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FKIE_CVE-2026-80983

Vulnerability from fkie_nvd - Published: 2026-09-11 20:19 - Updated: 2026-09-14 13:18
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved: net/smc: fix socket refcount leak in smc_switch_conns() smc_switch_conns() takes a reference on the SMC socket before dropping lgr->conns_lock, so the connection stays alive while the CDC slot is fetched: sock_hold(&smc->sk); read_unlock_bh(&lgr->conns_lock); /* pre-fetch buffer outside of send_lock, might sleep */ rc = smc_cdc_get_free_slot(conn, to_lnk, &wr_buf, NULL, &pend); if (rc) goto err_out; The err_out label only drops the wr_tx link reference, so this early exit returns without the matching sock_put(). The second error exit is not affected, because sock_put() has already run by then. A leaked sk_refcnt means the smc_sock is never destroyed. Its send and receive buffers stay allocated, and for a user socket the reference held on the network namespace is never released, so the netns can no longer be torn down. smc_cdc_get_free_slot() fails when the target link goes down or when the connection has been killed while the switch is in progress. Both are reachable during the link failover this function implements, so the leak is triggered by the same hardware events that make smc_switch_conns() run in the first place. Restructure so there is a single sock_put() covering both outcomes, instead of adding a second one to the error path.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/09d7a9e162ee1a269878c126aee3d7eff43e4130
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/719296c4aa8213d4ac8002e77d5956d436bc98d0
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/84dea0585f6b538ae895a8b1d025f4897737f3b1
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/a3378466704e0bbe93aef9769552dca7673a7eb6
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/d89dc1bd8845c669a700eee58c64ebd3cc1b6d2d
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/d9a879ac25958bdaecb669ce70e58f8e2ff170de
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/e20227019d9da73f8fdf16f0951c2e188c84933f
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/smc/smc_core.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "a3378466704e0bbe93aef9769552dca7673a7eb6",
              "status": "affected",
              "version": "95f7f3e7dc6bd2e735cb5de11734ea2222b1e05a",
              "versionType": "git"
            },
            {
              "lessThan": "e20227019d9da73f8fdf16f0951c2e188c84933f",
              "status": "affected",
              "version": "95f7f3e7dc6bd2e735cb5de11734ea2222b1e05a",
              "versionType": "git"
            },
            {
              "lessThan": "09d7a9e162ee1a269878c126aee3d7eff43e4130",
              "status": "affected",
              "version": "95f7f3e7dc6bd2e735cb5de11734ea2222b1e05a",
              "versionType": "git"
            },
            {
              "lessThan": "84dea0585f6b538ae895a8b1d025f4897737f3b1",
              "status": "affected",
              "version": "95f7f3e7dc6bd2e735cb5de11734ea2222b1e05a",
              "versionType": "git"
            },
            {
              "lessThan": "d89dc1bd8845c669a700eee58c64ebd3cc1b6d2d",
              "status": "affected",
              "version": "95f7f3e7dc6bd2e735cb5de11734ea2222b1e05a",
              "versionType": "git"
            },
            {
              "lessThan": "d9a879ac25958bdaecb669ce70e58f8e2ff170de",
              "status": "affected",
              "version": "95f7f3e7dc6bd2e735cb5de11734ea2222b1e05a",
              "versionType": "git"
            },
            {
              "lessThan": "719296c4aa8213d4ac8002e77d5956d436bc98d0",
              "status": "affected",
              "version": "95f7f3e7dc6bd2e735cb5de11734ea2222b1e05a",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "99f19566b1c4d3dc4d934ee2ef43faadebb56d70",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "0d9ddf515cde793841f738490037560fd6559c63",
              "versionType": "git"
            },
            {
              "lessThan": "5.11",
              "status": "affected",
              "version": "5.10.90",
              "versionType": "semver"
            },
            {
              "lessThan": "5.15",
              "status": "affected",
              "version": "5.14.14",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/smc/smc_core.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.15"
            },
            {
              "lessThan": "5.15",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.221",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.188",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.157",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.109",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.50",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3-rc1",
              "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/smc: fix socket refcount leak in smc_switch_conns()\n\nsmc_switch_conns() takes a reference on the SMC socket before dropping\nlgr-\u003econns_lock, so the connection stays alive while the CDC slot is\nfetched:\n\n        sock_hold(\u0026smc-\u003esk);\n        read_unlock_bh(\u0026lgr-\u003econns_lock);\n        /* pre-fetch buffer outside of send_lock, might sleep */\n        rc = smc_cdc_get_free_slot(conn, to_lnk, \u0026wr_buf, NULL, \u0026pend);\n        if (rc)\n                goto err_out;\n\nThe err_out label only drops the wr_tx link reference, so this early exit\nreturns without the matching sock_put(). The second error exit is not\naffected, because sock_put() has already run by then.\n\nA leaked sk_refcnt means the smc_sock is never destroyed. Its send and\nreceive buffers stay allocated, and for a user socket the reference held\non the network namespace is never released, so the netns can no longer be\ntorn down.\n\nsmc_cdc_get_free_slot() fails when the target link goes down or when the\nconnection has been killed while the switch is in progress. Both are\nreachable during the link failover this function implements, so the leak\nis triggered by the same hardware events that make smc_switch_conns() run\nin the first place.\n\nRestructure so there is a single sock_put() covering both outcomes,\ninstead of adding a second one to the error path."
    }
  ],
  "id": "CVE-2026-80983",
  "lastModified": "2026-09-14T13:18:53.090",
  "metrics": {},
  "published": "2026-09-11T20:19:04.787",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/09d7a9e162ee1a269878c126aee3d7eff43e4130"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/719296c4aa8213d4ac8002e77d5956d436bc98d0"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/84dea0585f6b538ae895a8b1d025f4897737f3b1"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/a3378466704e0bbe93aef9769552dca7673a7eb6"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/d89dc1bd8845c669a700eee58c64ebd3cc1b6d2d"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/d9a879ac25958bdaecb669ce70e58f8e2ff170de"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/e20227019d9da73f8fdf16f0951c2e188c84933f"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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