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CVE-2026-80984

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: net/smc: do not dereference an unset send buffer on the SMC-D teardown path smc_close_stream_wait() calls smc_tx_prepared_sends() from inside its sk_wait_event() condition, and sk_wait_event() evaluates that condition once with the socket lock released. smcd_buf_detach() clears conn->sndbuf_desc from smc_conn_kill() under lock_sock(), so a link group terminating while a socket waits there leaves the helper dereferencing NULL, faulting out of close(). SIOCOUTQ reads the field by hand, and smc_close_cancel_work() drops the lock across two cancel_*_sync() calls. Sample the pointer once in the helper, report nothing prepared while it is unset, and bound the ioctl the same way. The receive tasklet dereferences the field directly in smc_cdc_msg_recv_action(), not through this helper; 1/2 is what keeps it from running that late.

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-11 20:19:04.920000
Last modified
2026-10-19 09:17:30.953000
View original CVE JSON
{
  "id": "CVE-2026-80984",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-11T20:19:04.920",
  "lastModified": "2026-10-19T09:17:30.953",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: do not dereference an unset send buffer on the SMC-D teardown path\n\nsmc_close_stream_wait() calls smc_tx_prepared_sends() from inside its\nsk_wait_event() condition, and sk_wait_event() evaluates that condition\nonce with the socket lock released. smcd_buf_detach() clears\nconn->sndbuf_desc from smc_conn_kill() under lock_sock(), so a link group\nterminating while a socket waits there leaves the helper dereferencing\nNULL, faulting out of close(). SIOCOUTQ reads the field by hand, and\nsmc_close_cancel_work() drops the lock across two cancel_*_sync() calls.\n\nSample the pointer once in the helper, report nothing prepared while it is\nunset, and bound the ioctl the same way. The receive tasklet dereferences\nthe field directly in smc_cdc_msg_recv_action(), not through this helper;\n1/2 is what keeps it from running that late."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "net/smc/af_smc.c",
            "net/smc/smc_tx.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "21f6f41e82e59740e26e06e77bdf58dc7f6f08dd",
              "lessThan": "ab26e12dd5d2f43d939fcf456933a816e81d2e51",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "ae2be35cbed2c8385e890147ea321a3fcc3ca5fa",
              "lessThan": "e3fcff8d22a6c9540748846cd800443a643553a6",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "ae2be35cbed2c8385e890147ea321a3fcc3ca5fa",
              "lessThan": "f950e1b1f0aad334f9a9ee552c4dd5b794ebdd45",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "ae2be35cbed2c8385e890147ea321a3fcc3ca5fa",
              "lessThan": "f517cf02033801a28f98d86ca613a3533cf066b3",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "ae2be35cbed2c8385e890147ea321a3fcc3ca5fa",
              "lessThan": "b395dd319cea422239cb45b998fb38d7e373af87",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "6.6.66",
              "lessThan": "6.6.157",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "net/smc/af_smc.c",
            "net/smc/smc_tx.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.10",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.10",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.157",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.109",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.50",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.4",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/ab26e12dd5d2f43d939fcf456933a816e81d2e51",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b395dd319cea422239cb45b998fb38d7e373af87",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e3fcff8d22a6c9540748846cd800443a643553a6",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f517cf02033801a28f98d86ca613a3533cf066b3",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f950e1b1f0aad334f9a9ee552c4dd5b794ebdd45",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}