CVE-2025-21908

MEDIUM EPSS 3.2%
Published Apr 1, 20251y ago · Modified Jun 17, 20261w ago
5.5 CVSS 3.1
Medium
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Published Apr 1, 2025 1y ago
Last Modified Jun 17, 2026 1w ago

Description

In the Linux kernel, the following vulnerability has been resolved: NFS: fix nfs_release_folio() to not deadlock via kcompactd writeback Add PF_KCOMPACTD flag and current_is_kcompactd() helper to check for it so nfs_release_folio() can skip calling nfs_wb_folio() from kcompactd. Otherwise NFS can deadlock waiting for kcompactd enduced writeback which recurses back to NFS (which triggers writeback to NFSD via NFS loopback mount on the same host, NFSD blocks waiting for XFS's call to __filemap_get_folio): 6070.550357] INFO: task kcompactd0:58 blocked for more than 4435 seconds. {--- [58] "kcompactd0" [<0>] folio_wait_bit+0xe8/0x200 [<0>] folio_wait_writeback+0x2b/0x80 [<0>] nfs_wb_folio+0x80/0x1b0 [nfs] [<0>] nfs_release_folio+0x68/0x130 [nfs] [<0>] split_huge_page_to_list_to_order+0x362/0x840 [<0>] migrate_pages_batch+0x43d/0xb90 [<0>] migrate_pages_sync+0x9a/0x240 [<0>] migrate_pages+0x93c/0x9f0 [<0>] compact_zone+0x8e2/0x1030 [<0>] compact_node+0xdb/0x120 [<0>] kcompactd+0x121/0x2e0 [<0>] kthread+0xcf/0x100 [<0>] ret_from_fork+0x31/0x40 [<0>] ret_from_fork_asm+0x1a/0x30 ---} [akpm@linux-foundation.org: fix build]

CVSS Details

Base Score
5.5
Exploitability
1.8
Impact
3.6
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
3.2% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-667

Affected Products 8

VendorProductVersionRange
linuxlinux_kernel*≥6.3  –  <6.6.83
linuxlinux_kernel*≥6.7  –  <6.12.19
linuxlinux_kernel*≥6.13  –  <6.13.7
linuxlinux_kernel6.14any
linuxlinux_kernel6.14any
linuxlinux_kernel6.14any
linuxlinux_kernel6.14any
linuxlinux_kernel6.14any

References 4

  • git.kernel.org https://git.kernel.org/stable/c/5ae31c54cff745832b9bd5b32e71f3d1b607cd1e
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/8253ff29edcb429a9a6c75710941c6a16a9a34b1
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/ab0727d6e2196682351c25c1dd112136f6991f11
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/ce6d9c1c2b5cc785016faa11b48b6cd317eb367e
    Patch

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/5ae31c54cff745832b9bd5b32e71f3d1b607cd1e
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/8253ff29edcb429a9a6c75710941c6a16a9a34b1
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/ab0727d6e2196682351c25c1dd112136f6991f11
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/ce6d9c1c2b5cc785016faa11b48b6cd317eb367e
    Patch