CVE-2021-47342 (GCVE-0-2021-47342)
Vulnerability from cvelistv5
Published
2024-05-21 14:35
Modified
2025-06-19 12:56
Severity ?
Summary
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>
References
Impacted products
Vendor Product Version
Linux Linux Version: 5e4f5138bd8522ebe231a137682d3857209a2c07
Version: eb7b40d9d3785f7a131fb0b1f89bb6efa46c1833
Version: 618f003199c6188e01472b03cdbba227f1dc5f24
Version: cecfdb9cf9a700d1037066173abac0617f6788df
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