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Release 4.12 include/linux/ptrace.h

Directory: include/linux
#ifndef _LINUX_PTRACE_H

#define _LINUX_PTRACE_H

#include <linux/compiler.h>		/* For unlikely.  */
#include <linux/sched.h>		/* For struct task_struct.  */
#include <linux/sched/signal.h>		/* For send_sig(), same_thread_group(), etc. */
#include <linux/err.h>			/* for IS_ERR_VALUE */
#include <linux/bug.h>			/* For BUG_ON.  */
#include <linux/pid_namespace.h>	/* For task_active_pid_ns.  */
#include <uapi/linux/ptrace.h>

extern int ptrace_access_vm(struct task_struct *tsk, unsigned long addr,
			    void *buf, int len, unsigned int gup_flags);

/*
 * Ptrace flags
 *
 * The owner ship rules for task->ptrace which holds the ptrace
 * flags is simple.  When a task is running it owns it's task->ptrace
 * flags.  When the a task is stopped the ptracer owns task->ptrace.
 */


#define PT_SEIZED	0x00010000	
/* SEIZE used, enable new behavior */

#define PT_PTRACED	0x00000001

#define PT_DTRACE	0x00000002	
/* delayed trace (used on m68k, i386) */


#define PT_OPT_FLAG_SHIFT	3
/* PT_TRACE_* event enable flags */

#define PT_EVENT_FLAG(event)	(1 << (PT_OPT_FLAG_SHIFT + (event)))

#define PT_TRACESYSGOOD		PT_EVENT_FLAG(0)

#define PT_TRACE_FORK		PT_EVENT_FLAG(PTRACE_EVENT_FORK)

#define PT_TRACE_VFORK		PT_EVENT_FLAG(PTRACE_EVENT_VFORK)

#define PT_TRACE_CLONE		PT_EVENT_FLAG(PTRACE_EVENT_CLONE)

#define PT_TRACE_EXEC		PT_EVENT_FLAG(PTRACE_EVENT_EXEC)

#define PT_TRACE_VFORK_DONE	PT_EVENT_FLAG(PTRACE_EVENT_VFORK_DONE)

#define PT_TRACE_EXIT		PT_EVENT_FLAG(PTRACE_EVENT_EXIT)

#define PT_TRACE_SECCOMP	PT_EVENT_FLAG(PTRACE_EVENT_SECCOMP)


#define PT_EXITKILL		(PTRACE_O_EXITKILL << PT_OPT_FLAG_SHIFT)

#define PT_SUSPEND_SECCOMP	(PTRACE_O_SUSPEND_SECCOMP << PT_OPT_FLAG_SHIFT)

/* single stepping state bits (used on ARM and PA-RISC) */

#define PT_SINGLESTEP_BIT	31

#define PT_SINGLESTEP		(1<<PT_SINGLESTEP_BIT)

#define PT_BLOCKSTEP_BIT	30

#define PT_BLOCKSTEP		(1<<PT_BLOCKSTEP_BIT)

extern long arch_ptrace(struct task_struct *child, long request,
			unsigned long addr, unsigned long data);
extern int ptrace_readdata(struct task_struct *tsk, unsigned long src, char __user *dst, int len);
extern int ptrace_writedata(struct task_struct *tsk, char __user *src, unsigned long dst, int len);
extern void ptrace_disable(struct task_struct *);
extern int ptrace_request(struct task_struct *child, long request,
			  unsigned long addr, unsigned long data);
extern void ptrace_notify(int exit_code);
extern void __ptrace_link(struct task_struct *child,
			  struct task_struct *new_parent,
			  const struct cred *ptracer_cred);
extern void __ptrace_unlink(struct task_struct *child);
extern void exit_ptrace(struct task_struct *tracer, struct list_head *dead);

#define PTRACE_MODE_READ	0x01

#define PTRACE_MODE_ATTACH	0x02

#define PTRACE_MODE_NOAUDIT	0x04

#define PTRACE_MODE_FSCREDS 0x08

#define PTRACE_MODE_REALCREDS 0x10

/* shorthands for READ/ATTACH and FSCREDS/REALCREDS combinations */

#define PTRACE_MODE_READ_FSCREDS (PTRACE_MODE_READ | PTRACE_MODE_FSCREDS)

#define PTRACE_MODE_READ_REALCREDS (PTRACE_MODE_READ | PTRACE_MODE_REALCREDS)

#define PTRACE_MODE_ATTACH_FSCREDS (PTRACE_MODE_ATTACH | PTRACE_MODE_FSCREDS)

