid_eq(caller_gid, tcred->egid) && 316caaee623SJann Horn gid_eq(caller_gid, tcred->sgid) && 317caaee623SJann Horn gid_eq(caller_gid, tcred->gid)) 3188409cca7SSerge E. Hallyn goto ok; 319c4a4d603SEric W. Biederman if (ptrace_has_cap(tcred->user_ns, mode)) 3208409cca7SSerge E. Hallyn goto ok; 321c69e8d9cSDavid Howells rcu_read_unlock(); 322ab8d11beSMiklos Szeredi return -EPERM; 3238409cca7SSerge E. Hallyn ok: 324c69e8d9cSDavid Howells rcu_read_unlock(); 325bfedb589SEric W. Biederman mm = task->mm; 326bfedb589SEric W. Biederman if (mm && 327bfedb589SEric W. Biederman ((get_dumpable(mm) != SUID_DUMP_USER) && 328bfedb589SEric W. Biederman !ptrace_has_cap(mm->user_ns, mode))) 329ab8d11beSMiklos Szeredi return -EPERM; 330ab8d11beSMiklos Szeredi 3319e48858fSIngo Molnar return security_ptrace_access_check(task, mode); 332ab8d11beSMiklos Szeredi } 333ab8d11beSMiklos Szeredi 334006ebb40SStephen Smalley bool ptrace_may_access(struct task_struct *task, unsigned int mode) 335ab8d11beSMiklos Szeredi { 336ab8d11beSMiklos Szeredi int err; 337ab8d11beSMiklos Szeredi task_lock(task); 338006ebb40SStephen Smalley err = __ptrace_may_access(task, mode); 339ab8d11beSMiklos Szeredi task_unlock(task); 3403a709703SRoland McGrath return !err; 341ab8d11beSMiklos Szeredi } 342ab8d11beSMiklos Szeredi 3433544d72aSTejun Heo static int ptrace_attach(struct task_struct *task, long request, 344aa9147c9SDenys Vlasenko unsigned long addr, 3453544d72aSTejun Heo unsigned long flags) 3461da177e4SLinus Torvalds { 3473544d72aSTejun Heo bool seize = (request == PTRACE_SEIZE); 3481da177e4SLinus Torvalds int retval; 349f5b40e36SLinus Torvalds 3503544d72aSTejun Heo retval = -EIO; 351aa9147c9SDenys Vlasenko if (seize) { 352aa9147c9SDenys Vlasenko if (addr != 0) 3533544d72aSTejun Heo goto out; 354aa9147c9SDenys Vlasenko if (flags & ~(unsigned long)PTRACE_O_MASK) 355aa9147c9SDenys Vlasenko goto out; 356aa9147c9SDenys Vlasenko flags = PT_PTRACED | PT_SEIZED | (flags << PT_OPT_FLAG_SHIFT); 357aa9147c9SDenys Vlasenko } else { 358aa9147c9SDenys Vlasenko flags = PT_PTRACED; 359aa9147c9SDenys Vlasenko } 3603544d72aSTejun Heo 361a5cb013dSAl Viro audit_ptrace(task); 362a5cb013dSAl Viro 3631da177e4SLinus Torvalds retval = -EPERM; 364b79b7ba9SOleg Nesterov if (unlikely(task->flags & PF_KTHREAD)) 365b79b7ba9SOleg Nesterov goto out; 366bac0abd6SPavel Emelyanov if (same_thread_group(task, current)) 367f5b40e36SLinus Torvalds goto out; 368f5b40e36SLinus Torvalds 369f2f0b00aSOleg Nesterov /* 370f2f0b00aSOleg Nesterov * Protect exec's credential calculations against our interference; 37186b6c1f3SDenys Vlasenko * SUID, SGID and LSM creds get determined differently 3725e751e99SDavid Howells * under ptrace. 373d84f4f99SDavid Howells */ 374793285fcSOleg Nesterov retval = -ERESTARTNOINTR; 3759b1bf12dSKOSAKI Motohiro if (mutex_lock_interruptible(&task->signal->cred_guard_mutex)) 376d84f4f99SDavid Howells goto out; 3774b105cbbSOleg Nesterov 378f5b40e36SLinus Torvalds task_lock(task); 379caaee623SJann Horn retval = __ptrace_may_access(task, PTRACE_MODE_ATTACH_REALCREDS); 3804b105cbbSOleg Nesterov task_unlock(task); 3811da177e4SLinus Torvalds if (retval) 3824b105cbbSOleg Nesterov goto unlock_creds; 3831da177e4SLinus Torvalds 3844b105cbbSOleg Nesterov write_lock_irq(&tasklist_lock); 385b79b7ba9SOleg Nesterov retval = -EPERM; 386b79b7ba9SOleg Nesterov if (unlikely(task->exit_state)) 3874b105cbbSOleg Nesterov goto unlock_tasklist; 388f2f0b00aSOleg Nesterov if (task->ptrace) 3894b105cbbSOleg Nesterov goto unlock_tasklist; 390b79b7ba9SOleg Nesterov 3913544d72aSTejun Heo if (seize) 392aa9147c9SDenys Vlasenko flags |= PT_SEIZED; 393aa9147c9SDenys Vlasenko task->ptrace = flags; 3941da177e4SLinus Torvalds 395c70d9d80SEric W. Biederman ptrace_link(task, current); 3963544d72aSTejun Heo 3973544d72aSTejun Heo /* SEIZE doesn't trap tracee on attach */ 3983544d72aSTejun Heo if (!seize) 399079b22dcSEric W. Biederman send_sig_info(SIGSTOP, SEND_SIG_PRIV, task); 400b79b7ba9SOleg Nesterov 401d79fdd6dSTejun Heo spin_lock(&task->sighand->siglock); 402d79fdd6dSTejun Heo 403d79fdd6dSTejun Heo /* 40473ddff2bSTejun Heo * If the task is already STOPPED, set JOBCTL_TRAP_STOP and 405d79fdd6dSTejun Heo * TRAPPING, and kick it so that it transits to TRACED. TRAPPING 406d79fdd6dSTejun Heo * will be cleared if the child completes the transition or any 407d79fdd6dSTejun Heo * event which clears the group stop states happens. We'll wait 408d79fdd6dSTejun Heo * for the transition to complete before returning from this 409d79fdd6dSTejun Heo * function. 410d79fdd6dSTejun Heo * 411d79fdd6dSTejun Heo * This hides STOPPED -> RUNNING -> TRACED transition from the 412d79fdd6dSTejun Heo * attaching thread but a different thread in the same group can 413d79fdd6dSTejun Heo * still observe the transient RUNNING state. IOW, if another 414d79fdd6dSTejun Heo * thread's WNOHANG wait(2) on the stopped tracee races against 415d79fdd6dSTejun Heo * ATTACH, the wait(2) may fail due to the transient RUNNING. 416d79fdd6dSTejun Heo * 417d79fdd6dSTejun Heo * The following task_is_stopped() test is safe as both transitions 418d79fdd6dSTejun Heo * in and out of STOPPED are protected by siglock. 419d79fdd6dSTejun Heo */ 4207dd3db54STejun Heo if (task_is_stopped(task) && 42173ddff2bSTejun Heo task_set_jobctl_pending(task, JOBCTL_TRAP_STOP | JOBCTL_TRAPPING)) 422910ffdb1SOleg Nesterov signal_wake_up_state(task, __TASK_STOPPED); 423d79fdd6dSTejun Heo 424d79fdd6dSTejun Heo spin_unlock(&task->sighand->siglock); 425d79fdd6dSTejun Heo 426b79b7ba9SOleg Nesterov retval = 0; 4274b105cbbSOleg Nesterov unlock_tasklist: 4284b105cbbSOleg Nesterov write_unlock_irq(&tasklist_lock); 4294b105cbbSOleg Nesterov unlock_creds: 4309b1bf12dSKOSAKI Motohiro mutex_unlock(&task->signal->cred_guard_mutex); 431f5b40e36SLinus Torvalds out: 432f701e5b7SVladimir Zapolskiy if (!retval) { 4337c3b00e0SOleg Nesterov /* 4347c3b00e0SOleg Nesterov * We do not bother to change retval or clear JOBCTL_TRAPPING 4357c3b00e0SOleg Nesterov * if wait_on_bit() was interrupted by SIGKILL. The tracer will 4367c3b00e0SOleg Nesterov * not return to user-mode, it will exit and clear this bit in 4377c3b00e0SOleg Nesterov * __ptrace_unlink() if it wasn't already cleared by the tracee; 4387c3b00e0SOleg Nesterov * and until then nobody can ptrace this task. 4397c3b00e0SOleg Nesterov */ 4407c3b00e0SOleg Nesterov wait_on_bit(&task->jobctl, JOBCTL_TRAPPING_BIT, TASK_KILLABLE); 441f701e5b7SVladimir Zapolskiy proc_ptrace_connector(task, PTRACE_ATTACH); 442f701e5b7SVladimir Zapolskiy } 443f701e5b7SVladimir Zapolskiy 4441da177e4SLinus Torvalds return retval; 4451da177e4SLinus Torvalds } 4461da177e4SLinus Torvalds 447f2f0b00aSOleg Nesterov /** 448f2f0b00aSOleg Nesterov * ptrace_traceme -- helper for PTRACE_TRACEME 449f2f0b00aSOleg Nesterov * 450f2f0b00aSOleg Nesterov * Performs checks and sets PT_PTRACED. 