Add Linux namespace delegation support

This allows ZFS datasets to be delegated to a user/mount namespace
Within that namespace, only the delegated datasets are visible
Works very similarly to Zones/Jailes on other ZFS OSes

As a user:
```
 $ unshare -Um
 $ zfs list
no datasets available
 $ echo $$
1234
```

As root:
```
 # zfs list
NAME                            ZONED  MOUNTPOINT
containers                      off    /containers
containers/host                 off    /containers/host
containers/host/child           off    /containers/host/child
containers/host/child/gchild    off    /containers/host/child/gchild
containers/unpriv               on     /unpriv
containers/unpriv/child         on     /unpriv/child
containers/unpriv/child/gchild  on     /unpriv/child/gchild

 # zfs zone /proc/1234/ns/user containers/unpriv
```

Back to the user namespace:
```
 $ zfs list
NAME                             USED  AVAIL     REFER  MOUNTPOINT
containers                       129M  47.8G       24K  /containers
containers/unpriv                128M  47.8G       24K  /unpriv
containers/unpriv/child          128M  47.8G      128M  /unpriv/child
```

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Will Andrews <will.andrews@klarasystems.com>
Signed-off-by: Allan Jude <allan@klarasystems.com>
Signed-off-by: Mateusz Piotrowski <mateusz.piotrowski@klarasystems.com>
Co-authored-by: Allan Jude <allan@klarasystems.com>
Co-authored-by: Mateusz Piotrowski <mateusz.piotrowski@klarasystems.com>
Sponsored-by: Buddy <https://buddy.works>
Closes #12263
This commit is contained in:
Will Andrews
2021-02-21 10:19:43 -06:00
committed by Brian Behlendorf
parent a1aa8f14c8
commit 4ed5e25074
33 changed files with 1166 additions and 15 deletions
+1 -1
View File
@@ -1081,7 +1081,7 @@
</function-decl>
</abi-instr>
<abi-instr address-size='64' path='os/linux/zone.c' language='LANG_C99'>
<typedef-decl name='zoneid_t' type-id='95e97e5e' id='4da03624'/>
<typedef-decl name='zoneid_t' type-id='3502e3ff' id='4da03624'/>
<function-decl name='getzoneid' mangled-name='getzoneid' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='getzoneid'>
<return type-id='4da03624'/>
</function-decl>