CVE-2023-54021: Linux

EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: ext4: set goal start correctly in ext4_mb_normalize_request We need to set ac_g_ex to notify the goal start used in ext4_mb_find_by_goal. Set ac_g_ex instead of ac_f_ex in ext4_mb_normalize_request. Besides we should assure goal start is in range [first_data_block, blocks_count) as ext4_mb_initialize_context does. [ Added a check to make sure size is less than ar->pright; otherwise we could end up passing an underflowed value of ar->pright - size to ext4_get_group_no_and_offset(), which will trigger a BUG_ON later on. - TYT ]

Affected products

• Linux Linux: from 2.6.25, before 4.14.316 (fixed in 4.14.316); from 4.15, before 4.19.284 (fixed in 4.19.284); from 4.20, before 5.4.244 (fixed in 5.4.244); from 5.5, before 5.10.181 (fixed in 5.10.181); from 5.11, before 5.15.113 (fixed in 5.15.113); from 5.16, before 6.1.30 (fixed in 6.1.30); …

Published 2025-12-24. Last modified 2026-06-17.