67 static void __user *sig_handler(struct task_struct *t, int sig)  in sig_handler()  argument
69 	return t->sighand->action[sig - 1].sa.sa_handler;  in sig_handler()
72 static inline bool sig_handler_ignored(void __user *handler, int sig)  in sig_handler_ignored()  argument
76 	       (handler == SIG_DFL && sig_kernel_ignore(sig));  in sig_handler_ignored()
79 static bool sig_task_ignored(struct task_struct *t, int sig, bool force)  in sig_task_ignored()  argument
83 	handler = sig_handler(t, sig);  in sig_task_ignored()
86 	if (unlikely(is_global_init(t) && sig_kernel_only(sig)))  in sig_task_ignored()
90 	    handler == SIG_DFL && !(force && sig_kernel_only(sig)))  in sig_task_ignored()
98 	return sig_handler_ignored(handler, sig);  in sig_task_ignored()
101 static bool sig_ignored(struct task_struct *t, int sig, bool force)  in sig_ignored()  argument
108 	if (sigismember(&t->blocked, sig) || sigismember(&t->real_blocked, sig))  in sig_ignored()
116 	if (t->ptrace && sig != SIGKILL)  in sig_ignored()
119 	return sig_task_ignored(t, sig, force);  in sig_ignored()
134 			ready |= signal->sig[i] &~ blocked->sig[i];  in has_pending_signals()
137 	case 4: ready  = signal->sig[3] &~ blocked->sig[3];  in has_pending_signals()
138 		ready |= signal->sig[2] &~ blocked->sig[2];  in has_pending_signals()
139 		ready |= signal->sig[1] &~ blocked->sig[1];  in has_pending_signals()
140 		ready |= signal->sig[0] &~ blocked->sig[0];  in has_pending_signals()
143 	case 2: ready  = signal->sig[1] &~ blocked->sig[1];  in has_pending_signals()
144 		ready |= signal->sig[0] &~ blocked->sig[0];  in has_pending_signals()
147 	case 1: ready  = signal->sig[0] &~ blocked->sig[0];  in has_pending_signals()
211 	int sig = 0;  in next_signal()  local
213 	s = pending->signal.sig;  in next_signal()
214 	m = mask->sig;  in next_signal()
224 		sig = ffz(~x) + 1;  in next_signal()
225 		return sig;  in next_signal()
234 			sig = ffz(~x) + i*_NSIG_BPW + 1;  in next_signal()
243 		sig = ffz(~x) + _NSIG_BPW + 1;  in next_signal()
251 	return sig;  in next_signal()
254 static inline void print_dropped_signal(int sig)  in print_dropped_signal()  argument
265 				current->comm, current->pid, sig);  in print_dropped_signal()
368 	struct signal_struct *sig = task->signal;  in task_participate_group_stop()  local
378 	if (!WARN_ON_ONCE(sig->group_stop_count == 0))  in task_participate_group_stop()
379 		sig->group_stop_count--;  in task_participate_group_stop()
385 	if (!sig->group_stop_count && !(sig->flags & SIGNAL_STOP_STOPPED)) {  in task_participate_group_stop()
386 		signal_set_stop_flags(sig, SIGNAL_STOP_STOPPED);  in task_participate_group_stop()
395 	struct signal_struct *sig = current->signal;  in task_join_group_stop()  local
397 	if (sig->group_stop_count) {  in task_join_group_stop()
398 		sig->group_stop_count++;  in task_join_group_stop()
400 	} else if (!(sig->flags & SIGNAL_STOP_STOPPED))  in task_join_group_stop()
413 __sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimit)  in __sigqueue_alloc()  argument
437 		print_dropped_signal(sig);  in __sigqueue_alloc()
