|Date: (C)2012-07-03 (M)2015-12-16|
|CVSS Score: 4.9||Access Vector: LOCAL|
|Exploitability Subscore: 3.9||Access Complexity: LOW|
|Impact Subscore: 6.9||Authentication: NONE|
| ||Confidentiality: NONE|
| ||Integrity: NONE|
| ||Availability: COMPLETE|
The journal_unmap_buffer function in fs/jbd2/transaction.c in the Linux kernel before 3.3.1 does not properly handle the _Delay and _Unwritten buffer head states, which allows local users to cause a denial of service (system crash) by leveraging the presence of an ext4 filesystem that was mounted with a journal.