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

jbd2: check 'jh->b_transaction' before removing it from checkpoint

Following process will corrupt ext4 image:
Step 1:
jbd2_journal_commit_transaction
__jbd2_journal_insert_checkpoint(jh, commit_transaction)
// Put jh into trans1->t_checkpoint_list
journal->j_checkpoint_transactions = commit_transaction
// Put trans1 into journal->j_checkpoint_transactions

Step 2:
do_get_write_access
test_clear_buffer_dirty(bh) // clear buffer dirty,set jbd dirty
__jbd2_journal_file_buffer(jh, transaction) // jh belongs to trans2

Step 3:
drop_cache
journal_shrink_one_cp_list
jbd2_journal_try_remove_checkpoint
if (!trylock_buffer(bh)) // lock bh, true
if (buffer_dirty(bh)) // buffer is not dirty
__jbd2_journal_remove_checkpoint(jh)
// remove jh from trans1->t_checkpoint_list

Step 4:
jbd2_log_do_checkpoint
trans1 = journal->j_checkpoint_transactions
// jh is not in trans1->t_checkpoint_list
jbd2_cleanup_journal_tail(journal) // trans1 is done

Step 5: Power cut, trans2 is not committed, jh is lost in next mounting.

Fix it by checking 'jh->b_transaction' before remove it from checkpoint.
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Wed, 01 Oct 2025 12:00:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: jbd2: check 'jh->b_transaction' before removing it from checkpoint Following process will corrupt ext4 image: Step 1: jbd2_journal_commit_transaction __jbd2_journal_insert_checkpoint(jh, commit_transaction) // Put jh into trans1->t_checkpoint_list journal->j_checkpoint_transactions = commit_transaction // Put trans1 into journal->j_checkpoint_transactions Step 2: do_get_write_access test_clear_buffer_dirty(bh) // clear buffer dirty,set jbd dirty __jbd2_journal_file_buffer(jh, transaction) // jh belongs to trans2 Step 3: drop_cache journal_shrink_one_cp_list jbd2_journal_try_remove_checkpoint if (!trylock_buffer(bh)) // lock bh, true if (buffer_dirty(bh)) // buffer is not dirty __jbd2_journal_remove_checkpoint(jh) // remove jh from trans1->t_checkpoint_list Step 4: jbd2_log_do_checkpoint trans1 = journal->j_checkpoint_transactions // jh is not in trans1->t_checkpoint_list jbd2_cleanup_journal_tail(journal) // trans1 is done Step 5: Power cut, trans2 is not committed, jh is lost in next mounting. Fix it by checking 'jh->b_transaction' before remove it from checkpoint.
Title jbd2: check 'jh->b_transaction' before removing it from checkpoint
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-10-01T11:46:11.862Z

Reserved: 2025-10-01T11:39:39.407Z

Link: CVE-2023-53526

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2025-10-01T12:15:57.177

Modified: 2025-10-01T12:15:57.177

Link: CVE-2023-53526

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.