Bump github.com/weaveworks/tcptracer-bpf/ and github.com/iovisor/gobpf/

vendor/github.com/iovisor/gobpf/bpffs/COPYRIGHT.txt

@@ -0,0 +1,14 @@
+Copyright 2016 PLUMgrid
+Copyright 2016 Kinvolk
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.

vendor/github.com/iovisor/gobpf/bpffs/LICENSE.txt

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
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+
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+   you may not use this file except in compliance with the License.
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+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/github.com/iovisor/gobpf/bpffs/fs.go

@@ -0,0 +1,44 @@
+package bpffs
+
+import (
+	"fmt"
+	"syscall"
+	"unsafe"
+)
+
+const BPFFSPath = "/sys/fs/bpf"
+
+var FsMagicBPFFS int32
+
+func init() {
+	// https://github.com/coreutils/coreutils/blob/v8.27/src/stat.c#L275
+	// https://github.com/torvalds/linux/blob/v4.8/include/uapi/linux/magic.h#L80
+	magic := uint32(0xCAFE4A11)
+	// 0xCAFE4A11 overflows an int32, which is what's expected by Statfs_t.Type in 32bit platforms.
+	// To avoid conditional compilation for all 32bit/64bit platforms, we use an unsafe cast
+	FsMagicBPFFS = *(*int32)(unsafe.Pointer(&magic))
+}
+
+// IsMounted checks if the BPF fs is mounted already
+func IsMounted() (bool, error) {
+	var data syscall.Statfs_t
+	if err := syscall.Statfs(BPFFSPath, &data); err != nil {
+		return false, fmt.Errorf("cannot statfs %q: %v", BPFFSPath, err)
+	}
+	return int32(data.Type) == FsMagicBPFFS, nil
+}
+
+// Mount mounts the BPF fs if not already mounted
+func Mount() error {
+	mounted, err := IsMounted()
+	if err != nil {
+		return err
+	}
+	if mounted {
+		return nil
+	}
+	if err := syscall.Mount(BPFFSPath, BPFFSPath, "bpf", 0, ""); err != nil {
+		return fmt.Errorf("error mounting %q: %v", BPFFSPath, err)
+	}
+	return nil
+}

vendor/github.com/iovisor/gobpf/elf/elf.go

@@ -26,13 +26,18 @@ import (
 	"fmt"
 	"io"
 	"os"
+	"path/filepath"
 	"strings"
 	"syscall"
 	"unsafe"
+
+	"github.com/iovisor/gobpf/bpffs"
 )
 
 /*
+#define _GNU_SOURCE
 #include <sys/types.h>
+#include <sys/stat.h>
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -51,11 +56,16 @@ import (
 // from https://github.com/safchain/goebpf
 // Apache License, Version 2.0
 
+#define BUF_SIZE_MAP_NS 256
+
 typedef struct bpf_map_def {
   unsigned int type;
   unsigned int key_size;
   unsigned int value_size;
   unsigned int max_entries;
+  unsigned int map_flags;
+  unsigned int pinning;
+  char namespace[BUF_SIZE_MAP_NS];
 } bpf_map_def;
 
 typedef struct bpf_map {
@@ -63,6 +73,8 @@ typedef struct bpf_map {
 	bpf_map_def def;
 } bpf_map;
 
+extern int bpf_pin_object(int fd, const char *pathname);
+
 __u64 ptr_to_u64(void *ptr)
 {
 	return (__u64) (unsigned long) ptr;
@@ -113,9 +125,25 @@ static int bpf_create_map(enum bpf_map_type map_type, int key_size,
 	return ret;
 }
 
