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CVE-2026-98072

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: net/rds: use wq_has_sleeper() in release_in_xmit() release_in_xmit() clears RDS_IN_XMIT with clear_bit_unlock() and then checks waitqueue_active() to decide whether anyone needs waking. clear_bit_unlock() is only a release operation: it orders the critical section before the bit clear, but does not order the subsequent plain load of the wait queue head after it. The waiter side does the mirror image - it adds itself to the wait queue and then tests the bit. That is the classic store-buffering pattern: the releasing CPU can read the wait queue as empty while the waiting CPU still reads the bit as set, so the sleeper is never woken. The waiters are rds_conn_shutdown() and rds_tcp_reset_callbacks(), both in uninterruptible wait_event() with no timeout. A lost wake-up strands the shutdown worker on its single-threaded workqueue until some other sender releases the bit again - and on a connection that is being torn down precisely because it failed, there may never be another sender. The barrier used to be there: release_in_xmit() did clear_bit() followed by smp_mb__after_atomic() until commit 1422f28826d2 ("rds: introduce acquire/release ordering in acquire/release_in_xmit()") folded both into clear_bit_unlock(), which strengthened the lock hand-off but silently dropped the full barrier the wake-up check depends on. The refill counterpart, release_refill() in net/rds/ib_recv.c, still carries its smp_mb__after_atomic() for exactly this reason. Use wq_has_sleeper(), which is waitqueue_active() preceded by the required full barrier.

Severity
Not scored
CVSS score
Not available
Vulnerability status
Undergoing Analysis
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-25 11:17:36.450000
Last modified
2026-10-19 10:18:02.543000
View original CVE JSON
{
  "id": "CVE-2026-98072",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-25T11:17:36.450",
  "lastModified": "2026-10-19T10:18:02.543",
  "vulnStatus": "Undergoing Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/rds: use wq_has_sleeper() in release_in_xmit()\n\nrelease_in_xmit() clears RDS_IN_XMIT with clear_bit_unlock() and then\nchecks waitqueue_active() to decide whether anyone needs waking.\nclear_bit_unlock() is only a release operation: it orders the\ncritical section before the bit clear, but does not order the\nsubsequent plain load of the wait queue head after it.  The waiter\nside does the mirror image - it adds itself to the wait queue and\nthen tests the bit.  That is the classic store-buffering pattern: the\nreleasing CPU can read the wait queue as empty while the waiting CPU\nstill reads the bit as set, so the sleeper is never woken.\n\nThe waiters are rds_conn_shutdown() and rds_tcp_reset_callbacks(),\nboth in uninterruptible wait_event() with no timeout.  A lost wake-up\nstrands the shutdown worker on its single-threaded workqueue until\nsome other sender releases the bit again - and on a connection that\nis being torn down precisely because it failed, there may never be\nanother sender.\n\nThe barrier used to be there: release_in_xmit() did clear_bit()\nfollowed by smp_mb__after_atomic() until commit 1422f28826d2 (\"rds:\nintroduce acquire/release ordering in acquire/release_in_xmit()\")\nfolded both into clear_bit_unlock(), which strengthened the lock\nhand-off but silently dropped the full barrier the wake-up check\ndepends on.  The refill counterpart, release_refill() in\nnet/rds/ib_recv.c, still carries its smp_mb__after_atomic() for\nexactly this reason.\n\nUse wq_has_sleeper(), which is waitqueue_active() preceded by the\nrequired full barrier."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "net/rds/send.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "1e1e4316fcaeb9cd6bc56c91127e88625237dd44",
              "lessThan": "6f552364d97cf4005c7a58f11c9f79e14e269865",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "8c378cc522aedd5fa5aa53486b43a4d552fbbd5c",
              "lessThan": "a94b1dfc82454c5bc068e71c25393af674daf63b",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "52287ed416a10bc3d3e204a3186d9509ab3ee634",
              "lessThan": "5a806ed1eb46850ca4159a18b2a8c4b70f0c1341",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "4a4dffdff9ea6201665f5d0a5042011d09bd527f",
              "lessThan": "3d401934b7edb3ccb07d982dabadd04c45ee307c",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1422f28826d2a0c11e5240b3e951c9e214d8656e",
              "lessThan": "ed7ee0cd0e136d02f87f13181b1a89880463c7e9",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1422f28826d2a0c11e5240b3e951c9e214d8656e",
              "lessThan": "a269795107f45adc95975a83324f8fef40bec4ce",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1422f28826d2a0c11e5240b3e951c9e214d8656e",
              "lessThan": "3764627b30a283e611e652c4a2bb8cdc74a75a99",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1422f28826d2a0c11e5240b3e951c9e214d8656e",
              "lessThan": "6d0c8b7073913011459cf968cbbadd341e166bc3",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "bec6c4ce1169a565c58c347d5d0ac22e46d507d6",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "f781fb5177cdfd9a6c98cd94e30275457c6461ac",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "917135195200e20e5244b9c3f2bb40f3d5e02510",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d792459a6e2ae21c7f5107babd63e52e4c5ab93a",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "5.10.214",
              "lessThan": "5.10.271",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "5.15.153",
              "lessThan": "5.15.222",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "6.1.83",
              "lessThan": "6.1.189",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "6.6.23",
              "lessThan": "6.6.158",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "4.19.311",
              "lessThan": "4.20",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "5.4.273",
              "lessThan": "5.5",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "6.7.11",
              "lessThan": "6.8",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "6.8.2",
              "lessThan": "6.9",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "net/rds/send.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.9",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.9",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.10.271",
              "lessThanOrEqual": "5.10.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.15.222",
              "lessThanOrEqual": "5.15.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.189",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.158",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.111",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.53",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.7",
              "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/3764627b30a283e611e652c4a2bb8cdc74a75a99",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/3d401934b7edb3ccb07d982dabadd04c45ee307c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/5a806ed1eb46850ca4159a18b2a8c4b70f0c1341",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/6d0c8b7073913011459cf968cbbadd341e166bc3",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/6f552364d97cf4005c7a58f11c9f79e14e269865",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/a269795107f45adc95975a83324f8fef40bec4ce",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/a94b1dfc82454c5bc068e71c25393af674daf63b",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ed7ee0cd0e136d02f87f13181b1a89880463c7e9",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}