|  | /* SPDX-License-Identifier: GPL-2.0 */ | 
|  | #ifndef _LINUX_SCHED_SIGNAL_H | 
|  | #define _LINUX_SCHED_SIGNAL_H | 
|  |  | 
|  | #include <linux/rculist.h> | 
|  | #include <linux/signal.h> | 
|  | #include <linux/sched.h> | 
|  | #include <linux/sched/jobctl.h> | 
|  | #include <linux/sched/task.h> | 
|  | #include <linux/cred.h> | 
|  | #include <linux/refcount.h> | 
|  | #include <linux/pid.h> | 
|  | #include <linux/posix-timers.h> | 
|  | #include <linux/mm_types.h> | 
|  | #include <asm/ptrace.h> | 
|  |  | 
|  | /* | 
|  | * Types defining task->signal and task->sighand and APIs using them: | 
|  | */ | 
|  |  | 
|  | struct sighand_struct { | 
|  | spinlock_t		siglock; | 
|  | refcount_t		count; | 
|  | wait_queue_head_t	signalfd_wqh; | 
|  | struct k_sigaction	action[_NSIG]; | 
|  | }; | 
|  |  | 
|  | /* | 
|  | * Per-process accounting stats: | 
|  | */ | 
|  | struct pacct_struct { | 
|  | int			ac_flag; | 
|  | long			ac_exitcode; | 
|  | unsigned long		ac_mem; | 
|  | u64			ac_utime, ac_stime; | 
|  | unsigned long		ac_minflt, ac_majflt; | 
|  | }; | 
|  |  | 
|  | struct cpu_itimer { | 
|  | u64 expires; | 
|  | u64 incr; | 
|  | }; | 
|  |  | 
|  | /* | 
|  | * This is the atomic variant of task_cputime, which can be used for | 
|  | * storing and updating task_cputime statistics without locking. | 
|  | */ | 
|  | struct task_cputime_atomic { | 
|  | atomic64_t utime; | 
|  | atomic64_t stime; | 
|  | atomic64_t sum_exec_runtime; | 
|  | }; | 
|  |  | 
|  | #define INIT_CPUTIME_ATOMIC \ | 
|  | (struct task_cputime_atomic) {				\ | 
|  | .utime = ATOMIC64_INIT(0),			\ | 
|  | .stime = ATOMIC64_INIT(0),			\ | 
|  | .sum_exec_runtime = ATOMIC64_INIT(0),		\ | 
|  | } | 
|  | /** | 
|  | * struct thread_group_cputimer - thread group interval timer counts | 
|  | * @cputime_atomic:	atomic thread group interval timers. | 
|  | * | 
|  | * This structure contains the version of task_cputime, above, that is | 
|  | * used for thread group CPU timer calculations. | 
|  | */ | 
|  | struct thread_group_cputimer { | 
|  | struct task_cputime_atomic cputime_atomic; | 
|  | }; | 
|  |  | 
|  | struct multiprocess_signals { | 
|  | sigset_t signal; | 
|  | struct hlist_node node; | 
|  | }; | 
|  |  | 
|  | struct core_thread { | 
|  | struct task_struct *task; | 
|  | struct core_thread *next; | 
|  | }; | 
|  |  | 
|  | struct core_state { | 
|  | atomic_t nr_threads; | 
|  | struct core_thread dumper; | 
|  | struct completion startup; | 
|  | }; | 
|  |  | 
|  | /* | 
|  | * NOTE! "signal_struct" does not have its own | 
|  | * locking, because a shared signal_struct always | 
|  | * implies a shared sighand_struct, so locking | 
|  | * sighand_struct is always a proper superset of | 
|  | * the locking of signal_struct. | 
|  | */ | 
|  | struct signal_struct { | 
|  | refcount_t		sigcnt; | 
|  | atomic_t		live; | 
|  | int			nr_threads; | 
|  | int			quick_threads; | 
|  | struct list_head	thread_head; | 
|  |  | 
|  | wait_queue_head_t	wait_chldexit;	/* for wait4() */ | 
|  |  | 
|  | /* current thread group signal load-balancing target: */ | 
|  | struct task_struct	*curr_target; | 
|  |  | 
|  | /* shared signal handling: */ | 
|  | struct sigpending	shared_pending; | 
|  |  | 
|  | /* For collecting multiprocess signals during fork */ | 
|  | struct hlist_head	multiprocess; | 
|  |  | 
|  | /* thread group exit support */ | 
|  | int			group_exit_code; | 
