{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:12",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:13",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "7.0.10-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "In the Linux kernel, the following vulnerability has been resolved:  powerpc/64s: Fix unmap race with PMD migration entries  The following race is possible with migration swap entries or device-private THP entries. e.g. when move_pages is called on a PMD THP page, then there maybe an intermediate state, where PMD entry acts as a migration swap entry (pmd_present() is true). Then if an munmap happens at the same time, then this VM_BUG_ON() can happen in pmdp_huge_get_and_clear_full().  This patch fixes that.  Thread A: move_pages() syscall   add_folio_for_migration()     mmap_read_lock(mm)     folio_isolate_lru(folio)     mmap_read_unlock(mm)    do_move_pages_to_node()     migrate_pages()       try_to_migrate_one()         spin_lock(ptl)         set_pmd_migration_entry()           pmdp_invalidate()     # PMD: _PAGE_INVALID | _PAGE_PTE | pfn           set_pmd_at()          # PMD: migration swap entry (pmd_present=0)         spin_unlock(ptl)         [page copy phase]       # \u003c--- RACE WINDOW --\u003e  Thread B: munmap()   mmap_write_downgrade(mm)   unmap_vmas() -\u003e zap_pmd_range()     zap_huge_pmd()       __pmd_trans_huge_lock()         pmd_is_huge():          # !pmd_present \u0026\u0026 !pmd_none -\u003e TRUE (swap entry)         pmd_lock() -\u003e \t\t# spin_lock(ptl), waits for Thread A to release ptl       pmdp_huge_get_and_clear_full()         VM_BUG_ON(!pmd_present(*pmdp))  # HITS!  [  287.738700][ T1867] ------------[ cut here ]------------ [  287.743843][ T1867] kernel BUG at arch/powerpc/mm/book3s64/pgtable.c:187! cpu 0x0: Vector: 700 (Program Check) at [c00000044037f4f0]     pc: c000000000094ca4: pmdp_huge_get_and_clear_full+0x6c/0x23c     lr: c000000000645dec: zap_huge_pmd+0xb0/0x868     sp: c00000044037f790    msr: 800000000282b033   current = 0xc0000004032c1a00   paca    = 0xc000000004fe0000   irqmask: 0x03   irq_happened: 0x09     pid   = 1867, comm = a.out kernel BUG at :187! Linux version 6.19.0-12136-g14360d4f917c-dirty (powerpc64le-linux-gnu-gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40) #27 SMP PREEMPT Sun Feb 22 10:38:56 IST 2026 enter ? for help [link register   ] c000000000645dec zap_huge_pmd+0xb0/0x868 [c00000044037f790] c00000044037f7d0 (unreliable) [c00000044037f7d0] c000000000645dcc zap_huge_pmd+0x90/0x868 [c00000044037f840] c0000000005724cc unmap_page_range+0x176c/0x1f40 [c00000044037fa00] c000000000572ea0 unmap_vmas+0xb0/0x1d8 [c00000044037fa90] c0000000005af254 unmap_region+0xb4/0x128 [c00000044037fb50] c0000000005af400 vms_complete_munmap_vmas+0x138/0x310 [c00000044037fbe0] c0000000005b0f1c do_vmi_align_munmap+0x1ec/0x238 [c00000044037fd30] c0000000005b3688 __vm_munmap+0x170/0x1f8 [c00000044037fdf0] c000000000587f74 sys_munmap+0x2c/0x40 [c00000044037fe10] c000000000032668 system_call_exception+0x128/0x350 [c00000044037fe50] c00000000000d05c system_call_vectored_common+0x15c/0x2ec ---- Exception: 3000 (System Call Vectored) at 0000000010064a2c SP (7fff9b1ee9c0) is in userspace 0:mon\u003e zh  commit a30b48bf1b24 (\"mm/migrate_device: implement THP migration of zone device pages\"), enabled migration for device-private PMD entries. Hence this is one other path where this warning could get trigger from.   ------------[ cut here ]------------  WARNING: arch/powerpc/mm/book3s64/hash_pgtable.c:199 at hash__pmd_hugepage_update+0x48/0x284, CPU#3: hmm-tests/1905  Modules linked in: test_hmm  CPU: 3 UID: 0 PID: 1905 Comm: hmm-tests Tainted: G    B   W    L   N  7.0.0-rc1-01438-g7e2f0ee7581c #21 PREEMPT  Tainted: [B]=BAD_PAGE, [W]=WARN, [L]=SOFTLOCKUP, [N]=TEST  Hardware name: IBM pSeries (emulated by qemu) POWER10 (architected) 0x801200 0xf000006 of:SLOF,git-ee03ae pSeries  NIP [c000000000096b70] hash__pmd_hugepage_update+0x48/0x284  LR [c000000000096e7c] hash__pmdp_huge_get_and_clear+0xd0/0xd4  Call Trace:  [c000000604707670] [c000000004e102b8] 0xc000000004e102b8 (unreliable)  [c000000604707700] [c00000000064ec3c] set_pmd_migration_entry+0x414/0x498  [c000000604707760] [c00000000063e5a4] migrate_vma_col ---truncated---",
  "id": "DEBIAN-CVE-2026-53108",
  "modified": "2026-09-14T16:47:30.517281802Z",
  "published": "2026-06-24T17:17:25.107Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-53108"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "upstream": [
    "CVE-2026-53108"
  ]
}