From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sukadev Bhattiprolu Subject: [RFC][PATCH 7/7][v4] SI_TKILL: Masquerade si_pid when crossing pid ns boundary Date: Wed, 24 Dec 2008 03:53:31 -0800 Message-ID: <20081224115331.GG8020@us.ibm.com> References: <20081224114414.GA7879@us.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20081224114414.GA7879@us.ibm.com> Sender: linux-kernel-owner@vger.kernel.org To: oleg@redhat.com, ebiederm@xmission.com, roland@redhat.com, bastian@waldi.eu.org Cc: daniel@hozac.com, xemul@openvz.org, containers@lists.osdl.org, linux-kernel@vger.kernel.org List-Id: containers.vger.kernel.org From: Sukadev Bhattiprolu Subject: [RFC][PATCH 7/7][v4] SI_TKILL: Masquerade si_pid when crossing pid ns boundary When sending a signal to a process in a descendant namespace, ->si_pid must be set to the pid of sender in receiver's namespace. But if the receiver is exiting (theoretically, ns == NULL), just set ->si_pid to active pid namespace of sender (receiver won't see the signal anyway ?). Signed-off-by: Sukadev Bhattiprolu --- kernel/signal.c | 7 ++++++- 1 files changed, 6 insertions(+), 1 deletions(-) diff --git a/kernel/signal.c b/kernel/signal.c index 5a6aea8..e263c23 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2385,17 +2385,22 @@ static int do_tkill(pid_t tgid, pid_t pid, int sig) struct siginfo info; struct task_struct *p; unsigned long flags; + struct pid_namespace *ns; 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(); rcu_read_lock(); p = find_task_by_vpid(pid); if (p && (tgid <= 0 || task_tgid_vnr(p) == tgid)) { + ns = task_active_pid_ns(p); + if (ns) + info.si_pid = task_tgid_nr_ns(current, ns); + else + info.si_pid = task_tgid_vnr(current); error = check_kill_permission(sig, &info, p); /* * The null signal is a permissions and process existence -- 1.5.2.5