|  | /* notify group_exec_task when notify_count is less or equal to 0 */ | 
|  | int			notify_count; | 
|  | struct task_struct	*group_exec_task; | 
|  |  | 
|  | /* thread group stop support, overloads group_exit_code too */ | 
|  | int			group_stop_count; | 
|  | unsigned int		flags; /* see SIGNAL_* flags below */ | 
|  |  | 
|  | struct core_state *core_state; /* coredumping support */ | 
|  |  | 
|  | /* | 
|  | * PR_SET_CHILD_SUBREAPER marks a process, like a service | 
|  | * manager, to re-parent orphan (double-forking) child processes | 
|  | * to this process instead of 'init'. The service manager is | 
|  | * able to receive SIGCHLD signals and is able to investigate | 
|  | * the process until it calls wait(). All children of this | 
|  | * process will inherit a flag if they should look for a | 
|  | * child_subreaper process at exit. | 
|  | */ | 
|  | unsigned int		is_child_subreaper:1; | 
|  | unsigned int		has_child_subreaper:1; | 
|  |  | 
|  | #ifdef CONFIG_POSIX_TIMERS | 
|  |  | 
|  | /* POSIX.1b Interval Timers */ | 
|  | unsigned int		next_posix_timer_id; | 
|  | struct hlist_head	posix_timers; | 
|  |  | 
|  | /* ITIMER_REAL timer for the process */ | 
|  | struct hrtimer real_timer; | 
|  | ktime_t it_real_incr; | 
|  |  | 
|  | /* | 
|  | * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use | 
|  | * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these | 
|  | * values are defined to 0 and 1 respectively | 
|  | */ | 
|  | struct cpu_itimer it[2]; | 
|  |  | 
|  | /* | 
|  | * Thread group totals for process CPU timers. | 
|  | * See thread_group_cputimer(), et al, for details. | 
|  | */ | 
|  | struct thread_group_cputimer cputimer; | 
|  |  | 
|  | #endif | 
|  | /* Empty if CONFIG_POSIX_TIMERS=n */ | 
|  | struct posix_cputimers posix_cputimers; | 
|  |  | 
|  | /* PID/PID hash table linkage. */ | 
|  | struct pid *pids[PIDTYPE_MAX]; | 
|  |  | 
|  | #ifdef CONFIG_NO_HZ_FULL | 
|  | atomic_t tick_dep_mask; | 
|  | #endif | 
|  |  | 
|  | struct pid *tty_old_pgrp; | 
|  |  | 
|  | /* boolean value for session group leader */ | 
|  | int leader; | 
|  |  | 
|  | struct tty_struct *tty; /* NULL if no tty */ | 
|  |  | 
|  | #ifdef CONFIG_SCHED_AUTOGROUP | 
|  | struct autogroup *autogroup; | 
|  | #endif | 
|  | /* | 
|  | * Cumulative resource counters for dead threads in the group, | 
|  | * and for reaped dead child processes forked by this group. | 
|  | * Live threads maintain their own counters and add to these | 
|  | * in __exit_signal, except for the group leader. | 
|  | */ | 
|  | seqlock_t stats_lock; | 
|  | u64 utime, stime, cutime, cstime; | 
|  | u64 gtime; | 
|  | u64 cgtime; | 
|  | struct prev_cputime prev_cputime; | 
|  | unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw; | 
|  | unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt; | 
|  | unsigned long inblock, oublock, cinblock, coublock; | 
|  | unsigned long maxrss, cmaxrss; | 
|  | struct task_io_accounting ioac; | 
|  |  | 
|  | /* | 
|  | * Cumulative ns of schedule CPU time fo dead threads in the | 
|  | * group, not including a zombie group leader, (This only differs | 
|  | * from jiffies_to_ns(utime + stime) if sched_clock uses something | 
|  | * other than jiffies.) | 
|  | */ | 
|  | unsigned long long sum_sched_runtime; | 
|  |  | 
|  | /* | 
|  | * We don't bother to synchronize most readers of this at all, | 
|  | * because there is no reader checking a limit that actually needs | 