498 		int sig = q->info.si_signo;  in __flush_itimer_signals()  local
501 			sigaddset(&retain, sig);  in __flush_itimer_signals()
503 			sigdelset(&signal, sig);  in __flush_itimer_signals()
555 bool unhandled_signal(struct task_struct *tsk, int sig)  in unhandled_signal()  argument
557 	void __user *handler = tsk->sighand->action[sig-1].sa.sa_handler;  in unhandled_signal()
568 static void collect_signal(int sig, struct sigpending *list, kernel_siginfo_t *info,  in collect_signal()  argument
578 		if (q->info.si_signo == sig) {  in collect_signal()
585 	sigdelset(&list->signal, sig);  in collect_signal()
605 		info->si_signo = sig;  in collect_signal()
616 	int sig = next_signal(pending, mask);  in __dequeue_signal()  local
618 	if (sig)  in __dequeue_signal()
619 		collect_signal(sig, pending, info, resched_timer);  in __dequeue_signal()
620 	return sig;  in __dequeue_signal()
716 	if (!((pending->signal.sig[0] & ~tsk->blocked.sig[0]) & SYNCHRONOUS_MASK))  in dequeue_synchronous_signal()
828 static int check_kill_permission(int sig, struct kernel_siginfo *info,  in check_kill_permission()  argument
834 	if (!valid_signal(sig))  in check_kill_permission()
840 	error = audit_signal_info(sig, t); /* Let audit system see the signal */  in check_kill_permission()
846 		switch (sig) {  in check_kill_permission()
861 	return security_task_kill(t, info, sig, NULL);  in check_kill_permission()
900 static bool prepare_signal(int sig, struct task_struct *p, bool force)  in prepare_signal()  argument
908 			return sig == SIGKILL;  in prepare_signal()
912 	} else if (sig_kernel_stop(sig)) {  in prepare_signal()
920 	} else if (sig == SIGCONT) {  in prepare_signal()
962 	return !sig_ignored(p, sig, force);  in prepare_signal()
973 static inline bool wants_signal(int sig, struct task_struct *p)  in wants_signal()  argument
975 	if (sigismember(&p->blocked, sig))  in wants_signal()
981 	if (sig == SIGKILL)  in wants_signal()
990 static void complete_signal(int sig, struct task_struct *p, enum pid_type type)  in complete_signal()  argument
1001 	if (wants_signal(sig, p))  in complete_signal()
1014 		while (!wants_signal(sig, t)) {  in complete_signal()
1031 	if (sig_fatal(p, sig) &&  in complete_signal()
1033 	    !sigismember(&t->real_blocked, sig) &&  in complete_signal()
1034 	    (sig == SIGKILL || !p->ptrace)) {  in complete_signal()
1038 		if (!sig_kernel_coredump(sig)) {  in complete_signal()
1046 			signal->group_exit_code = sig;  in complete_signal()
1062 	signal_wake_up(t, sig == SIGKILL);  in complete_signal()
1066 static inline bool legacy_queue(struct sigpending *signals, int sig)  in legacy_queue()  argument
1068 	return (sig < SIGRTMIN) && sigismember(&signals->signal, sig);  in legacy_queue()
1071 static int __send_signal(int sig, struct kernel_siginfo *info, struct task_struct *t,  in __send_signal()  argument
1082 	if (!prepare_signal(sig, t, force))  in __send_signal()
1092 	if (legacy_queue(pending, sig))  in __send_signal()
1099 	if ((sig == SIGKILL) || (t->flags & PF_KTHREAD))  in __send_signal()
1111 	if (sig < SIGRTMIN)  in __send_signal()