451f2f0b00aSOleg Nesterov * Should be used by all ptrace implementations for PTRACE_TRACEME. 452f2f0b00aSOleg Nesterov */ 453e3e89cc5SLinus Torvalds static int ptrace_traceme(void) 454f2f0b00aSOleg Nesterov { 455f2f0b00aSOleg Nesterov int ret = -EPERM; 456f2f0b00aSOleg Nesterov 4574b105cbbSOleg Nesterov write_lock_irq(&tasklist_lock); 4584b105cbbSOleg Nesterov /* Are we already being traced? */ 459f2f0b00aSOleg Nesterov if (!current->ptrace) { 460f2f0b00aSOleg Nesterov ret = security_ptrace_traceme(current->parent); 461f2f0b00aSOleg Nesterov /* 462f2f0b00aSOleg Nesterov * Check PF_EXITING to ensure ->real_parent has not passed 463f2f0b00aSOleg Nesterov * exit_ptrace(). Otherwise we don't report the error but 464f2f0b00aSOleg Nesterov * pretend ->real_parent untraces us right after return. 465f2f0b00aSOleg Nesterov */ 466f2f0b00aSOleg Nesterov if (!ret && !(current->real_parent->flags & PF_EXITING)) { 467f2f0b00aSOleg Nesterov current->ptrace = PT_PTRACED; 468c70d9d80SEric W. Biederman ptrace_link(current, current->real_parent); 469f2f0b00aSOleg Nesterov } 470f2f0b00aSOleg Nesterov } 4714b105cbbSOleg Nesterov write_unlock_irq(&tasklist_lock); 4724b105cbbSOleg Nesterov 473f2f0b00aSOleg Nesterov return ret; 474f2f0b00aSOleg Nesterov } 475f2f0b00aSOleg Nesterov 47639c626aeSOleg Nesterov /* 47739c626aeSOleg Nesterov * Called with irqs disabled, returns true if childs should reap themselves. 47839c626aeSOleg Nesterov */ 47939c626aeSOleg Nesterov static int ignoring_children(struct sighand_struct *sigh) 48039c626aeSOleg Nesterov { 48139c626aeSOleg Nesterov int ret; 48239c626aeSOleg Nesterov spin_lock(&sigh->siglock); 48339c626aeSOleg Nesterov ret = (sigh->action[SIGCHLD-1].sa.sa_handler == SIG_IGN) || 48439c626aeSOleg Nesterov (sigh->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDWAIT); 48539c626aeSOleg Nesterov spin_unlock(&sigh->siglock); 48639c626aeSOleg Nesterov return ret; 48739c626aeSOleg Nesterov } 48839c626aeSOleg Nesterov 48939c626aeSOleg Nesterov /* 49039c626aeSOleg Nesterov * Called with tasklist_lock held for writing. 49139c626aeSOleg Nesterov * Unlink a traced task, and clean it up if it was a traced zombie. 49239c626aeSOleg Nesterov * Return true if it needs to be reaped with release_task(). 49339c626aeSOleg Nesterov * (We can't call release_task() here because we already hold tasklist_lock.) 49439c626aeSOleg Nesterov * 49539c626aeSOleg Nesterov * If it's a zombie, our attachedness prevented normal parent notification 49639c626aeSOleg Nesterov * or self-reaping. Do notification now if it would have happened earlier. 49739c626aeSOleg Nesterov * If it should reap itself, return true. 49839c626aeSOleg Nesterov * 499a7f0765eSOleg Nesterov * If it's our own child, there is no notification to do. But if our normal 500a7f0765eSOleg Nesterov * children self-reap, then this child was prevented by ptrace and we must 501a7f0765eSOleg Nesterov * reap it now, in that case we must also wake up sub-threads sleeping in 502a7f0765eSOleg Nesterov * do_wait(). 50339c626aeSOleg Nesterov */ 50439c626aeSOleg Nesterov static bool __ptrace_detach(struct task_struct *tracer, struct task_struct *p) 50539c626aeSOleg Nesterov { 5069843a1e9SOleg Nesterov bool dead; 5079843a1e9SOleg Nesterov 50839c626aeSOleg Nesterov __ptrace_unlink(p); 50939c626aeSOleg Nesterov 5109843a1e9SOleg Nesterov if (p->exit_state != EXIT_ZOMBIE) 5119843a1e9SOleg Nesterov return false; 5129843a1e9SOleg Nesterov 5139843a1e9SOleg Nesterov dead = !thread_group_leader(p); 5149843a1e9SOleg Nesterov 5159843a1e9SOleg Nesterov if (!dead && thread_group_empty(p)) { 51639c626aeSOleg Nesterov if (!same_thread_group(p->real_parent, tracer)) 5179843a1e9SOleg Nesterov dead = do_notify_parent(p, p->exit_signal); 518a7f0765eSOleg Nesterov else if (ignoring_children(tracer->sighand)) { 519a7f0765eSOleg Nesterov __wake_up_parent(p, tracer); 5209843a1e9SOleg Nesterov dead = true; 52139c626aeSOleg Nesterov } 522a7f0765eSOleg Nesterov } 52339c626aeSOleg Nesterov /* Mark it as in the process of being reaped. */ 5249843a1e9SOleg Nesterov if (dead) 52539c626aeSOleg Nesterov p->exit_state = EXIT_DEAD; 5269843a1e9SOleg Nesterov return dead; 52739c626aeSOleg Nesterov } 52839c626aeSOleg Nesterov 529e3e89cc5SLinus Torvalds static int ptrace_detach(struct task_struct *child, unsigned int data) 5301da177e4SLinus Torvalds { 5317ed20e1aSJesper Juhl if (!valid_signal(data)) 5321da177e4SLinus Torvalds return -EIO; 5331da177e4SLinus Torvalds 5341da177e4SLinus Torvalds /* Architecture-specific hardware disable .. */ 5351da177e4SLinus Torvalds ptrace_disable(child); 5361da177e4SLinus Torvalds 53795c3eb76SOleg Nesterov write_lock_irq(&tasklist_lock); 53839c626aeSOleg Nesterov /* 53964a4096cSOleg Nesterov * We rely on ptrace_freeze_traced(). It can't be killed and 54064a4096cSOleg Nesterov * untraced by another thread, it can't be a zombie. 54139c626aeSOleg Nesterov */ 54264a4096cSOleg Nesterov WARN_ON(!child->ptrace || child->exit_state); 54364a4096cSOleg Nesterov /* 54464a4096cSOleg Nesterov * tasklist_lock avoids the race with wait_task_stopped(), see 54564a4096cSOleg Nesterov * the comment in ptrace_resume(). 