|  | * to get both rlim_cur and rlim_max atomically, and either one | 
|  | * alone is a single word that can safely be read normally. | 
|  | * getrlimit/setrlimit use task_lock(current->group_leader) to | 
|  | * protect this instead of the siglock, because they really | 
|  | * have no need to disable irqs. | 
|  | */ | 
|  | struct rlimit rlim[RLIM_NLIMITS]; | 
|  |  | 
|  | #ifdef CONFIG_BSD_PROCESS_ACCT | 
|  | struct pacct_struct pacct;	/* per-process accounting information */ | 
|  | #endif | 
|  | #ifdef CONFIG_TASKSTATS | 
|  | struct taskstats *stats; | 
|  | #endif | 
|  | #ifdef CONFIG_AUDIT | 
|  | unsigned audit_tty; | 
|  | struct tty_audit_buf *tty_audit_buf; | 
|  | #endif | 
|  |  | 
|  | /* | 
|  | * Thread is the potential origin of an oom condition; kill first on | 
|  | * oom | 
|  | */ | 
|  | bool oom_flag_origin; | 
|  | short oom_score_adj;		/* OOM kill score adjustment */ | 
|  | short oom_score_adj_min;	/* OOM kill score adjustment min value. | 
|  | * Only settable by CAP_SYS_RESOURCE. */ | 
|  | struct mm_struct *oom_mm;	/* recorded mm when the thread group got | 
|  | * killed by the oom killer */ | 
|  |  | 
|  | struct mutex cred_guard_mutex;	/* guard against foreign influences on | 
|  | * credential calculations | 
|  | * (notably. ptrace) | 
|  | * Deprecated do not use in new code. | 
|  | * Use exec_update_lock instead. | 
|  | */ | 
|  | struct rw_semaphore exec_update_lock;	/* Held while task_struct is | 
|  | * being updated during exec, | 
|  | * and may have inconsistent | 
|  | * permissions. | 
|  | */ | 
|  | } __randomize_layout; | 
|  |  | 
|  | /* | 
|  | * Bits in flags field of signal_struct. | 
|  | */ | 
|  | #define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */ | 
|  | #define SIGNAL_STOP_CONTINUED	0x00000002 /* SIGCONT since WCONTINUED reap */ | 
|  | #define SIGNAL_GROUP_EXIT	0x00000004 /* group exit in progress */ | 
|  | /* | 
|  | * Pending notifications to parent. | 
|  | */ | 
|  | #define SIGNAL_CLD_STOPPED	0x00000010 | 
|  | #define SIGNAL_CLD_CONTINUED	0x00000020 | 
|  | #define SIGNAL_CLD_MASK		(SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED) | 
|  |  | 
|  | #define SIGNAL_UNKILLABLE	0x00000040 /* for init: ignore fatal signals */ | 
|  |  | 
|  | #define SIGNAL_STOP_MASK (SIGNAL_CLD_MASK | SIGNAL_STOP_STOPPED | \ | 
|  | SIGNAL_STOP_CONTINUED) | 
|  |  | 
|  | static inline void signal_set_stop_flags(struct signal_struct *sig, | 
|  | unsigned int flags) | 
|  | { | 
|  | WARN_ON(sig->flags & SIGNAL_GROUP_EXIT); | 
|  | sig->flags = (sig->flags & ~SIGNAL_STOP_MASK) | flags; | 
|  | } | 
|  |  | 
|  | extern void flush_signals(struct task_struct *); | 
|  | extern void ignore_signals(struct task_struct *); | 
|  | extern void flush_signal_handlers(struct task_struct *, int force_default); | 
|  | extern int dequeue_signal(sigset_t *mask, kernel_siginfo_t *info, enum pid_type *type); | 
|  |  | 
|  | static inline int kernel_dequeue_signal(void) | 
|  | { | 
|  | struct task_struct *task = current; | 
|  | kernel_siginfo_t __info; | 
|  | enum pid_type __type; | 
|  | int ret; | 
|  |  | 
|  | spin_lock_irq(&task->sighand->siglock); | 
|  | ret = dequeue_signal(&task->blocked, &__info, &__type); | 
|  | spin_unlock_irq(&task->sighand->siglock); | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static inline void kernel_signal_stop(void) | 
|  | { | 
|  | spin_lock_irq(¤t->sighand->siglock); | 
|  | if (current->jobctl & JOBCTL_STOP_DEQUEUED) { | 
