From 09214f21da8e5805a4628d555324e0d2e8a8f4c3 Mon Sep 17 00:00:00 2001
From: Kir Kolyshkin <kolyshkin@gmail.com>
Date: Tue, 25 Jan 2022 15:30:49 -0800
Subject: [PATCH 1/2] list: getContainers: less indentation

Instead of a huge if {} block, use continue.

Best reviewed with --ignore-all-space.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
(cherry picked from commit 095929b15eb21bfedfbcd46600c6fd3d1ea9d1da)
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
---
 list.go | 85 +++++++++++++++++++++++++++++----------------------------
 1 file changed, 43 insertions(+), 42 deletions(-)

diff --git a/list.go b/list.go
index 3503dcd2f5e..bf6ce792e69 100644
--- a/list.go
+++ b/list.go
@@ -127,50 +127,51 @@ func getContainers(context *cli.Context) ([]containerState, error) {
 
 	var s []containerState
 	for _, item := range list {
-		if item.IsDir() {
-			st, err := os.Stat(filepath.Join(absRoot, item.Name()))
-			if err != nil {
-				fatal(err)
-			}
-			// This cast is safe on Linux.
-			uid := st.Sys().(*syscall.Stat_t).Uid
-			owner, err := user.LookupUid(int(uid))
-			if err != nil {
-				owner.Name = fmt.Sprintf("#%d", uid)
-			}
+		if !item.IsDir() {
+			continue
+		}
+		st, err := os.Stat(filepath.Join(absRoot, item.Name()))
+		if err != nil {
+			fatal(err)
+		}
+		// This cast is safe on Linux.
+		uid := st.Sys().(*syscall.Stat_t).Uid
+		owner, err := user.LookupUid(int(uid))
+		if err != nil {
+			owner.Name = fmt.Sprintf("#%d", uid)
+		}
 
-			container, err := factory.Load(item.Name())
-			if err != nil {
-				fmt.Fprintf(os.Stderr, "load container %s: %v\n", item.Name(), err)
-				continue
-			}
-			containerStatus, err := container.Status()
-			if err != nil {
-				fmt.Fprintf(os.Stderr, "status for %s: %v\n", item.Name(), err)
-				continue
-			}
-			state, err := container.State()
-			if err != nil {
-				fmt.Fprintf(os.Stderr, "state for %s: %v\n", item.Name(), err)
-				continue
-			}
-			pid := state.BaseState.InitProcessPid
-			if containerStatus == libcontainer.Stopped {
-				pid = 0
-			}
-			bundle, annotations := utils.Annotations(state.Config.Labels)
-			s = append(s, containerState{
-				Version:        state.BaseState.Config.Version,
-				ID:             state.BaseState.ID,
-				InitProcessPid: pid,
-				Status:         containerStatus.String(),
-				Bundle:         bundle,
-				Rootfs:         state.BaseState.Config.Rootfs,
-				Created:        state.BaseState.Created,
-				Annotations:    annotations,
-				Owner:          owner.Name,
-			})
+		container, err := factory.Load(item.Name())
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "load container %s: %v\n", item.Name(), err)
+			continue
+		}
+		containerStatus, err := container.Status()
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "status for %s: %v\n", item.Name(), err)
+			continue
+		}
+		state, err := container.State()
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "state for %s: %v\n", item.Name(), err)
+			continue
+		}
+		pid := state.BaseState.InitProcessPid
+		if containerStatus == libcontainer.Stopped {
+			pid = 0
 		}
+		bundle, annotations := utils.Annotations(state.Config.Labels)
+		s = append(s, containerState{
+			Version:        state.BaseState.Config.Version,
+			ID:             state.BaseState.ID,
+			InitProcessPid: pid,
+			Status:         containerStatus.String(),
+			Bundle:         bundle,
+			Rootfs:         state.BaseState.Config.Rootfs,
+			Created:        state.BaseState.Created,
+			Annotations:    annotations,
+			Owner:          owner.Name,
+		})
 	}
 	return s, nil
 }

From 986edbe60ff9f87be578a503a941ed7bb95f9206 Mon Sep 17 00:00:00 2001
From: Kir Kolyshkin <kolyshkin@gmail.com>
Date: Tue, 25 Jan 2022 15:33:25 -0800
Subject: [PATCH 2/2] list: use Info(), fix race with delete

Since commit 551629417 we can (and should) use Info() to get access to
file stat. Do this.

While going over directory entries, a parallel runc delete can remove
an entry, and with the current code it results in a fatal error (which
was not observed in practice, but looks quite possible). To fix,
add a special case to continue on ErrNotExist.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
(cherry picked from commit 1a3ee4966ce58abd243cb6aeb55fb561dca31a56)
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
---
 list.go | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/list.go b/list.go
index bf6ce792e69..3fb9917248f 100644
--- a/list.go
+++ b/list.go
@@ -130,8 +130,12 @@ func getContainers(context *cli.Context) ([]containerState, error) {
 		if !item.IsDir() {
 			continue
 		}
-		st, err := os.Stat(filepath.Join(absRoot, item.Name()))
+		st, err := item.Info()
 		if err != nil {
+			if errors.Is(err, os.ErrNotExist) {
+				// Possible race with runc delete.
+				continue
+			}
 			fatal(err)
 		}
 		// This cast is safe on Linux.