#define PTRACE_MODE_ATTACH_REALCREDS (PTRACE_MODE_ATTACH | PTRACE_MODE_REALCREDS)

/**
 * ptrace_may_access - check whether the caller is permitted to access
 * a target task.
 * @task: target task
 * @mode: selects type of access and caller credentials
 *
 * Returns true on success, false on denial.
 *
 * One of the flags PTRACE_MODE_FSCREDS and PTRACE_MODE_REALCREDS must
 * be set in @mode to specify whether the access was requested through
 * a filesystem syscall (should use effective capabilities and fsuid
 * of the caller) or through an explicit syscall such as
 * process_vm_writev or ptrace (and should use the real credentials).
 */
extern bool ptrace_may_access(struct task_struct *task, unsigned int mode);


static inline int ptrace_reparented(struct task_struct *child) { return !same_thread_group(child->real_parent, child->parent); }

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Oleg Nesterov25100.00%2100.00%
Total25100.00%2100.00%


static inline void ptrace_unlink(struct task_struct *child) { if (unlikely(child->ptrace)) __ptrace_unlink(child); }

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Ingo Molnar26100.00%1100.00%
Total26100.00%1100.00%

int generic_ptrace_peekdata(struct task_struct *tsk, unsigned long addr, unsigned long data); int generic_ptrace_pokedata(struct task_struct *tsk, unsigned long addr, unsigned long data); /** * ptrace_parent - return the task that is tracing the given task * @task: task to consider * * Returns %NULL if no one is tracing @task, or the &struct task_struct * pointer to its tracer. * * Must called under rcu_read_lock(). The pointer returned might be kept * live only by RCU. During exec, this may be called with task_lock() held * on @task, still held from when check_unsafe_exec() was called. */
static inline struct task_struct *ptrace_parent(struct task_struct *task) { if (unlikely(task->ptrace)) return rcu_dereference(task->parent); return NULL; }

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Tejun Heo34100.00%1100.00%
Total34100.00%1100.00%

/** * ptrace_event_enabled - test whether a ptrace event is enabled * @task: ptracee of interest * @event: %PTRACE_EVENT_* to test * * Test whether @event is enabled for ptracee @task. * * Returns %true if @event is enabled, %false otherwise. */
static inline bool ptrace_event_enabled(struct task_struct *task, int event) { return task->ptrace & PT_EVENT_FLAG(event); }

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Tejun Heo25100.00%1100.00%
Total25100.00%1100.00%

/** * ptrace_event - possibly stop for a ptrace event notification * @event: %PTRACE_EVENT_* value to report * @message: value for %PTRACE_GETEVENTMSG to return * * Check whether @event is enabled and, if so, report @event and @message * to the ptrace parent. * * Called without locks. */
static inline void ptrace_event(int event, unsigned long message) { if (unlikely(ptrace_event_enabled(current, event))) { current->ptrace_message = message; ptrace_notify((event << 8) | SIGTRAP); } else if (event == PTRACE_EVENT_EXEC) { /* legacy EXEC report via SIGTRAP */ if ((current->ptrace & (PT_PTRACED|PT_SEIZED)) == PT_PTRACED) send_sig(SIGTRAP, current, 0); } }

Contributors

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Roland McGrath3645.00%125.00%
Tejun Heo2936.25%250.00%
Oleg Nesterov1518.75%125.00%
Total80100.00%4100.00%

/** * ptrace_event_pid - possibly stop for a ptrace event notification * @event: %PTRACE_EVENT_* value to report * @pid: process identifier for %PTRACE_GETEVENTMSG to return * * Check whether @event is enabled and, if so, report @event and @pid * to the ptrace parent. @pid is reported as the pid_t seen from the * the ptrace parent's pid namespace. * * Called without locks. */
static inline void ptrace_event_pid(int event, struct pid *pid) { /* * FIXME: There's a potential race if a ptracer in a different pid * namespace than parent attaches between computing message below and * when we acquire tasklist_lock in ptrace_stop(). If this happens, * the ptracer will get a bogus pid from PTRACE_GETEVENTMSG. */ unsigned long message = 0; struct pid_namespace *ns; rcu_read_lock(); ns = task_active_pid_ns(rcu_dereference(current->parent)); if (ns) message = pid_nr_ns(pid, ns); rcu_read_unlock(); ptrace_event(event, message); }

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Matthew Dempsky65100.00%1100.00%
Total65100.00%1100.00%

