summaryrefslogtreecommitdiffhomepage
diff options
context:
space:
mode:
-rw-r--r--runsc/boot/loader.go30
1 files changed, 29 insertions, 1 deletions
diff --git a/runsc/boot/loader.go b/runsc/boot/loader.go
index e7ca98134..1ed46bdb9 100644
--- a/runsc/boot/loader.go
+++ b/runsc/boot/loader.go
@@ -175,6 +175,9 @@ type Args struct {
UserLogFD int
}
+// make sure stdioFDs are always the same on initial start and on restore
+const startingStdioFD = 64
+
// New initializes a new kernel loader configured by spec.
// New also handles setting up a kernel for restoring a container.
func New(args Args) (*Loader, error) {
@@ -319,6 +322,21 @@ func New(args Args) (*Loader, error) {
return nil, fmt.Errorf("creating pod mount hints: %v", err)
}
+ var stdioFDs []int
+ newfd := startingStdioFD
+ for _, fd := range args.StdioFDs {
+ err := syscall.Dup3(fd, newfd, syscall.O_CLOEXEC)
+ if err != nil {
+ return nil, fmt.Errorf("dup3 of stdioFDs failed: %v", err)
+ }
+ stdioFDs = append(stdioFDs, newfd)
+ err = syscall.Close(fd)
+ if err != nil {
+ return nil, fmt.Errorf("close original stdioFDs failed: %v", err)
+ }
+ newfd++
+ }
+
eid := execID{cid: args.ID}
l := &Loader{
k: k,
@@ -327,7 +345,7 @@ func New(args Args) (*Loader, error) {
watchdog: dog,
spec: args.Spec,
goferFDs: args.GoferFDs,
- stdioFDs: args.StdioFDs,
+ stdioFDs: stdioFDs,
rootProcArgs: procArgs,
sandboxID: args.ID,
processes: map[execID]*execProcess{eid: {}},
@@ -569,6 +587,16 @@ func (l *Loader) run() error {
}
})
+ // l.stdioFDs are derived from dup() in boot.New() and they are now dup()ed again
+ // either in createFDTable() during initial start or in descriptor.initAfterLoad()
+ // during restore, we can release l.stdioFDs now.
+ for _, fd := range l.stdioFDs {
+ err := syscall.Close(fd)
+ if err != nil {
+ return fmt.Errorf("close dup()ed stdioFDs: %v", err)
+ }
+ }
+
log.Infof("Process should have started...")
l.watchdog.Start()
return l.k.Start()