CVE-2026-72491 (GCVE-0-2026-72491)

Vulnerability from cvelistv5 – Published: 2026-08-15 05:57 – Updated: 2026-08-17 05:44
VLAI
Title
net/9p: fix race condition on rdma->state in trans_rdma.c
Summary
In the Linux kernel, the following vulnerability has been resolved: net/9p: fix race condition on rdma->state in trans_rdma.c The rdma->state field is modified without holding req_lock in both recv_done() and p9_cm_event_handler(), while rdma_request() accesses the same field under the req_lock spinlock. This inconsistent locking creates a race condition: - recv_done() running in softirq completion context sets rdma->state = P9_RDMA_FLUSHING without acquiring req_lock - p9_cm_event_handler() modifies rdma->state at multiple points (ADDR_RESOLVED, ROUTE_RESOLVED, ESTABLISHED, CLOSED) without req_lock - rdma_request() uses spin_lock_irqsave(&rdma->req_lock, flags) to protect the read-modify-write of rdma->state The race can cause lost state transitions: recv_done() or the CM event handler could set state to FLUSHING/CLOSED while rdma_request() is concurrently checking or modifying state under the lock, leading to the FLUSHING transition being silently overwritten by CLOSING. This corrupts the connection state machine and can cause use-after-free on RDMA request objects during teardown. Fix by adding req_lock protection to all rdma->state modifications in recv_done() and p9_cm_event_handler(), matching the pattern already used in rdma_request(). Use spin_lock_irqsave/spin_unlock_irqrestore in the CM event handler since it can race with recv_done() which runs in softirq context. Tested with a kernel module that races two threads (simulating rdma_request and recv_done/CM handler) on rdma->state with proper locking: 5.5M+ FLUSHING writes over 27M iterations with 0 lost transitions.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 473c7dd1d7b59ff8f88a5154737e3eac78a96e5b , < 4cee2b8766045059d5e0b8114837b4a8efe827ac (git)
Affected: 473c7dd1d7b59ff8f88a5154737e3eac78a96e5b , < 5424138848eb7d7d8a7196676e90a2cbf2142454 (git)
Affected: 473c7dd1d7b59ff8f88a5154737e3eac78a96e5b , < 3970a19a80de530b801b6256354d4a529a9a2d6c (git)
Affected: 473c7dd1d7b59ff8f88a5154737e3eac78a96e5b , < 8aadc136d8e8d8fc95d7982d213cfe2234dfcf2b (git)
Affected: 473c7dd1d7b59ff8f88a5154737e3eac78a96e5b , < 151f8cf5b23d8a534d884432a82a6d54d5a61989 (git)
Affected: 473c7dd1d7b59ff8f88a5154737e3eac78a96e5b , < 13bf9879b778b2f4b260b45bed18f31806120d1e (git)
Affected: 473c7dd1d7b59ff8f88a5154737e3eac78a96e5b , < ebbcbe5c0db215feecc17def06178da443f4eea6 (git)
Affected: 473c7dd1d7b59ff8f88a5154737e3eac78a96e5b , < 7d54894a1ee265a72d70f7cae1da6cc774cccc71 (git)
Affected: 3479b3c35e82ed10aa0ca2ee9e78c4eded06ba62 (git)
Affected: c01ddaa54d7411e964ffd250c018d8469c5852f2 (git)
Affected: 9e69c673fe077b8dc491cd8406c9bdcb1f76dee2 (git)
Affected: e48e7e27e4dfd00c81e0381e7cee610cce021452 (git)
Affected: 4.4.185 , < 4.5 (semver)
Affected: 4.9.185 , < 4.10 (semver)
Affected: 4.14.132 , < 4.15 (semver)
Affected: 4.19.57 , < 4.20 (semver)
guessed Create a notification for this product.