54664a4096cSOleg Nesterov */ 54795c3eb76SOleg Nesterov child->exit_code = data; 54864a4096cSOleg Nesterov __ptrace_detach(current, child); 5491da177e4SLinus Torvalds write_unlock_irq(&tasklist_lock); 5501da177e4SLinus Torvalds 551f701e5b7SVladimir Zapolskiy proc_ptrace_connector(child, PTRACE_DETACH); 5524576145cSOleg Nesterov 5531da177e4SLinus Torvalds return 0; 5541da177e4SLinus Torvalds } 5551da177e4SLinus Torvalds 55639c626aeSOleg Nesterov /* 557c7e49c14SOleg Nesterov * Detach all tasks we were using ptrace on. Called with tasklist held 5587c8bd232SOleg Nesterov * for writing. 55939c626aeSOleg Nesterov */ 5607c8bd232SOleg Nesterov void exit_ptrace(struct task_struct *tracer, struct list_head *dead) 56139c626aeSOleg Nesterov { 56239c626aeSOleg Nesterov struct task_struct *p, *n; 563c7e49c14SOleg Nesterov 56439c626aeSOleg Nesterov list_for_each_entry_safe(p, n, &tracer->ptraced, ptrace_entry) { 565992fb6e1SOleg Nesterov if (unlikely(p->ptrace & PT_EXITKILL)) 566079b22dcSEric W. Biederman send_sig_info(SIGKILL, SEND_SIG_PRIV, p); 567992fb6e1SOleg Nesterov 56839c626aeSOleg Nesterov if (__ptrace_detach(tracer, p)) 5697c8bd232SOleg Nesterov list_add(&p->ptrace_entry, dead); 57039c626aeSOleg Nesterov } 57139c626aeSOleg Nesterov } 57239c626aeSOleg Nesterov 5731da177e4SLinus Torvalds int ptrace_readdata(struct task_struct *tsk, unsigned long src, char __user *dst, int len) 5741da177e4SLinus Torvalds { 5751da177e4SLinus Torvalds int copied = 0; 5761da177e4SLinus Torvalds 5771da177e4SLinus Torvalds while (len > 0) { 5781da177e4SLinus Torvalds char buf[128]; 5791da177e4SLinus Torvalds int this_len, retval; 5801da177e4SLinus Torvalds 5811da177e4SLinus Torvalds this_len = (len > sizeof(buf)) ? sizeof(buf) : len; 58284d77d3fSEric W. Biederman retval = ptrace_access_vm(tsk, src, buf, this_len, FOLL_FORCE); 58384d77d3fSEric W. Biederman 5841da177e4SLinus Torvalds if (!retval) { 5851da177e4SLinus Torvalds if (copied) 5861da177e4SLinus Torvalds break; 5871da177e4SLinus Torvalds return -EIO; 5881da177e4SLinus Torvalds } 5891da177e4SLinus Torvalds if (copy_to_user(dst, buf, retval)) 5901da177e4SLinus Torvalds return -EFAULT; 5911da177e4SLinus Torvalds copied += retval; 5921da177e4SLinus Torvalds src += retval; 5931da177e4SLinus Torvalds dst += retval; 5941da177e4SLinus Torvalds len -= retval; 5951da177e4SLinus Torvalds } 5961da177e4SLinus Torvalds return copied; 5971da177e4SLinus Torvalds } 5981da177e4SLinus Torvalds 5991da177e4SLinus Torvalds int ptrace_writedata(struct task_struct *tsk, char __user *src, unsigned long dst, int len) 6001da177e4SLinus Torvalds { 6011da177e4SLinus Torvalds int copied = 0; 6021da177e4SLinus Torvalds 6031da177e4SLinus Torvalds while (len > 0) { 6041da177e4SLinus Torvalds char buf[128]; 6051da177e4SLinus Torvalds int this_len, retval; 6061da177e4SLinus Torvalds 6071da177e4SLinus Torvalds this_len = (len > sizeof(buf)) ? sizeof(buf) : len; 6081da177e4SLinus Torvalds if (copy_from_user(buf, src, this_len)) 6091da177e4SLinus Torvalds return -EFAULT; 61084d77d3fSEric W. Biederman retval = ptrace_access_vm(tsk, dst, buf, this_len, 611f307ab6dSLorenzo Stoakes FOLL_FORCE | FOLL_WRITE); 6121da177e4SLinus Torvalds if (!retval) { 6131da177e4SLinus Torvalds if (copied) 6141da177e4SLinus Torvalds break; 6151da177e4SLinus Torvalds return -EIO; 6161da177e4SLinus Torvalds } 6171da177e4SLinus Torvalds copied += retval; 6181da177e4SLinus Torvalds src += retval; 6191da177e4SLinus Torvalds dst += retval; 6201da177e4SLinus Torvalds len -= retval; 6211da177e4SLinus Torvalds } 6221da177e4SLinus Torvalds return copied; 6231da177e4SLinus Torvalds } 6241da177e4SLinus Torvalds 6254abf9869SNamhyung Kim static int ptrace_setoptions(struct task_struct *child, unsigned long data) 6261da177e4SLinus Torvalds { 62786b6c1f3SDenys Vlasenko unsigned flags; 62886b6c1f3SDenys Vlasenko 6298c5cf9e5SDenys Vlasenko if (data & ~(unsigned long)PTRACE_O_MASK) 6308c5cf9e5SDenys Vlasenko return -EINVAL; 6318c5cf9e5SDenys Vlasenko 63213c4a901STycho Andersen if (unlikely(data & PTRACE_O_SUSPEND_SECCOMP)) { 63397f2645fSMasahiro Yamada if (!IS_ENABLED(CONFIG_CHECKPOINT_RESTORE) || 63497f2645fSMasahiro Yamada !IS_ENABLED(CONFIG_SECCOMP)) 63513c4a901STycho Andersen return -EINVAL; 63613c4a901STycho Andersen 63713c4a901STycho Andersen if (!capable(CAP_SYS_ADMIN)) 63813c4a901STycho Andersen return -EPERM; 63913c4a901STycho Andersen 64013c4a901STycho Andersen if (seccomp_mode(¤t->seccomp) != SECCOMP_MODE_DISABLED || 64113c4a901STycho Andersen current->ptrace & PT_SUSPEND_SECCOMP) 64213c4a901STycho Andersen return -EPERM; 64313c4a901STycho Andersen } 64413c4a901STycho Andersen 64586b6c1f3SDenys Vlasenko /* Avoid intermediate state when all opts are cleared */ 64686b6c1f3SDenys Vlasenko flags = child->ptrace; 64786b6c1f3SDenys Vlasenko flags &= ~(PTRACE_O_MASK << PT_OPT_FLAG_SHIFT); 64886b6c1f3SDenys Vlasenko flags |= (data << PT_OPT_FLAG_SHIFT); 64986b6c1f3SDenys Vlasenko child->ptrace = flags; 6501da177e4SLinus Torvalds 6518c5cf9e5SDenys Vlasenko return 0; 6521da177e4SLinus Torvalds } 6531da177e4SLinus Torvalds 654e16b2781SRoland McGrath static int ptrace_getsiginfo(struct task_struct *child, siginfo_t *info) 6551da177e4SLinus Torvalds { 656e4961254SOleg Nesterov unsigned long flags; 6571da177e4SLinus Torvalds int error = -ESRCH; 6581da177e4SLinus Torvalds 659e4961254SOleg Nesterov if (lock_task_sighand(child, &flags)) { 6601da177e4SLinus Torvalds error = -EINVAL; 6611da177e4SLinus Torvalds if (likely(child->last_siginfo != NULL)) { 6620752d7bfSEric W. Biederman copy_siginfo(info, child->last_siginfo); 6631da177e4SLinus Torvalds error = 0; 6641da177e4SLinus Torvalds } 665e4961254SOleg Nesterov unlock_task_sighand(child, &flags); 6661da177e4SLinus Torvalds } 6671da177e4SLinus Torvalds return error; 6681da177e4SLinus Torvalds } 6691da177e4SLinus Torvalds 670e16b2781SRoland McGrath static int ptrace_setsiginfo(struct task_struct *child, const siginfo_t *info) 6711da177e4SLinus Torvalds { 672e4961254SOleg Nesterov unsigned long flags; 6731da177e4SLinus Torvalds int error = -ESRCH; 6741da177e4SLinus Torvalds 675e4961254SOleg Nesterov if (lock_task_sighand(child, &flags)) { 6761da177e4SLinus