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docker/bsc1055676-0001-daemon-oci-obey-CL_UNPRIVILEGED-for-user-namespaced-.patch
Aleksa Sarai 9c7edd7eef - Update to Docker v17.09.1_ce. Upstream changelog:
https://github.com/docker/docker-ce/releases/tag/v17.09.1-ce
- Removed patches (merged upstream):
  - bsc1045628-0001-devicemapper-remove-container-rootfs-mountPath-after.patch
  - bsc1066210-0001-vendor-update-to-github.com-vbatts-tar-split-v0.10.2.patch
  - bsc1066801-0001-oci-add-proc-scsi-to-masked-paths.patch
- Update to Docker v17.09.0_ce. Upstream changelog:
  https://github.com/docker/docker-ce/releases/tag/v17.09.0-ce
- Rebased patches:
  * bsc1021227-0001-pkg-devmapper-dynamically-load-dm_task_deferred_remo.patch
  * bsc1045628-0001-devicemapper-remove-container-rootfs-mountPath-after.patch
  * bsc1055676-0001-daemon-oci-obey-CL_UNPRIVILEGED-for-user-namespaced-.patch
  * secrets-0001-daemon-allow-directory-creation-in-run-secrets.patch
  * secrets-0002-SUSE-implement-SUSE-container-secrets.patch
- Removed patches (merged upstream):
  - bsc1064781-0001-Allow-to-override-build-date.patch

OBS-URL: https://build.opensuse.org/package/show/Virtualization:containers/docker?expand=0&rev=228
2017-12-19 03:42:51 +00:00

97 lines
3.4 KiB
Diff

From a24b98c0fc45d640b4eed8105033b313b8145e35 Mon Sep 17 00:00:00 2001
From: Aleksa Sarai <asarai@suse.de>
Date: Sun, 15 Oct 2017 17:06:20 +1100
Subject: [PATCH] daemon: oci: obey CL_UNPRIVILEGED for user namespaced daemon
When runc is bind-mounting a particular path "with options", it has to
do so by first creating a bind-mount and the modifying the options of
said bind-mount via remount. However, in a user namespace, there are
restrictions on which flags you can change with a remount (due to
CL_UNPRIVILEGED being set in this instance). Docker historically has
ignored this, and as a result, internal Docker mounts (such as secrets)
haven't worked with --userns-remap. Fix this by preserving
CL_UNPRIVILEGED mount flags when Docker is spawning containers with user
namespaces enabled.
SUSE-Bug: https://bugzilla.suse.com/show_bug.cgi?id=1055676
SUSE-Backport: https://github.com/moby/moby/pull/35205
Signed-off-by: Aleksa Sarai <asarai@suse.de>
---
daemon/oci_linux.go | 46 ++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 46 insertions(+)
diff --git a/daemon/oci_linux.go b/daemon/oci_linux.go
index 0f8a392c2621..89ac627ff090 100644
--- a/daemon/oci_linux.go
+++ b/daemon/oci_linux.go
@@ -26,6 +26,7 @@ import (
"github.com/opencontainers/runc/libcontainer/user"
specs "github.com/opencontainers/runtime-spec/specs-go"
"github.com/sirupsen/logrus"
+ "golang.org/x/sys/unix"
)
var (
@@ -469,6 +470,38 @@ func ensureSharedOrSlave(path string) error {
return nil
}
+// Get the set of mount flags that are set on the mount that contains the given
+// path and are locked by CL_UNPRIVILEGED. This is necessary to ensure that
+// bind-mounting "with options" will not fail with user namespaces, due to
+// kernel restrictions that require user namespace mounts to preserve
+// CL_UNPRIVILEGED locked flags.
+func getUnprivilegedMountFlags(path string) ([]string, error) {
+ var statfs unix.Statfs_t
+ if err := unix.Statfs(path, &statfs); err != nil {
+ return nil, err
+ }
+
+ // The set of keys come from https://github.com/torvalds/linux/blob/v4.13/fs/namespace.c#L1034-L1048.
+ unprivilegedFlags := map[uint64]string{
+ unix.MS_RDONLY: "ro",
+ unix.MS_NODEV: "nodev",
+ unix.MS_NOEXEC: "noexec",
+ unix.MS_NOSUID: "nosuid",
+ unix.MS_NOATIME: "noatime",
+ unix.MS_RELATIME: "relatime",
+ unix.MS_NODIRATIME: "nodiratime",
+ }
+
+ var flags []string
+ for mask, flag := range unprivilegedFlags {
+ if uint64(statfs.Flags)&mask == mask {
+ flags = append(flags, flag)
+ }
+ }
+
+ return flags, nil
+}
+
var (
mountPropagationMap = map[string]int{
"private": mount.PRIVATE,
@@ -575,6 +608,19 @@ func setMounts(daemon *Daemon, s *specs.Spec, c *container.Container, mounts []c
opts = append(opts, mountPropagationReverseMap[pFlag])
}
+ // If we are using user namespaces, then we must make sure that we
+ // don't drop any of the CL_UNPRIVILEGED "locked" flags of the source
+ // "mount" when we bind-mount. The reason for this is that at the point
+ // when runc sets up the root filesystem, it is already inside a user
+ // namespace, and thus cannot change any flags that are locked.
+ if daemon.configStore.RemappedRoot != "" {
+ unprivOpts, err := getUnprivilegedMountFlags(m.Source)
+ if err != nil {
+ return err
+ }
+ opts = append(opts, unprivOpts...)
+ }
+
mt.Options = opts
s.Mounts = append(s.Mounts, mt)
}
--
2.15.0