1116 	q = __sigqueue_alloc(sig, t, GFP_ATOMIC, override_rlimit);  in __send_signal()
1122 			q->info.si_signo = sig;  in __send_signal()
1135 			q->info.si_signo = sig;  in __send_signal()
1146 		   sig >= SIGRTMIN && info->si_code != SI_USER) {  in __send_signal()
1164 	signalfd_notify(t, sig);  in __send_signal()
1165 	sigaddset(&pending->signal, sig);  in __send_signal()
1173 			if (sig == SIGCONT)  in __send_signal()
1175 			else if (sig_kernel_stop(sig))  in __send_signal()
1177 			sigaddset(signal, sig);  in __send_signal()
1181 	complete_signal(sig, t, type);  in __send_signal()
1183 	trace_signal_generate(sig, info, t, type != PIDTYPE_PID, result);  in __send_signal()
1209 static int send_signal(int sig, struct kernel_siginfo *info, struct task_struct *t,  in send_signal()  argument
1242 	return __send_signal(sig, info, t, type, force);  in send_signal()
1279 __group_send_sig_info(int sig, struct kernel_siginfo *info, struct task_struct *p)  in __group_send_sig_info()  argument
1281 	return send_signal(sig, info, p, PIDTYPE_TGID);  in __group_send_sig_info()
1284 int do_send_sig_info(int sig, struct kernel_siginfo *info, struct task_struct *p,  in do_send_sig_info()  argument
1291 		ret = send_signal(sig, info, p, type);  in do_send_sig_info()
1315 	int sig = info->si_signo;  in force_sig_info_to_task()  local
1318 	action = &t->sighand->action[sig-1];  in force_sig_info_to_task()
1320 	blocked = sigismember(&t->blocked, sig);  in force_sig_info_to_task()
1324 			sigdelset(&t->blocked, sig);  in force_sig_info_to_task()
1334 	ret = send_signal(sig, info, t, PIDTYPE_PID);  in force_sig_info_to_task()
1404 int group_send_sig_info(int sig, struct kernel_siginfo *info,  in group_send_sig_info()  argument
1410 	ret = check_kill_permission(sig, info, p);  in group_send_sig_info()
1413 	if (!ret && sig)  in group_send_sig_info()
1414 		ret = do_send_sig_info(sig, info, p, type);  in group_send_sig_info()
1424 int __kill_pgrp_info(int sig, struct kernel_siginfo *info, struct pid *pgrp)  in __kill_pgrp_info()  argument
1432 		int err = group_send_sig_info(sig, info, p, PIDTYPE_PGID);  in __kill_pgrp_info()
1439 int kill_pid_info(int sig, struct kernel_siginfo *info, struct pid *pid)  in kill_pid_info()  argument
1448 			error = group_send_sig_info(sig, info, p, PIDTYPE_TGID);  in kill_pid_info()
1461 static int kill_proc_info(int sig, struct kernel_siginfo *info, pid_t pid)  in kill_proc_info()  argument
1465 	error = kill_pid_info(sig, info, find_vpid(pid));  in kill_proc_info()
1506 int kill_pid_usb_asyncio(int sig, int errno, sigval_t addr,  in kill_pid_usb_asyncio()  argument
1514 	if (!valid_signal(sig))  in kill_pid_usb_asyncio()
1518 	info.si_signo = sig;  in kill_pid_usb_asyncio()
1533 	ret = security_task_kill(p, &info, sig, cred);  in kill_pid_usb_asyncio()
1537 	if (sig) {  in kill_pid_usb_asyncio()
1539 			ret = __send_signal(sig, &info, p, PIDTYPE_TGID, false);  in kill_pid_usb_asyncio()
1557 static int kill_something_info(int sig, struct kernel_siginfo *info, pid_t pid)  in kill_something_info()  argument
1562 		return kill_proc_info(sig, info, pid);  in kill_something_info()
