| From bippy-1.2.0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@kernel.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2025-21931: hwpoison, memory_hotplug: lock folio before unmap hwpoisoned folio |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| hwpoison, memory_hotplug: lock folio before unmap hwpoisoned folio |
| |
| Commit b15c87263a69 ("hwpoison, memory_hotplug: allow hwpoisoned pages to |
| be offlined) add page poison checks in do_migrate_range in order to make |
| offline hwpoisoned page possible by introducing isolate_lru_page and |
| try_to_unmap for hwpoisoned page. However folio lock must be held before |
| calling try_to_unmap. Add it to fix this problem. |
| |
| Warning will be produced if folio is not locked during unmap: |
| |
| ------------[ cut here ]------------ |
| kernel BUG at ./include/linux/swapops.h:400! |
| Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP |
| Modules linked in: |
| CPU: 4 UID: 0 PID: 411 Comm: bash Tainted: G W 6.13.0-rc1-00016-g3c434c7ee82a-dirty #41 |
| Tainted: [W]=WARN |
| Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015 |
| pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) |
| pc : try_to_unmap_one+0xb08/0xd3c |
| lr : try_to_unmap_one+0x3dc/0xd3c |
| Call trace: |
| try_to_unmap_one+0xb08/0xd3c (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 |
| Code: f9407be0 b5fff320 d4210000 17ffff97 (d4210000) |
| ---[ end trace 0000000000000000 ]--- |
| |
| The Linux kernel CVE team has assigned CVE-2025-21931 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.0 with commit b15c87263a69272423771118c653e9a1d0672caa and fixed in 6.1.140 with commit 3926b572fd073491bde13ec42ee08ac1b337bf4d |
| Issue introduced in 5.0 with commit b15c87263a69272423771118c653e9a1d0672caa and fixed in 6.6.92 with commit 93df6da64b004f75d307ed08d3f0f1020280d339 |
| Issue introduced in 5.0 with commit b15c87263a69272423771118c653e9a1d0672caa and fixed in 6.12.19 with commit 576a2f4c437c19bec7d05d05b5990f178d2b0f40 |
| Issue introduced in 5.0 with commit b15c87263a69272423771118c653e9a1d0672caa and fixed in 6.13.7 with commit 629dfc6ba5431056701d4e44830f3409b989955a |
| Issue introduced in 5.0 with commit b15c87263a69272423771118c653e9a1d0672caa and fixed in 6.14 with commit af288a426c3e3552b62595c6138ec6371a17dbba |
| Issue introduced in 3.16.65 with commit 85ef35ab972b7484f41c3bb2bbc79de212e19129 |
| Issue introduced in 4.4.170 with commit 060853fdd434ce620dd1dd7619ede834bd33b9d0 |
| Issue introduced in 4.9.150 with commit cb1206e85df291fefde27401190329e26996c54c |
| Issue introduced in 4.14.93 with commit 2c25071bed4b1f9c4cfb10a7914847d7069794bf |
| Issue introduced in 4.19.15 with commit 2c87072a3bf9bbcd747618bb2ccc3cd0da181db6 |
| Issue introduced in 4.20.2 with commit a2b977e3d9e4298d28ebe5cfff9e0859b74a7ac7 |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2025-21931 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| mm/memory_hotplug.c |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| https://git.kernel.org/stable/c/3926b572fd073491bde13ec42ee08ac1b337bf4d |
| https://git.kernel.org/stable/c/93df6da64b004f75d307ed08d3f0f1020280d339 |
| https://git.kernel.org/stable/c/576a2f4c437c19bec7d05d05b5990f178d2b0f40 |
| https://git.kernel.org/stable/c/629dfc6ba5431056701d4e44830f3409b989955a |
| https://git.kernel.org/stable/c/af288a426c3e3552b62595c6138ec6371a17dbba |
