cbcvebase.
CVE-2025-40006
published 2025-10-20

CVE-2025-40006: In the Linux kernel, the following vulnerability has been resolved: mm/hugetlb: fix folio is still mapped when deleted Migration may be raced with fallocating…

PriorityP339high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.19%
8.7th percentile
In the Linux kernel, the following vulnerability has been resolved: mm/hugetlb: fix folio is still mapped when deleted Migration may be raced with fallocating hole. remove_inode_single_folio will unmap the folio if the folio is still mapped. However, it's called without folio lock. If the folio is migrated and the mapped pte has been converted to migration entry, folio_mapped() returns false, and won't unmap it. Due to extra refcount held by remove_inode_single_folio, migration fails, restores migration entry to normal pte, and the folio is mapped again. As a result, we triggered BUG in filemap_unaccount_folio. The log is as follows: BUG: Bad page cache in process hugetlb pfn:156c00 page: refcount:515 mapcount:0 mapping:0000000099fef6e1 index:0x0 pfn:0x156c00 head: order:9 mapcount:1 entire_mapcount:1 nr_pages_mapped:0 pincount:0 aops:hugetlbfs_aops ino:dcc dentry name(?):"my_hugepage_file" flags: 0x17ffffc00000c1(locked|waiters|head|node=0|zone=2|lastcpupid=0x1fffff) page_type: f4(hugetlb) page dumped because: still mapped when deleted CPU: 1 UID: 0 PID: 395 Comm: hugetlb Not tainted 6.17.0-rc5-00044-g7aac71907bde-dirty #484 NONE Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015 Call Trace: dump_stack_lvl+0x4f/0x70 filemap_unaccount_folio+0xc4/0x1c0 __filemap_remove_folio+0x38/0x1c0 filemap_remove_folio+0x41/0xd0 remove_inode_hugepages+0x142/0x250 hugetlbfs_fallocate+0x471/0x5a0 vfs_fallocate+0x149/0x380 Hold folio lock before checking if the folio is mapped to avold race with migration.

Affected

28 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.158-1 (bookworm)linux 6.1.158-1 (bookworm)
debianlinux-6.1< linux 6.1.158-1 (bookworm)linux 6.1.158-1 (bookworm)
linuxlinux
linuxlinux>= 4aae8d1c051ea00b456da6811bc36d1f69de5445 < bc1c9ce8aeff45318332035dbef9713fb9e982d7bc1c9ce8aeff45318332035dbef9713fb9e982d7
linuxlinux>= 4aae8d1c051ea00b456da6811bc36d1f69de5445 < 91f548e920fbf8be3f285bfa3fa045ae017e836d91f548e920fbf8be3f285bfa3fa045ae017e836d
linuxlinux>= 4aae8d1c051ea00b456da6811bc36d1f69de5445 < 3e851448078f5b01f6264915df3cfef75e323a123e851448078f5b01f6264915df3cfef75e323a12
linuxlinux>= 4aae8d1c051ea00b456da6811bc36d1f69de5445 < c1dc0524ab2cc3982d4e0d2bfac71a0cd4d65c39c1dc0524ab2cc3982d4e0d2bfac71a0cd4d65c39
linuxlinux>= 4aae8d1c051ea00b456da6811bc36d1f69de5445 < c9c2a51f91aea70e89b496cac360cd795a2b3c26c9c2a51f91aea70e89b496cac360cd795a2b3c26
linuxlinux>= 4aae8d1c051ea00b456da6811bc36d1f69de5445 < 910d7749346c4b0acdc6e4adfdc4a9984281a206910d7749346c4b0acdc6e4adfdc4a9984281a206
linuxlinux>= 4aae8d1c051ea00b456da6811bc36d1f69de5445 < 21ee79ce938127f88fe07e409c1817f477dbe7ea21ee79ce938127f88fe07e409c1817f477dbe7ea
linuxlinux>= 4aae8d1c051ea00b456da6811bc36d1f69de5445 < 7b7387650dcf2881fd8bb55bcf3c8bd6c9542dd77b7387650dcf2881fd8bb55bcf3c8bd6c9542dd7
linuxlinux_kernel>= 0 < 5.10.247-15.10.247-1
linuxlinux_kernel>= 0 < 6.1.158-16.1.158-1
linuxlinux_kernel>= 0 < 6.12.57-16.12.57-1
linuxlinux_kernel>= 0 < 6.16.10-16.16.10-1
linuxlinux_kernel>= 0 < 5.15.0-170.1805.15.0-170.180
linuxlinux_kernel>= 0 < 6.8.0-106.1066.8.0-106.106
linuxlinux_kernel>= 4.5.0 < 5.4.3005.4.300
linuxlinux_kernel>= 5.11.0 < 5.15.1945.15.194
linuxlinux_kernel>= 5.16.0 < 6.1.1556.1.155
linuxlinux_kernel>= 5.5.0 < 5.10.2455.10.245
linuxlinux_kernel>= 6.13.0 < 6.16.106.16.10
linuxlinux_kernel>= 6.2.0 < 6.6.1096.6.109
linuxlinux_kernel>= 6.7.0 < 6.12.506.12.50
ubuntulinux-azure-5.15

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_ubuntu7.8HIGH
vendor_redhat4.7MEDIUM
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