CVE-2025-21933

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

arm: pgtable: fix NULL pointer dereference issue

When update_mmu_cache_range() is called by update_mmu_cache(), the vmf

parameter is NULL, which will cause a NULL pointer dereference issue in

adjust_pte():

Unable to handle kernel NULL pointer dereference at virtual address 00000030 when read

Hardware name: Atmel AT91SAM9

PC is at update_mmu_cache_range+0x1e0/0x278

LR is at pte_offset_map_rw_nolock+0x18/0x2c

Call trace:

update_mmu_cache_range from remove_migration_pte+0x29c/0x2ec

remove_migration_pte from rmap_walk_file+0xcc/0x130

rmap_walk_file from remove_migration_ptes+0x90/0xa4

remove_migration_ptes from migrate_pages_batch+0x6d4/0x858

migrate_pages_batch from migrate_pages+0x188/0x488

migrate_pages from compact_zone+0x56c/0x954

compact_zone from compact_node+0x90/0xf0

compact_node from kcompactd+0x1d4/0x204

kcompactd from kthread+0x120/0x12c

kthread from ret_from_fork+0x14/0x38

Exception stack(0xc0d8bf

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References