Torvalds error = -EINVAL; 6771da177e4SLinus Torvalds if (likely(child->last_siginfo != NULL)) { 6780752d7bfSEric W. Biederman copy_siginfo(child->last_siginfo, info); 6791da177e4SLinus Torvalds error = 0; 6801da177e4SLinus Torvalds } 681e4961254SOleg Nesterov unlock_task_sighand(child, &flags); 6821da177e4SLinus Torvalds } 6831da177e4SLinus Torvalds return error; 6841da177e4SLinus Torvalds } 6851da177e4SLinus Torvalds 68684c751bdSAndrey Vagin static int ptrace_peek_siginfo(struct task_struct *child, 68784c751bdSAndrey Vagin unsigned long addr, 68884c751bdSAndrey Vagin unsigned long data) 68984c751bdSAndrey Vagin { 69084c751bdSAndrey Vagin struct ptrace_peeksiginfo_args arg; 69184c751bdSAndrey Vagin struct sigpending *pending; 69284c751bdSAndrey Vagin struct sigqueue *q; 69384c751bdSAndrey Vagin int ret, i; 69484c751bdSAndrey Vagin 69584c751bdSAndrey Vagin ret = copy_from_user(&arg, (void __user *) addr, 69684c751bdSAndrey Vagin sizeof(struct ptrace_peeksiginfo_args)); 69784c751bdSAndrey Vagin if (ret) 69884c751bdSAndrey Vagin return -EFAULT; 69984c751bdSAndrey Vagin 70084c751bdSAndrey Vagin if (arg.flags & ~PTRACE_PEEKSIGINFO_SHARED) 70184c751bdSAndrey Vagin return -EINVAL; /* unknown flags */ 70284c751bdSAndrey Vagin 70384c751bdSAndrey Vagin if (arg.nr < 0) 70484c751bdSAndrey Vagin return -EINVAL; 70584c751bdSAndrey Vagin 70684c751bdSAndrey Vagin if (arg.flags & PTRACE_PEEKSIGINFO_SHARED) 70784c751bdSAndrey Vagin pending = &child->signal->shared_pending; 70884c751bdSAndrey Vagin else 70984c751bdSAndrey Vagin pending = &child->pending; 71084c751bdSAndrey Vagin 71184c751bdSAndrey Vagin for (i = 0; i < arg.nr; ) { 71284c751bdSAndrey Vagin siginfo_t info; 71384c751bdSAndrey Vagin s32 off = arg.off + i; 71484c751bdSAndrey Vagin 71584c751bdSAndrey Vagin spin_lock_irq(&child->sighand->siglock); 71684c751bdSAndrey Vagin list_for_each_entry(q, &pending->list, list) { 71784c751bdSAndrey Vagin if (!off--) { 71884c751bdSAndrey Vagin copy_siginfo(&info, &q->info); 71984c751bdSAndrey Vagin break; 72084c751bdSAndrey Vagin } 72184c751bdSAndrey Vagin } 72284c751bdSAndrey Vagin spin_unlock_irq(&child->sighand->siglock); 72384c751bdSAndrey Vagin 72484c751bdSAndrey Vagin if (off >= 0) /* beyond the end of the list */ 72584c751bdSAndrey Vagin break; 72684c751bdSAndrey Vagin 72784c751bdSAndrey Vagin #ifdef CONFIG_COMPAT 7285c465217SAndy Lutomirski if (unlikely(in_compat_syscall())) { 72984c751bdSAndrey Vagin compat_siginfo_t __user *uinfo = compat_ptr(data); 73084c751bdSAndrey Vagin 731cc731525SEric W. Biederman if (copy_siginfo_to_user32(uinfo, &info)) { 732706b23bdSMathieu Desnoyers ret = -EFAULT; 733706b23bdSMathieu Desnoyers break; 734706b23bdSMathieu Desnoyers } 735706b23bdSMathieu Desnoyers 73684c751bdSAndrey Vagin } else 73784c751bdSAndrey Vagin #endif 73884c751bdSAndrey Vagin { 73984c751bdSAndrey Vagin siginfo_t __user *uinfo = (siginfo_t __user *) data; 74084c751bdSAndrey Vagin 741cc731525SEric W. Biederman if (copy_siginfo_to_user(uinfo, &info)) { 74284c751bdSAndrey Vagin ret = -EFAULT; 74384c751bdSAndrey Vagin break; 74484c751bdSAndrey Vagin } 745706b23bdSMathieu Desnoyers } 74684c751bdSAndrey Vagin 74784c751bdSAndrey Vagin data += sizeof(siginfo_t); 74884c751bdSAndrey Vagin i++; 74984c751bdSAndrey Vagin 75084c751bdSAndrey Vagin if (signal_pending(current)) 75184c751bdSAndrey Vagin break; 75284c751bdSAndrey Vagin 75384c751bdSAndrey Vagin cond_resched(); 75484c751bdSAndrey Vagin } 75584c751bdSAndrey Vagin 75684c751bdSAndrey Vagin if (i > 0) 75784c751bdSAndrey Vagin return i; 75884c751bdSAndrey Vagin 75984c751bdSAndrey Vagin return ret; 76084c751bdSAndrey Vagin } 76136df29d7SRoland McGrath 76236df29d7SRoland McGrath #ifdef PTRACE_SINGLESTEP 76336df29d7SRoland McGrath #define is_singlestep(request) ((request) == PTRACE_SINGLESTEP) 76436df29d7SRoland McGrath #else 76536df29d7SRoland McGrath #define is_singlestep(request) 0 76636df29d7SRoland McGrath #endif 76736df29d7SRoland McGrath 7685b88abbfSRoland McGrath #ifdef PTRACE_SINGLEBLOCK 7695b88abbfSRoland McGrath #define is_singleblock(request) ((request) == PTRACE_SINGLEBLOCK) 7705b88abbfSRoland McGrath #else 7715b88abbfSRoland McGrath #define is_singleblock(request) 0 7725b88abbfSRoland McGrath #endif 7735b88abbfSRoland McGrath 77436df29d7SRoland McGrath #ifdef PTRACE_SYSEMU 77536df29d7SRoland McGrath #define is_sysemu_singlestep(request) ((request) == PTRACE_SYSEMU_SINGLESTEP) 77636df29d7SRoland McGrath #else 77736df29d7SRoland McGrath #define is_sysemu_singlestep(request) 0 77836df29d7SRoland McGrath #endif 77936df29d7SRoland McGrath 7804abf9869SNamhyung Kim static int ptrace_resume(struct task_struct *child, long request, 7814abf9869SNamhyung Kim unsigned long data) 78236df29d7SRoland McGrath { 783b72c1869SOleg Nesterov bool need_siglock; 784b72c1869SOleg Nesterov 78536df29d7SRoland McGrath if (!valid_signal(data)) 78636df29d7SRoland McGrath return -EIO; 78736df29d7SRoland McGrath 78836df29d7SRoland McGrath if (request == PTRACE_SYSCALL) 78936df29d7SRoland McGrath set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); 79036df29d7SRoland McGrath else 79136df29d7SRoland McGrath clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); 79236df29d7SRoland McGrath 79336df29d7SRoland McGrath #ifdef TIF_SYSCALL_EMU 79436df29d7SRoland McGrath if (request == PTRACE_SYSEMU || request == PTRACE_SYSEMU_SINGLESTEP) 79536df29d7SRoland McGrath set_tsk_thread_flag(child, TIF_SYSCALL_EMU); 79636df29d7SRoland McGrath else 79736df29d7SRoland McGrath clear_tsk_thread_flag(child, TIF_SYSCALL_EMU); 79836df29d7SRoland McGrath #endif 79936df29d7SRoland McGrath 8005b88abbfSRoland McGrath if (is_singleblock(request)) { 8015b88abbfSRoland McGrath if (unlikely(!arch_has_block_step())) 8025b88abbfSRoland McGrath return -EIO; 8035b88abbfSRoland McGrath user_enable_block_step(child); 8045b88abbfSRoland McGrath } else if (is_singlestep(request) || is_sysemu_singlestep(request)) { 80536df29d7SRoland McGrath if (unlikely(!arch_has_single_step())) 80636df29d7SRoland McGrath return -EIO; 80736df29d7SRoland McGrath user_enable_single_step(child); 8083a709703SRoland McGrath } else { 80936df29d7SRoland McGrath user_disable_single_step(child); 8103a709703SRoland McGrath } 81136df29d7SRoland McGrath 812b72c1869SOleg Nesterov /* 813b72c1869SOleg Nesterov * Change ->exit_code and ->state under siglock to avoid the race 814b72c1869SOleg Nesterov * with wait_task_stopped() in between; a non-zero ->exit_code will 815b72c1869SOleg Nesterov * wrongly look like another report from tracee. 