[CRIU] [PATCH 6/7] crtools: restore pending signals

[Andrey Vagin]

Only shared signals are restored by now

Signed-off-by: Andrey Vagin <avagin at openvz.org>
---
 cr-restore.c       |  6 ++++++
 include/restorer.h |  1 +
 pie/restorer.c     | 41 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 48 insertions(+)

diff --git a/cr-restore.c b/cr-restore.c
index 78ee82d..9cf328e 100644
--- a/cr-restore.c
+++ b/cr-restore.c
@@ -1719,6 +1719,12 @@ static int sigreturn_restore(pid_t pid, CoreEntry *core)
 	task_args	= mem;
 	thread_args	= mem + restore_task_vma_len;
 
+	task_args->signal_img_fd = open_image_ro(CR_FD_SIGNAL, pid);
+	if (task_args->signal_img_fd < 0) {
+		if (errno != ENOENT) /* backward compatiblity */
+			goto err;
+	}
+
 	/*
 	 * Adjust stack.
 	 */
diff --git a/include/restorer.h b/include/restorer.h
index e4332a0..650f8b1 100644
--- a/include/restorer.h
+++ b/include/restorer.h
@@ -86,6 +86,7 @@ struct task_restore_core_args {
 
 	int				fd_exe_link;		/* opened self->exe file */
 	int				logfd;
+	int				signal_img_fd;
 	unsigned int			loglevel;
 
 	mutex_t				rst_lock;
diff --git a/pie/restorer.c b/pie/restorer.c
index 95dca19..5a02573 100644
--- a/pie/restorer.c
+++ b/pie/restorer.c
@@ -400,6 +400,40 @@ static int vma_remap(unsigned long src, unsigned long dst, unsigned long len)
 	return 0;
 }
 
+static int restore_signals(struct task_restore_core_args *args)
+{
+	int ret;
+	k_rtsigset_t to_block;
+
+	ksigfillset(&to_block);
+	ret = sys_sigprocmask(SIG_SETMASK, &to_block, NULL, sizeof(k_rtsigset_t));
+	if (ret) {
+		pr_err("Unable to block signals %d", ret);
+		return -1;
+	}
+
+	while (1) {
+		siginfo_t info;
+
+		ret = sys_read(args->signal_img_fd, &info, sizeof(info));
+		if (ret == 0)
+			break;
+		if (ret < 0) {
+			pr_err("read() failed with code %d\n", ret);
+			return -1;
+		}
+		ret = sys_rt_sigqueueinfo(sys_getpid(), info.si_signo, &info);
+		if (ret) {
+			pr_err("Unable to send siginfo %d %x with code %d\n",
+					info.si_signo, info.si_code, ret);
+			return -1;;
+		}
+	}
+
+	sys_close(args->signal_img_fd);
+
+	return 0;
+}
 /*
  * The main routine to restore task via sigreturn.
  * This one is very special, we never return there
@@ -752,6 +786,12 @@ long __export_restore_task(struct task_restore_core_args *args)
 
 	sys_sigaction(SIGCHLD, &args->sigchld_act, NULL, sizeof(rt_sigset_t));
 
+	if (args->signal_img_fd >= 0) {
+		ret = restore_signals(args);
+		if (ret)
+			goto core_restore_end;
+	}
+
 	futex_set_and_wake(&thread_inprogress, args->nr_threads);
 
 	futex_dec_and_wake(&args->task_entries->nr_in_progress);
@@ -807,6 +847,7 @@ long __export_restore_task(struct task_restore_core_args *args)
 		: "rax","rsp","memory");
 
 core_restore_end:
+	futex_abort_and_wake(&task_entries->nr_in_progress);
 	pr_err("Restorer fail %ld\n", sys_getpid());
 	sys_exit_group(1);
 	return -1;
-- 
1.7.11.7