-static bpf_map *bpf_load_map(bpf_map_def *map_def)
+void create_bpf_obj_get(const char *pathname, void *attr)
+{
+	union bpf_attr *ptr_bpf_attr;
+	ptr_bpf_attr = (union bpf_attr *)attr;
+	ptr_bpf_attr->pathname = ptr_to_u64((void *) pathname);
+}
+
+int get_pinned_obj_fd(const char *path)
+{
+	union bpf_attr attr = {};
+	create_bpf_obj_get(path, &attr);
+	return syscall(__NR_bpf, BPF_OBJ_GET, &attr, sizeof(attr));
+}
+
+static bpf_map *bpf_load_map(bpf_map_def *map_def, const char *path)
 {
 	bpf_map *map;
+	struct stat st;
+	int ret, do_pin = 0;
 
 	map = calloc(1, sizeof(bpf_map));
 	if (map == NULL)
@@ -123,14 +151,38 @@ static bpf_map *bpf_load_map(bpf_map_def *map_def)
 
 	memcpy(&map->def, map_def, sizeof(bpf_map_def));
 
+	switch (map_def->pinning) {
+	case 1: // PIN_OBJECT_NS
+		// TODO to be implemented
+		return 0;
+	case 2: // PIN_GLOBAL_NS
+		if (stat(path, &st) == 0) {
+			ret = get_pinned_obj_fd(path);
+			if (ret < 0) {
+				return 0;
+			}
+			map->fd = ret;
+			return map;
+		}
+		do_pin = 1;
+	}
+
 	map->fd = bpf_create_map(map_def->type,
 		map_def->key_size,
 		map_def->value_size,
 		map_def->max_entries
 	);
 
-	if (map->fd < 0)
+	if (map->fd < 0) {
 		return 0;
+	}
+
+	if (do_pin) {
+		ret = bpf_pin_object(map->fd, path);
+		if (ret < 0) {
+			return 0;
+		}
+	}
 
 	return map;
 }
@@ -203,8 +255,8 @@ static int perf_event_open_map(int pid, int cpu, int group_fd, unsigned long fla
 	attr.size = sizeof(struct perf_event_attr);
 	attr.config = 10; // PERF_COUNT_SW_BPF_OUTPUT
 
-       return syscall(__NR_perf_event_open, &attr, pid, cpu,
-                      group_fd, flags);
+	return syscall(__NR_perf_event_open, &attr, pid, cpu,
+		       group_fd, flags);
 }
 */
 import "C"
@@ -243,40 +295,78 @@ func elfReadVersion(file *elf.File) (uint32, error) {
 	return 0, nil
 }
 