/** * ptrace_init_task - initialize ptrace state for a new child * @child: new child task * @ptrace: true if child should be ptrace'd by parent's tracer * * This is called immediately after adding @child to its parent's children * list. @ptrace is false in the normal case, and true to ptrace @child. * * Called with current's siglock and write_lock_irq(&tasklist_lock) held. */
static inline void ptrace_init_task(struct task_struct *child, bool ptrace) { INIT_LIST_HEAD(&child->ptrace_entry); INIT_LIST_HEAD(&child->ptraced); child->jobctl = 0; child->ptrace = 0; child->parent = child->real_parent; if (unlikely(ptrace) && current->ptrace) { child->ptrace = current->ptrace; __ptrace_link(child, current->parent, current->ptracer_cred); if (child->ptrace & PT_SEIZED) task_set_jobctl_pending(child, JOBCTL_TRAP_STOP); else sigaddset(&child->pending.signal, SIGSTOP); set_tsk_thread_flag(child, TIF_SIGPENDING); } else child->ptracer_cred = NULL; }

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Roland McGrath6551.18%116.67%
Oleg Nesterov5140.16%466.67%
Eric W. Biedermann118.66%116.67%
Total127100.00%6100.00%

/** * ptrace_release_task - final ptrace-related cleanup of a zombie being reaped * @task: task in %EXIT_DEAD state * * Called with write_lock(&tasklist_lock) held. */
static inline void ptrace_release_task(struct task_struct *task) { BUG_ON(!list_empty(&task->ptraced)); ptrace_unlink(task); BUG_ON(!list_empty(&task->ptrace_entry)); }

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Roland McGrath41100.00%1100.00%
Total41100.00%1100.00%

#ifndef force_successful_syscall_return /* * System call handlers that, upon successful completion, need to return a * negative value should call force_successful_syscall_return() right before * returning. On architectures where the syscall convention provides for a * separate error flag (e.g., alpha, ia64, ppc{,64}, sparc{,64}, possibly * others), this macro can be used to ensure that the error flag will not get * set. On architectures which do not support a separate error flag, the macro * is a no-op and the spurious error condition needs to be filtered out by some * other means (e.g., in user-level, by passing an extra argument to the * syscall handler, or something along those lines). */ #define force_successful_syscall_return() do { } while (0) #endif #ifndef is_syscall_success /* * On most systems we can tell if a syscall is a success based on if the retval * is an error value. On some systems like ia64 and powerpc they have different * indicators of success/failure and must define their own. */ #define is_syscall_success(regs) (!IS_ERR_VALUE((unsigned long)(regs_return_value(regs)))) #endif /* * <asm/ptrace.h> should define the following things inside #ifdef __KERNEL__. * * These do-nothing inlines are used when the arch does not * implement single-step. The kerneldoc comments are here * to document the interface for all arch definitions. */ #ifndef arch_has_single_step /** * arch_has_single_step - does this CPU support user-mode single-step? * * If this is defined, then there must be function declarations or * inlines for user_enable_single_step() and user_disable_single_step(). * arch_has_single_step() should evaluate to nonzero iff the machine * supports instruction single-step for user mode. * It can be a constant or it can test a CPU feature bit. */ #define arch_has_single_step() (0) /** * user_enable_single_step - single-step in user-mode task * @task: either current or a task stopped in %TASK_TRACED * * This can only be called when arch_has_single_step() has returned nonzero. * Set @task so that when it returns to user mode, it will trap after the * next single instruction executes. If arch_has_block_step() is defined, * this must clear the effects of user_enable_block_step() too. */
static inline void user_enable_single_step(struct task_struct *task) { BUG(); /* This can never be called. */ }

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Roland McGrath16100.00%1100.00%
Total16100.00%1100.00%

/** * user_disable_single_step - cancel user-mode single-step * @task: either current or a task stopped in %TASK_TRACED * * Clear @task of the effects of user_enable_single_step() and * user_enable_block_step(). This can be called whether or not either * of those was ever called on @task, and even if arch_has_single_step() * returned zero. */
static inline void user_disable_single_step(struct task_struct *task) { }

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Roland McGrath11100.00%1100.00%
Total11100.00%1100.00%

#else extern void user_enable_single_step(struct task_struct *); extern void user_disable_single_step(struct task_struct *); #endif /* arch_has_single_step */ #ifndef arch_has_block_step /** * arch_has_block_step - does this CPU support user-mode block-step? * * If this is defined, then there must be a function declaration or inline * for user_enable_block_step(), and arch_has_single_step() must be defined * too. arch_has_block_step() should evaluate to nonzero iff the machine * supports step-until-branch for user mode. It can be a constant or it * can test a CPU feature bit. */ #define arch_has_block_step() (0) /** * user_enable_block_step - step until branch in user-mode task * @task: either current or a task stopped in %TASK_TRACED * * This can only be called when arch_has_block_step() has returned nonzero, * and will never be called when single-instruction stepping is being used. * Set @task so that when it returns to user mode, it will trap after the * next branch or trap taken. */
static inline void user_enable_block_step(struct task_struct *task) { BUG(); /* This can never be called. */ }

