diff options
Diffstat (limited to 'include/linux/ptrace.h')
| -rw-r--r-- | include/linux/ptrace.h | 245 |
1 files changed, 138 insertions, 107 deletions
diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h index a1147e5dd24..cc79eff4a1a 100644 --- a/include/linux/ptrace.h +++ b/include/linux/ptrace.h @@ -1,75 +1,14 @@ #ifndef _LINUX_PTRACE_H #define _LINUX_PTRACE_H -/* ptrace.h */ -/* structs and defines to help the user use the ptrace system call. */ -/* has the defines to get at the registers. */ - -#define PTRACE_TRACEME 0 -#define PTRACE_PEEKTEXT 1 -#define PTRACE_PEEKDATA 2 -#define PTRACE_PEEKUSR 3 -#define PTRACE_POKETEXT 4 -#define PTRACE_POKEDATA 5 -#define PTRACE_POKEUSR 6 -#define PTRACE_CONT 7 -#define PTRACE_KILL 8 -#define PTRACE_SINGLESTEP 9 - -#define PTRACE_ATTACH 16 -#define PTRACE_DETACH 17 - -#define PTRACE_SYSCALL 24 - -/* 0x4200-0x4300 are reserved for architecture-independent additions. */ -#define PTRACE_SETOPTIONS 0x4200 -#define PTRACE_GETEVENTMSG 0x4201 -#define PTRACE_GETSIGINFO 0x4202 -#define PTRACE_SETSIGINFO 0x4203 +#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> /* - * Generic ptrace interface that exports the architecture specific regsets - * using the corresponding NT_* types (which are also used in the core dump). - * Please note that the NT_PRSTATUS note type in a core dump contains a full - * 'struct elf_prstatus'. But the user_regset for NT_PRSTATUS contains just the - * elf_gregset_t that is the pr_reg field of 'struct elf_prstatus'. For all the - * other user_regset flavors, the user_regset layout and the ELF core dump note - * payload are exactly the same layout. - * - * This interface usage is as follows: - * struct iovec iov = { buf, len}; - * - * ret = ptrace(PTRACE_GETREGSET/PTRACE_SETREGSET, pid, NT_XXX_TYPE, &iov); - * - * On the successful completion, iov.len will be updated by the kernel, - * specifying how much the kernel has written/read to/from the user's iov.buf. - */ -#define PTRACE_GETREGSET 0x4204 -#define PTRACE_SETREGSET 0x4205 - -/* options set using PTRACE_SETOPTIONS */ -#define PTRACE_O_TRACESYSGOOD 0x00000001 -#define PTRACE_O_TRACEFORK 0x00000002 -#define PTRACE_O_TRACEVFORK 0x00000004 -#define PTRACE_O_TRACECLONE 0x00000008 -#define PTRACE_O_TRACEEXEC 0x00000010 -#define PTRACE_O_TRACEVFORKDONE 0x00000020 -#define PTRACE_O_TRACEEXIT 0x00000040 - -#define PTRACE_O_MASK 0x0000007f - -/* Wait extended result codes for the above trace options. */ -#define PTRACE_EVENT_FORK 1 -#define PTRACE_EVENT_VFORK 2 -#define PTRACE_EVENT_CLONE 3 -#define PTRACE_EVENT_EXEC 4 -#define PTRACE_EVENT_VFORK_DONE 5 -#define PTRACE_EVENT_EXIT 6 - -#include <asm/ptrace.h> - -#ifdef __KERNEL__ -/* * Ptrace flags * * The owner ship rules for task->ptrace which holds the ptrace @@ -77,18 +16,24 @@ * 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_TRACESYSGOOD 0x00000004 -#define PT_PTRACE_CAP 0x00000008 /* ptracer can follow suid-exec */ -#define PT_TRACE_FORK 0x00000010 -#define PT_TRACE_VFORK 0x00000020 -#define PT_TRACE_CLONE 0x00000040 -#define PT_TRACE_EXEC 0x00000080 -#define PT_TRACE_VFORK_DONE 0x00000100 -#define PT_TRACE_EXIT 0x00000200 - -#define PT_TRACE_MASK 0x000003f4 +#define PT_PTRACE_CAP 0x00000004 /* ptracer can follow suid-exec */ + +#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) /* single stepping state bits (used on ARM and PA-RISC) */ #define PT_SINGLESTEP_BIT 31 @@ -96,16 +41,11 @@ #define PT_BLOCKSTEP_BIT 30 #define PT_BLOCKSTEP (1<<PT_BLOCKSTEP_BIT) -#include <linux/compiler.h> /* For unlikely. */ -#include <linux/sched.h> /* For struct task_struct. */ - - 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_check_attach(struct task_struct *task, int kill); extern int ptrace_request(struct task_struct *child, long request, unsigned long addr, unsigned long data); extern void ptrace_notify(int exit_code); @@ -113,16 +53,15 @@ extern void __ptrace_link(struct task_struct *child, struct task_struct *new_parent); extern void __ptrace_unlink(struct task_struct *child); extern void exit_ptrace(struct task_struct *tracer); -#define PTRACE_MODE_READ 1 -#define PTRACE_MODE_ATTACH 2 -/* Returns 0 on success, -errno on denial. */ -extern int __ptrace_may_access(struct task_struct *task, unsigned int mode); +#define PTRACE_MODE_READ 0x01 +#define PTRACE_MODE_ATTACH 0x02 +#define PTRACE_MODE_NOAUDIT 0x04 /* Returns true on success, false on denial. */ extern bool ptrace_may_access(struct task_struct *task, unsigned int mode); static inline int ptrace_reparented(struct task_struct *child) { - return child->real_parent != child->parent; + return !same_thread_group(child->real_parent, child->parent); } static inline void ptrace_unlink(struct task_struct *child) @@ -137,36 +76,88 @@ int generic_ptrace_pokedata(struct task_struct *tsk, unsigned long addr, unsigned long data); /** - * task_ptrace - return %PT_* flags that apply to a task - * @task: pointer to &task_struct in question + * ptrace_parent - return the task that is tracing the given task + * @task: task to consider * - * Returns the %PT_* flags that apply to @task. + * 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 int task_ptrace(struct task_struct *task) +static inline struct task_struct *ptrace_parent(struct task_struct *task) { - return task->ptrace; + 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 - * @mask: %PT_* bit to check in @current->ptrace - * @event: %PTRACE_EVENT_* value to report if @mask is set + * @event: %PTRACE_EVENT_* value to report * @message: value for %PTRACE_GETEVENTMSG to return * - * This checks the @mask bit to see if ptrace wants stops for this event. - * If so we stop, reporting @event and @message to the ptrace parent. + * 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 * - * Returns nonzero if we did a ptrace notification, zero if not. + * 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 int ptrace_event(int mask, int event, unsigned long message) +static inline void ptrace_event_pid(int event, struct pid *pid) { - if (mask && likely(!(current->ptrace & mask))) - return 0; - current->ptrace_message = message; - ptrace_notify((event << 8) | SIGTRAP); - return 1; + /* + * 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); } /** @@ -183,11 +174,20 @@ static inline void ptrace_init_task(struct task_struct *child, bool ptrace) { INIT_LIST_HEAD(&child->ptrace_entry); INIT_LIST_HEAD(&child->ptraced); - child->parent = child->real_parent; + child->jobctl = 0; child->ptrace = 0; - if (unlikely(ptrace) && (current->ptrace & PT_PTRACED)) { + child->parent = child->real_parent; + + if (unlikely(ptrace) && current->ptrace) { child->ptrace = current->ptrace; __ptrace_link(child, current->parent); + + 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); } } @@ -219,6 +219,15 @@ static inline void ptrace_release_task(struct task_struct *task) #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__. * @@ -325,6 +334,9 @@ static inline void user_single_step_siginfo(struct task_struct *tsk, * 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 @@ -346,10 +358,29 @@ static inline void user_single_step_siginfo(struct task_struct *tsk, #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 - -#endif |