ghsa-rgc8-7q99-mqx9
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
mm/mempool: fix poisoning order>0 pages with HIGHMEM
The kernel test has reported:
BUG: unable to handle page fault for address: fffba000 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page pde = 03171067 pte = 00000000 Oops: Oops: 0002 [#1] CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Tainted: G T 6.18.0-rc2-00031-gec7f31b2a2d3 #1 NONE a1d066dfe789f54bc7645c7989957d2bdee593ca Tainted: [T]=RANDSTRUCT Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 EIP: memset (arch/x86/include/asm/string_32.h:168 arch/x86/lib/memcpy_32.c:17) Code: a5 8b 4d f4 83 e1 03 74 02 f3 a4 83 c4 04 5e 5f 5d 2e e9 73 41 01 00 90 90 90 3e 8d 74 26 00 55 89 e5 57 56 89 c6 89 d0 89 f7 aa 89 f0 5e 5f 5d 2e e9 53 41 01 00 cc cc cc 55 89 e5 53 57 56 EAX: 0000006b EBX: 00000015 ECX: 001fefff EDX: 0000006b ESI: fffb9000 EDI: fffba000 EBP: c611fbf0 ESP: c611fbe8 DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068 EFLAGS: 00010287 CR0: 80050033 CR2: fffba000 CR3: 0316e000 CR4: 00040690 Call Trace: poison_element (mm/mempool.c:83 mm/mempool.c:102) mempool_init_node (mm/mempool.c:142 mm/mempool.c:226) mempool_init_noprof (mm/mempool.c:250 (discriminator 1)) ? mempool_alloc_pages (mm/mempool.c:640) bio_integrity_initfn (block/bio-integrity.c:483 (discriminator 8)) ? mempool_alloc_pages (mm/mempool.c:640) do_one_initcall (init/main.c:1283)
Christoph found out this is due to the poisoning code not dealing properly with CONFIG_HIGHMEM because only the first page is mapped but then the whole potentially high-order page is accessed.
We could give up on HIGHMEM here, but it's straightforward to fix this with a loop that's mapping, poisoning or checking and unmapping individual pages.
{
"affected": [],
"aliases": [
"CVE-2025-68231"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-12-16T14:15:57Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/mempool: fix poisoning order\u003e0 pages with HIGHMEM\n\nThe kernel test has reported:\n\n BUG: unable to handle page fault for address: fffba000\n #PF: supervisor write access in kernel mode\n #PF: error_code(0x0002) - not-present page\n *pde = 03171067 *pte = 00000000\n Oops: Oops: 0002 [#1]\n CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Tainted: G T 6.18.0-rc2-00031-gec7f31b2a2d3 #1 NONE a1d066dfe789f54bc7645c7989957d2bdee593ca\n Tainted: [T]=RANDSTRUCT\n Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\n EIP: memset (arch/x86/include/asm/string_32.h:168 arch/x86/lib/memcpy_32.c:17)\n Code: a5 8b 4d f4 83 e1 03 74 02 f3 a4 83 c4 04 5e 5f 5d 2e e9 73 41 01 00 90 90 90 3e 8d 74 26 00 55 89 e5 57 56 89 c6 89 d0 89 f7 \u003cf3\u003e aa 89 f0 5e 5f 5d 2e e9 53 41 01 00 cc cc cc 55 89 e5 53 57 56\n EAX: 0000006b EBX: 00000015 ECX: 001fefff EDX: 0000006b\n ESI: fffb9000 EDI: fffba000 EBP: c611fbf0 ESP: c611fbe8\n DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068 EFLAGS: 00010287\n CR0: 80050033 CR2: fffba000 CR3: 0316e000 CR4: 00040690\n Call Trace:\n poison_element (mm/mempool.c:83 mm/mempool.c:102)\n mempool_init_node (mm/mempool.c:142 mm/mempool.c:226)\n mempool_init_noprof (mm/mempool.c:250 (discriminator 1))\n ? mempool_alloc_pages (mm/mempool.c:640)\n bio_integrity_initfn (block/bio-integrity.c:483 (discriminator 8))\n ? mempool_alloc_pages (mm/mempool.c:640)\n do_one_initcall (init/main.c:1283)\n\nChristoph found out this is due to the poisoning code not dealing\nproperly with CONFIG_HIGHMEM because only the first page is mapped but\nthen the whole potentially high-order page is accessed.\n\nWe could give up on HIGHMEM here, but it\u0027s straightforward to fix this\nwith a loop that\u0027s mapping, poisoning or checking and unmapping\nindividual pages.",
"id": "GHSA-rgc8-7q99-mqx9",
"modified": "2025-12-16T15:30:46Z",
"published": "2025-12-16T15:30:46Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-68231"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/19de79aaea33ee1ea058c8711b3b2b4a7e4decd4"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/6a13b56537e7b0d97f4bb74e8038ce471f9770d7"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/a79e49e1704367b635edad1479db23d7cf1fb71a"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/ea4131665107e66ece90e66bcec1a2f1246cbd41"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/ec33b59542d96830e3c89845ff833cf7b25ef172"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date |
|---|
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