|  | current->jobctl |= JOBCTL_STOPPED; | 
|  | set_special_state(TASK_STOPPED); | 
|  | } | 
|  | spin_unlock_irq(¤t->sighand->siglock); | 
|  |  | 
|  | schedule(); | 
|  | } | 
|  |  | 
|  | int force_sig_fault_to_task(int sig, int code, void __user *addr, | 
|  | struct task_struct *t); | 
|  | int force_sig_fault(int sig, int code, void __user *addr); | 
|  | int send_sig_fault(int sig, int code, void __user *addr, struct task_struct *t); | 
|  |  | 
|  | int force_sig_mceerr(int code, void __user *, short); | 
|  | int send_sig_mceerr(int code, void __user *, short, struct task_struct *); | 
|  |  | 
|  | int force_sig_bnderr(void __user *addr, void __user *lower, void __user *upper); | 
|  | int force_sig_pkuerr(void __user *addr, u32 pkey); | 
|  | int send_sig_perf(void __user *addr, u32 type, u64 sig_data); | 
|  |  | 
|  | int force_sig_ptrace_errno_trap(int errno, void __user *addr); | 
|  | int force_sig_fault_trapno(int sig, int code, void __user *addr, int trapno); | 
|  | int send_sig_fault_trapno(int sig, int code, void __user *addr, int trapno, | 
|  | struct task_struct *t); | 
|  | int force_sig_seccomp(int syscall, int reason, bool force_coredump); | 
|  |  | 
|  | extern int send_sig_info(int, struct kernel_siginfo *, struct task_struct *); | 
|  | extern void force_sigsegv(int sig); | 
|  | extern int force_sig_info(struct kernel_siginfo *); | 
|  | extern int __kill_pgrp_info(int sig, struct kernel_siginfo *info, struct pid *pgrp); | 
|  | extern int kill_pid_info(int sig, struct kernel_siginfo *info, struct pid *pid); | 
|  | extern int kill_pid_usb_asyncio(int sig, int errno, sigval_t addr, struct pid *, | 
|  | const struct cred *); | 
|  | extern int kill_pgrp(struct pid *pid, int sig, int priv); | 
|  | extern int kill_pid(struct pid *pid, int sig, int priv); | 
|  | extern __must_check bool do_notify_parent(struct task_struct *, int); | 
|  | extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent); | 
|  | extern void force_sig(int); | 
|  | extern void force_fatal_sig(int); | 
|  | extern void force_exit_sig(int); | 
|  | extern int send_sig(int, struct task_struct *, int); | 
|  | extern int zap_other_threads(struct task_struct *p); | 
|  | extern struct sigqueue *sigqueue_alloc(void); | 
|  | extern void sigqueue_free(struct sigqueue *); | 
|  | extern int send_sigqueue(struct sigqueue *, struct pid *, enum pid_type); | 
|  | extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *); | 
|  |  | 
|  | static inline void clear_notify_signal(void) | 
|  | { | 
|  | clear_thread_flag(TIF_NOTIFY_SIGNAL); | 
|  | smp_mb__after_atomic(); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Returns 'true' if kick_process() is needed to force a transition from | 
|  | * user -> kernel to guarantee expedient run of TWA_SIGNAL based task_work. | 
|  | */ | 
|  | static inline bool __set_notify_signal(struct task_struct *task) | 
|  | { | 
|  | return !test_and_set_tsk_thread_flag(task, TIF_NOTIFY_SIGNAL) && | 
|  | !wake_up_state(task, TASK_INTERRUPTIBLE); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Called to break out of interruptible wait loops, and enter the | 
|  | * exit_to_user_mode_loop(). | 
|  | */ | 
|  | static inline void set_notify_signal(struct task_struct *task) | 
|  | { | 
|  | if (__set_notify_signal(task)) | 
|  | kick_process(task); | 
|  | } | 
|  |  | 
|  | static inline int restart_syscall(void) | 
|  | { | 
|  | set_tsk_thread_flag(current, TIF_SIGPENDING); | 
