Bug 2297553 (CVE-2024-40969)

Summary: CVE-2024-40969 kernel: f2fs: don't set RO when shutting down f2fs
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: dfreiber, drow, jburrell, vkumar
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: kernel 6.6.36, kernel 6.9.7, kernel 6.10-rc1 Doc Type: If docs needed, set a value
Doc Text:
A f2fs vulnerability was found in the Linux Kernel involving a deadlock during shutdown due to a failure to check for errors from the thaw_super function. When attempting to freeze the block device and set the file system to read-only, the system hangs if the superblock is already read-only.
Story Points: ---
Clone Of: Environment:
Last Closed: Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2024-07-12 13:43:01 UTC
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);