CVE-2021-47254

gfs2: Fix use-after-free in gfs2_glock_shrink_scan

State: Published
Severity: 7.8 High
Published: May 21, 2024
Updated: Aug 5, 2026
Reserved: Apr 10, 2024

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.

Scores

CVSS	Score	Vector	Source
3.1	7.8 High	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H	Linux

Weaknesses

The record names no weakness.

Affected Products

Product	Versions
LinuxLinux	6948c6bc17d666663a84c124b3176039e64a58f4 to before 38ce329534500bf4ae71f81df6a37a406cf187b4Affected b568ed385a18c0ddbe41862b69088b636550a04f to before 92869945cc5b78ee8a1ef90336fe070893e3458aAffected 762bb3528249604bc680a9df635e8995740176de to before 0364742decb0f02bc183404868b82896f7992595Affected bac8520892812dada1ac93f27d96317470d24b1f to before 094bf5670e762afa243d2c41a5c4ab71c7447bf4Affected 7881ef3f33bb80f459ea6020d1e021fc524a6348 to before 86fd5b27db743a0ce0cc245e3a34813b2aa6ec1dAffected 7881ef3f33bb80f459ea6020d1e021fc524a6348 to before a61156314b66456ab6a291ed5deba1ebd002ab3cAffected 7881ef3f33bb80f459ea6020d1e021fc524a6348 to before e87ef30fe73e7e10d2c85bdcc778dcec24dca553Affected 7881ef3f33bb80f459ea6020d1e021fc524a6348 to before 1ab19c5de4c537ec0d9b21020395a5b5a6c059b2Affected 1e7a416fb765c9072479dc424780c0937ba99270Affected dcbdbe13796ffa561510d2686a6318564e728bbdAffected 4.4.181 to before 4.4.274Affected 4.9.180 to before 4.9.274Affected 4.14.123 to before 4.14.238Affected 4.19.47 to before 4.19.196Affected 5.0.20 to before 5.1Affected 5.1.6 to before 5.2Affected
LinuxLinux	5.2Affected before 5.2Not affected 4.4.274 through 4.4.Not affected 4.9.274 through 4.9.Not affected 4.14.238 through 4.14.Not affected 4.19.196 through 4.19.Not affected 5.4.127 through 5.4.Not affected 5.10.45 through 5.10.Not affected 5.12.12 through 5.12.*Not affected 5.13 and laterNot affected

Product

Versions

LinuxLinux

6948c6bc17d666663a84c124b3176039e64a58f4 to before 38ce329534500bf4ae71f81df6a37a406cf187b4Affected
b568ed385a18c0ddbe41862b69088b636550a04f to before 92869945cc5b78ee8a1ef90336fe070893e3458aAffected
762bb3528249604bc680a9df635e8995740176de to before 0364742decb0f02bc183404868b82896f7992595Affected
bac8520892812dada1ac93f27d96317470d24b1f to before 094bf5670e762afa243d2c41a5c4ab71c7447bf4Affected
7881ef3f33bb80f459ea6020d1e021fc524a6348 to before 86fd5b27db743a0ce0cc245e3a34813b2aa6ec1dAffected
7881ef3f33bb80f459ea6020d1e021fc524a6348 to before a61156314b66456ab6a291ed5deba1ebd002ab3cAffected
7881ef3f33bb80f459ea6020d1e021fc524a6348 to before e87ef30fe73e7e10d2c85bdcc778dcec24dca553Affected
7881ef3f33bb80f459ea6020d1e021fc524a6348 to before 1ab19c5de4c537ec0d9b21020395a5b5a6c059b2Affected
1e7a416fb765c9072479dc424780c0937ba99270Affected
dcbdbe13796ffa561510d2686a6318564e728bbdAffected
4.4.181 to before 4.4.274Affected
4.9.180 to before 4.9.274Affected
4.14.123 to before 4.14.238Affected
4.19.47 to before 4.19.196Affected
5.0.20 to before 5.1Affected
5.1.6 to before 5.2Affected

LinuxLinux

5.2Affected
before 5.2Not affected
4.4.274 through 4.4.*Not affected
4.9.274 through 4.9.*Not affected
4.14.238 through 4.14.*Not affected
4.19.196 through 4.19.*Not affected
5.4.127 through 5.4.*Not affected
5.10.45 through 5.10.*Not affected
5.12.12 through 5.12.*Not affected
5.13 and laterNot affected

References

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