CVE-2025-21907

Published Apr 1, 2025

Last updated a year ago

CVSS medium 5.5

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: mm: memory-failure: update ttu flag inside unmap_poisoned_folio Patch series "mm: memory_failure: unmap poisoned folio during migrate properly", v3. Fix two bugs during folio migration if the folio is poisoned. This patch (of 3): Commit 6da6b1d4a7df ("mm/hwpoison: convert TTU_IGNORE_HWPOISON to TTU_HWPOISON") introduce TTU_HWPOISON to replace TTU_IGNORE_HWPOISON in order to stop send SIGBUS signal when accessing an error page after a memory error on a clean folio. However during page migration, anon folio must be set with TTU_HWPOISON during unmap_*(). For pagecache we need some policy just like the one in hwpoison_user_mappings to set this flag. So move this policy from hwpoison_user_mappings to unmap_poisoned_folio to handle this warning properly. Warning will be produced during unamp poison folio with the following log: ------------[ cut here ]------------ WARNING: CPU: 1 PID: 365 at mm/rmap.c:1847 try_to_unmap_one+0x8fc/0xd3c Modules linked in: CPU: 1 UID: 0 PID: 365 Comm: bash Tainted: G W 6.13.0-rc1-00018-gacdb4bbda7ab #42 Tainted: [W]=WARN Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015 pstate: 20400005 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : try_to_unmap_one+0x8fc/0xd3c lr : try_to_unmap_one+0x3dc/0xd3c Call trace: try_to_unmap_one+0x8fc/0xd3c (P) try_to_unmap_one+0x3dc/0xd3c (L) rmap_walk_anon+0xdc/0x1f8 rmap_walk+0x3c/0x58 try_to_unmap+0x88/0x90 unmap_poisoned_folio+0x30/0xa8 do_migrate_range+0x4a0/0x568 offline_pages+0x5a4/0x670 memory_block_action+0x17c/0x374 memory_subsys_offline+0x3c/0x78 device_offline+0xa4/0xd0 state_store+0x8c/0xf0 dev_attr_store+0x18/0x2c sysfs_kf_write+0x44/0x54 kernfs_fop_write_iter+0x118/0x1a8 vfs_write+0x3a8/0x4bc ksys_write+0x6c/0xf8 __arm64_sys_write+0x1c/0x28 invoke_syscall+0x44/0x100 el0_svc_common.constprop.0+0x40/0xe0 do_el0_svc+0x1c/0x28 el0_svc+0x30/0xd0 el0t_64_sync_handler+0xc8/0xcc el0t_64_sync+0x198/0x19c ---[ end trace 0000000000000000 ]--- [mawupeng1@huawei.com: unmap_poisoned_folio(): remove shadowed local `mapping', per Miaohe]
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

nvd@nist.gov
NVD-CWE-noinfo

Social media

Hype score
Not currently trending

  1. ๐๐š๐ญ๐œ๐ก ๐“๐ฎ๐ž๐ฌ๐๐š๐ฒ ๐—ฆ๐—ฒ๐—ฝ๐˜๐—ฒ๐—บ๐—ฏ๐—ฒ๐—ฟ ๐Ÿ๐ŸŽ๐Ÿ๐Ÿ“ ๐‡๐ข๐ ๐ก๐ฅ๐ข๐ ๐ก๐ญ๐ฌ ๐˜๐จ๐ฎ ๐’๐ก๐จ๐ฎ๐ฅ๐๐งโ€™๐ญ ๐Œ๐ข๐ฌ๐ฌ โ–ช๏ธMicrosoft has addressed 81 vulnerabilities, two zero-days with

    @Action1corp

    12 Sept 2025

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  2. ๐—ง๐—ผ๐—ฑ๐—ฎ๐˜†'๐˜€ ๐—ฃ๐—ฎ๐˜๐—ฐ๐—ต ๐—ง๐˜‚๐—ฒ๐˜€๐—ฑ๐—ฎ๐˜† ๐—ผ๐˜ƒ๐—ฒ๐—ฟ๐˜ƒ๐—ถ๐—ฒ๐˜„: โ–ช๏ธ Microsoft has addressed 81 vulnerabilities, two zero-days with PoC (CVE-2025-55234 and CVE-2025-21907), 8 critical โ–ช๏ธ Third-party: actively exploited vulnerabi

    @Action1corp

    9 Sept 2025

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Configurations

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References

Sources include official advisories and independent security research.