+func prepareBPFFS(namespace, name string) (string, error) {
+	err := bpffs.Mount()
+	if err != nil {
+		return "", err
+	}
+	mapPath := filepath.Join(BPFFSPath, namespace, BPFDirGlobals, name)
+	err = os.MkdirAll(filepath.Dir(mapPath), syscall.S_IRWXU)
+	if err != nil {
+		return "", fmt.Errorf("error creating map directory %q: %v", filepath.Dir(mapPath), err)
+	}
+	return mapPath, nil
+}
+
+func validMapNamespace(namespaceRaw *C.char) (string, error) {
+	namespace := C.GoStringN(namespaceRaw, C.int(C.strnlen(namespaceRaw, C.BUF_SIZE_MAP_NS)))
+	if namespace == "" || namespace == "." || namespace == ".." {
+		return "", fmt.Errorf("namespace must not be %q", namespace)
+	}
+	if strings.Contains(namespace, "/") {
+		return "", fmt.Errorf("no '/' allowed in namespace")
+	}
+	return namespace, nil
+}
+
 func elfReadMaps(file *elf.File) (map[string]*Map, error) {
 	maps := make(map[string]*Map)
-	for sectionIdx, section := range file.Sections {
-		if strings.HasPrefix(section.Name, "maps/") {
-			data, err := section.Data()
+	for _, section := range file.Sections {
+		if !strings.HasPrefix(section.Name, "maps/") {
+			continue
+		}
+
+		data, err := section.Data()
+		if err != nil {
+			return nil, err
+		}
+		if len(data) != C.sizeof_struct_bpf_map_def {
+			return nil, fmt.Errorf("only one map with size %d allowed per section", C.sizeof_struct_bpf_map_def)
+		}
+
+		name := strings.TrimPrefix(section.Name, "maps/")
+
+		mapDef := (*C.bpf_map_def)(unsafe.Pointer(&data[0]))
+
+		var mapPathC *C.char
+		if mapDef.pinning > 0 {
+			namespace, err := validMapNamespace(&mapDef.namespace[0])
 			if err != nil {
 				return nil, err
 			}
-
-			name := strings.TrimPrefix(section.Name, "maps/")
-
-			mapCount := len(data) / C.sizeof_struct_bpf_map_def
-			for i := 0; i < mapCount; i++ {
-				pos := i * C.sizeof_struct_bpf_map_def
-				cm, err := C.bpf_load_map((*C.bpf_map_def)(unsafe.Pointer(&data[pos])))
-				if cm == nil {
-					return nil, fmt.Errorf("error while loading map %q: %v", section.Name, err)
-				}
-
-				m := &Map{
-					Name:       name,
-					SectionIdx: sectionIdx,
-					Idx:        i,
-					m:          cm,
-				}
-
-				if oldMap, ok := maps[name]; ok {
-					return nil, fmt.Errorf("duplicate map: %q (section %q) and %q (section %q)",
-						oldMap.Name, file.Sections[oldMap.SectionIdx].Name,
-						name, section.Name)
-				}
-				maps[name] = m
+			mapPath, err := prepareBPFFS(namespace, name)
+			if err != nil {
+				return nil, fmt.Errorf("error preparing bpf fs: %v", err)
 			}
+			mapPathC = C.CString(mapPath)
+			defer C.free(unsafe.Pointer(mapPathC))
+		} else {
+			mapPathC = nil
 		}
+
+		cm, err := C.bpf_load_map(mapDef, mapPathC)
+		if cm == nil {
+			return nil, fmt.Errorf("error while loading map %q: %v", section.Name, err)
+		}
+
+		if oldMap, ok := maps[name]; ok {
+			return nil, fmt.Errorf("duplicate map: %q and %q", oldMap.Name, name)
+		}
+		maps[name] = &Map{
+			Name: name,
+			m:    cm,
+		}
+
 	}
 	return maps, nil
 }
@@ -598,7 +688,7 @@ func (b *Module) initializePerfMaps(parameters map[string]SectionParams) error {
 				return fmt.Errorf("error enabling perf event: %v", err2)
 			}
 
-			// assign perf fd tp map
+			// assign perf fd to map
 			ret, err := C.bpf_update_element(C.int(b.maps[name].m.fd), unsafe.Pointer(&cpu), unsafe.Pointer(&pmuFD), C.BPF_ANY)
 			if ret != 0 {
 				return fmt.Errorf("cannot assign perf fd to map %q: %v (cpu %d)", name, err, cpu)
@@ -617,10 +707,8 @@ func (b *Module) initializePerfMaps(parameters map[string]SectionParams) error {
 // Map represents a eBPF map. An eBPF map has to be declared in the
 // C file.
 type Map struct {
-	Name       string
-	SectionIdx int
-	Idx        int
-	m          *C.bpf_map
+	Name string
+	m    *C.bpf_map
 
 	// only for perf maps
 	pmuFDs    []C.int
@@ -642,3 +730,7 @@ func (b *Module) IterMaps() <-chan *Map {
 func (b *Module) Map(name string) *Map {
 	return b.maps[name]
 }
+
+func (m *Map) Fd() int {
+	return int(m.m.fd)
+}

vendor/github.com/iovisor/gobpf/elf/module.go

@@ -25,14 +25,17 @@ import (
 	"io"
 	"io/ioutil"
 	"os"
+	"path/filepath"
 	"strconv"
 	"strings"
 	"syscall"
+	"unsafe"
 )
 
