Merge branches 'pm-devfreq', 'powercap', 'pm-docs' and 'pm-tools'

[linux-2.6-microblaze.git] / ipc / mqueue.c

diff --git a/ipc/mqueue.c b/ipc/mqueue.c
index dc8307b..beff0cf 100644 (file)
--- a/ipc/mqueue.c
+++ b/ipc/mqueue.c
@@ -142,6 +142,7 @@ struct mqueue_inode_info {
 
        struct sigevent notify;
        struct pid *notify_owner;
+       u32 notify_self_exec_id;
        struct user_namespace *notify_user_ns;
        struct user_struct *user;       /* user who created, for accounting */
        struct sock *notify_sock;
@@ -773,28 +774,44 @@ static void __do_notify(struct mqueue_inode_info *info)
         * synchronously. */
        if (info->notify_owner &&
            info->attr.mq_curmsgs == 1) {
-               struct kernel_siginfo sig_i;
                switch (info->notify.sigev_notify) {
                case SIGEV_NONE:
                        break;
-               case SIGEV_SIGNAL:
-                       /* sends signal */
+               case SIGEV_SIGNAL: {
+                       struct kernel_siginfo sig_i;
+                       struct task_struct *task;
+
+                       /* do_mq_notify() accepts sigev_signo == 0, why?? */
+                       if (!info->notify.sigev_signo)
+                               break;
 
                        clear_siginfo(&sig_i);
                        sig_i.si_signo = info->notify.sigev_signo;
                        sig_i.si_errno = 0;
                        sig_i.si_code = SI_MESGQ;
                        sig_i.si_value = info->notify.sigev_value;
-                       /* map current pid/uid into info->owner's namespaces */
                        rcu_read_lock();
+                       /* map current pid/uid into info->owner's namespaces */
                        sig_i.si_pid = task_tgid_nr_ns(current,
                                                ns_of_pid(info->notify_owner));
-                       sig_i.si_uid = from_kuid_munged(info->notify_user_ns, current_uid());
+                       sig_i.si_uid = from_kuid_munged(info->notify_user_ns,
+                                               current_uid());
+                       /*
+                        * We can't use kill_pid_info(), this signal should
+                        * bypass check_kill_permission(). It is from kernel
+                        * but si_fromuser() can't know this.
+                        * We do check the self_exec_id, to avoid sending
+                        * signals to programs that don't expect them.
+                        */
+                       task = pid_task(info->notify_owner, PIDTYPE_TGID);
+                       if (task && task->self_exec_id ==
+                                               info->notify_self_exec_id) {
+                               do_send_sig_info(info->notify.sigev_signo,
+                                               &sig_i, task, PIDTYPE_TGID);
+                       }
                        rcu_read_unlock();
-
-                       kill_pid_info(info->notify.sigev_signo,
-                                     &sig_i, info->notify_owner);
                        break;
+               }
                case SIGEV_THREAD:
                        set_cookie(info->notify_cookie, NOTIFY_WOKENUP);
                        netlink_sendskb(info->notify_sock, info->notify_cookie);
@@ -1383,6 +1400,7 @@ retry:
                        info->notify.sigev_signo = notification->sigev_signo;
                        info->notify.sigev_value = notification->sigev_value;
                        info->notify.sigev_notify = SIGEV_SIGNAL;
+                       info->notify_self_exec_id = current->self_exec_id;
                        break;
                }