1570 		ret = __kill_pgrp_info(sig, info,  in kill_something_info()
1579 				int err = group_send_sig_info(sig, info, p,  in kill_something_info()
1597 int send_sig_info(int sig, struct kernel_siginfo *info, struct task_struct *p)  in send_sig_info()  argument
1603 	if (!valid_signal(sig))  in send_sig_info()
1606 	return do_send_sig_info(sig, info, p, PIDTYPE_PID);  in send_sig_info()
1614 send_sig(int sig, struct task_struct *p, int priv)  in send_sig()  argument
1616 	return send_sig_info(sig, __si_special(priv), p);  in send_sig()
1620 void force_sig(int sig)  in force_sig()  argument
1625 	info.si_signo = sig;  in force_sig()
1640 void force_sigsegv(int sig)  in force_sigsegv()  argument
1644 	if (sig == SIGSEGV) {  in force_sigsegv()
1647 		p->sighand->action[sig - 1].sa.sa_handler = SIG_DFL;  in force_sigsegv()
1653 int force_sig_fault_to_task(int sig, int code, void __user *addr  in force_sig_fault_to_task()  argument
1661 	info.si_signo = sig;  in force_sig_fault_to_task()
1676 int force_sig_fault(int sig, int code, void __user *addr  in force_sig_fault()  argument
1680 	return force_sig_fault_to_task(sig, code, addr  in force_sig_fault()
1685 int send_sig_fault(int sig, int code, void __user *addr  in send_sig_fault()  argument
1693 	info.si_signo = sig;  in send_sig_fault()
1781 int kill_pgrp(struct pid *pid, int sig, int priv)  in kill_pgrp()  argument
1786 	ret = __kill_pgrp_info(sig, __si_special(priv), pid);  in kill_pgrp()
1793 int kill_pid(struct pid *pid, int sig, int priv)  in kill_pid()  argument
1795 	return kill_pid_info(sig, __si_special(priv), pid);  in kill_pid()
1845 	int sig = q->info.si_signo;  in send_sigqueue()  local
1861 	if (!prepare_signal(sig, t, false))  in send_sigqueue()
1877 	signalfd_notify(t, sig);  in send_sigqueue()
1880 	sigaddset(&pending->signal, sig);  in send_sigqueue()
1881 	complete_signal(sig, t, type);  in send_sigqueue()
1884 	trace_signal_generate(sig, &q->info, t, type != PIDTYPE_PID, result);  in send_sigqueue()
1907 bool do_notify_parent(struct task_struct *tsk, int sig)  in do_notify_parent()  argument
1915 	BUG_ON(sig == -1);  in do_notify_parent()
1926 	if (sig != SIGCHLD) {  in do_notify_parent()
1932 			sig = SIGCHLD;  in do_notify_parent()
1936 	info.si_signo = sig;  in do_notify_parent()
1971 	if (!tsk->ptrace && sig == SIGCHLD &&  in do_notify_parent()
1991 			sig = 0;  in do_notify_parent()
1997 	if (valid_signal(sig) && sig)  in do_notify_parent()
1998 		__send_signal(sig, &info, tsk->parent, PIDTYPE_TGID, false);  in do_notify_parent()
2308 	struct signal_struct *sig = current->signal;  in do_signal_stop()  local
2318 		    unlikely(signal_group_exit(sig)))  in do_signal_stop()
2339 		if (!(sig->flags & SIGNAL_STOP_STOPPED))  in do_signal_stop()
2340 			sig->group_exit_code = signr;  in do_signal_stop()
2342 		sig->group_stop_count = 0;  in do_signal_stop()
2345 			sig->group_stop_count++;  in do_signal_stop()
2356 				sig->group_stop_count++;  in do_signal_stop()
2763 	ksig->sig = signr;  in get_signal()
2764 	return ksig->sig > 0;  in get_signal()
2789 		sigaddset(&blocked, ksig->sig);  in signal_delivered()
