From 09bca05c90c639f57aae057e0c28f287e61f5a07 Mon Sep 17 00:00:00 2001 From: Sukadev Bhattiprolu Date: Tue, 6 Jan 2009 14:42:45 -0800 Subject: SEND_SIG_NOINFO: masquerade si_pid when crossing pid-ns boundary For SEND_SIG_NOINFO, si_pid is currently set to the pid of sender in sender's active pid namespace. But if the receiver is in a Eg: when parent sends the 'pdeath_signal' to a child that is in a descendant pid namespace, we should set si_pid 0. Signed-off-by: Sukadev Bhattiprolu Acked-By: Roland McGrath Cc: "Eric W. Biederman" Cc: Oleg Nesterov Cc: Pavel Emelyanov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/signal.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'kernel/signal.c') diff --git a/kernel/signal.c b/kernel/signal.c index 8e95855ff3c..31db63b3f88 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -858,7 +858,8 @@ static int send_signal(int sig, struct siginfo *info, struct task_struct *t, q->info.si_signo = sig; q->info.si_errno = 0; q->info.si_code = SI_USER; - q->info.si_pid = task_pid_vnr(current); + q->info.si_pid = task_pid_nr_ns(current, + task_active_pid_ns(t)); q->info.si_uid = current_uid(); break; case (unsigned long) SEND_SIG_PRIV: -- cgit v1.2.3-70-g09d2 From 9cd4fd10437dda6b520cb1410b28f36967a34de8 Mon Sep 17 00:00:00 2001 From: Sukadev Bhattiprolu Date: Tue, 6 Jan 2009 14:42:46 -0800 Subject: SEND_SIG_NOINFO: set si_pid to tgid instead of pid POSIX requires the si_pid to be the process id of the sender, so ->si_pid should really be set to 'tgid'. This change does have following changes in behavior: - When sending pdeath_signal on re-parent to a sub-thread, ->si_pid cannot be used to identify the thread that did the re-parent since it will now show the tgid instead of thread id. - A multi-threaded application that expects to find the specific thread that encountered a SIGPIPE using the ->si_pid will now break. Signed-off-by: Sukadev Bhattiprolu Acked-By: Roland McGrath Cc: "Eric W. Biederman" Cc: Oleg Nesterov Cc: Pavel Emelyanov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/signal.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/signal.c') diff --git a/kernel/signal.c b/kernel/signal.c index 31db63b3f88..3152ac3b62e 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -858,7 +858,7 @@ static int send_signal(int sig, struct siginfo *info, struct task_struct *t, q->info.si_signo = sig; q->info.si_errno = 0; q->info.si_code = SI_USER; - q->info.si_pid = task_pid_nr_ns(current, + q->info.si_pid = task_tgid_nr_ns(current, task_active_pid_ns(t)); q->info.si_uid = current_uid(); break; -- cgit v1.2.3-70-g09d2