{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "baa355fd331424526e742d41d9b90d5f9d10f716"
            },
            {
              "fixed": "bc2f5eabaaf60ec18da70b619a8fba1bfb7dea3a"
            },
            {
              "fixed": "f87c08060818ebb19bafed37c38244538da25097"
            },
            {
              "fixed": "6f5c272d71845a669e4c8ee5c72b376e29a0e6e5"
            },
            {
              "fixed": "be106f7855f03d3128ed0ce70ba74b484a90b473"
            },
            {
              "fixed": "e3dd774dbfd0b5bc2dbd0995221751b1234f8205"
            },
            {
              "fixed": "10065fb891651d9541e7a5a2db84c1e656ece4f9"
            },
            {
              "fixed": "d640efe94d86d3be893d4c19220362546a637e90"
            },
            {
              "fixed": "e923bd21058ea02fd0dcd3549d151d143fd036e5"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.8.0"
            },
            {
              "fixed": "5.10.265"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.216"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.183"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.151"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.103"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.44"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.1.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74482.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/huge_memory: unlock i_mmap_rwsem before releasing after-split folios\n\n__folio_split() keeps dereferencing the mapping after the split:\nshmem_uncharge(mapping-\u003ehost) and remap_page() while the folios are still\nfrozen/locked, and i_mmap_unlock_read(mapping) at the very end, after the\nafter-split folios have been unlocked and freed.\n\nNothing holds an inode reference across that.  The split relies on @folio\n-- which the beyond-EOF drop loop never removes, as it starts at\nfolio_next(folio) -- staying locked and in the page cache to hold off\neviction.  But the unlock loop unlocks @folio before i_mmap_unlock_read()\nruns.  If the caller's @lock_at is a tail beyond EOF, as memory_failure()\npasses when splitting a poisoned tail of a shmem THP that reaches past\ni_size during truncation, it too is gone from the page cache; so once\n@folio is unlocked no locked, in-cache folio pins the inode, and a\nconcurrent final iput() can evict and RCU-free it before\ni_mmap_unlock_read() touches i_mmap_rwsem:\n\n  BUG: KASAN: slab-use-after-free in __up_read+0x634/0x790\n   i_mmap_unlock_read include/linux/fs.h:537 [inline]\n   __folio_split+0x732/0x1640 mm/huge_memory.c:4100\n   try_to_split_thp_page+0xab/0x390 mm/memory-failure.c:1675\n   memory_failure+0x1394/0x26e0 mm/memory-failure.c:2470\n\n  Freed by task 4601:\n   shmem_free_in_core_inode+0x54/0xb0 mm/shmem.c:5177\n   evict+0x57f/0xac0 fs/inode.c:870\n\nDo every mapping dereference while @folio still pins the inode: drop\ni_mmap_rwsem right after remap_page(), before the loop that unlocks and\nfrees the after-split folios, and clear @mapping so the exit path does not\nunlock it again.  shmem_uncharge() and remap_page() already run before\nthat point, so after this nothing past the unlock loop touches the inode\nor the mapping.\n\nThis is now a rule the split depends on, alongside keeping @folio frozen\nuntil the page cache is updated: no inode or mapping dereference once the\nafter-split folios start being unlocked.",
  "id": "CVE-2026-74482",
  "modified": "2026-08-21T03:30:26.799726232Z",
  "published": "2026-08-15T12:27:15.083Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/10065fb891651d9541e7a5a2db84c1e656ece4f9"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6f5c272d71845a669e4c8ee5c72b376e29a0e6e5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/bc2f5eabaaf60ec18da70b619a8fba1bfb7dea3a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/be106f7855f03d3128ed0ce70ba74b484a90b473"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d640efe94d86d3be893d4c19220362546a637e90"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e3dd774dbfd0b5bc2dbd0995221751b1234f8205"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e923bd21058ea02fd0dcd3549d151d143fd036e5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f87c08060818ebb19bafed37c38244538da25097"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74482.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-74482"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "mm/huge_memory: unlock i_mmap_rwsem before releasing after-split folios"
}