|  | return -ERESTARTNOINTR; | 
|  | } | 
|  |  | 
|  | static inline int task_sigpending(struct task_struct *p) | 
|  | { | 
|  | return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING)); | 
|  | } | 
|  |  | 
|  | static inline int signal_pending(struct task_struct *p) | 
|  | { | 
|  | /* | 
|  | * TIF_NOTIFY_SIGNAL isn't really a signal, but it requires the same | 
|  | * behavior in terms of ensuring that we break out of wait loops | 
|  | * so that notify signal callbacks can be processed. | 
|  | */ | 
|  | if (unlikely(test_tsk_thread_flag(p, TIF_NOTIFY_SIGNAL))) | 
|  | return 1; | 
|  | return task_sigpending(p); | 
|  | } | 
|  |  | 
|  | static inline int __fatal_signal_pending(struct task_struct *p) | 
|  | { | 
|  | return unlikely(sigismember(&p->pending.signal, SIGKILL)); | 
|  | } | 
|  |  | 
|  | static inline int fatal_signal_pending(struct task_struct *p) | 
|  | { | 
|  | return task_sigpending(p) && __fatal_signal_pending(p); | 
|  | } | 
|  |  | 
|  | static inline int signal_pending_state(unsigned int state, struct task_struct *p) | 
|  | { | 
|  | if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL))) | 
|  | return 0; | 
|  | if (!signal_pending(p)) | 
|  | return 0; | 
|  |  | 
|  | return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * This should only be used in fault handlers to decide whether we | 
|  | * should stop the current fault routine to handle the signals | 
|  | * instead, especially with the case where we've got interrupted with | 
|  | * a VM_FAULT_RETRY. | 
|  | */ | 
|  | static inline bool fault_signal_pending(vm_fault_t fault_flags, | 
|  | struct pt_regs *regs) | 
|  | { | 
|  | return unlikely((fault_flags & VM_FAULT_RETRY) && | 
|  | (fatal_signal_pending(current) || | 
|  | (user_mode(regs) && signal_pending(current)))); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Reevaluate whether the task has signals pending delivery. | 
|  | * Wake the task if so. | 
|  | * This is required every time the blocked sigset_t changes. | 
|  | * callers must hold sighand->siglock. | 
|  | */ | 
|  | extern void recalc_sigpending(void); | 
|  | extern void calculate_sigpending(void); | 
|  |  | 
|  | extern void signal_wake_up_state(struct task_struct *t, unsigned int state); | 
|  |  | 
|  | static inline void signal_wake_up(struct task_struct *t, bool fatal) | 
|  | { | 
|  | unsigned int state = 0; | 
|  | if (fatal && !(t->jobctl & JOBCTL_PTRACE_FROZEN)) { | 
|  | t->jobctl &= ~(JOBCTL_STOPPED | JOBCTL_TRACED); | 
|  | state = TASK_WAKEKILL | __TASK_TRACED; | 
|  | } | 
|  | signal_wake_up_state(t, state); | 
|  | } | 
|  | static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume) | 
|  | { | 
|  | unsigned int state = 0; | 
|  | if (resume) { | 
|  | t->jobctl &= ~JOBCTL_TRACED; | 
|  | state = __TASK_TRACED; | 
|  | } | 
|  | signal_wake_up_state(t, state); | 
|  | } | 
|  |  | 
|  | void task_join_group_stop(struct task_struct *task); | 
|  |  | 
|  | #ifdef TIF_RESTORE_SIGMASK | 
|  | /* | 
|  | * Legacy restore_sigmask accessors.  These are inefficient on | 
|  | * SMP architectures because they require atomic operations. | 
|  | */ | 
|  |  | 
|  | /** | 
|  | * set_restore_sigmask() - make sure saved_sigmask processing gets done | 
|  | * | 
|  | * This sets TIF_RESTORE_SIGMASK and ensures that the arch signal code | 
|  | * will run before returning to user mode, to process the flag.  For | 
