smc91x: fix broken irq-context in PREEMPT_RT

{
  "id": "1f2ec535152a2617e57fce5c87c842dc53e55dff0a59872d7dfb5d91ca9180de",
  "url": "https://osv.dev/vulnerability/CVE-2025-71132",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "smc91x: fix broken irq-context in PREEMPT_RT",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: smc91x: fix broken irq-context in PREEMPT_RT When smc91x.c is built with PREEMPT_RT, the following splat occurs in FVP_RevC: [ 13.055000] smc91x LNRO0003:00 eth0: link up, 10Mbps, half-duplex, lpa 0x0000 [ 13.062137] BUG: workqueue leaked atomic, lock or RCU: kworker/2:1[106] [ 13.062137] preempt=0x00000000 lock=0->0 RCU=0->1 workfn=mld_ifc_work [ 13.062266] C ** replaying previous printk message ** [ 13.062266] CPU: 2 UID: 0 PID: 106 Comm: kworker/2:1 Not tainted 6.18.0-dirty #179 PREEMPT_{RT,(full)} [ 13.062353] Hardware name: , BIOS [ 13.062382] Workqueue: mld mld_ifc_work [ 13.062469] Call trace: [ 13.062494] show_stack+0x24/0x40 (C) [ 13.062602] __dump_stack+0x28/0x48 [ 13.062710] dump_stack_lvl+0x7c/0xb0 [ 13.062818] dump_stack+0x18/0x34 [ 13.062926] process_scheduled_works+0x294/0x450 [ 13.063043] worker_thread+0x260/0x3d8 [ 13.063124] kthread+0x1c4/0x228 [ 13.063235] ret_from_fork+0x10/0x20 This happens because smc_special_trylock() disables IRQs even on PREEMPT_RT, but smc_special_unlock() does not restore IRQs on PREEMPT_RT. The reason is that smc_special_unlock() calls spin_unlock_irqrestore(), and rcu_read_unlock_bh() in __dev_queue_xmit() cannot invoke rcu_read_unlock() through __local_bh_enable_ip() when current->softirq_disable_cnt becomes zero. To address this issue, replace smc_special_trylock() with spin_trylock_irqsave().",
    "evidence": "osv:CVE-2025-71132",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.15.198",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.1.160",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.6.120",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.12.64",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.18.4",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "CVE-2025-71132",
      "aliases": [
        "CVE-2025-71132"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
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                  "introduced": "342a93247e0837101f27bbcca26f402902df98dc"
                },
                {
                  "fixed": "1c4cb705e733250d13243f6a69b8b5a92e39b9f6"
                },
                {
                  "fixed": "9d222141b00156509d67d80c771fbefa92c43ace"
                },
                {
                  "fixed": "ef277ae121b3249c99994652210a326b52d527b0"
                },
                {
                  "fixed": "36561b86cb2501647662cfaf91286dd6973804a6"
                },
                {
                  "fixed": "b6018d5c1a8f09d5efe4d6961d7ee45fdf3a7ce3"
                },
                {
                  "fixed": "6402078bd9d1ed46e79465e1faaa42e3458f8a33"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-71132.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.15.0"
                },
                {
                  "fixed": "5.15.198"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.16.0"
                },
                {
                  "fixed": "6.1.160"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.2.0"
                },
                {
                  "fixed": "6.6.120"
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            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.7.0"
                },
                {
                  "fixed": "6.12.64"
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              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.13.0"
                },
                {
                  "fixed": "6.18.4"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-71132.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:40.027826634Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/1c4cb705e733250d13243f6a69b8b5a92e39b9f6",
        "https://git.kernel.org/stable/c/36561b86cb2501647662cfaf91286dd6973804a6",
        "https://git.kernel.org/stable/c/6402078bd9d1ed46e79465e1faaa42e3458f8a33",
        "https://git.kernel.org/stable/c/9d222141b00156509d67d80c771fbefa92c43ace",
        "https://git.kernel.org/stable/c/b6018d5c1a8f09d5efe4d6961d7ee45fdf3a7ce3",
        "https://git.kernel.org/stable/c/ef277ae121b3249c99994652210a326b52d527b0",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/71xxx/CVE-2025-71132.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2025-71132",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/71xxx/CVE-2025-71132.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2025-71132",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 507713,
  "published_at": "2026-01-14T15:07:47.86+00:00"
}