ghsa-j4gx-6m2g-9p7c
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
arm64/mm: fix incorrect file_map_count for invalid pmd
The page table check trigger BUG_ON() unexpectedly when split hugepage:
------------[ cut here ]------------ kernel BUG at mm/page_table_check.c:119! Internal error: Oops - BUG: 00000000f2000800 [#1] SMP Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 7 PID: 210 Comm: transhuge-stres Not tainted 6.1.0-rc3+ #748 Hardware name: linux,dummy-virt (DT) pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : page_table_check_set.isra.0+0x398/0x468 lr : page_table_check_set.isra.0+0x1c0/0x468 [...] Call trace: page_table_check_set.isra.0+0x398/0x468 __page_table_check_pte_set+0x160/0x1c0 __split_huge_pmd_locked+0x900/0x1648 __split_huge_pmd+0x28c/0x3b8 unmap_page_range+0x428/0x858 unmap_single_vma+0xf4/0x1c8 zap_page_range+0x2b0/0x410 madvise_vma_behavior+0xc44/0xe78 do_madvise+0x280/0x698 __arm64_sys_madvise+0x90/0xe8 invoke_syscall.constprop.0+0xdc/0x1d8 do_el0_svc+0xf4/0x3f8 el0_svc+0x58/0x120 el0t_64_sync_handler+0xb8/0xc0 el0t_64_sync+0x19c/0x1a0 [...]
On arm64, pmd_leaf() will return true even if the pmd is invalid due to pmd_present_invalid() check. So in pmdp_invalidate() the file_map_count will not only decrease once but also increase once. Then in set_pte_at(), the file_map_count increase again, and so trigger BUG_ON() unexpectedly.
Add !pmd_present_invalid() check in pmd_user_accessible_page() to fix the problem.
{
"affected": [],
"aliases": [
"CVE-2022-48897"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-08-21T07:15:05Z",
"severity": "MODERATE"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\narm64/mm: fix incorrect file_map_count for invalid pmd\n\nThe page table check trigger BUG_ON() unexpectedly when split hugepage:\n\n ------------[ cut here ]------------\n kernel BUG at mm/page_table_check.c:119!\n Internal error: Oops - BUG: 00000000f2000800 [#1] SMP\n Dumping ftrace buffer:\n (ftrace buffer empty)\n Modules linked in:\n CPU: 7 PID: 210 Comm: transhuge-stres Not tainted 6.1.0-rc3+ #748\n Hardware name: linux,dummy-virt (DT)\n pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)\n pc : page_table_check_set.isra.0+0x398/0x468\n lr : page_table_check_set.isra.0+0x1c0/0x468\n[...]\n Call trace:\n page_table_check_set.isra.0+0x398/0x468\n __page_table_check_pte_set+0x160/0x1c0\n __split_huge_pmd_locked+0x900/0x1648\n __split_huge_pmd+0x28c/0x3b8\n unmap_page_range+0x428/0x858\n unmap_single_vma+0xf4/0x1c8\n zap_page_range+0x2b0/0x410\n madvise_vma_behavior+0xc44/0xe78\n do_madvise+0x280/0x698\n __arm64_sys_madvise+0x90/0xe8\n invoke_syscall.constprop.0+0xdc/0x1d8\n do_el0_svc+0xf4/0x3f8\n el0_svc+0x58/0x120\n el0t_64_sync_handler+0xb8/0xc0\n el0t_64_sync+0x19c/0x1a0\n[...]\n\nOn arm64, pmd_leaf() will return true even if the pmd is invalid due to\npmd_present_invalid() check. So in pmdp_invalidate() the file_map_count\nwill not only decrease once but also increase once. Then in set_pte_at(),\nthe file_map_count increase again, and so trigger BUG_ON() unexpectedly.\n\nAdd !pmd_present_invalid() check in pmd_user_accessible_page() to fix the\nproblem.",
"id": "GHSA-j4gx-6m2g-9p7c",
"modified": "2024-09-11T18:31:02Z",
"published": "2024-08-21T09:31:32Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-48897"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/21e5eca0ac9046da9918a919bc92b7b5a78d27e7"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/74c2f81054510d45b813548cb0a1c4ebf87cdd5f"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.