cbcvebase.
CVE-2025-38256
published 2025-07-09

CVE-2025-38256: In the Linux kernel, the following vulnerability has been resolved: io_uring/rsrc: fix folio unpinning syzbot complains about an unmapping failure: […

PriorityP418medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.14%
3.6th percentile
In the Linux kernel, the following vulnerability has been resolved: io_uring/rsrc: fix folio unpinning syzbot complains about an unmapping failure: [ 108.070381][ T14] kernel BUG at mm/gup.c:71! [ 108.070502][ T14] Internal error: Oops - BUG: 00000000f2000800 [#1] SMP [ 108.123672][ T14] Hardware name: QEMU KVM Virtual Machine, BIOS edk2-20250221-8.fc42 02/21/2025 [ 108.127458][ T14] Workqueue: iou_exit io_ring_exit_work [ 108.174205][ T14] Call trace: [ 108.175649][ T14] sanity_check_pinned_pages+0x7cc/0x7d0 (P) [ 108.178138][ T14] unpin_user_page+0x80/0x10c [ 108.180189][ T14] io_release_ubuf+0x84/0xf8 [ 108.182196][ T14] io_free_rsrc_node+0x250/0x57c [ 108.184345][ T14] io_rsrc_data_free+0x148/0x298 [ 108.186493][ T14] io_sqe_buffers_unregister+0x84/0xa0 [ 108.188991][ T14] io_ring_ctx_free+0x48/0x480 [ 108.191057][ T14] io_ring_exit_work+0x764/0x7d8 [ 108.193207][ T14] process_one_work+0x7e8/0x155c [ 108.195431][ T14] worker_thread+0x958/0xed8 [ 108.197561][ T14] kthread+0x5fc/0x75c [ 108.199362][ T14] ret_from_fork+0x10/0x20 We can pin a tail page of a folio, but then io_uring will try to unpin the head page of the folio. While it should be fine in terms of keeping the page actually alive, mm folks say it's wrong and triggers a debug warning. Use unpin_user_folio() instead of unpin_user_page*. [axboe: adapt to current tree, massage commit message]

Affected

10 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.12.37-1 (forky)linux 6.12.37-1 (forky)
linuxlinux
linuxlinux>= a8edbb424b1391b077407c75d8f5d2ede77aa70d < 53fd75f25b223878b5fff14932e3a22f42b54f7753fd75f25b223878b5fff14932e3a22f42b54f77
linuxlinux>= a8edbb424b1391b077407c75d8f5d2ede77aa70d < 11e7b7369e655e6131387b174218d7fa9557b3da11e7b7369e655e6131387b174218d7fa9557b3da
linuxlinux>= a8edbb424b1391b077407c75d8f5d2ede77aa70d < 5afb4bf9fc62d828647647ec31745083637132e45afb4bf9fc62d828647647ec31745083637132e4
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.12.37-16.12.37-1
linuxlinux_kernel>= 0 < 6.12.37-16.12.37-1
linuxlinux_kernel>= 6.12 < 6.12.366.12.36
linuxlinux_kernel>= 6.13 < 6.15.56.15.5

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.6MEDIUM
vendor_ubuntu5.6MEDIUM
vendor_debian5.5LOW
vendor_redhat5.5MEDIUM
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