CVE-2023-53608: Linux Kernel

High severity, CVSS 7.8. EPSS: 0.1% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix potential UAF of struct nilfs_sc_info in nilfs_segctor_thread() The finalization of nilfs_segctor_thread() can race with nilfs_segctor_kill_thread() which terminates that thread, potentially causing a use-after-free BUG as KASAN detected. At the end of nilfs_segctor_thread(), it assigns NULL to "sc_task" member of "struct nilfs_sc_info" to indicate the thread has finished, and then notifies nilfs_segctor_kill_thread() of this using waitqueue "sc_wait_task" on the struct nilfs_sc_info. However, here, immediately after the NULL assignment to "sc_task", it is possible that nilfs_segctor_kill_thread() will detect it and return to continue the deallocation, freeing the nilfs_sc_info structure before the thread does the notification. This fixes the issue by protecting the NULL assignment to "sc_task" and its notification, with spinlock "sc_state_lock" of the struct nilfs_sc_info. Since nilfs_segctor_kill_thread() does a final check to see if "sc_task" is NULL with "sc_state_lock" locked, this can eliminate the race.

Affected products

• Linux Linux Kernel: from 2.6.30, before 4.14.313 (fixed in 4.14.313); from 4.15, before 4.19.281 (fixed in 4.19.281); from 4.20, before 5.4.241 (fixed in 5.4.241); from 5.5, before 5.10.178 (fixed in 5.10.178); from 5.11, before 5.15.107 (fixed in 5.15.107); from 5.16, before 6.1.24 (fixed in 6.1.24); …

Published 2025-10-04. Last modified 2026-08-04.