Fix warning: redundant if ...; err != nil check, just return error instead.

This warning is produced by golint.

PiperOrigin-RevId: 195833381
Change-Id: Idd6a7e57e3cfdf00819f2374b19fc113585dc1e1

pkg/bpf/decoder.go

@@ -161,10 +161,7 @@ func decodeAlu(inst linux.BPFInstruction, w *bytes.Buffer) error {
 	default:
 		return fmt.Errorf("invalid BPF ALU instruction: %v", inst)
 	}
-	if err := decodeSource(inst, w); err != nil {
-		return err
-	}
-	return nil
+	return decodeSource(inst, w)
 }
 
 func decodeSource(inst linux.BPFInstruction, w *bytes.Buffer) error {

pkg/compressio/compressio.go

@@ -184,10 +184,7 @@ func handleResult(r result, callback func(*chunk) error) error {
 	if r.err != nil {
 		return r.err
 	}
-	if err := callback(r.chunk); err != nil {
-		return err
-	}
-	return nil
+	return callback(r.chunk)
 }
 
 // schedule schedules the given buffers.

pkg/p9/local_server/local_server.go

@@ -246,11 +246,7 @@ func (l *local) Symlink(oldname string, newname string, _ p9.UID, _ p9.GID) (p9.
 //
 // Not properly implemented.
 func (l *local) Link(target p9.File, newname string) error {
-	if err := os.Link(target.(*local).path, path.Join(l.path, newname)); err != nil {
-		return err
-	}
-
-	return nil
+	return os.Link(target.(*local).path, path.Join(l.path, newname))
 }
 
 // Mknod implements p9.File.Mknod.

pkg/sentry/fs/fdpipe/pipe.go

@@ -90,10 +90,7 @@ func (p *pipeOperations) init() error {
 	if err := syscall.SetNonblock(p.file.FD(), true); err != nil {
 		return err
 	}
-	if err := fdnotifier.AddFD(int32(p.file.FD()), &p.Queue); err != nil {
-		return err
-	}
-	return nil
+	return fdnotifier.AddFD(int32(p.file.FD()), &p.Queue)
 }
 
 // EventRegister implements waiter.Waitable.EventRegister.

pkg/sentry/fs/host/fs_test.go

@@ -141,11 +141,7 @@ func createTestDirs(ctx context.Context, t *testing.T, m *fs.MountNamespace) err
 		return err
 	}
 
-	if err := symlinks.CreateLink(ctx, r, "/symlinks", "recursive"); err != nil {
-		return err
-	}
-
-	return nil
+	return symlinks.CreateLink(ctx, r, "/symlinks", "recursive")
 }
 
 // allPaths returns a slice of all paths of entries visible in the rootfs.

pkg/sentry/fs/host/socket.go

@@ -69,10 +69,7 @@ func (e *endpoint) init() error {
 	}
 
 	e.stype = unix.SockType(stype)
-	if err := fdnotifier.AddFD(int32(e.fd), &e.queue); err != nil {
-		return err
-	}
-	return nil
+	return fdnotifier.AddFD(int32(e.fd), &e.queue)
 }
 
 // newEndpoint creates a new host endpoint.

pkg/sentry/kernel/task_signals.go

@@ -127,10 +127,7 @@ func (t *Task) dequeueSignalLocked() *arch.SignalInfo {
 	if info := t.pendingSignals.dequeue(t.tr.SignalMask); info != nil {
 		return info
 	}
-	if info := t.tg.pendingSignals.dequeue(t.tr.SignalMask); info != nil {
-		return info
-	}
-	return nil
+	return t.tg.pendingSignals.dequeue(t.tr.SignalMask)
 }
 
 // TakeSignal returns a pending signal not blocked by mask. Signal handlers are
@@ -144,10 +141,7 @@ func (t *Task) TakeSignal(mask linux.SignalSet) *arch.SignalInfo {
 	if info := t.pendingSignals.dequeue(mask); info != nil {
 		return info
 	}
-	if info := t.tg.pendingSignals.dequeue(mask); info != nil {
-		return info
-	}
-	return nil
+	return t.tg.pendingSignals.dequeue(mask)
 }
 
 // discardSpecificLocked removes all instances of the given signal from all

pkg/sentry/syscalls/linux/sys_file.go

@@ -460,14 +460,11 @@ func accessAt(t *kernel.Task, dirFD kdefs.FD, addr usermem.Addr, resolve bool, m
 			creds:   creds,
 		}
 
-		if err := d.Inode.CheckPermission(ctx, fs.PermMask{
+		return d.Inode.CheckPermission(ctx, fs.PermMask{
 			Read:    mode&rOK != 0,
 			Write:   mode&wOK != 0,
 			Execute: mode&xOK != 0,
-		}); err != nil {
-			return err
-		}
-		return nil
+		})
 	})
 }
 

pkg/tcpip/stack/transport_demuxer.go

@@ -158,9 +158,5 @@ func (d *transportDemuxer) findEndpointLocked(eps *transportEndpoints, vv *buffe
 
 	// Try to find a match with only the local port.
 	nid.LocalAddress = ""
-	if ep := eps.endpoints[nid]; ep != nil {
-		return ep
-	}
-
-	return nil
+	return eps.endpoints[nid]
 }