Fix reading of network namespace inodes

probe/endpoint/procspy/proc.go

@@ -5,6 +5,7 @@ package procspy
 import (
 	"bytes"
 	"log"
+	"os"
 	"path/filepath"
 	"strconv"
 	"syscall"
@@ -30,7 +31,7 @@ func walkProcPid(buf *bytes.Buffer, walker process.Walker, namespaceTicker <-cha
 	var (
 		res        = map[uint64]*Proc{}              // map socket inode -> process
 		namespaces = map[uint64][]*process.Process{} // map network namespace id -> processes
-		statT      syscall.Stat_t
+
 	)
 
 	// Two process passes: One to group processes by namespace and another
@@ -43,16 +44,23 @@ func walkProcPid(buf *bytes.Buffer, walker process.Walker, namespaceTicker <-cha
 
 	walker.Walk(func(p, _ process.Process) {
 		dirName := strconv.Itoa(p.PID)
+		linkBody, err := os.Readlink(filepath.Join(procRoot, dirName, "/ns/net"))
+
+		// inode must contain a string with format 'net:[inode]'
+		if err != nil || len(linkBody) < 5 {
+			return
+		}
 
-		if err := fs.Lstat(filepath.Join(procRoot, dirName, "/ns/net"), &statT); err != nil {
+		nsInode, err := strconv.ParseUint(linkBody[5:len(linkBody)-1], 10, 64)
+		if err != nil {
 			return
 		}
 
-		procs, ok := namespaces[statT.Ino]
+		procs, ok := namespaces[nsInode]
 		if ok {
-			namespaces[statT.Ino] = append(procs, &p)
+			namespaces[nsInode] = append(procs, &p)
 		} else {
-			namespaces[statT.Ino] = []*process.Process{&p}
+			namespaces[nsInode] = []*process.Process{&p}
 		}
 	})
 
@@ -96,6 +104,7 @@ func walkProcPid(buf *bytes.Buffer, walker process.Walker, namespaceTicker <-cha
 			}
 			var proc *Proc
 			for _, fd := range fds {
+				var statT syscall.Stat_t
 				// Direct use of syscall.Stat() to save garbage.
 				err = fs.Stat(filepath.Join(fdBase, fd), &statT)
 				if err != nil {