816b72c1869SOleg Nesterov * 817b72c1869SOleg Nesterov * Note that we need siglock even if ->exit_code == data and/or this 818b72c1869SOleg Nesterov * status was not reported yet, the new status must not be cleared by 819b72c1869SOleg Nesterov * wait_task_stopped() after resume. 820b72c1869SOleg Nesterov * 821b72c1869SOleg Nesterov * If data == 0 we do not care if wait_task_stopped() reports the old 822b72c1869SOleg Nesterov * status and clears the code too; this can't race with the tracee, it 823b72c1869SOleg Nesterov * takes siglock after resume. 824b72c1869SOleg Nesterov */ 825b72c1869SOleg Nesterov need_siglock = data && !thread_group_empty(current); 826b72c1869SOleg Nesterov if (need_siglock) 827b72c1869SOleg Nesterov spin_lock_irq(&child->sighand->siglock); 82836df29d7SRoland McGrath child->exit_code = data; 8290666fb51SOleg Nesterov wake_up_state(child, __TASK_TRACED); 830b72c1869SOleg Nesterov if (need_siglock) 831b72c1869SOleg Nesterov spin_unlock_irq(&child->sighand->siglock); 83236df29d7SRoland McGrath 83336df29d7SRoland McGrath return 0; 83436df29d7SRoland McGrath } 83536df29d7SRoland McGrath 8362225a122SSuresh Siddha #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 8372225a122SSuresh Siddha 8382225a122SSuresh Siddha static const struct user_regset * 8392225a122SSuresh Siddha find_regset(const struct user_regset_view *view, unsigned int type) 8402225a122SSuresh Siddha { 8412225a122SSuresh Siddha const struct user_regset *regset; 8422225a122SSuresh Siddha int n; 8432225a122SSuresh Siddha 8442225a122SSuresh Siddha for (n = 0; n < view->n; ++n) { 8452225a122SSuresh Siddha regset = view->regsets + n; 8462225a122SSuresh Siddha if (regset->core_note_type == type) 8472225a122SSuresh Siddha return regset; 8482225a122SSuresh Siddha } 8492225a122SSuresh Siddha 8502225a122SSuresh Siddha return NULL; 8512225a122SSuresh Siddha } 8522225a122SSuresh Siddha 8532225a122SSuresh Siddha static int ptrace_regset(struct task_struct *task, int req, unsigned int type, 8542225a122SSuresh Siddha struct iovec *kiov) 8552225a122SSuresh Siddha { 8562225a122SSuresh Siddha const struct user_regset_view *view = task_user_regset_view(task); 8572225a122SSuresh Siddha const struct user_regset *regset = find_regset(view, type); 8582225a122SSuresh Siddha int regset_no; 8592225a122SSuresh Siddha 8602225a122SSuresh Siddha if (!regset || (kiov->iov_len % regset->size) != 0) 861c6a0dd7eSSuresh Siddha return -EINVAL; 8622225a122SSuresh Siddha 8632225a122SSuresh Siddha regset_no = regset - view->regsets; 8642225a122SSuresh Siddha kiov->iov_len = min(kiov->iov_len, 8652225a122SSuresh Siddha (__kernel_size_t) (regset->n * regset->size)); 8662225a122SSuresh Siddha 8672225a122SSuresh Siddha if (req == PTRACE_GETREGSET) 8682225a122SSuresh Siddha return copy_regset_to_user(task, view, regset_no, 0, 8692225a122SSuresh Siddha kiov->iov_len, kiov->iov_base); 8702225a122SSuresh Siddha else 8712225a122SSuresh Siddha return copy_regset_from_user(task, view, regset_no, 0, 8722225a122SSuresh Siddha kiov->iov_len, kiov->iov_base); 8732225a122SSuresh Siddha } 8742225a122SSuresh Siddha 875e8440c14SJosh Stone /* 876e8440c14SJosh Stone * This is declared in linux/regset.h and defined in machine-dependent 877e8440c14SJosh Stone * code. We put the export here, near the primary machine-neutral use, 878e8440c14SJosh Stone * to ensure no machine forgets it. 879e8440c14SJosh Stone */ 880e8440c14SJosh Stone EXPORT_SYMBOL_GPL(task_user_regset_view); 8812225a122SSuresh Siddha #endif 8822225a122SSuresh Siddha 8831da177e4SLinus Torvalds int ptrace_request(struct task_struct *child, long request, 8844abf9869SNamhyung Kim unsigned long addr, unsigned long data) 8851da177e4SLinus Torvalds { 886fca26f26STejun Heo bool seized = child->ptrace & PT_SEIZED; 8871da177e4SLinus Torvalds int ret = -EIO; 888544b2c91STejun Heo siginfo_t siginfo, *si; 8899fed81dcSNamhyung Kim void __user *datavp = (void __user *) data; 8909fed81dcSNamhyung Kim unsigned long __user *datalp = datavp; 891fca26f26STejun Heo unsigned long flags; 8921da177e4SLinus Torvalds 8931da177e4SLinus Torvalds switch (request) { 89416c3e389SRoland McGrath case PTRACE_PEEKTEXT: 89516c3e389SRoland McGrath case PTRACE_PEEKDATA: 89616c3e389SRoland McGrath return generic_ptrace_peekdata(child, addr, data); 89716c3e389SRoland McGrath case PTRACE_POKETEXT: 89816c3e389SRoland McGrath case PTRACE_POKEDATA: 89916c3e389SRoland McGrath return generic_ptrace_pokedata(child, addr, data); 90016c3e389SRoland McGrath 9011da177e4SLinus Torvalds #ifdef PTRACE_OLDSETOPTIONS 9021da177e4SLinus Torvalds case PTRACE_OLDSETOPTIONS: 9031da177e4SLinus Torvalds #endif 9041da177e4SLinus Torvalds case PTRACE_SETOPTIONS: 9051da177e4SLinus Torvalds ret = ptrace_setoptions(child, data); 9061da177e4SLinus Torvalds break; 9071da177e4SLinus Torvalds case PTRACE_GETEVENTMSG: 9089fed81dcSNamhyung Kim ret = put_user(child->ptrace_message, datalp); 9091da177e4SLinus Torvalds break; 910e16b2781SRoland McGrath 91184c751bdSAndrey Vagin case PTRACE_PEEKSIGINFO: 91284c751bdSAndrey Vagin ret = ptrace_peek_siginfo(child, addr, data); 91384c751bdSAndrey Vagin break; 91484c751bdSAndrey Vagin 9151da177e4SLinus Torvalds case PTRACE_GETSIGINFO: 916e16b2781SRoland McGrath ret = ptrace_getsiginfo(child, &siginfo); 917e16b2781SRoland McGrath if (!ret) 9189fed81dcSNamhyung Kim ret = copy_siginfo_to_user(datavp, &siginfo); 9191da177e4SLinus Torvalds break; 920e16b2781SRoland McGrath 9211da177e4SLinus Torvalds case PTRACE_SETSIGINFO: 9224cd2e0e7SEric W. Biederman ret = copy_siginfo_from_user(&siginfo, datavp); 