2797 		force_sigsegv(ksig->sig);  in signal_setup_done()
3152 static bool known_siginfo_layout(unsigned sig, int si_code)  in known_siginfo_layout()  argument
3157 		if (sig_specific_sicodes(sig)) {  in known_siginfo_layout()
3158 			if (si_code <= sig_sicodes[sig].limit)  in known_siginfo_layout()
3171 enum siginfo_layout siginfo_layout(unsigned sig, int si_code)  in siginfo_layout()  argument
3175 		if ((sig < ARRAY_SIZE(sig_sicodes)) &&  in siginfo_layout()
3176 		    (si_code <= sig_sicodes[sig].limit)) {  in siginfo_layout()
3177 			layout = sig_sicodes[sig].layout;  in siginfo_layout()
3179 			if ((sig == SIGBUS) &&  in siginfo_layout()
3182 			else if ((sig == SIGSEGV) && (si_code == SEGV_BNDERR))  in siginfo_layout()
3185 			else if ((sig == SIGSEGV) && (si_code == SEGV_PKUERR))  in siginfo_layout()
3462 	int sig, ret = 0;  in do_sigtimedwait()  local
3478 	sig = dequeue_signal(tsk, &mask, info);  in do_sigtimedwait()
3479 	if (!sig && timeout) {  in do_sigtimedwait()
3497 		sig = dequeue_signal(tsk, &mask, info);  in do_sigtimedwait()
3501 	if (sig)  in do_sigtimedwait()
3502 		return sig;  in do_sigtimedwait()
3643 static inline void prepare_kill_siginfo(int sig, struct kernel_siginfo *info)  in prepare_kill_siginfo()  argument
3646 	info->si_signo = sig;  in prepare_kill_siginfo()
3658 SYSCALL_DEFINE2(kill, pid_t, pid, int, sig)  in SYSCALL_DEFINE2()  argument
3662 	prepare_kill_siginfo(sig, &info);  in SYSCALL_DEFINE2()
3664 	return kill_something_info(sig, &info, pid);  in SYSCALL_DEFINE2()
3732 SYSCALL_DEFINE4(pidfd_send_signal, int, pidfd, int, sig,  in SYSCALL_DEFINE4()  argument
3765 		if (unlikely(sig != kinfo.si_signo))  in SYSCALL_DEFINE4()
3774 		prepare_kill_siginfo(sig, &kinfo);  in SYSCALL_DEFINE4()
3777 	ret = kill_pid_info(sig, &kinfo, pid);  in SYSCALL_DEFINE4()
3785 do_send_specific(pid_t tgid, pid_t pid, int sig, struct kernel_siginfo *info)  in do_send_specific()  argument
3793 		error = check_kill_permission(sig, info, p);  in do_send_specific()
3798 		if (!error && sig) {  in do_send_specific()
3799 			error = do_send_sig_info(sig, info, p, PIDTYPE_PID);  in do_send_specific()
3814 static int do_tkill(pid_t tgid, pid_t pid, int sig)  in do_tkill()  argument
3819 	info.si_signo = sig;  in do_tkill()
3825 	return do_send_specific(tgid, pid, sig, &info);  in do_tkill()
3838 SYSCALL_DEFINE3(tgkill, pid_t, tgid, pid_t, pid, int, sig)  in SYSCALL_DEFINE3()  argument
3844 	return do_tkill(tgid, pid, sig);  in SYSCALL_DEFINE3()
3854 SYSCALL_DEFINE2(tkill, pid_t, pid, int, sig)  in SYSCALL_DEFINE2()  argument
3860 	return do_tkill(0, pid, sig);  in SYSCALL_DEFINE2()
3863 static int do_rt_sigqueueinfo(pid_t pid, int sig, kernel_siginfo_t *info)  in do_rt_sigqueueinfo()  argument
3873 	return kill_proc_info(sig, info, pid);  in do_rt_sigqueueinfo()
3882 SYSCALL_DEFINE3(rt_sigqueueinfo, pid_t, pid, int, sig,  in SYSCALL_DEFINE3()  argument
3886 	int ret = __copy_siginfo_from_user(sig, &info, uinfo);  in SYSCALL_DEFINE3()
3889 	return do_rt_sigqueueinfo(pid, sig, &info);  in SYSCALL_DEFINE3()
3895 			int, sig,  in COMPAT_SYSCALL_DEFINE3()