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Roland McGrath16100.00%1100.00%
Total16100.00%1100.00%

#else extern void user_enable_block_step(struct task_struct *); #endif /* arch_has_block_step */ #ifdef ARCH_HAS_USER_SINGLE_STEP_INFO extern void user_single_step_siginfo(struct task_struct *tsk, struct pt_regs *regs, siginfo_t *info); #else
static inline void user_single_step_siginfo(struct task_struct *tsk, struct pt_regs *regs, siginfo_t *info) { memset(info, 0, sizeof(*info)); info->si_signo = SIGTRAP; }

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Oleg Nesterov40100.00%1100.00%
Total40100.00%1100.00%

#endif #ifndef arch_ptrace_stop_needed /** * arch_ptrace_stop_needed - Decide whether arch_ptrace_stop() should be called * @code: current->exit_code value ptrace will stop with * @info: siginfo_t pointer (or %NULL) for signal ptrace will stop with * * This is called with the siglock held, to decide whether or not it's * necessary to release the siglock and call arch_ptrace_stop() with the * same @code and @info arguments. It can be defined to a constant if * arch_ptrace_stop() is never required, or always is. On machines where * this makes sense, it should be defined to a quick test to optimize out * calling arch_ptrace_stop() when it would be superfluous. For example, * if the thread has not been back to user mode since the last stop, the * thread state might indicate that nothing needs to be done. * * This is guaranteed to be invoked once before a task stops for ptrace and * may include arch-specific operations necessary prior to a ptrace stop. */ #define arch_ptrace_stop_needed(code, info) (0) #endif #ifndef arch_ptrace_stop /** * arch_ptrace_stop - Do machine-specific work before stopping for ptrace * @code: current->exit_code value ptrace will stop with * @info: siginfo_t pointer (or %NULL) for signal ptrace will stop with * * This is called with no locks held when arch_ptrace_stop_needed() has * just returned nonzero. It is allowed to block, e.g. for user memory * access. The arch can have machine-specific work to be done before * ptrace stops. On ia64, register backing store gets written back to user * memory here. Since this can be costly (requires dropping the siglock), * we only do it when the arch requires it for this particular stop, as * indicated by arch_ptrace_stop_needed(). */ #define arch_ptrace_stop(code, info) do { } while (0) #endif #ifndef current_pt_regs #define current_pt_regs() task_pt_regs(current) #endif #ifndef ptrace_signal_deliver #define ptrace_signal_deliver() ((void)0) #endif /* * unlike current_pt_regs(), this one is equal to task_pt_regs(current) * on *all* architectures; the only reason to have a per-arch definition * is optimisation. */ #ifndef signal_pt_regs #define signal_pt_regs() task_pt_regs(current) #endif #ifndef current_user_stack_pointer #define current_user_stack_pointer() user_stack_pointer(current_pt_regs()) #endif extern int task_current_syscall(struct task_struct *target, long *callno, unsigned long args[6], unsigned int maxargs, unsigned long *sp, unsigned long *pc); #endif

Overall Contributors

PersonTokensPropCommitsCommitProp
Roland McGrath27925.23%812.70%
Oleg Nesterov17515.82%1219.05%
Tejun Heo11110.04%57.94%
Ingo Molnar1069.58%23.17%
Matthew Dempsky706.33%11.59%
Daniel Jacobowitz534.79%34.76%
Christoph Hellwig514.61%34.76%
Al Viro494.43%69.52%
Eric W. Biedermann433.89%34.76%
Alexey Dobriyan302.71%23.17%
Jann Horn262.35%11.59%
Eric Paris191.72%23.17%
David Howells171.54%11.59%
Matthew Wilcox141.27%11.59%
Stephen D. Smalley121.08%11.59%
Andrew Morton110.99%11.59%
Denys Vlasenko80.72%11.59%
Namhyung Kim80.72%23.17%
Linus Torvalds (pre-git)80.72%23.17%
Will Drewry40.36%11.59%
Tycho Andersen40.36%11.59%
Russell King30.27%11.59%
Frédéric Weisbecker20.18%11.59%
Linus Torvalds20.18%11.59%
Markus Metzger10.09%11.59%
Total1106100.00%63100.00%
Directory: include/linux
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