Linux Linux Affected: 4.20
Unaffected: 0 , < 4.20 (semver)
Unaffected: 5.10.261 , ≤ 5.10.* (semver)
Unaffected: 5.15.212 , ≤ 5.15.* (semver)
Unaffected: 6.1.178 , ≤ 6.1.* (semver)
Unaffected: 6.6.145 , ≤ 6.6.* (semver)
Unaffected: 6.12.97 , ≤ 6.12.* (semver)
Unaffected: 6.18.40 , ≤ 6.18.* (semver)
Unaffected: 7.1.5 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/9p/trans_rdma.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "4cee2b8766045059d5e0b8114837b4a8efe827ac",
              "status": "affected",
              "version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
              "versionType": "git"
            },
            {
              "lessThan": "5424138848eb7d7d8a7196676e90a2cbf2142454",
              "status": "affected",
              "version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
              "versionType": "git"
            },
            {
              "lessThan": "3970a19a80de530b801b6256354d4a529a9a2d6c",
              "status": "affected",
              "version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
              "versionType": "git"
            },
            {
              "lessThan": "8aadc136d8e8d8fc95d7982d213cfe2234dfcf2b",
              "status": "affected",
              "version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
              "versionType": "git"
            },
            {
              "lessThan": "151f8cf5b23d8a534d884432a82a6d54d5a61989",
              "status": "affected",
              "version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
              "versionType": "git"
            },
            {
              "lessThan": "13bf9879b778b2f4b260b45bed18f31806120d1e",
              "status": "affected",
              "version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
              "versionType": "git"
            },
            {
              "lessThan": "ebbcbe5c0db215feecc17def06178da443f4eea6",
              "status": "affected",
              "version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
              "versionType": "git"
            },
            {
              "lessThan": "7d54894a1ee265a72d70f7cae1da6cc774cccc71",
              "status": "affected",
              "version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "3479b3c35e82ed10aa0ca2ee9e78c4eded06ba62",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "c01ddaa54d7411e964ffd250c018d8469c5852f2",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "9e69c673fe077b8dc491cd8406c9bdcb1f76dee2",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "e48e7e27e4dfd00c81e0381e7cee610cce021452",
              "versionType": "git"
            },
            {
              "lessThan": "4.5",
              "status": "affected",
              "version": "4.4.185",
              "versionType": "semver"
            },
            {
              "lessThan": "4.10",
              "status": "affected",
              "version": "4.9.185",
              "versionType": "semver"
            },
            {
              "lessThan": "4.15",
              "status": "affected",
              "version": "4.14.132",
              "versionType": "semver"
            },
            {
              "lessThan": "4.20",
              "status": "affected",
              "version": "4.19.57",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/9p/trans_rdma.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.20"
            },
            {
              "lessThan": "4.20",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.261",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.212",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.178",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.145",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.97",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.261",
                  "versionStartIncluding": "4.20",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.212",
                  "versionStartIncluding": "4.20",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.178",
                  "versionStartIncluding": "4.20",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.145",
                  "versionStartIncluding": "4.20",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.97",
                  "versionStartIncluding": "4.20",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.40",
                  "versionStartIncluding": "4.20",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.5",
                  "versionStartIncluding": "4.20",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "4.20",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "4.4.185",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "4.9.185",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "4.14.132",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "4.19.57",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/9p: fix race condition on rdma-\u003estate in trans_rdma.c\n\nThe rdma-\u003estate field is modified without holding req_lock in both\nrecv_done() and p9_cm_event_handler(), while rdma_request() accesses\nthe same field under the req_lock spinlock. This inconsistent locking\ncreates a race condition:\n\n- recv_done() running in softirq completion context sets\n  rdma-\u003estate = P9_RDMA_FLUSHING without acquiring req_lock\n\n- p9_cm_event_handler() modifies rdma-\u003estate at multiple points\n  (ADDR_RESOLVED, ROUTE_RESOLVED, ESTABLISHED, CLOSED) without\n  req_lock\n\n- rdma_request() uses spin_lock_irqsave(\u0026rdma-\u003ereq_lock, flags) to\n  protect the read-modify-write of rdma-\u003estate\n\nThe race can cause lost state transitions: recv_done() or the CM\nevent handler could set state to FLUSHING/CLOSED while rdma_request()\nis concurrently checking or modifying state under the lock, leading to\nthe FLUSHING transition being silently overwritten by CLOSING. This\ncorrupts the connection state machine and can cause use-after-free on\nRDMA request objects during teardown.