|  | * all callers, TIF_SIGPENDING is already set or it's no harm to set | 
|  | * it.  TIF_RESTORE_SIGMASK need not be in the set of bits that the | 
|  | * arch code will notice on return to user mode, in case those bits | 
|  | * are scarce.  We set TIF_SIGPENDING here to ensure that the arch | 
|  | * signal code always gets run when TIF_RESTORE_SIGMASK is set. | 
|  | */ | 
|  | static inline void set_restore_sigmask(void) | 
|  | { | 
|  | set_thread_flag(TIF_RESTORE_SIGMASK); | 
|  | } | 
|  |  | 
|  | static inline void clear_tsk_restore_sigmask(struct task_struct *task) | 
|  | { | 
|  | clear_tsk_thread_flag(task, TIF_RESTORE_SIGMASK); | 
|  | } | 
|  |  | 
|  | static inline void clear_restore_sigmask(void) | 
|  | { | 
|  | clear_thread_flag(TIF_RESTORE_SIGMASK); | 
|  | } | 
|  | static inline bool test_tsk_restore_sigmask(struct task_struct *task) | 
|  | { | 
|  | return test_tsk_thread_flag(task, TIF_RESTORE_SIGMASK); | 
|  | } | 
|  | static inline bool test_restore_sigmask(void) | 
|  | { | 
|  | return test_thread_flag(TIF_RESTORE_SIGMASK); | 
|  | } | 
|  | static inline bool test_and_clear_restore_sigmask(void) | 
|  | { | 
|  | return test_and_clear_thread_flag(TIF_RESTORE_SIGMASK); | 
|  | } | 
|  |  | 
|  | #else	/* TIF_RESTORE_SIGMASK */ | 
|  |  | 
|  | /* Higher-quality implementation, used if TIF_RESTORE_SIGMASK doesn't exist. */ | 
|  | static inline void set_restore_sigmask(void) | 
|  | { | 
|  | current->restore_sigmask = true; | 
|  | } | 
|  | static inline void clear_tsk_restore_sigmask(struct task_struct *task) | 
|  | { | 
|  | task->restore_sigmask = false; | 
|  | } | 
|  | static inline void clear_restore_sigmask(void) | 
|  | { | 
|  | current->restore_sigmask = false; | 
|  | } | 
|  | static inline bool test_restore_sigmask(void) | 
|  | { | 
|  | return current->restore_sigmask; | 
|  | } | 
|  | static inline bool test_tsk_restore_sigmask(struct task_struct *task) | 
|  | { | 
|  | return task->restore_sigmask; | 
|  | } | 
|  | static inline bool test_and_clear_restore_sigmask(void) | 
|  | { | 
|  | if (!current->restore_sigmask) | 
|  | return false; | 
|  | current->restore_sigmask = false; | 
|  | return true; | 
|  | } | 
|  | #endif | 
|  |  | 
|  | static inline void restore_saved_sigmask(void) | 
|  | { | 
|  | if (test_and_clear_restore_sigmask()) | 
|  | __set_current_blocked(¤t->saved_sigmask); | 
|  | } | 
|  |  | 
|  | extern int set_user_sigmask(const sigset_t __user *umask, size_t sigsetsize); | 
|  |  | 
|  | static inline void restore_saved_sigmask_unless(bool interrupted) | 
|  | { | 
|  | if (interrupted) | 
|  | WARN_ON(!signal_pending(current)); | 
|  | else | 
|  | restore_saved_sigmask(); | 
|  | } | 
|  |  | 
|  | static inline sigset_t *sigmask_to_save(void) | 
|  | { | 
|  | sigset_t *res = ¤t->blocked; | 
|  | if (unlikely(test_restore_sigmask())) | 
|  | res = ¤t->saved_sigmask; | 
|  | return res; | 
|  | } | 
|  |  | 
|  | static inline int kill_cad_pid(int sig, int priv) | 
|  | { | 
|  | return kill_pid(cad_pid, sig, priv); | 
|  | } | 
|  |  | 
|  | /* These can be the second arg to send_sig_info/send_group_sig_info.  */ | 
|  | #define SEND_SIG_NOINFO ((struct kernel_siginfo *) 0) | 
|  | #define SEND_SIG_PRIV	((struct kernel_siginfo *) 1) | 
|  |  | 
|  | static inline int __on_sig_stack(unsigned long sp) | 
|  | { | 
|  | #ifdef CONFIG_STACK_GROWSUP | 
|  | return sp >= current->sas_ss_sp && | 
|  | sp - current->sas_ss_sp < current->sas_ss_size; | 
