From 44152f6fb66da0ade1aa226f0b66ebbaa43d54b1 Mon Sep 17 00:00:00 2001
From: Sebastiaan van Stijn <[email protected]>
Date: Fri, 7 Jul 2023 14:54:04 +0200
Subject: [PATCH 478/483] daemon: daemon.prepareMountPoints(): fix panic if
 mount is not a volume

The daemon.lazyInitializeVolume() function only handles restoring Volumes
if a Driver is specified. The Container's MountPoints field may also
contain other kind of mounts (e.g., bind-mounts). Those were ignored, and
don't return an error; https://github.com/moby/moby/blob/1d9c8619cded4657af1529779c5771127e8ad0e7/daemon/volumes.go#L243-L252C2

However, the prepareMountPoints() assumed each MountPoint was a volume,
and logged an informational message about the volume being restored;
https://github.com/moby/moby/blob/1d9c8619cded4657af1529779c5771127e8ad0e7/daemon/mounts.go#L18-L25

This would panic if the MountPoint was not a volume;

    github.com/docker/docker/daemon.(*Daemon).prepareMountPoints(0xc00054b7b8?, 0xc0007c2500)
            /root/rpmbuild/BUILD/src/engine/.gopath/src/github.com/docker/docker/daemon/mounts.go:24 +0x1c0
    github.com/docker/docker/daemon.(*Daemon).restore.func5(0xc0007c2500, 0x0?)
            /root/rpmbuild/BUILD/src/engine/.gopath/src/github.com/docker/docker/daemon/daemon.go:552 +0x271
    created by github.com/docker/docker/daemon.(*Daemon).restore
            /root/rpmbuild/BUILD/src/engine/.gopath/src/github.com/docker/docker/daemon/daemon.go:530 +0x8d8
    panic: runtime error: invalid memory address or nil pointer dereference
    [signal SIGSEGV: segmentation violation code=0x1 addr=0x30 pc=0x564e9be4c7c0]

This issue was introduced in 647c2a6cdd86d79230df1bf690d0b6a2930d6db2

Signed-off-by: Sebastiaan van Stijn <[email protected]>
(cherry picked from commit a490248f4d19164d78d3ef4f91cf142c3aad1790)
Signed-off-by: Cory Snider <[email protected]>
---
 daemon/mounts.go                  |  4 ++++
 1 files changed, 4 insertions(+)

diff --git a/daemon/mounts.go b/daemon/mounts.go
index 424e375037..3c79b0d447 100644
--- a/daemon/mounts.go
+++ b/daemon/mounts.go
@@ -15,6 +15,10 @@ func (daemon *Daemon) prepareMountPoints(container *container.Container) error {
 		if err := daemon.lazyInitializeVolume(container.ID, config); err != nil {
 			return err
 		}
+		if config.Volume == nil {
+			// FIXME(thaJeztah): should we check for config.Type here as well? (i.e., skip bind-mounts etc)
+			continue
+		}
 	}
 	return nil
 }
--
2.32.0 (Apple Git-132)