CVE-2021-47342

In the Linux kernel, the following vulnerability has been resolved: ext4: fix possible UAF when remounting r/o a mmp-protected file system After commit 618f003199c6 ("ext4: fix memory leak in ext4_fill_super"), after the file system is remounted read-only, there is a race where the kmmpd thread can exit, causing sbi->s_mmp_tsk to point at freed memory, which the call to ext4_stop_mmpd() can trip over. Fix this by only allowing kmmpd() to exit when it is stopped via ext4_stop_mmpd(). Bug-Report-Link: <20210629143603.2166962-1-yebin10@huawei.com>

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/61bb4a1c417e5b95d9edb4f887f131de32e419cb	Patch
https://git.kernel.org/stable/c/7ed572cdf11081f8f9e07abd4bea56a3f2c4edbd	Patch
https://git.kernel.org/stable/c/b663890d854403e566169f7e90aed5cd6ff64f6b	Patch
https://git.kernel.org/stable/c/61bb4a1c417e5b95d9edb4f887f131de32e419cb	Patch
https://git.kernel.org/stable/c/7ed572cdf11081f8f9e07abd4bea56a3f2c4edbd	Patch
https://git.kernel.org/stable/c/b663890d854403e566169f7e90aed5cd6ff64f6b	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::

History

No history.

Information

Published : 2024-05-21 15:15

Updated : 2024-12-26 19:29

NVD link : CVE-2021-47342

Mitre link : CVE-2021-47342

CVE.ORG link : CVE-2021-47342

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-416

Use After Free

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