From 3d3a2b38b4c8c7ae5861c9341c999ab68829a9de Mon Sep 17 00:00:00 2001
From: lifubang <lifubang@acmcoder.com>
Date: Thu, 3 Aug 2023 08:44:00 +0800
Subject: [PATCH 1/2] fix some file mode bits missing when doing mount syscall

Signed-off-by: lifubang <lifubang@acmcoder.com>
(cherry picked from commit 6092a4b42dc0ab0df9aa55dbdb4e6db6c490e14d)
---
 libcontainer/mount_linux.go  | 18 ++++++++++++++++++
 libcontainer/rootfs_linux.go |  2 +-
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/libcontainer/mount_linux.go b/libcontainer/mount_linux.go
index 5f49de964..948b6c0b4 100644
--- a/libcontainer/mount_linux.go
+++ b/libcontainer/mount_linux.go
@@ -1,6 +1,7 @@
 package libcontainer
 
 import (
+	"io/fs"
 	"strconv"
 
 	"golang.org/x/sys/unix"
@@ -81,3 +82,20 @@ func unmount(target string, flags int) error {
 	}
 	return nil
 }
+
+// syscallMode returns the syscall-specific mode bits from Go's portable mode bits.
+// Copy from https://cs.opensource.google/go/go/+/refs/tags/go1.20.7:src/os/file_posix.go;l=61-75
+func syscallMode(i fs.FileMode) (o uint32) {
+	o |= uint32(i.Perm())
+	if i&fs.ModeSetuid != 0 {
+		o |= unix.S_ISUID
+	}
+	if i&fs.ModeSetgid != 0 {
+		o |= unix.S_ISGID
+	}
+	if i&fs.ModeSticky != 0 {
+		o |= unix.S_ISVTX
+	}
+	// No mapping for Go's ModeTemporary (plan9 only).
+	return
+}
diff --git a/libcontainer/rootfs_linux.go b/libcontainer/rootfs_linux.go
index 54520ad01..c701d6a2f 100644
--- a/libcontainer/rootfs_linux.go
+++ b/libcontainer/rootfs_linux.go
@@ -464,7 +464,7 @@ func mountToRootfs(m *configs.Mount, c *mountConfig) error {
 				return err
 			}
 		} else {
-			dt := fmt.Sprintf("mode=%04o", stat.Mode())
+			dt := fmt.Sprintf("mode=%04o", syscallMode(stat.Mode()))
 			if m.Data != "" {
 				dt = dt + "," + m.Data
 			}

From aaed58c87b4e0f0174c050803105f5a1139d2130 Mon Sep 17 00:00:00 2001
From: lifubang <lifubang@acmcoder.com>
Date: Thu, 3 Aug 2023 08:46:37 +0800
Subject: [PATCH 2/2] add a test case about missing stricky bit

Signed-off-by: lifubang <lifubang@acmcoder.com>
(cherry picked from commit 83137c6884a4838ae03baa8b7f311729cc93c285)
Signed-off-by: lifubang <lifubang@acmcoder.com>
---
 tests/integration/run.bats | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/tests/integration/run.bats b/tests/integration/run.bats
index d2eae2a08..e59ccb4a4 100644
--- a/tests/integration/run.bats
+++ b/tests/integration/run.bats
@@ -59,6 +59,22 @@ function teardown() {
 	[ "$status" -ne 0 ]
 }
 
+# https://github.com/opencontainers/runc/issues/3952
+@test "runc run with tmpfs" {
+	requires root
+
+	chmod 'a=rwx,ug+s,+t' rootfs/tmp # set all bits
+	mode=$(stat -c %A rootfs/tmp)
+
+	# shellcheck disable=SC2016
+	update_config '.process.args = ["sh", "-c", "stat -c %A /tmp"]'
+	update_config '.mounts += [{"destination": "/tmp", "type": "tmpfs", "source": "tmpfs", "options":["noexec","nosuid","nodev","rprivate"]}]'
+
+	runc run test_tmpfs
+	[ "$status" -eq 0 ]
+	[ "$output" = "$mode" ]
+}
+
 @test "runc run with tmpfs perms" {
 	# shellcheck disable=SC2016
 	update_config '.process.args = ["sh", "-c", "stat -c %a /tmp/test"]'