1 files changed, 67 insertions, 27 deletions

diff --git a/kernel/signal.c b/kernel/signal.c
index d8034737db4..ccf1ceedaeb 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -27,7 +27,7 @@
 #include <linux/freezer.h>
 #include <linux/pid_namespace.h>
 #include <linux/nsproxy.h>
-#include <trace/sched.h>
+#include <trace/events/sched.h>
 
 #include <asm/param.h>
 #include <asm/uaccess.h>
@@ -41,8 +41,6 @@
 
 static struct kmem_cache *sigqueue_cachep;
 
-DEFINE_TRACE(sched_signal_send);
-
 static void __user *sig_handler(struct task_struct *t, int sig)
 {
 	return t->sighand->action[sig - 1].sa.sa_handler;
@@ -249,14 +247,19 @@ void flush_sigqueue(struct sigpending *queue)
 /*
  * Flush all pending signals for a task.
  */
+void __flush_signals(struct task_struct *t)
+{
+	clear_tsk_thread_flag(t, TIF_SIGPENDING);
+	flush_sigqueue(&t->pending);
+	flush_sigqueue(&t->signal->shared_pending);
+}
+
 void flush_signals(struct task_struct *t)
 {
 	unsigned long flags;
 
 	spin_lock_irqsave(&t->sighand->siglock, flags);
-	clear_tsk_thread_flag(t, TIF_SIGPENDING);
-	flush_sigqueue(&t->pending);
-	flush_sigqueue(&t->signal->shared_pending);
+	__flush_signals(t);
 	spin_unlock_irqrestore(&t->sighand->siglock, flags);
 }
 
@@ -829,6 +832,7 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t,
 {
 	struct sigpending *pending;
 	struct sigqueue *q;
+	int override_rlimit;
 
 	trace_sched_signal_send(sig, t);
 
@@ -860,9 +864,13 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t,
 	   make sure at least one signal gets delivered and don't
 	   pass on the info struct.  */
 
-	q = __sigqueue_alloc(t, GFP_ATOMIC, (sig < SIGRTMIN &&
-					     (is_si_special(info) ||
-					      info->si_code >= 0)));
+	if (sig < SIGRTMIN)
+		override_rlimit = (is_si_special(info) || info->si_code >= 0);
+	else
+		override_rlimit = 0;
+
+	q = __sigqueue_alloc(t, GFP_ATOMIC | __GFP_NOTRACK_FALSE_POSITIVE,
+		override_rlimit);
 	if (q) {
 		list_add_tail(&q->list, &pending->list);
 		switch ((unsigned long) info) {
@@ -1402,7 +1410,7 @@ int do_notify_parent(struct task_struct *tsk, int sig)
  	/* do_notify_parent_cldstop should have been called instead.  */
  	BUG_ON(task_is_stopped_or_traced(tsk));
 
-	BUG_ON(!tsk->ptrace &&
+	BUG_ON(!task_ptrace(tsk) &&
 	       (tsk->group_leader != tsk || !thread_group_empty(tsk)));
 
 	info.si_signo = sig;
@@ -1441,7 +1449,7 @@ int do_notify_parent(struct task_struct *tsk, int sig)
 
 	psig = tsk->parent->sighand;
 	spin_lock_irqsave(&psig->siglock, flags);
-	if (!tsk->ptrace && sig == SIGCHLD &&
+	if (!task_ptrace(tsk) && sig == SIGCHLD &&
 	    (psig->action[SIGCHLD-1].sa.sa_handler == SIG_IGN ||
 	     (psig->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDWAIT))) {
 		/*
@@ -1478,7 +1486,7 @@ static void do_notify_parent_cldstop(struct task_struct *tsk, int why)
 	struct task_struct *parent;
 	struct sighand_struct *sighand;
 
-	if (tsk->ptrace & PT_PTRACED)
+	if (task_ptrace(tsk))
 		parent = tsk->parent;
 	else {
 		tsk = tsk->group_leader;
@@ -1491,7 +1499,7 @@ static void do_notify_parent_cldstop(struct task_struct *tsk, int why)
 	 * see comment in do_notify_parent() abot the following 3 lines
 	 */
 	rcu_read_lock();
-	info.si_pid = task_pid_nr_ns(tsk, tsk->parent->nsproxy->pid_ns);
+	info.si_pid = task_pid_nr_ns(tsk, parent->nsproxy->pid_ns);
 	info.si_uid = __task_cred(tsk)->uid;
 	rcu_read_unlock();
 
@@ -1527,7 +1535,7 @@ static void do_notify_parent_cldstop(struct task_struct *tsk, int why)
 
 static inline int may_ptrace_stop(void)
 {
-	if (!likely(current->ptrace & PT_PTRACED))
+	if (!likely(task_ptrace(current)))
 		return 0;
 	/*
 	 * Are we in the middle of do_coredump?
@@ -1745,7 +1753,7 @@ static int do_signal_stop(int signr)
 static int ptrace_signal(int signr, siginfo_t *info,
 			 struct pt_regs *regs, void *cookie)
 {
-	if (!(current->ptrace & PT_PTRACED))
+	if (!task_ptrace(current))
 		return signr;
 
 	ptrace_signal_deliver(regs, cookie);
@@ -2278,24 +2286,17 @@ SYSCALL_DEFINE2(kill, pid_t, pid, int, sig)
 	return kill_something_info(sig, &info, pid);
 }
 
-static int do_tkill(pid_t tgid, pid_t pid, int sig)
+static int
+do_send_specific(pid_t tgid, pid_t pid, int sig, struct siginfo *info)
 {
-	int error;
-	struct siginfo info;
 	struct task_struct *p;
 	unsigned long flags;
-
-	error = -ESRCH;
-	info.si_signo = sig;
-	info.si_errno = 0;
-	info.si_code = SI_TKILL;
-	info.si_pid = task_tgid_vnr(current);
-	info.si_uid = current_uid();
+	int error = -ESRCH;
 
 	rcu_read_lock();
 	p = find_task_by_vpid(pid);
 	if (p && (tgid <= 0 || task_tgid_vnr(p) == tgid)) {
-		error = check_kill_permission(sig, &info, p);
+		error = check_kill_permission(sig, info, p);
 		/*
 		 * The null signal is a permissions and process existence
 		 * probe.  No signal is actually delivered.
@@ -2305,7 +2306,7 @@ static int do_tkill(pid_t tgid, pid_t pid, int sig)
 		 * signal is private anyway.
 		 */
 		if (!error && sig && lock_task_sighand(p, &flags)) {
-			error = specific_send_sig_info(sig, &info, p);
+			error = specific_send_sig_info(sig, info, p);
 			unlock_task_sighand(p, &flags);
 		}
 	}
@@ -2314,6 +2315,19 @@ static int do_tkill(pid_t tgid, pid_t pid, int sig)
 	return error;
 }
 
+static int do_tkill(pid_t tgid, pid_t pid, int sig)
+{
+	struct siginfo info;
+
+	info.si_signo = sig;
+	info.si_errno = 0;
+	info.si_code = SI_TKILL;
+	info.si_pid = task_tgid_vnr(current);
+	info.si_uid = current_uid();
+
+	return do_send_specific(tgid, pid, sig, &info);
+}
+
 /**
  *  sys_tgkill - send signal to one specific thread
  *  @tgid: the thread group ID of the thread
@@ -2363,6 +2377,32 @@ 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;