CVE-2026-90065

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: net/smc: release the internal TCP sock on IPPROTO_SMC socket creation failure IPPROTO_SMC sockets create an internal TCP sock ("clcsock") from the proto->init hook. When socket creation fails after proto->init has run - e.g. a cgroup BPF program attached to BPF_CGROUP_INET_SOCK_CREATE denies the socket - sk_common_release() only invokes sk_prot->destroy if it is set, but neither smc_inet_prot nor smc_inet6_prot defines it, and smc_destruct() returns early unless sk_state is SMC_CLOSED. As a result, every failing socket(AF_INET, SOCK_STREAM, IPPROTO_SMC) call leaks one tcp_sock, so an unprivileged task able to attach a deny-all BPF_CGROUP_INET_SOCK_CREATE program to its own cgroup can grow kernel memory unboundedly. Add a .destroy hook to both protos that releases the clcsock via smc_clcsock_release(). smc_sk_init() hashes the sock into the smc hashinfo before the clcsock is created, and smc_diag dumps walk that hash dereferencing smc->clcsock without taking clcsock_release_lock, while sk_common_release() calls .destroy before .unhash. Unhash the sock before releasing the clcsock, as __smc_release() does, so a concurrent dump cannot observe the release; the second unhash in sk_common_release() is a no-op.

Severity

Not scored

CVSS score

Not available

Vulnerability status

Received

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2026-09-17 17:16:55.327000

Last modified

2026-10-19 09:18:54.977000

View original CVE JSON

{
  "id": "CVE-2026-90065",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-17T17:16:55.327",
  "lastModified": "2026-10-19T09:18:54.977",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: release the internal TCP sock on IPPROTO_SMC socket creation failure\n\nIPPROTO_SMC sockets create an internal TCP sock (\"clcsock\") from the\nproto->init hook. When socket creation fails after proto->init has\nrun - e.g. a cgroup BPF program attached to BPF_CGROUP_INET_SOCK_CREATE\ndenies the socket - sk_common_release() only invokes sk_prot->destroy\nif it is set, but neither smc_inet_prot nor smc_inet6_prot defines it,\nand smc_destruct() returns early unless sk_state is SMC_CLOSED. As a\nresult, every failing socket(AF_INET, SOCK_STREAM, IPPROTO_SMC) call\nleaks one tcp_sock, so an unprivileged task able to attach a deny-all\nBPF_CGROUP_INET_SOCK_CREATE program to its own cgroup can grow kernel\nmemory unboundedly.\n\nAdd a .destroy hook to both protos that releases the clcsock via\nsmc_clcsock_release(). smc_sk_init() hashes the sock into the smc\nhashinfo before the clcsock is created, and smc_diag dumps walk that\nhash dereferencing smc->clcsock without taking clcsock_release_lock,\nwhile sk_common_release() calls .destroy before .unhash. Unhash the\nsock before releasing the clcsock, as __smc_release() does, so a\nconcurrent dump cannot observe the release; the second unhash in\nsk_common_release() is a no-op."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "net/smc/smc_inet.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "d25a92ccae6bed02327b63d138e12e7806830f78",
              "lessThan": "2f4ece7fed6d915ec64b7735962c0d84d6261032",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d25a92ccae6bed02327b63d138e12e7806830f78",
              "lessThan": "84180988a455fd8e147c6b35c8df65d8b8cc76c2",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d25a92ccae6bed02327b63d138e12e7806830f78",
              "lessThan": "94a913cd521c0f0408820bcdbd80dadf076d97b5",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d25a92ccae6bed02327b63d138e12e7806830f78",
              "lessThan": "cec261b0b4c5c0b044165303198d10ffcdf3414c",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "net/smc/smc_inet.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.11",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.11",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.110",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.52",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.6",
              "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/2f4ece7fed6d915ec64b7735962c0d84d6261032",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/84180988a455fd8e147c6b35c8df65d8b8cc76c2",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/94a913cd521c0f0408820bcdbd80dadf076d97b5",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/cec261b0b4c5c0b044165303198d10ffcdf3414c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}