3899 	int ret = __copy_siginfo_from_user32(sig, &info, uinfo);  in COMPAT_SYSCALL_DEFINE3()
3902 	return do_rt_sigqueueinfo(pid, sig, &info);  in COMPAT_SYSCALL_DEFINE3()
3906 static int do_rt_tgsigqueueinfo(pid_t tgid, pid_t pid, int sig, kernel_siginfo_t *info)  in do_rt_tgsigqueueinfo()  argument
3919 	return do_send_specific(tgid, pid, sig, info);  in do_rt_tgsigqueueinfo()
3922 SYSCALL_DEFINE4(rt_tgsigqueueinfo, pid_t, tgid, pid_t, pid, int, sig,  in SYSCALL_DEFINE4()  argument
3926 	int ret = __copy_siginfo_from_user(sig, &info, uinfo);  in SYSCALL_DEFINE4()
3929 	return do_rt_tgsigqueueinfo(tgid, pid, sig, &info);  in SYSCALL_DEFINE4()
3936 			int, sig,  in COMPAT_SYSCALL_DEFINE4()
3940 	int ret = __copy_siginfo_from_user32(sig, &info, uinfo);  in COMPAT_SYSCALL_DEFINE4()
3943 	return do_rt_tgsigqueueinfo(tgid, pid, sig, &info);  in COMPAT_SYSCALL_DEFINE4()
3950 void kernel_sigaction(int sig, __sighandler_t action)  in kernel_sigaction()  argument
3953 	current->sighand->action[sig - 1].sa.sa_handler = action;  in kernel_sigaction()
3958 		sigaddset(&mask, sig);  in kernel_sigaction()
3973 int do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact)  in do_sigaction()  argument
3979 	if (!valid_signal(sig) || sig < 1 || (act && sig_kernel_only(sig)))  in do_sigaction()
3982 	k = &p->sighand->action[sig-1];  in do_sigaction()
4005 		if (sig_handler_ignored(sig_handler(p, sig), sig)) {  in do_sigaction()
4007 			sigaddset(&mask, sig);  in do_sigaction()
4187 	return put_user(set.sig[0], set32);  in COMPAT_SYSCALL_DEFINE1()
4210 	old_set = current->blocked.sig[0];  in SYSCALL_DEFINE3()
4226 			new_blocked.sig[0] = new_set;  in SYSCALL_DEFINE3()
4252 SYSCALL_DEFINE4(rt_sigaction, int, sig,  in SYSCALL_DEFINE4()  argument
4267 	ret = do_sigaction(sig, act ? &new_sa : NULL, oact ? &old_sa : NULL);  in SYSCALL_DEFINE4()
4277 COMPAT_SYSCALL_DEFINE4(rt_sigaction, int, sig,  in COMPAT_SYSCALL_DEFINE4()  argument
4306 	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);  in COMPAT_SYSCALL_DEFINE4()
4324 SYSCALL_DEFINE3(sigaction, int, sig,  in SYSCALL_DEFINE3()  argument
4345 	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);  in SYSCALL_DEFINE3()
4352 		    __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))  in SYSCALL_DEFINE3()
4360 COMPAT_SYSCALL_DEFINE3(sigaction, int, sig,  in COMPAT_SYSCALL_DEFINE3()  argument
4385 	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);  in COMPAT_SYSCALL_DEFINE3()
4394 		    __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))  in COMPAT_SYSCALL_DEFINE3()
4409 	return current->blocked.sig[0];  in SYSCALL_DEFINE0()
4414 	int old = current->blocked.sig[0];  in SYSCALL_DEFINE1()
4428 SYSCALL_DEFINE2(signal, int, sig, __sighandler_t, handler)  in SYSCALL_DEFINE2()  argument
4437 	ret = do_sigaction(sig, &new_sa, &old_sa);  in SYSCALL_DEFINE2()
4609 void kdb_send_sig(struct task_struct *t, int sig)  in kdb_send_sig()  argument
4631 	ret = send_signal(sig, SEND_SIG_PRIV, t, PIDTYPE_PID);  in kdb_send_sig()
4635 			   sig, t->pid);  in kdb_send_sig()
4637 		kdb_printf("Signal %d is sent to process %d.\n", sig, t->pid);  in kdb_send_sig()