cbcvebase.
CVE-2025-21908
published 2025-04-01

CVE-2025-21908: 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…

PriorityP418medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.15%
4.4th percentile
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" [] folio_wait_bit+0xe8/0x200 [] folio_wait_writeback+0x2b/0x80 [] nfs_wb_folio+0x80/0x1b0 [nfs] [] nfs_release_folio+0x68/0x130 [nfs] [] split_huge_page_to_list_to_order+0x362/0x840 [] migrate_pages_batch+0x43d/0xb90 [] migrate_pages_sync+0x9a/0x240 [] migrate_pages+0x93c/0x9f0 [] compact_zone+0x8e2/0x1030 [] compact_node+0xdb/0x120 [] kcompactd+0x121/0x2e0 [] kthread+0xcf/0x100 [] ret_from_fork+0x31/0x40 [] ret_from_fork_asm+0x1a/0x30 ---} [[email protected]: fix build]

Affected

15 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.12.19-1 (forky)linux 6.12.19-1 (forky)
linuxlinux
linuxlinux>= 96780ca55e3cbf4f150fd5a833a61492c9947b5b < ab0727d6e2196682351c25c1dd112136f6991f11ab0727d6e2196682351c25c1dd112136f6991f11
linuxlinux>= 96780ca55e3cbf4f150fd5a833a61492c9947b5b < 5ae31c54cff745832b9bd5b32e71f3d1b607cd1e5ae31c54cff745832b9bd5b32e71f3d1b607cd1e
linuxlinux>= 96780ca55e3cbf4f150fd5a833a61492c9947b5b < 8253ff29edcb429a9a6c75710941c6a16a9a34b18253ff29edcb429a9a6c75710941c6a16a9a34b1
linuxlinux>= 96780ca55e3cbf4f150fd5a833a61492c9947b5b < ce6d9c1c2b5cc785016faa11b48b6cd317eb367ece6d9c1c2b5cc785016faa11b48b6cd317eb367e
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.12.19-16.12.19-1
linuxlinux_kernel>= 0 < 6.12.19-16.12.19-1
linuxlinux_kernel>= 0 < 6.8.0-84.846.8.0-84.84
linuxlinux_kernel>= 6.13 < 6.13.76.13.7
linuxlinux_kernel>= 6.3 < 6.6.836.6.83
linuxlinux_kernel>= 6.7 < 6.12.196.12.19
msrcazl3_kernel_6.6.82.1-1_on_azure_linux_3.0
msrcazl3_kernel_6.6.85.1-2_on_azure_linux_3.0

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.9MEDIUM
vendor_ubuntu5.9MEDIUM
vendor_debian5.5LOW
vendor_msrc5.5MEDIUM
vendor_redhat5.5MEDIUM
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