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-rw-r--r--ipc/mqueue.c34
1 files changed, 26 insertions, 8 deletions
diff --git a/ipc/mqueue.c b/ipc/mqueue.c
index dc8307bf2d74..beff0cfcd1e8 100644
--- 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;
}