CVE-2022-49995

In the Linux kernel, the following vulnerability has been resolved: writeback: avoid use-after-free after removing device When a disk is removed, bdi_unregister gets called to stop further writeback and wait for associated delayed work to complete. However, wb_inode_writeback_end() may schedule bandwidth estimation dwork after this has completed, which can result in the timer attempting to access the just freed bdi_writeback. Fix this by checking if the bdi_writeback is alive, similar to when scheduling writeback work. Since this requires wb->work_lock, and wb_inode_writeback_end() may get called from interrupt, switch wb->work_lock to an irqsafe lock.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/9a6c710f3bc10bc9cc23e1c080b53245b7f9d5b7	Patch
https://git.kernel.org/stable/c/f87904c075515f3e1d8f4a7115869d3b914674fd	Patch
https://git.kernel.org/stable/c/f96b9f7c1676923bce871e728bb49c0dfa5013cc	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:6.0:rc1::::::
	cpe:2.3:o:linux:linux_kernel:6.0:rc2::::::

History

No history.

Information

Published : 2025-06-18 11:15

Updated : 2025-11-14 18:11

NVD link : CVE-2022-49995

Mitre link : CVE-2022-49995

CVE.ORG link : CVE-2022-49995

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-416

Use After Free

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