From a6684999f7c6bddd75cf9755ad7ff44435f72fff Mon Sep 17 00:00:00 2001 From: Sukadev Bhattiprolu Date: Wed, 7 Jan 2009 18:08:50 -0800 Subject: [PATCH] mqueue: fix si_pid value in mqueue do_notify() If a process registers for asynchronous notification on a POSIX message queue, it gets a signal and a siginfo_t structure when a message arrives on the message queue. The si_pid in the siginfo_t structure is set to the PID of the process that sent the message to the message queue. The principle is the following: . when mq_notify(SIGEV_SIGNAL) is called, the caller registers for notification when a msg arrives. The associated pid structure is stroed into inode_info->notify_owner. Let's call this process P1. . when mq_send() is called by say P2, P2 sends a signal to P1 to notify him about msg arrival. The way .si_pid is set today is not correct, since it doesn't take into account the fact that the process that is sending the message might not be in the same namespace as the notified one. This patch proposes to set si_pid to the sender's pid into the notify_owner namespace. Signed-off-by: Nadia Derbey Signed-off-by: Sukadev Bhattiprolu Acked-by: Oleg Nesterov Cc: Roland McGrath Cc: Bastian Blank Cc: Pavel Emelyanov Cc: Eric W. Biederman Acked-by: Serge Hallyn Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- ipc/mqueue.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/ipc/mqueue.c b/ipc/mqueue.c index eddb6247a55..23fdb8492b8 100644 --- a/ipc/mqueue.c +++ b/ipc/mqueue.c @@ -505,7 +505,8 @@ static void __do_notify(struct mqueue_inode_info *info) sig_i.si_errno = 0; sig_i.si_code = SI_MESGQ; sig_i.si_value = info->notify.sigev_value; - sig_i.si_pid = task_tgid_vnr(current); + sig_i.si_pid = task_tgid_nr_ns(current, + ns_of_pid(info->notify_owner)); sig_i.si_uid = current_uid(); kill_pid_info(info->notify.sigev_signo, -- 2.41.1