7.8

CVE-2021-47254

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.
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
Linux ≫ Linux Kernel Version < 4.4.274
Linux ≫ Linux Kernel Version >= 4.5 < 4.9.274
Linux ≫ Linux Kernel Version >= 4.10 < 4.14.238
Linux ≫ Linux Kernel Version >= 4.15 < 4.19.196
Linux ≫ Linux Kernel Version >= 4.20 < 5.4.127
Linux ≫ Linux Kernel Version >= 5.5 < 5.10.45
Linux ≫ Linux Kernel Version >= 5.11 < 5.12.12
Linux ≫ Linux Kernel Version5.13 Updaterc1
Linux ≫ Linux Kernel Version5.13 Updaterc2
Linux ≫ Linux Kernel Version5.13 Updaterc3
Linux ≫ Linux Kernel Version5.13 Updaterc4
Zu dieser CVE wurde keine CISA KEV oder CERT.AT-Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.02% 0.027
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
nvd@nist.gov 7.8 1.8 5.9
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE-416 Use After Free

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.