9234cd2e0e7SEric W. Biederman if (!ret) 924e16b2781SRoland McGrath ret = ptrace_setsiginfo(child, &siginfo); 9251da177e4SLinus Torvalds break; 926e16b2781SRoland McGrath 92729000caeSAndrey Vagin case PTRACE_GETSIGMASK: 92829000caeSAndrey Vagin if (addr != sizeof(sigset_t)) { 92929000caeSAndrey Vagin ret = -EINVAL; 93029000caeSAndrey Vagin break; 93129000caeSAndrey Vagin } 93229000caeSAndrey Vagin 93329000caeSAndrey Vagin if (copy_to_user(datavp, &child->blocked, sizeof(sigset_t))) 93429000caeSAndrey Vagin ret = -EFAULT; 93529000caeSAndrey Vagin else 93629000caeSAndrey Vagin ret = 0; 93729000caeSAndrey Vagin 93829000caeSAndrey Vagin break; 93929000caeSAndrey Vagin 94029000caeSAndrey Vagin case PTRACE_SETSIGMASK: { 94129000caeSAndrey Vagin sigset_t new_set; 94229000caeSAndrey Vagin 94329000caeSAndrey Vagin if (addr != sizeof(sigset_t)) { 94429000caeSAndrey Vagin ret = -EINVAL; 94529000caeSAndrey Vagin break; 94629000caeSAndrey Vagin } 94729000caeSAndrey Vagin 94829000caeSAndrey Vagin if (copy_from_user(&new_set, datavp, sizeof(sigset_t))) { 94929000caeSAndrey Vagin ret = -EFAULT; 95029000caeSAndrey Vagin break; 95129000caeSAndrey Vagin } 95229000caeSAndrey Vagin 95329000caeSAndrey Vagin sigdelsetmask(&new_set, sigmask(SIGKILL)|sigmask(SIGSTOP)); 95429000caeSAndrey Vagin 95529000caeSAndrey Vagin /* 95629000caeSAndrey Vagin * Every thread does recalc_sigpending() after resume, so 95729000caeSAndrey Vagin * retarget_shared_pending() and recalc_sigpending() are not 95829000caeSAndrey Vagin * called here. 95929000caeSAndrey Vagin */ 96029000caeSAndrey Vagin spin_lock_irq(&child->sighand->siglock); 96129000caeSAndrey Vagin child->blocked = new_set; 96229000caeSAndrey Vagin spin_unlock_irq(&child->sighand->siglock); 96329000caeSAndrey Vagin 96429000caeSAndrey Vagin ret = 0; 96529000caeSAndrey Vagin break; 96629000caeSAndrey Vagin } 96729000caeSAndrey Vagin 968fca26f26STejun Heo case PTRACE_INTERRUPT: 969fca26f26STejun Heo /* 970fca26f26STejun Heo * Stop tracee without any side-effect on signal or job 971fca26f26STejun Heo * control. At least one trap is guaranteed to happen 972fca26f26STejun Heo * after this request. If @child is already trapped, the 973fca26f26STejun Heo * current trap is not disturbed and another trap will 974fca26f26STejun Heo * happen after the current trap is ended with PTRACE_CONT. 975fca26f26STejun Heo * 976fca26f26STejun Heo * The actual trap might not be PTRACE_EVENT_STOP trap but 977fca26f26STejun Heo * the pending condition is cleared regardless. 978fca26f26STejun Heo */ 979fca26f26STejun Heo if (unlikely(!seized || !lock_task_sighand(child, &flags))) 980fca26f26STejun Heo break; 981fca26f26STejun Heo 982544b2c91STejun Heo /* 983544b2c91STejun Heo * INTERRUPT doesn't disturb existing trap sans one 984544b2c91STejun Heo * exception. If ptracer issued LISTEN for the current 985544b2c91STejun Heo * STOP, this INTERRUPT should clear LISTEN and re-trap 986544b2c91STejun Heo * tracee into STOP. 987544b2c91STejun Heo */ 988fca26f26STejun Heo if (likely(task_set_jobctl_pending(child, JOBCTL_TRAP_STOP))) 989910ffdb1SOleg Nesterov ptrace_signal_wake_up(child, child->jobctl & JOBCTL_LISTENING); 990544b2c91STejun Heo 991544b2c91STejun Heo unlock_task_sighand(child, &flags); 992544b2c91STejun Heo ret = 0; 993544b2c91STejun Heo break; 994544b2c91STejun Heo 995544b2c91STejun Heo case PTRACE_LISTEN: 996544b2c91STejun Heo /* 997544b2c91STejun Heo * Listen for events. Tracee must be in STOP. It's not 998544b2c91STejun Heo * resumed per-se but is not considered to be in TRACED by 999544b2c91STejun Heo * wait(2) or ptrace(2). If an async event (e.g. group 1000544b2c91STejun Heo * stop state change) happens, tracee will enter STOP trap 1001544b2c91STejun Heo * again. Alternatively, ptracer can issue INTERRUPT to 1002544b2c91STejun Heo * finish listening and re-trap tracee into STOP. 1003544b2c91STejun Heo */ 1004544b2c91STejun Heo if (unlikely(!seized || !lock_task_sighand(child, &flags))) 1005544b2c91STejun Heo break; 1006544b2c91STejun Heo 1007544b2c91STejun Heo si = child->last_siginfo; 1008f9d81f61SOleg Nesterov if (likely(si && (si->si_code >> 8) == PTRACE_EVENT_STOP)) { 1009544b2c91STejun Heo child->jobctl |= JOBCTL_LISTENING; 1010544b2c91STejun Heo /* 1011f9d81f61SOleg Nesterov * If NOTIFY is set, it means event happened between 1012f9d81f61SOleg Nesterov * start of this trap and now. Trigger re-trap. 1013544b2c91STejun Heo */ 1014544b2c91STejun Heo if (child->jobctl & JOBCTL_TRAP_NOTIFY) 1015910ffdb1SOleg Nesterov ptrace_signal_wake_up(child, true); 1016fca26f26STejun Heo ret = 0; 1017f9d81f61SOleg Nesterov } 1018f9d81f61SOleg Nesterov unlock_task_sighand(child, &flags); 1019fca26f26STejun Heo break; 1020fca26f26STejun Heo 10211bcf5482SAlexey Dobriyan case PTRACE_DETACH: /* detach a process that was attached. */ 10221bcf5482SAlexey Dobriyan ret = ptrace_detach(child, data); 10231bcf5482SAlexey Dobriyan break; 102436df29d7SRoland McGrath 10259c1a1259SMike Frysinger #ifdef CONFIG_BINFMT_ELF_FDPIC 10269c1a1259SMike Frysinger case PTRACE_GETFDPIC: { 1027e0129ef9SOleg Nesterov struct mm_struct *mm = get_task_mm(child); 10289c1a1259SMike Frysinger unsigned long tmp = 0; 10299c1a1259SMike Frysinger 1030e0129ef9SOleg Nesterov ret = -ESRCH; 1031e0129ef9SOleg Nesterov if (!mm) 1032e0129ef9SOleg Nesterov break; 1033e0129ef9SOleg Nesterov 10349c1a1259SMike Frysinger switch (addr) { 10359c1a1259SMike Frysinger case PTRACE_GETFDPIC_EXEC: 1036e0129ef9SOleg Nesterov tmp = mm->context.exec_fdpic_loadmap; 10379c1a1259SMike Frysinger break; 10389c1a1259SMike Frysinger case PTRACE_GETFDPIC_INTERP: 1039e0129ef9SOleg Nesterov tmp = mm->context.interp_fdpic_loadmap; 10409c1a1259SMike Frysinger break; 10419c1a1259SMike Frysinger default: 10429c1a1259SMike Frysinger break; 10439c1a1259SMike Frysinger } 1044e0129ef9SOleg Nesterov mmput(mm); 10459c1a1259SMike Frysinger 10469fed81dcSNamhyung Kim ret = put_user(tmp, datalp); 10479c1a1259SMike Frysinger break; 10489c1a1259SMike Frysinger } 10499c1a1259SMike Frysinger #endif 10509c1a1259SMike Frysinger 