\n\nFix by adding req_lock protection to all rdma-\u003estate modifications in\nrecv_done() and p9_cm_event_handler(), matching the pattern already\nused in rdma_request(). Use spin_lock_irqsave/spin_unlock_irqrestore\nin the CM event handler since it can race with recv_done() which runs\nin softirq context.\n\nTested with a kernel module that races two threads (simulating\nrdma_request and recv_done/CM handler) on rdma-\u003estate with proper\nlocking: 5.5M+ FLUSHING writes over 27M iterations with 0 lost\ntransitions."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - The 9p RDMA client processes RDMA receive completions and CM disconnect events from the remote peer in recv_done() and p9_cm_event_handler(); a malicious or compromised 9p server over RoCE/iWARP can trigger err_out and concurrent teardown without local access.\nAC:L - The attacker controls both sides of the race by sending malformed 9p RDMA replies to drive recv_done() into err_out while forcing disconnects and concurrent rdma_request() error paths; no uncontrollable memory layout or rare victim state is required.\nPR:N - A remote malicious 9p RDMA server needs no credentials on the victim kernel; HPC clusters and virtio-9p backends with persistent trans=rdma mounts let the server alone time malformed replies against in-flight client requests.\nUI:N - No per-attack victim action is needed on existing 9p RDMA mounts\u2014automated workloads, parallel I/O, and server-initiated RDMA disconnects concurrently reach recv_done() and rdma_request() during normal filesystem operation.\nS:U - Impact is kernel heap corruption and local privilege escalation within the victim kernel security domain; UAF on p9_req_t during RDMA teardown does not cross VM, container, or IOMMU isolation boundaries.\nC:H - Lost FLUSHING state transitions corrupt the connection teardown state machine and cause use-after-free on RDMA request (p9_req_t) objects; UAF provides attacker-influenced freed-heap contents usable for arbitrary kernel memory disclosure.\nI:H - Corrupted rdma-\u003estate frees in-flight p9_req_t structures while send_done() and p9_client_cb() still hold references, enabling heap grooming and arbitrary kernel write or control-flow hijack primitives.\nA:H - Use-after-free during RDMA request teardown causes kernel oops or panic when dangling p9_req_t objects are accessed, and state-machine corruption alone can hang or crash the 9p RDMA transport."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:44:52.224Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/4cee2b8766045059d5e0b8114837b4a8efe827ac"
        },
        {
          "url": "https://git.kernel.org/stable/c/5424138848eb7d7d8a7196676e90a2cbf2142454"
        },
        {
          "url": "https://git.kernel.org/stable/c/3970a19a80de530b801b6256354d4a529a9a2d6c"
        },
        {
          "url": "https://git.kernel.org/stable/c/8aadc136d8e8d8fc95d7982d213cfe2234dfcf2b"
        },
        {
          "url": "https://git.kernel.org/stable/c/151f8cf5b23d8a534d884432a82a6d54d5a61989"
        },
        {
          "url": "https://git.kernel.org/stable/c/13bf9879b778b2f4b260b45bed18f31806120d1e"
        },
        {
          "url": "https://git.kernel.org/stable/c/ebbcbe5c0db215feecc17def06178da443f4eea6"
        },
        {
          "url": "https://git.kernel.org/stable/c/7d54894a1ee265a72d70f7cae1da6cc774cccc71"
        }
      ],
      "title": "net/9p: fix race condition on rdma-\u003estate in trans_rdma.c",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-72491",
    "datePublished": "2026-08-15T05:57:26.281Z",
    "dateReserved": "2026-08-09T03:40:39.936Z",
    "dateUpdated": "2026-08-17T05:44:52.224Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-72491",
      "date": "2026-09-20",
      "epss": "0.00724",
      "percentile": "0.52584"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "net/9p/trans_rdma.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "4cee2b8766045059d5e0b8114837b4a8efe827ac",
                    "status": "affected",
                    "version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "5424138848eb7d7d8a7196676e90a2cbf2142454",
                    "status": "affected",
                    "version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "3970a19a80de530b801b6256354d4a529a9a2d6c",
                    "status": "affected",
                    "version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "8aadc136d8e8d8fc95d7982d213cfe2234dfcf2b",
                    "status": "affected",
                    "version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "151f8cf5b23d8a534d884432a82a6d54d5a61989",
                    "status": "affected",
                    "version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "13bf9879b778b2f4b260b45bed18f31806120d1e",
                    "status": "affected",
                    "version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "ebbcbe5c0db215feecc17def06178da443f4eea6",
                    "status": "affected",
                    "version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "7d54894a1ee265a72d70f7cae1da6cc774cccc71",
                    "status": "affected",
                    "version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
                    "versionType": "git"
                  },
                  {
                    "status": "affected",
                    "version": "3479b3c35e82ed10aa0ca2ee9e78c4eded06ba62",
                    "versionType": "git"
                  },
                  {
                    "status": "affected",
                    "version": "c01ddaa54d7411e964ffd250c018d8469c5852f2",
                    "versionType": "git"
                  },
                  {
                    "status": "affected",
                    "version": "9e69c673fe077b8dc491cd8406c9bdcb1f76dee2",
                    "versionType": "git"
                  },
                  {
                    "status": "affected",
                    "version": "e48e7e27e4dfd00c81e0381e7cee610cce021452",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "4.5",