 /*
 #include <unistd.h>
 #include <strings.h>
+#include <stdlib.h>
 #include "include/bpf.h"
 #include <linux/perf_event.h>
 #include <linux/unistd.h>
@@ -124,14 +127,13 @@ func writeKprobeEvent(probeType, eventName, funcName, maxactiveStr string) (int,
 	kprobeEventsFileName := "/sys/kernel/debug/tracing/kprobe_events"
 	f, err := os.OpenFile(kprobeEventsFileName, os.O_APPEND|os.O_WRONLY, 0666)
 	if err != nil {
-		return -1, fmt.Errorf("cannot open kprobe_events: %v\n", err)
+		return -1, fmt.Errorf("cannot open kprobe_events: %v", err)
 	}
 	defer f.Close()
 
 	cmd := fmt.Sprintf("%s%s:%s %s\n", probeType, maxactiveStr, eventName, funcName)
-	_, err = f.WriteString(cmd)
-	if err != nil {
-		return -1, fmt.Errorf("cannot write %q to kprobe_events: %v\n", cmd, err)
+	if _, err = f.WriteString(cmd); err != nil {
+		return -1, fmt.Errorf("cannot write %q to kprobe_events: %v", cmd, err)
 	}
 
 	kprobeIdFile := fmt.Sprintf("/sys/kernel/debug/tracing/events/kprobes/%s/id", eventName)
@@ -140,12 +142,12 @@ func writeKprobeEvent(probeType, eventName, funcName, maxactiveStr string) (int,
 		if os.IsNotExist(err) {
 			return -1, kprobeIDNotExist
 		}
-		return -1, fmt.Errorf("cannot read kprobe id: %v\n", err)
+		return -1, fmt.Errorf("cannot read kprobe id: %v", err)
 	}
 
 	kprobeId, err := strconv.Atoi(strings.TrimSpace(string(kprobeIdBytes)))
 	if err != nil {
-		return -1, fmt.Errorf("invalid kprobe id: %v\n", err)
+		return -1, fmt.Errorf("invalid kprobe id: %v", err)
 	}
 
 	return kprobeId, nil
@@ -257,8 +259,115 @@ func (b *Module) AttachCgroupProgram(cgroupProg *CgroupProgram, cgroupPath strin
 	cgroupFd := C.int(f.Fd())
 	ret, err := C.bpf_prog_attach(progFd, cgroupFd, uint32(attachType))
 	if ret < 0 {
-		return fmt.Errorf("failed to attach prog to cgroup %q: %v\n", cgroupPath, err)
+		return fmt.Errorf("failed to attach prog to cgroup %q: %v", cgroupPath, err)
 	}
 
