uevent: Fix netlink error while assigning pid in netlink client

unix.SockaddrNetlink represents a netlink client with the Pid being the netlink socket address. This can be assigned the actual pid of the process, but in case we have two netlink sockets opened at the same time, this results in errors in binding to the netlink socket. Assign this to zero which means the kernel takes care of assigning it. See http://man7.org/linux/man-pages/man7/netlink.7.html Fixes #216 Signed-off-by: Archana Shinde <[email protected]>
kata-containers · Apr 23, 2018 · 8f828bb · 8f828bb
1 parent bdc70d4
commit 8f828bb
Showing 1 changed file with 3 additions and 2 deletions.
diff --git a/pkg/uevent/uevent.go b/pkg/uevent/uevent.go
@@ -9,7 +9,6 @@ package uevent
 import (
 	"bufio"
 	"io"
-	"os"
 	"strings"
 
 	"golang.org/x/sys/unix"
@@ -35,7 +34,9 @@ type ReaderCloser struct {
 func NewReaderCloser() (io.ReadCloser, error) {
 	nl := unix.SockaddrNetlink{
 		Family: unix.AF_NETLINK,
-		Pid:    uint32(os.Getpid()),
+		// Passing Pid as 0 here allows the kernel to take care of assigning
+		// it. This allows multiple netlink sockets to be used.
+		Pid:    uint32(0),
 		Groups: 1,
 	}