Raw.mount.options not accepted in block device mount of ext4 disk device

LXD
1

/dev/sda10 contains an existing ext4 filesystem not mounted in the host (to maintain isolation between host and container)

Trying to start an instance containing this disk device:

  sda10_block_mount:
    path: /top
    raw.mount.options: nosuid,nodev,noexec
    source: /dev/sda10
    type: disk

fails with this error message:

Error: Failed to start device "sda10_block_mount": Unable to mount "/proc/self/fd/32" at "/var/snap/lxd/common/lxd/devices/test-ext4-block-mount/disk.sda10_block_mount.top" with filesystem "ext4": invalid argument
Try `lxc info --show-log test-ext4-block-mount` for more info

If I edit the instance configuration to delete the raw.mount.options line, the mount works fine.

Any idea what Iā€™m doing wrong?

-------- Further details and instance config: --------

running lxd 5.0.1 from snap stable channel
both host and container running debian bullseye
lxd default storage pool is a dedicated zfs partition

$ lxc info --show-log test-ext4-block-mount
Name: test-ext4-block-mount
Status: STOPPED
Type: container
Architecture: x86_64
Created: 2023/01/17 21:29 CST

Log:

(no further output following Log: above)

$ lxc config show test-ext4-block-mount -e
architecture: x86_64
config:
  image.architecture: amd64
  image.description: Debian bullseye amd64 (20221104_05:24)
  image.name: debian-bullseye-amd64-default-20221104_05:24
  image.os: debian
  image.release: bullseye
  image.serial: "20221104_05:24"
  image.variant: default
  volatile.apply_template: copy
  volatile.base_image: 529880cbdb026ec961d93a90ec7d21137a3649f515e25dc8503fff30c565468c
  volatile.cloud-init.instance-id: 30643e42-a0d2-454f-8f55-62f019b24376
  volatile.eth0.hwaddr: 00:16:3e:dd:0e:be
  volatile.idmap.base: "0"
  volatile.idmap.current: '[{"Isuid":true,"Isgid":false,"Hostid":1000000,"Nsid":0,"Maprange":1000000000},{"Isuid":false,"Isgid":true,"Hostid":1000000,"Nsid":0,"Maprange":1000000000}]'
  volatile.idmap.next: '[{"Isuid":true,"Isgid":false,"Hostid":1000000,"Nsid":0,"Maprange":1000000000},{"Isuid":false,"Isgid":true,"Hostid":1000000,"Nsid":0,"Maprange":1000000000}]'
  volatile.last_state.idmap: '[{"Isuid":true,"Isgid":false,"Hostid":1000000,"Nsid":0,"Maprange":1000000000},{"Isuid":false,"Isgid":true,"Hostid":1000000,"Nsid":0,"Maprange":1000000000}]'
  volatile.uuid: ad8d0c83-f79c-4c70-849c-b5ac8b68d2ae
devices:
  eth0:
    name: eth0
    nictype: bridged
    parent: br0lower
    type: nic
  root:
    path: /
    pool: default
    type: disk
  sda10_block_mount:
    path: /top
    raw.mount.options: nosuid,nodev,noexec
    source: /dev/sda10
    type: disk
ephemeral: false
profiles:
- default
stateful: false
description: ""
2

Have you identified which of those raw mount options causes the error?

3

I have run 8 different test cases with this instance (test-ext4-block-mount with config shown in my original post).

In 6 of these test cases, I replaced the 'raw.mount.options` line in the original instance with one of the following lines, respectively:

raw.mount.options: nosuid
raw.mount.options: nodev
raw.mount.options: noexec
raw.mount.options: relatime
raw.mount.options: ro
raw.mount.options: rw

In each of these cases starting the instance failed with exactly the same error message shown in my original post

The the remaining 2 test cases, I replaced the 'raw.mount.options` line with one of the following lines, respectively:

readonly: "true"
readonly: "false"

In each of these last 2 cases, the instance started up fine, and the mount worked, as indicated by these respective lines from the output of findmnt run in the instance

/top                       /proc/self/fd/35       ext4       ro,relatime
/top                       /proc/self/fd/90       ext4       rw,relatime

In summary, the 'raw.mount.options` line does not seem to be accepted regardless of which option it specifies.

4

There are some automated tests for this option but only using the uid and gid mount options. Please can you open an issue on github. Thanks

5

Will do ā€“ thanks

1 Like
6

Issue opened on github:
https://github.com/lxc/lxd/issues/11303

1 Like