|  | #else | 
|  | return sp > current->sas_ss_sp && | 
|  | sp - current->sas_ss_sp <= current->sas_ss_size; | 
|  | #endif | 
|  | } | 
|  |  | 
|  | /* | 
|  | * True if we are on the alternate signal stack. | 
|  | */ | 
|  | static inline int on_sig_stack(unsigned long sp) | 
|  | { | 
|  | /* | 
|  | * If the signal stack is SS_AUTODISARM then, by construction, we | 
|  | * can't be on the signal stack unless user code deliberately set | 
|  | * SS_AUTODISARM when we were already on it. | 
|  | * | 
|  | * This improves reliability: if user state gets corrupted such that | 
|  | * the stack pointer points very close to the end of the signal stack, | 
|  | * then this check will enable the signal to be handled anyway. | 
|  | */ | 
|  | if (current->sas_ss_flags & SS_AUTODISARM) | 
|  | return 0; | 
|  |  | 
|  | return __on_sig_stack(sp); | 
|  | } | 
|  |  | 
|  | static inline int sas_ss_flags(unsigned long sp) | 
|  | { | 
|  | if (!current->sas_ss_size) | 
|  | return SS_DISABLE; | 
|  |  | 
|  | return on_sig_stack(sp) ? SS_ONSTACK : 0; | 
|  | } | 
|  |  | 
|  | static inline void sas_ss_reset(struct task_struct *p) | 
|  | { | 
|  | p->sas_ss_sp = 0; | 
|  | p->sas_ss_size = 0; | 
|  | p->sas_ss_flags = SS_DISABLE; | 
|  | } | 
|  |  | 
|  | static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig) | 
|  | { | 
|  | if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp)) | 
|  | #ifdef CONFIG_STACK_GROWSUP | 
|  | return current->sas_ss_sp; | 
|  | #else | 
|  | return current->sas_ss_sp + current->sas_ss_size; | 
|  | #endif | 
|  | return sp; | 
|  | } | 
|  |  | 
|  | extern void __cleanup_sighand(struct sighand_struct *); | 
|  | extern void flush_itimer_signals(void); | 
|  |  | 
|  | #define tasklist_empty() \ | 
|  | list_empty(&init_task.tasks) | 
|  |  | 
|  | #define next_task(p) \ | 
|  | list_entry_rcu((p)->tasks.next, struct task_struct, tasks) | 
|  |  | 
|  | #define for_each_process(p) \ | 
|  | for (p = &init_task ; (p = next_task(p)) != &init_task ; ) | 
|  |  | 
|  | extern bool current_is_single_threaded(void); | 
|  |  | 
|  | /* | 
|  | * Without tasklist/siglock it is only rcu-safe if g can't exit/exec, | 
|  | * otherwise next_thread(t) will never reach g after list_del_rcu(g). | 
|  | */ | 
|  | #define while_each_thread(g, t) \ | 
|  | while ((t = next_thread(t)) != g) | 
|  |  | 
|  | #define for_other_threads(p, t)	\ | 
|  | for (t = p; (t = next_thread(t)) != p; ) | 
|  |  | 
|  | #define __for_each_thread(signal, t)	\ | 
|  | list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node, \ | 
|  | lockdep_is_held(&tasklist_lock)) | 
|  |  | 
|  | #define for_each_thread(p, t)		\ | 
|  | __for_each_thread((p)->signal, t) | 
|  |  | 
|  | /* Careful: this is a double loop, 'break' won't work as expected. */ | 
|  | #define for_each_process_thread(p, t)	\ | 
|  | for_each_process(p) for_each_thread(p, t) | 
|  |  | 
|  | typedef int (*proc_visitor)(struct task_struct *p, void *data); | 
|  | void walk_process_tree(struct task_struct *top, proc_visitor, void *); | 
|  |  | 
|  | static inline | 
|  | struct pid *task_pid_type(struct task_struct *task, enum pid_type type) | 
|  | { | 
|  | struct pid *pid; | 
|  | if (type == PIDTYPE_PID) | 
|  | pid = task_pid(task); | 
|  | else | 
|  | pid = task->signal->pids[type]; | 
|  | return pid; | 
|  | } | 
|  |  | 
|  | static inline struct pid *task_tgid(struct task_struct *task) | 
|  | { | 