 	return nil
 }
+
+func (b *Module) Kprobe(name string) *Kprobe {
+	return b.probes[name]
+}
+
+func (kp *Kprobe) Fd() int {
+	return kp.fd
+}
+
+func disableKprobe(eventName string) error {
+	kprobeEventsFileName := "/sys/kernel/debug/tracing/kprobe_events"
+	f, err := os.OpenFile(kprobeEventsFileName, os.O_APPEND|os.O_WRONLY, 0)
+	if err != nil {
+		return fmt.Errorf("cannot open kprobe_events: %v", err)
+	}
+	defer f.Close()
+	cmd := fmt.Sprintf("-:%s\n", eventName)
+	if _, err = f.WriteString(cmd); err != nil {
+		pathErr, ok := err.(*os.PathError)
+		if ok && pathErr.Err == syscall.ENOENT {
+			// This can happen when for example two modules
+			// use the same elf object and both call `Close()`.
+			// The second will encounter the error as the
+			// probe already has been cleared by the first.
+			return nil
+		} else {
+			return fmt.Errorf("cannot write %q to kprobe_events: %v", cmd, err)
+		}
+	}
+	return nil
+}
+
+func (b *Module) closeProbes() error {
+	var funcName string
+	for _, probe := range b.probes {
+		if err := syscall.Close(probe.efd); err != nil {
+			return fmt.Errorf("error closing perf event fd: %v", err)
+		}
+		if err := syscall.Close(probe.fd); err != nil {
+			return fmt.Errorf("error closing probe fd: %v", err)
+		}
+		name := probe.Name
+		isKretprobe := strings.HasPrefix(name, "kretprobe/")
+		var err error
+		if isKretprobe {
+			funcName = strings.TrimPrefix(name, "kretprobe/")
+			err = disableKprobe("r" + funcName)
+		} else {
+			funcName = strings.TrimPrefix(name, "kprobe/")
+			err = disableKprobe("p" + funcName)
+		}
+		if err != nil {
+			return fmt.Errorf("error clearing probe: %v", err)
+		}
+	}
+	return nil
+}
+
+func (b *Module) closeCgroupPrograms() error {
+	for _, program := range b.cgroupPrograms {
+		if err := syscall.Close(program.fd); err != nil {
+			return fmt.Errorf("error closing cgroup program fd: %v", err)
+		}
+	}
+	return nil
+}
+
+func unpinMap(m *Map) error {
+	if m.m.def.pinning == 0 {
+		return nil
+	}
+	namespace := C.GoString(&m.m.def.namespace[0])
+	mapPath := filepath.Join(BPFFSPath, namespace, BPFDirGlobals, m.Name)
+	return syscall.Unlink(mapPath)
+}
+
+func (b *Module) closeMaps() error {
+	for _, m := range b.maps {
+		if m.m.def.pinning > 0 {
+			unpinMap(m)
+		}
+		for _, fd := range m.pmuFDs {
+			if err := syscall.Close(int(fd)); err != nil {
+				return fmt.Errorf("error closing perf event fd: %v", err)
+			}
+		}
+		if err := syscall.Close(int(m.m.fd)); err != nil {
+			return fmt.Errorf("error closing map fd: %v", err)
+		}
+		C.free(unsafe.Pointer(m.m))
+	}
+	return nil
+}
+
+// Close takes care of terminating all underlying BPF programs and structures
+func (b *Module) Close() error {
+	if err := b.closeMaps(); err != nil {
+		return err
+	}
+	if err := b.closeProbes(); err != nil {
+		return err
+	}
+	if err := b.closeCgroupPrograms(); err != nil {
+		return err
+	}
+	return nil
+}

vendor/github.com/iovisor/gobpf/elf/module_unsupported.go

@@ -40,6 +40,10 @@ func (b *Module) CgroupProgram(name string) *CgroupProgram {
 	return nil
 }
 
+func (b *Module) Kprobe(name string) *Kprobe {
+	return nil
+}
+
 func (b *Module) AttachProgram(cgroupProg *CgroupProgram, cgroupPath string, attachType AttachType) error {
 	return fmt.Errorf("not supported")
 }

vendor/github.com/iovisor/gobpf/elf/perf.go

@@ -173,6 +173,12 @@ func (pm *PerfMap) PollStart() {
 
 		harvestLoop:
 			for {
+				select {
+				case <-pm.pollStop:
+					return
+				default:
+				}
+
 				var harvestCount C.int
 				beforeHarvest := nowNanoseconds()
 				for cpu := 0; cpu < cpuCount; cpu++ {

