Tracker / CVE-2021-47254
CVE-2021-47254
High 7.8
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.
Affected products and versions
| linux | linux_kernel |
|---|---|
| linux | linux_kernel · 4.14.123 → 4.14.238 |
| linux | linux_kernel · 4.19.47 → 4.19.196 |
| linux | linux_kernel · 4.4.181 → 4.4.274 |
| linux | linux_kernel · 4.9.180 → 4.9.274 |
| linux | linux_kernel · 5.0.20 → 5.1 |
| linux | linux_kernel · 5.1.6 → 5.4.127 |
| linux | linux_kernel · 5.11 → 5.12.12 |
| linux | linux_kernel · 5.5 → 5.10.45 |
Analysis
This page is not indexable yet.Until it carries original analysis — what it actually exposes, how to check in two minutes whether a system was touched, what to do if it was — the page stays noindex. The database decides that, not the template.