|  | return task->signal->pids[PIDTYPE_TGID]; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Without tasklist or RCU lock it is not safe to dereference | 
|  | * the result of task_pgrp/task_session even if task == current, | 
|  | * we can race with another thread doing sys_setsid/sys_setpgid. | 
|  | */ | 
|  | static inline struct pid *task_pgrp(struct task_struct *task) | 
|  | { | 
|  | return task->signal->pids[PIDTYPE_PGID]; | 
|  | } | 
|  |  | 
|  | static inline struct pid *task_session(struct task_struct *task) | 
|  | { | 
|  | return task->signal->pids[PIDTYPE_SID]; | 
|  | } | 
|  |  | 
|  | static inline int get_nr_threads(struct task_struct *task) | 
|  | { | 
|  | return task->signal->nr_threads; | 
|  | } | 
|  |  | 
|  | static inline bool thread_group_leader(struct task_struct *p) | 
|  | { | 
|  | return p->exit_signal >= 0; | 
|  | } | 
|  |  | 
|  | static inline | 
|  | bool same_thread_group(struct task_struct *p1, struct task_struct *p2) | 
|  | { | 
|  | return p1->signal == p2->signal; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * returns NULL if p is the last thread in the thread group | 
|  | */ | 
|  | static inline struct task_struct *__next_thread(struct task_struct *p) | 
|  | { | 
|  | return list_next_or_null_rcu(&p->signal->thread_head, | 
|  | &p->thread_node, | 
|  | struct task_struct, | 
|  | thread_node); | 
|  | } | 
|  |  | 
|  | static inline struct task_struct *next_thread(struct task_struct *p) | 
|  | { | 
|  | return __next_thread(p) ?: p->group_leader; | 
|  | } | 
|  |  | 
|  | static inline int thread_group_empty(struct task_struct *p) | 
|  | { | 
|  | return thread_group_leader(p) && | 
|  | list_is_last(&p->thread_node, &p->signal->thread_head); | 
|  | } | 
|  |  | 
|  | #define delay_group_leader(p) \ | 
|  | (thread_group_leader(p) && !thread_group_empty(p)) | 
|  |  | 
|  | extern struct sighand_struct *__lock_task_sighand(struct task_struct *task, | 
|  | unsigned long *flags); | 
|  |  | 
|  | static inline struct sighand_struct *lock_task_sighand(struct task_struct *task, | 
|  | unsigned long *flags) | 
|  | { | 
|  | struct sighand_struct *ret; | 
|  |  | 
|  | ret = __lock_task_sighand(task, flags); | 
|  | (void)__cond_lock(&task->sighand->siglock, ret); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static inline void unlock_task_sighand(struct task_struct *task, | 
|  | unsigned long *flags) | 
|  | { | 
|  | spin_unlock_irqrestore(&task->sighand->siglock, *flags); | 
|  | } | 
|  |  | 
|  | #ifdef CONFIG_LOCKDEP | 
|  | extern void lockdep_assert_task_sighand_held(struct task_struct *task); | 
|  | #else | 
|  | static inline void lockdep_assert_task_sighand_held(struct task_struct *task) { } | 
|  | #endif | 
|  |  | 
|  | static inline unsigned long task_rlimit(const struct task_struct *task, | 
|  | unsigned int limit) | 
|  | { | 
|  | return READ_ONCE(task->signal->rlim[limit].rlim_cur); | 
|  | } | 
|  |  | 
|  | static inline unsigned long task_rlimit_max(const struct task_struct *task, | 
|  | unsigned int limit) | 
|  | { | 
|  | return READ_ONCE(task->signal->rlim[limit].rlim_max); | 
|  | } | 
|  |  | 
|  | static inline unsigned long rlimit(unsigned int limit) | 
|  | { | 
|  | return task_rlimit(current, limit); | 
|  | } | 
|  |  | 
|  | static inline unsigned long rlimit_max(unsigned int limit) | 
|  | { | 
|  | return task_rlimit_max(current, limit); | 
|  | } | 
|  |  | 
|  | #endif /* _LINUX_SCHED_SIGNAL_H */ |