vendor/github.com/iovisor/gobpf/elf/pinning.go

@@ -0,0 +1,69 @@
+// +build linux
+
+package elf
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"unsafe"
+
+	"github.com/iovisor/gobpf/bpffs"
+)
+
+/*
+#include <linux/unistd.h>
+#include <linux/bpf.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+extern __u64 ptr_to_u64(void *);
+
+int bpf_pin_object(int fd, const char *pathname)
+{
+	union bpf_attr attr = {};
+
+	attr.pathname = ptr_to_u64((void *)pathname);
+	attr.bpf_fd = fd;
+
+	return syscall(__NR_bpf, BPF_OBJ_PIN, &attr, sizeof(attr));
+}
+*/
+import "C"
+
+const (
+	BPFDirGlobals = "globals" // as in iproute2's BPF_DIR_GLOBALS
+	BPFFSPath     = "/sys/fs/bpf/"
+)
+
+func pinObject(fd int, namespace, object, name string) error {
+	mounted, err := bpffs.IsMounted()
+	if err != nil {
+		return fmt.Errorf("error checking if %q is mounted: %v", BPFFSPath, err)
+	}
+	if !mounted {
+		return fmt.Errorf("bpf fs not mounted at %q", BPFFSPath)
+	}
+	mapPath := filepath.Join(BPFFSPath, namespace, object, name)
+	err = os.MkdirAll(filepath.Dir(mapPath), 0755)
+	if err != nil {
+		return fmt.Errorf("error creating map directory %q: %v", filepath.Dir(mapPath), err)
+	}
+	err = os.RemoveAll(mapPath)
+	if err != nil {
+		return fmt.Errorf("error removing old map file %q: %v", mapPath, err)
+	}
+
+	mapPathC := C.CString(mapPath)
+	defer C.free(unsafe.Pointer(mapPathC))
+
+	ret, err := C.bpf_pin_object(C.int(fd), mapPathC)
+	if ret != 0 {
+		return fmt.Errorf("error pinning object to %q: %v", mapPath, err)
+	}
+	return nil
+}
+
+func PinObjectGlobal(fd int, namespace, name string) error {
+	return pinObject(fd, namespace, BPFDirGlobals, name)
+}

vendor/github.com/weaveworks/tcptracer-bpf/bpf_helpers.h

@@ -60,12 +60,16 @@ unsigned long long load_word(void *skb,
 /* a helper structure used by eBPF C program
  * to describe map attributes to elf_bpf loader
  */
+#define BUF_SIZE_MAP_NS 256
+
 struct bpf_map_def {
 	unsigned int type;
 	unsigned int key_size;
 	unsigned int value_size;
 	unsigned int max_entries;
 	unsigned int map_flags;
+	unsigned int pinning;
+	char namespace[BUF_SIZE_MAP_NS];
 };
 
 static int (*bpf_skb_store_bytes)(void *ctx, int off, void *from, int len, int flags) =

vendor/github.com/weaveworks/tcptracer-bpf/pkg/tracer/tracer.go

@@ -129,6 +129,7 @@ func (t *Tracer) Stop() {
 	close(t.stopChan)
 	t.perfMapIPV4.PollStop()
 	t.perfMapIPV6.PollStop()
+	t.m.Close()
 }
 
 func initialize(module *bpflib.Module, eventMapName string, eventChan chan []byte, lostChan chan uint64) (*bpflib.PerfMap, error) {

vendor/github.com/weaveworks/tcptracer-bpf/tcptracer-bpf.c

@@ -24,6 +24,8 @@ struct bpf_map_def SEC("maps/tcp_event_ipv4") tcp_event_ipv4 = {
 	.key_size = sizeof(int),
 	.value_size = sizeof(__u32),
 	.max_entries = 1024,
+	.pinning = 0,
+	.namespace = "",
 };
 
 /* This is a key/value store with the keys being the cpu number
@@ -34,6 +36,8 @@ struct bpf_map_def SEC("maps/tcp_event_ipv6") tcp_event_ipv6 = {
 	.key_size = sizeof(int),
 	.value_size = sizeof(__u32),
 	.max_entries = 1024,
+	.pinning = 0,
+	.namespace = "",
 };
 
 /* These maps are used to match the kprobe & kretprobe of connect */
@@ -46,6 +50,8 @@ struct bpf_map_def SEC("maps/connectsock_ipv4") connectsock_ipv4 = {
 	.key_size = sizeof(__u64),
 	.value_size = sizeof(void *),
 	.max_entries = 1024,
+	.pinning = 0,
+	.namespace = "",
 };
 
