From 62ab4505e3efaf67784f84059e0fb9cedb1728ea Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Sat, 4 Apr 2009 21:01:06 +0000 Subject: [PATCH] signals: implement sys_rt_tgsigqueueinfo sys_kill has the per thread counterpart sys_tgkill. sigqueueinfo is missing a thread directed counterpart. Such an interface is important for migrating applications from other OSes which have the per thread delivery implemented. Signed-off-by: Thomas Gleixner Reviewed-by: Oleg Nesterov Acked-by: Roland McGrath Acked-by: Ulrich Drepper --- include/linux/compat.h | 2 ++ include/linux/signal.h | 2 ++ kernel/compat.c | 11 +++++++++++ kernel/signal.c | 26 ++++++++++++++++++++++++++ 4 files changed, 41 insertions(+) diff --git a/include/linux/compat.h b/include/linux/compat.h index f2ded21f9a3..af931ee43dd 100644 --- a/include/linux/compat.h +++ b/include/linux/compat.h @@ -222,6 +222,8 @@ int copy_siginfo_from_user32(siginfo_t *to, struct compat_siginfo __user *from); int copy_siginfo_to_user32(struct compat_siginfo __user *to, siginfo_t *from); int get_compat_sigevent(struct sigevent *event, const struct compat_sigevent __user *u_event); +long compat_sys_rt_tgsigqueueinfo(compat_pid_t tgid, compat_pid_t pid, int sig, + struct compat_siginfo __user *uinfo); static inline int compat_timeval_compare(struct compat_timeval *lhs, struct compat_timeval *rhs) diff --git a/include/linux/signal.h b/include/linux/signal.h index 84f997f8aa5..c7552836bd9 100644 --- a/include/linux/signal.h +++ b/include/linux/signal.h @@ -235,6 +235,8 @@ static inline int valid_signal(unsigned long sig) extern int next_signal(struct sigpending *pending, sigset_t *mask); extern int group_send_sig_info(int sig, struct siginfo *info, struct task_struct *p); extern int __group_send_sig_info(int, struct siginfo *, struct task_struct *); +extern long do_rt_tgsigqueueinfo(pid_t tgid, pid_t pid, int sig, + siginfo_t *info); extern long do_sigpending(void __user *, unsigned long); extern int sigprocmask(int, sigset_t *, sigset_t *); extern int show_unhandled_signals; diff --git a/kernel/compat.c b/kernel/compat.c index 42d56544460..f6c204f07ea 100644 --- a/kernel/compat.c +++ b/kernel/compat.c @@ -882,6 +882,17 @@ compat_sys_rt_sigtimedwait (compat_sigset_t __user *uthese, } +asmlinkage long +compat_sys_rt_tgsigqueueinfo(compat_pid_t tgid, compat_pid_t pid, int sig, + struct compat_siginfo __user *uinfo) +{ + siginfo_t info; + + if (copy_siginfo_from_user32(&info, uinfo)) + return -EFAULT; + return do_rt_tgsigqueueinfo(tgid, pid, sig, &info); +} + #ifdef __ARCH_WANT_COMPAT_SYS_TIME /* compat_time_t is a 32 bit "long" and needs to get converted. */ diff --git a/kernel/signal.c b/kernel/signal.c index 56d27acad87..f79b3b9f837 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2369,6 +2369,32 @@ SYSCALL_DEFINE3(rt_sigqueueinfo, pid_t, pid, int, sig, return kill_proc_info(sig, &info, pid); } +long do_rt_tgsigqueueinfo(pid_t tgid, pid_t pid, int sig, siginfo_t *info) +{ + /* This is only valid for single tasks */ + if (pid <= 0 || tgid <= 0) + return -EINVAL; + + /* Not even root can pretend to send signals from the kernel. + Nor can they impersonate a kill(), which adds source info. */ + if (info->si_code >= 0) + return -EPERM; + info->si_signo = sig; + + return do_send_specific(tgid, pid, sig, info); +} + +SYSCALL_DEFINE4(rt_tgsigqueueinfo, pid_t, tgid, pid_t, pid, int, sig, + siginfo_t __user *, uinfo) +{ + siginfo_t info; + + if (copy_from_user(&info, uinfo, sizeof(siginfo_t))) + return -EFAULT; + + return do_rt_tgsigqueueinfo(tgid, pid, sig, &info); +} + int do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact) { struct task_struct *t = current;