432 lines
15 KiB
C
432 lines
15 KiB
C
|
#ifndef _LINUX_PTRACE_H
|
||
|
|
#define _LINUX_PTRACE_H
|
||
|
|
|
||
|
|
#include <linux/compiler.h> /* For unlikely. */
|
||
|
|
#include <linux/sched.h> /* For struct task_struct. */
|
||
|
|
#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
|
||
|
|
#define PTRACE_MODE_SCHED 0x20
|
||
|
|
#define PTRACE_MODE_IBPB 0x40
|
||
|
|
|
||
|
|
/* 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)
|
||
|
|
#define PTRACE_MODE_SPEC_IBPB (PTRACE_MODE_ATTACH_REALCREDS | PTRACE_MODE_IBPB)
|
||
|
|
|
||
|
|
/**
|
||
|
|
* 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);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* 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.
|
||
|
|
*
|
||
|
|
* Similar to ptrace_may_access(). Only to be called from context switch
|
||
|
|
* code. Does not call into audit and the regular LSM hooks due to locking
|
||
|
|
* constraints.
|
||
|
|
*/
|
||
|
|
extern bool ptrace_may_access_sched(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);
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline void ptrace_unlink(struct task_struct *child)
|
||
|
|
{
|
||
|
|
if (unlikely(child->ptrace))
|
||
|
|
__ptrace_unlink(child);
|
||
|
|
}
|
||
|
|
|
||
|
|
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;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* 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);
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* 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);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* 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);
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* 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;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* 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));
|
||
|
|
}
|
||
|
|
|
||
|
|
#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. */
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* 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)
|
||
|
|
{
|
||
|
|
}
|
||
|
|
#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. */
|
||
|
|
}
|
||
|
|
#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;
|
||
|
|
}
|
||
|
|
#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
|