 /* This is a key/value store with the keys being a pid
@@ -56,6 +62,8 @@ struct bpf_map_def SEC("maps/connectsock_ipv6") connectsock_ipv6 = {
 	.key_size = sizeof(__u64),
 	.value_size = sizeof(void *),
 	.max_entries = 1024,
+	.pinning = 0,
+	.namespace = "",
 };
 
 /* This is a key/value store with the keys being an ipv4_tuple_t
@@ -66,6 +74,8 @@ struct bpf_map_def SEC("maps/tuplepid_ipv4") tuplepid_ipv4 = {
 	.key_size = sizeof(struct ipv4_tuple_t),
 	.value_size = sizeof(struct pid_comm_t),
 	.max_entries = 1024,
+	.pinning = 0,
+	.namespace = "",
 };
 
 /* This is a key/value store with the keys being an ipv6_tuple_t
@@ -76,6 +86,8 @@ struct bpf_map_def SEC("maps/tuplepid_ipv6") tuplepid_ipv6 = {
 	.key_size = sizeof(struct ipv6_tuple_t),
 	.value_size = sizeof(struct pid_comm_t),
 	.max_entries = 1024,
+	.pinning = 0,
+	.namespace = "",
 };
 
 /* This is a key/value store with the keys being a pid
@@ -86,6 +98,8 @@ struct bpf_map_def SEC("maps/fdinstall_ret") fdinstall_ret = {
 	.key_size = sizeof(__u64),
 	.value_size = sizeof(unsigned int),
 	.max_entries = 1024,
+	.pinning = 0,
+	.namespace = "",
 };
 
 /* This is a key/value store with the keys being a pid (tgid)
@@ -96,6 +110,8 @@ struct bpf_map_def SEC("maps/fdinstall_pids") fdinstall_pids = {
 	.key_size = sizeof(__u32),
 	.value_size = sizeof(__u32),
 	.max_entries = 1024,
+	.pinning = 0,
+	.namespace = "",
 };
 
 /* http://stackoverflow.com/questions/1001307/detecting-endianness-programmatically-in-a-c-program */
@@ -132,6 +148,8 @@ struct bpf_map_def SEC("maps/tcptracer_status") tcptracer_status = {
 	.key_size = sizeof(__u64),
 	.value_size = sizeof(struct tcptracer_status_t),
 	.max_entries = 1,
+	.pinning = 0,
+	.namespace = "",
 };
 
 __attribute__((always_inline))

vendor/manifest

@@ -1016,11 +1016,20 @@
 			"revision": "76626ae9c91c4f2a10f34cad8ce83ea42c93bb75",
 			"branch": "master"
 		},
+		{
+			"importpath": "github.com/iovisor/gobpf/bpffs",
+			"repository": "https://github.com/iovisor/gobpf",
+			"vcs": "git",
+			"revision": "aef06278f7e7142309a608d0e14e69cf94a5adae",
+			"branch": "master",
+			"path": "/bpffs",
+			"notests": true
+		},
 		{
 			"importpath": "github.com/iovisor/gobpf/elf",
 			"repository": "https://github.com/iovisor/gobpf",
 			"vcs": "git",
-			"revision": "23f7ee81c1cc244d16ddc8110c2ec8b8a09d0448",
+			"revision": "aef06278f7e7142309a608d0e14e69cf94a5adae",
 			"branch": "master",
 			"path": "/elf",
 			"notests": true
@@ -1462,7 +1471,7 @@
 			"importpath": "github.com/weaveworks/tcptracer-bpf",
 			"repository": "https://github.com/weaveworks/tcptracer-bpf",
 			"vcs": "git",
-			"revision": "783f088bbe3e91d4d23cf2f48072f80de2fd03fc",
+			"revision": "a616ebc6c5ac196af743e5dfc621a52fce030f87",
 			"branch": "master",
 			"notests": true
 		},