105136df29d7SRoland McGrath #ifdef PTRACE_SINGLESTEP 105236df29d7SRoland McGrath case PTRACE_SINGLESTEP: 105336df29d7SRoland McGrath #endif 10545b88abbfSRoland McGrath #ifdef PTRACE_SINGLEBLOCK 10555b88abbfSRoland McGrath case PTRACE_SINGLEBLOCK: 10565b88abbfSRoland McGrath #endif 105736df29d7SRoland McGrath #ifdef PTRACE_SYSEMU 105836df29d7SRoland McGrath case PTRACE_SYSEMU: 105936df29d7SRoland McGrath case PTRACE_SYSEMU_SINGLESTEP: 106036df29d7SRoland McGrath #endif 106136df29d7SRoland McGrath case PTRACE_SYSCALL: 106236df29d7SRoland McGrath case PTRACE_CONT: 106336df29d7SRoland McGrath return ptrace_resume(child, request, data); 106436df29d7SRoland McGrath 106536df29d7SRoland McGrath case PTRACE_KILL: 106636df29d7SRoland McGrath if (child->exit_state) /* already dead */ 106736df29d7SRoland McGrath return 0; 106836df29d7SRoland McGrath return ptrace_resume(child, request, SIGKILL); 106936df29d7SRoland McGrath 10702225a122SSuresh Siddha #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 10712225a122SSuresh Siddha case PTRACE_GETREGSET: 107229000caeSAndrey Vagin case PTRACE_SETREGSET: { 10732225a122SSuresh Siddha struct iovec kiov; 10749fed81dcSNamhyung Kim struct iovec __user *uiov = datavp; 10752225a122SSuresh Siddha 10762225a122SSuresh Siddha if (!access_ok(VERIFY_WRITE, uiov, sizeof(*uiov))) 10772225a122SSuresh Siddha return -EFAULT; 10782225a122SSuresh Siddha 10792225a122SSuresh Siddha if (__get_user(kiov.iov_base, &uiov->iov_base) || 10802225a122SSuresh Siddha __get_user(kiov.iov_len, &uiov->iov_len)) 10812225a122SSuresh Siddha return -EFAULT; 10822225a122SSuresh Siddha 10832225a122SSuresh Siddha ret = ptrace_regset(child, request, addr, &kiov); 10842225a122SSuresh Siddha if (!ret) 10852225a122SSuresh Siddha ret = __put_user(kiov.iov_len, &uiov->iov_len); 10862225a122SSuresh Siddha break; 10872225a122SSuresh Siddha } 10882225a122SSuresh Siddha #endif 1089f8e529edSTycho Andersen 1090f8e529edSTycho Andersen case PTRACE_SECCOMP_GET_FILTER: 1091f8e529edSTycho Andersen ret = seccomp_get_filter(child, addr, datavp); 1092f8e529edSTycho Andersen break; 1093f8e529edSTycho Andersen 109426500475STycho Andersen case PTRACE_SECCOMP_GET_METADATA: 109526500475STycho Andersen ret = seccomp_get_metadata(child, addr, datavp); 109626500475STycho Andersen break; 109726500475STycho Andersen 10981da177e4SLinus Torvalds default: 10991da177e4SLinus Torvalds break; 11001da177e4SLinus Torvalds } 11011da177e4SLinus Torvalds 11021da177e4SLinus Torvalds return ret; 11031da177e4SLinus Torvalds } 1104481bed45SChristoph Hellwig 11050ac15559SChristoph Hellwig #ifndef arch_ptrace_attach 11060ac15559SChristoph Hellwig #define arch_ptrace_attach(child) do { } while (0) 11070ac15559SChristoph Hellwig #endif 11080ac15559SChristoph Hellwig 11094abf9869SNamhyung Kim SYSCALL_DEFINE4(ptrace, long, request, long, pid, unsigned long, addr, 11104abf9869SNamhyung Kim unsigned long, data) 1111481bed45SChristoph Hellwig { 1112481bed45SChristoph Hellwig struct task_struct *child; 1113481bed45SChristoph Hellwig long ret; 1114481bed45SChristoph Hellwig 11156b9c7ed8SChristoph Hellwig if (request == PTRACE_TRACEME) { 11166b9c7ed8SChristoph Hellwig ret = ptrace_traceme(); 11176ea6dd93SHaavard Skinnemoen if (!ret) 11186ea6dd93SHaavard Skinnemoen arch_ptrace_attach(current); 1119481bed45SChristoph Hellwig goto out; 11206b9c7ed8SChristoph Hellwig } 11216b9c7ed8SChristoph Hellwig 11222ee08260SMike Rapoport child = find_get_task_by_vpid(pid); 11232ee08260SMike Rapoport if (!child) { 11242ee08260SMike Rapoport ret = -ESRCH; 11256b9c7ed8SChristoph Hellwig goto out; 11266b9c7ed8SChristoph Hellwig } 1127481bed45SChristoph Hellwig 11283544d72aSTejun Heo if (request == PTRACE_ATTACH || request == PTRACE_SEIZE) { 1129aa9147c9SDenys Vlasenko ret = ptrace_attach(child, request, addr, data); 11300ac15559SChristoph Hellwig /* 11310ac15559SChristoph Hellwig * Some architectures need to do book-keeping after 11320ac15559SChristoph Hellwig * a ptrace attach. 11330ac15559SChristoph Hellwig */ 11340ac15559SChristoph Hellwig if (!ret) 11350ac15559SChristoph Hellwig arch_ptrace_attach(child); 1136005f18dfSChristoph Hellwig goto out_put_task_struct; 1137481bed45SChristoph Hellwig } 1138481bed45SChristoph Hellwig 1139fca26f26STejun Heo ret = ptrace_check_attach(child, request == PTRACE_KILL || 1140fca26f26STejun Heo request == PTRACE_INTERRUPT); 1141481bed45SChristoph Hellwig if (ret < 0) 1142481bed45SChristoph Hellwig goto out_put_task_struct; 1143481bed45SChristoph Hellwig 1144481bed45SChristoph Hellwig ret = arch_ptrace(child, request, addr, data); 11459899d11fSOleg Nesterov if (ret || request != PTRACE_DETACH) 11469899d11fSOleg Nesterov ptrace_unfreeze_traced(child); 1147481bed45SChristoph Hellwig 1148481bed45SChristoph Hellwig out_put_task_struct: 1149481bed45SChristoph Hellwig put_task_struct(child); 1150481bed45SChristoph Hellwig out: 1151481bed45SChristoph Hellwig return ret; 1152481bed45SChristoph Hellwig } 115376647323SAlexey Dobriyan 11544abf9869SNamhyung Kim int generic_ptrace_peekdata(struct task_struct *tsk, unsigned long addr, 11554abf9869SNamhyung Kim unsigned long data) 115676647323SAlexey Dobriyan { 115776647323SAlexey Dobriyan unsigned long tmp; 115876647323SAlexey Dobriyan int copied; 115976647323SAlexey Dobriyan 116084d77d3fSEric W. Biederman copied = ptrace_access_vm(tsk, addr, &tmp, sizeof(tmp), FOLL_FORCE); 116176647323SAlexey Dobriyan if (copied != sizeof(tmp)) 116276647323SAlexey Dobriyan return -EIO; 116376647323SAlexey Dobriyan return put_user(tmp, (unsigned long __user *)data); 116476647323SAlexey Dobriyan } 1165f284ce72SAlexey Dobriyan 11664abf9869SNamhyung Kim int generic_ptrace_pokedata(struct task_struct *tsk, unsigned long addr, 11674abf9869SNamhyung Kim unsigned long data) 1168f284ce72SAlexey Dobriyan { 1169f284ce72SAlexey Dobriyan int copied; 1170f284ce72SAlexey Dobriyan 117184d77d3fSEric W. Biederman copied = ptrace_access_vm(tsk, addr, &data, sizeof(data), 1172f307ab6dSLorenzo Stoakes FOLL_FORCE | FOLL_WRITE); 1173f284ce72SAlexey Dobriyan return (copied == sizeof(data)) ? 