                    "status": "affected",
                    "version": "4.4.185",
                    "versionType": "semver"
                  },
                  {
                    "lessThan": "4.10",
                    "status": "affected",
                    "version": "4.9.185",
                    "versionType": "semver"
                  },
                  {
                    "lessThan": "4.15",
                    "status": "affected",
                    "version": "4.14.132",
                    "versionType": "semver"
                  },
                  {
                    "lessThan": "4.20",
                    "status": "affected",
                    "version": "4.19.57",
                    "versionType": "semver"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "net/9p/trans_rdma.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "4.20"
                  },
                  {
                    "lessThan": "4.20",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.10.*",
                    "status": "unaffected",
                    "version": "5.10.261",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.15.*",
                    "status": "unaffected",
                    "version": "5.15.212",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.1.*",
                    "status": "unaffected",
                    "version": "6.1.178",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.6.*",
                    "status": "unaffected",
                    "version": "6.6.145",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.12.*",
                    "status": "unaffected",
                    "version": "6.12.97",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.18.*",
                    "status": "unaffected",
                    "version": "6.18.40",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "7.1.*",
                    "status": "unaffected",
                    "version": "7.1.5",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "7.2",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/9p: fix race condition on rdma-\u003estate in trans_rdma.c\n\nThe rdma-\u003estate field is modified without holding req_lock in both\nrecv_done() and p9_cm_event_handler(), while rdma_request() accesses\nthe same field under the req_lock spinlock. This inconsistent locking\ncreates a race condition:\n\n- recv_done() running in softirq completion context sets\n  rdma-\u003estate = P9_RDMA_FLUSHING without acquiring req_lock\n\n- p9_cm_event_handler() modifies rdma-\u003estate at multiple points\n  (ADDR_RESOLVED, ROUTE_RESOLVED, ESTABLISHED, CLOSED) without\n  req_lock\n\n- rdma_request() uses spin_lock_irqsave(\u0026rdma-\u003ereq_lock, flags) to\n  protect the read-modify-write of rdma-\u003estate\n\nThe race can cause lost state transitions: recv_done() or the CM\nevent handler could set state to FLUSHING/CLOSED while rdma_request()\nis concurrently checking or modifying state under the lock, leading to\nthe FLUSHING transition being silently overwritten by CLOSING. This\ncorrupts the connection state machine and can cause use-after-free on\nRDMA request objects during teardown.\n\nFix by adding req_lock protection to all rdma-\u003estate modifications in\nrecv_done() and p9_cm_event_handler(), matching the pattern already\nused in rdma_request(). Use spin_lock_irqsave/spin_unlock_irqrestore\nin the CM event handler since it can race with recv_done() which runs\nin softirq context.\n\nTested with a kernel module that races two threads (simulating\nrdma_request and recv_done/CM handler) on rdma-\u003estate with proper\nlocking: 5.5M+ FLUSHING writes over 27M iterations with 0 lost\ntransitions."
          }
        ],
        "id": "CVE-2026-72491",
        "lastModified": "2026-08-17T06:19:17.397",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 9.8,
                "baseSeverity": "CRITICAL",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "HIGH",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 3.9,
              "impactScore": 5.9,
              "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
              "type": "Secondary"
            }
          ]
        },
        "published": "2026-08-15T06:22:23.400",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/13bf9879b778b2f4b260b45bed18f31806120d1e"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/151f8cf5b23d8a534d884432a82a6d54d5a61989"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/3970a19a80de530b801b6256354d4a529a9a2d6c"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/4cee2b8766045059d5e0b8114837b4a8efe827ac"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/5424138848eb7d7d8a7196676e90a2cbf2142454"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/7d54894a1ee265a72d70f7cae1da6cc774cccc71"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/8aadc136d8e8d8fc95d7982d213cfe2234dfcf2b"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/ebbcbe5c0db215feecc17def06178da443f4eea6"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Received"
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-09-01T10:36:54+00:00",
      "cve": "CVE-2026-72491",
      "id": "CVE-2026-72491",
      "initial_release_date": "2026-08-15T00:00:00+00:00",
      "product_status:known_affected": "14",
      "product_status:known_not_affected": "260",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: net/9p: fix race condition on rdma-\u003estate in trans_rdma.c",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-72491.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-09-15T01:25:07Z",
      "cve": "CVE-2026-72491",
      "id": "CVE-2026-72491",
      "initial_release_date": "2026-08-27T00:23:15Z",
      "product_status:known_affected": "356",
      "product_status:known_not_affected": "6",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-72491",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-72491.json",
      "version": "4"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.