Vulnerability CVE-2024-40969

Vulnerability CVE-2024-40969

Published: 2024-07-12

Description:

In the Linux kernel, the following vulnerability has been resolved:

f2fs: don't set RO when shutting down f2fs

Shutdown does not check the error of thaw_super due to readonly, which
causes a deadlock like below.

f2fs_ioc_shutdown(F2FS_GOING_DOWN_FULLSYNC) issue_discard_thread
- bdev_freeze
- freeze_super
- f2fs_stop_checkpoint()
- f2fs_handle_critical_error - sb_start_write
- set RO - waiting
- bdev_thaw
- thaw_super_locked
- return -EINVAL, if sb_rdonly()
- f2fs_stop_discard_thread
-> wait for kthread_stop(discard_thread);

References:

https://git.kernel.org/stable/c/1036d3ea7a32cb7cee00885c73a1f2ba7fbc499a

https://git.kernel.org/stable/c/f47ed3b284b38f235355e281f57dfa8fffcc6563

https://git.kernel.org/stable/c/3bdb7f161697e2d5123b89fe1778ef17a44858e7

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