Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: gfs2: Fix use-after-free in gfs2_glock_shrink_scan The GLF_LRU flag is checked under lru_lock in gfs2_glock_remove_from_lru() to remove the glock from the lru list in __gfs2_glock_put(). On the shrink scan path, the same flag is cleared under lru_lock but because of cond_resched_lock(&lru_lock) in gfs2_dispose_glock_lru(), progress on the put side can be made without deleting the glock from the lru list. Keep GLF_LRU across the race window opened by cond_resched_lock(&lru_lock) to ensure correct behavior on both sides - clear GLF_LRU after list_del under lru_lock.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux Kernel | >= 4.4.181, < 4.4.274 |
Related Weaknesses (CWE)
References
- https://git.kernel.org/stable/c/0364742decb0f02bc183404868b82896f7992595Patch
- https://git.kernel.org/stable/c/094bf5670e762afa243d2c41a5c4ab71c7447bf4Patch
- https://git.kernel.org/stable/c/1ab19c5de4c537ec0d9b21020395a5b5a6c059b2Patch
- https://git.kernel.org/stable/c/38ce329534500bf4ae71f81df6a37a406cf187b4Patch
- https://git.kernel.org/stable/c/86fd5b27db743a0ce0cc245e3a34813b2aa6ec1dPatch
- https://git.kernel.org/stable/c/92869945cc5b78ee8a1ef90336fe070893e3458aPatch
- https://git.kernel.org/stable/c/a61156314b66456ab6a291ed5deba1ebd002ab3cPatch
- https://git.kernel.org/stable/c/e87ef30fe73e7e10d2c85bdcc778dcec24dca553Patch
- https://git.kernel.org/stable/c/0364742decb0f02bc183404868b82896f7992595Patch
- https://git.kernel.org/stable/c/094bf5670e762afa243d2c41a5c4ab71c7447bf4Patch
- https://git.kernel.org/stable/c/1ab19c5de4c537ec0d9b21020395a5b5a6c059b2Patch
- https://git.kernel.org/stable/c/38ce329534500bf4ae71f81df6a37a406cf187b4Patch
- https://git.kernel.org/stable/c/86fd5b27db743a0ce0cc245e3a34813b2aa6ec1dPatch
- https://git.kernel.org/stable/c/92869945cc5b78ee8a1ef90336fe070893e3458aPatch
- https://git.kernel.org/stable/c/a61156314b66456ab6a291ed5deba1ebd002ab3cPatch
FAQ
What is CVE-2021-47254?
CVE-2021-47254 is a vulnerability with a CVSS score of 7.8 (HIGH). In the Linux kernel, the following vulnerability has been resolved: gfs2: Fix use-after-free in gfs2_glock_shrink_scan The GLF_LRU flag is checked under lru_lock in gfs2_glock_remove_from_lru() to r...
How severe is CVE-2021-47254?
CVE-2021-47254 has been rated HIGH with a CVSS base score of 7.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2021-47254?
Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel.