Matthew Ahrens e59a377a8f filesystem_limit/snapshot_limit is incorrectly enforced against root
The filesystem_limit and snapshot_limit properties limit the number of
filesystems or snapshots that can be created below this dataset.
According to the manpage, "The limit is not enforced if the user is
allowed to change the limit."  Two types of users are allowed to change
the limit:

1. Those that have been delegated the `filesystem_limit` or
`snapshot_limit` permission, e.g. with
`zfs allow USER filesystem_limit DATASET`.  This works properly.

2. A user with elevated system privileges (e.g. root).  This does not
work - the root user will incorrectly get an error when trying to create
a snapshot/filesystem, if it exceeds the `_limit` property.

The problem is that `priv_policy_ns()` does not work if the `cred_t` is
not that of the current process.  This happens when
`dsl_enforce_ds_ss_limits()` is called in syncing context (as part of a
sync task's check func) to determine the permissions of the
corresponding user process.

This commit fixes the issue by passing the `task_struct` (typedef'ed as
a `proc_t`) to syncing context, and then using `has_capability()` to
determine if that process is privileged.  Note that we still need to
pass the `cred_t` to syncing context so that we can check if the user
was delegated this permission with `zfs allow`.

This problem only impacts Linux.  Wrappers are added to FreeBSD but it
continues to use `priv_check_cred()`, which works on arbitrary `cred_t`.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes #8226
Closes #10545
2020-07-11 17:18:02 -07:00
2020-06-26 14:20:02 -07:00
2020-07-03 11:05:50 -07:00
2020-07-10 14:26:00 -07:00
2020-06-24 18:20:18 -07:00
2020-06-26 14:20:02 -07:00
2020-04-14 11:36:28 -07:00
2017-11-13 09:18:18 -08:00
2018-05-29 16:00:33 -07:00
2019-04-30 10:58:45 -07:00
2020-07-10 14:26:00 -07:00
2020-06-09 21:24:09 -07:00
2018-05-29 16:00:33 -07:00
2020-04-09 09:16:46 -07:00
2018-09-18 12:03:47 -07:00
2018-05-29 16:00:33 -07:00
2020-06-03 19:46:31 -07:00
2020-03-16 10:46:03 -07:00

img

OpenZFS is an advanced file system and volume manager which was originally developed for Solaris and is now maintained by the OpenZFS community. This repository contains the code for running OpenZFS on Linux and FreeBSD.

codecov coverity

Official Resources

Installation

Full documentation for installing OpenZFS on your favorite Linux distribution can be found at the ZoL Site.

Contribute & Develop

We have a separate document with contribution guidelines.

We have a Code of Conduct.

Release

OpenZFS is released under a CDDL license. For more details see the NOTICE, LICENSE and COPYRIGHT files; UCRL-CODE-235197

Supported Kernels

  • The META file contains the officially recognized supported Linux kernel versions.
  • Supported FreeBSD versions are 12-STABLE and 13-CURRENT.
S
Description
No description provided
Readme 122 MiB
Languages
C 70.2%
Shell 19.9%
Assembly 5.1%
M4 1.9%
Python 1.6%
Other 1.3%