Matthew Ahrens 018f26041d deadlock between spa_errlog_lock and dp_config_rwlock
There is a lock order inversion deadlock between `spa_errlog_lock` and
`dp_config_rwlock`:

A thread in `spa_delete_dataset_errlog()` is running from a sync task.
It is holding the `dp_config_rwlock` for writer (see
`dsl_sync_task_sync()`), and waiting for the `spa_errlog_lock`.

A thread in `dsl_pool_config_enter()` is holding the `spa_errlog_lock`
(see `spa_get_errlog_size()`) and waiting for the `dp_config_rwlock` (as
reader).

Note that this was introduced by #12812.

This commit address this by defining the lock ordering to be
dp_config_rwlock first, then spa_errlog_lock / spa_errlist_lock.
spa_get_errlog() and spa_get_errlog_size() can acquire the locks in this
order, and then process_error_block() and get_head_and_birth_txg() can
verify that the dp_config_rwlock is already held.

Additionally, a buffer overrun in `spa_get_errlog()` is corrected.  Many
code paths didn't check if `*count` got to zero, instead continuing to
overwrite past the beginning of the userspace buffer at `uaddr`.

Tested by having some errors in the pool (via `zinject -t data
/path/to/file`), one thread running `zpool iostat 0.001`, and another
thread runs `zfs destroy` (in a loop, although it hits the first time).
This reproduces the problem easily without the fix, and works with the
fix.

Reviewed-by: Mark Maybee <mark.maybee@delphix.com>
Reviewed-by: George Amanakis <gamanakis@gmail.com>
Reviewed-by: George Wilson <gwilson@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes #14239
Closes #14289
2022-12-22 11:48:49 -08:00
2022-12-22 11:34:28 -08:00
2022-12-15 10:14:32 -08:00
2022-11-29 09:27:22 -08:00
2022-10-28 09:49:20 -07:00
2022-12-22 11:34:28 -08:00
2020-06-09 21:24:09 -07:00
2018-05-29 16:00:33 -07:00
2022-10-26 14:55:12 -07:00
2020-08-26 21:44:41 -07:00
2018-05-29 16:00:33 -07:00
2022-01-06 16:25:01 -08:00
2021-04-02 16:33:40 -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 operating system can be found at the Getting Started Page.

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 any supported branches and releases starting from 12.2-RELEASE.
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%