0 : -EIO; 1174f284ce72SAlexey Dobriyan } 1175032d82d9SRoland McGrath 117696b8936aSChristoph Hellwig #if defined CONFIG_COMPAT 1177032d82d9SRoland McGrath 1178032d82d9SRoland McGrath int compat_ptrace_request(struct task_struct *child, compat_long_t request, 1179032d82d9SRoland McGrath compat_ulong_t addr, compat_ulong_t data) 1180032d82d9SRoland McGrath { 1181032d82d9SRoland McGrath compat_ulong_t __user *datap = compat_ptr(data); 1182032d82d9SRoland McGrath compat_ulong_t word; 1183e16b2781SRoland McGrath siginfo_t siginfo; 1184032d82d9SRoland McGrath int ret; 1185032d82d9SRoland McGrath 1186032d82d9SRoland McGrath switch (request) { 1187032d82d9SRoland McGrath case PTRACE_PEEKTEXT: 1188032d82d9SRoland McGrath case PTRACE_PEEKDATA: 118984d77d3fSEric W. Biederman ret = ptrace_access_vm(child, addr, &word, sizeof(word), 1190f307ab6dSLorenzo Stoakes FOLL_FORCE); 1191032d82d9SRoland McGrath if (ret != sizeof(word)) 1192032d82d9SRoland McGrath ret = -EIO; 1193032d82d9SRoland McGrath else 1194032d82d9SRoland McGrath ret = put_user(word, datap); 1195032d82d9SRoland McGrath break; 1196032d82d9SRoland McGrath 1197032d82d9SRoland McGrath case PTRACE_POKETEXT: 1198032d82d9SRoland McGrath case PTRACE_POKEDATA: 119984d77d3fSEric W. Biederman ret = ptrace_access_vm(child, addr, &data, sizeof(data), 1200f307ab6dSLorenzo Stoakes FOLL_FORCE | FOLL_WRITE); 1201032d82d9SRoland McGrath ret = (ret != sizeof(data) ? -EIO : 0); 1202032d82d9SRoland McGrath break; 1203032d82d9SRoland McGrath 1204032d82d9SRoland McGrath case PTRACE_GETEVENTMSG: 1205032d82d9SRoland McGrath ret = put_user((compat_ulong_t) child->ptrace_message, datap); 1206032d82d9SRoland McGrath break; 1207032d82d9SRoland McGrath 1208e16b2781SRoland McGrath case PTRACE_GETSIGINFO: 1209e16b2781SRoland McGrath ret = ptrace_getsiginfo(child, &siginfo); 1210e16b2781SRoland McGrath if (!ret) 1211e16b2781SRoland McGrath ret = copy_siginfo_to_user32( 1212e16b2781SRoland McGrath (struct compat_siginfo __user *) datap, 1213e16b2781SRoland McGrath &siginfo); 1214e16b2781SRoland McGrath break; 1215e16b2781SRoland McGrath 1216e16b2781SRoland McGrath case PTRACE_SETSIGINFO: 12174cd2e0e7SEric W. Biederman ret = copy_siginfo_from_user32( 12184cd2e0e7SEric W. Biederman &siginfo, (struct compat_siginfo __user *) datap); 12194cd2e0e7SEric W. Biederman if (!ret) 1220e16b2781SRoland McGrath ret = ptrace_setsiginfo(child, &siginfo); 1221e16b2781SRoland McGrath break; 12222225a122SSuresh Siddha #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 12232225a122SSuresh Siddha case PTRACE_GETREGSET: 12242225a122SSuresh Siddha case PTRACE_SETREGSET: 12252225a122SSuresh Siddha { 12262225a122SSuresh Siddha struct iovec kiov; 12272225a122SSuresh Siddha struct compat_iovec __user *uiov = 12282225a122SSuresh Siddha (struct compat_iovec __user *) datap; 12292225a122SSuresh Siddha compat_uptr_t ptr; 12302225a122SSuresh Siddha compat_size_t len; 12312225a122SSuresh Siddha 12322225a122SSuresh Siddha if (!access_ok(VERIFY_WRITE, uiov, sizeof(*uiov))) 12332225a122SSuresh Siddha return -EFAULT; 12342225a122SSuresh Siddha 12352225a122SSuresh Siddha if (__get_user(ptr, &uiov->iov_base) || 12362225a122SSuresh Siddha __get_user(len, &uiov->iov_len)) 12372225a122SSuresh Siddha return -EFAULT; 12382225a122SSuresh Siddha 12392225a122SSuresh Siddha kiov.iov_base = compat_ptr(ptr); 12402225a122SSuresh Siddha kiov.iov_len = len; 12412225a122SSuresh Siddha 12422225a122SSuresh Siddha ret = ptrace_regset(child, request, addr, &kiov); 12432225a122SSuresh Siddha if (!ret) 12442225a122SSuresh Siddha ret = __put_user(kiov.iov_len, &uiov->iov_len); 12452225a122SSuresh Siddha break; 12462225a122SSuresh Siddha } 12472225a122SSuresh Siddha #endif 1248e16b2781SRoland McGrath 1249032d82d9SRoland McGrath default: 1250032d82d9SRoland McGrath ret = ptrace_request(child, request, addr, data); 1251032d82d9SRoland McGrath } 1252032d82d9SRoland McGrath 1253032d82d9SRoland McGrath return ret; 1254032d82d9SRoland McGrath } 1255c269f196SRoland McGrath 125662a6fa97SHeiko Carstens COMPAT_SYSCALL_DEFINE4(ptrace, compat_long_t, request, compat_long_t, pid, 125762a6fa97SHeiko Carstens compat_long_t, addr, compat_long_t, data) 1258c269f196SRoland McGrath { 1259c269f196SRoland McGrath struct task_struct *child; 1260c269f196SRoland McGrath long ret; 1261c269f196SRoland McGrath 1262c269f196SRoland McGrath if (request == PTRACE_TRACEME) { 1263c269f196SRoland McGrath ret = ptrace_traceme(); 1264c269f196SRoland McGrath goto out; 1265c269f196SRoland McGrath } 1266c269f196SRoland McGrath 12672ee08260SMike Rapoport child = find_get_task_by_vpid(pid); 12682ee08260SMike Rapoport if (!child) { 12692ee08260SMike Rapoport ret = -ESRCH; 1270c269f196SRoland McGrath goto out; 1271c269f196SRoland McGrath } 1272c269f196SRoland McGrath 12733544d72aSTejun Heo if (request == PTRACE_ATTACH || request == PTRACE_SEIZE) { 1274aa9147c9SDenys Vlasenko ret = ptrace_attach(child, request, addr, data); 1275c269f196SRoland McGrath /* 1276c269f196SRoland McGrath * Some architectures need to do book-keeping after 1277c269f196SRoland McGrath * a ptrace attach. 1278c269f196SRoland McGrath */ 1279c269f196SRoland McGrath if (!ret) 1280c269f196SRoland McGrath arch_ptrace_attach(child); 1281c269f196SRoland McGrath goto out_put_task_struct; 1282c269f196SRoland McGrath } 1283c269f196SRoland McGrath 1284fca26f26STejun Heo ret = ptrace_check_attach(child, request == PTRACE_KILL || 1285fca26f26STejun Heo request == PTRACE_INTERRUPT); 12869899d11fSOleg Nesterov if (!ret) { 1287c269f196SRoland McGrath ret = compat_arch_ptrace(child, request, addr, data); 12889899d11fSOleg Nesterov if (ret || request != PTRACE_DETACH) 12899899d11fSOleg Nesterov ptrace_unfreeze_traced(child); 12909899d11fSOleg Nesterov } 1291c269f196SRoland McGrath 1292c269f196SRoland McGrath out_put_task_struct: 1293c269f196SRoland McGrath put_task_struct(child); 1294c269f196SRoland McGrath out: 1295c269f196SRoland McGrath return ret; 1296c269f196SRoland McGrath } 129796b8936aSChristoph Hellwig #endif /* CONFIG_COMPAT */ 1298