{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "09e328e47a695b0d346598f5d6593ee598e64885"
            },
            {
              "fixed": "3dd07b369371a2f29e1c3caf1ade85bb92b4c551"
            },
            {
              "fixed": "b2da0d488a1c72956ebb0a57015ee8ee6a2f7748"
            },
            {
              "fixed": "a7f8d26e653ee43b0b572984b8ec544d3b3b6f3c"
            },
            {
              "fixed": "71dc206f2e2a645dac78879768762451aa1799f7"
            },
            {
              "fixed": "764586f8f6180084c5a7d622120f526acc6ce0c9"
            },
            {
              "fixed": "28ac2dd416482d1c763c4af5d61af465b387fb50"
            },
            {
              "fixed": "43a7d8ae9f645dc00235cfa4bf57673c20b769f8"
            },
            {
              "fixed": "ecbe7d36dc2de07e5dfbb4a8ff5b315ab43de820"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "5.10.0"
            },
            {
              "fixed": "5.10.270"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.221"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.188"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.157"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.109"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.50"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89508.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/ucma: Lock the handler in ucma_set_ib_path()\n\nucma_set_ib_path() calls ucma_event_handler() straight from the write()\npath, without the handler lock that keeps ctx-\u003efile stable while a uevent\nis queued.  The handler re-reads ctx-\u003efile for every dereference:\n\n\tmutex_lock(\u0026ctx-\u003efile-\u003emut);\t\t\t/* file A */\n\tlist_add_tail(\u0026uevent-\u003elist, \u0026ctx-\u003efile-\u003eevent_list);\t/* file B */\n\tmutex_unlock(\u0026ctx-\u003efile-\u003emut);\t\t\t/* file B */\n\twake_up_interruptible(\u0026ctx-\u003efile-\u003epoll_wait);\t/* file B */\n\nA concurrent ucma_migrate_id() reassigns ctx-\u003efile while the SET_OPTION\ncaller sleeps in mutex_lock(), so the list_add_tail() lands on file B's\nevent_list while only file A's mutex is held, racing every other user of\nthat list:\n\n  BUG: KASAN: slab-use-after-free in __list_add_valid_or_report+0x1aa/0x1c0\n  Read of size 8 at addr ffff888153c6a418 by task poc_corr/486\n  Call Trace:\n   __list_add_valid_or_report+0x1aa/0x1c0\n   ucma_event_handler+0x1be/0xc00\n   ucma_set_ib_path+0x45e/0x710\n   ucma_set_option+0x32e/0x590\n   ucma_write+0x1f9/0x330\n  Allocated by task 505:\n   ucma_write_cm_event+0x1a1/0x660\n  Freed by task 505:\n   kfree+0x1da/0x4c0\n   ucma_get_event+0x5d5/0x7e0\n\nThe freed object is a ucma_event that another thread dequeued from file B's\nlist under file B's mutex.  File A's mut is left held on top of that,\nwedging its next writer in uninterruptible sleep.\n\nThis path needs a bound and address-resolved cm_id, so it requires an RDMA\ndevice to be present.\n\nTake the handler lock around the call.",
  "id": "CVE-2026-89508",
  "modified": "2026-09-15T03:30:52.543696258Z",
  "published": "2026-09-11T19:43:54.682Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/28ac2dd416482d1c763c4af5d61af465b387fb50"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3dd07b369371a2f29e1c3caf1ade85bb92b4c551"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/43a7d8ae9f645dc00235cfa4bf57673c20b769f8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/71dc206f2e2a645dac78879768762451aa1799f7"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/764586f8f6180084c5a7d622120f526acc6ce0c9"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a7f8d26e653ee43b0b572984b8ec544d3b3b6f3c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b2da0d488a1c72956ebb0a57015ee8ee6a2f7748"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ecbe7d36dc2de07e5dfbb4a8ff5b315ab43de820"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89508.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-89508"
    },
    {
      "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": "RDMA/ucma: Lock the handler in ucma_set_ib_path()"
}