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CVE-2026-90081

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 rds_cong_map_updated() rds_cong_map_updated() runs after a peer's congestion map has been rewritten (by rds_tcp_cong_recv() and rds_ib_cong_recv(), or the clear-all in the loopback and IB send-completion paths). It bumps rds_cong_generation and then checks waitqueue_active() on map->m_waitq and on rds_poll_waitq to decide whether anyone needs waking. atomic_inc() carries no ordering and waitqueue_active() is a plain load, so nothing orders the map and generation stores before the wait queue reads. The waiters do the mirror image: rds_cong_wait() adds itself to m_waitq and then tests the port bit, and rds_poll() registers on rds_poll_waitq and then reads the generation. That is the store-buffering pattern described above waitqueue_active() in include/linux/wait.h - the updater can observe an empty wait queue while the waiter still observes the port as congested, and no wake-up is issued. rds_cong_wait() is an interruptible sleep with no timeout, so a sender blocked on a congested port stays blocked until the next congestion update from that peer arrives or a signal is delivered. A poll() waiter misses the map-updated notification the same way. Use wq_has_sleeper(), which is waitqueue_active() preceded by the required full barrier, as rds_tcp_state_change() already does for the same pattern.

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-17 17:16:57.423000
Last modified
2026-10-19 09:18:56.993000
View original CVE JSON
{
  "id": "CVE-2026-90081",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-17T17:16:57.423",
  "lastModified": "2026-10-19T09:18:56.993",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/rds: use wq_has_sleeper() in rds_cong_map_updated()\n\nrds_cong_map_updated() runs after a peer's congestion map has been\nrewritten (by rds_tcp_cong_recv() and rds_ib_cong_recv(), or the\nclear-all in the loopback and IB send-completion paths).  It bumps\nrds_cong_generation and then checks waitqueue_active() on\nmap->m_waitq and on rds_poll_waitq to decide whether anyone needs\nwaking.  atomic_inc() carries no ordering and waitqueue_active() is a\nplain load, so nothing orders the map and generation stores before\nthe wait queue reads.  The waiters do the mirror image: rds_cong_wait()\nadds itself to m_waitq and then tests the port bit, and rds_poll()\nregisters on rds_poll_waitq and then reads the generation.  That is\nthe store-buffering pattern described above waitqueue_active() in\ninclude/linux/wait.h - the updater can observe an empty wait queue\nwhile the waiter still observes the port as congested, and no wake-up\nis issued.\n\nrds_cong_wait() is an interruptible sleep with no timeout, so a\nsender blocked on a congested port stays blocked until the next\ncongestion update from that peer arrives or a signal is delivered.\nA poll() waiter misses the map-updated notification the same way.\n\nUse wq_has_sleeper(), which is waitqueue_active() preceded by the\nrequired full barrier, as rds_tcp_state_change() already does for\nthe same pattern."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "net/rds/cong.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "922cb17a5c812fcc9ebee249f4109db099896941",
              "lessThan": "2a809d7896dbf18e1ecfbdd930f71c9fc298b16d",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "922cb17a5c812fcc9ebee249f4109db099896941",
              "lessThan": "fa4b98e891fda28cc0638d809c6125ec63d8319d",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "922cb17a5c812fcc9ebee249f4109db099896941",
              "lessThan": "0e169f6a2adeb17b5577ed7e8abd642465bb50ec",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "922cb17a5c812fcc9ebee249f4109db099896941",
              "lessThan": "42884bd8b8fd023d6a610a695bd5ddd1d5dece17",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "922cb17a5c812fcc9ebee249f4109db099896941",
              "lessThan": "a526214b9f0548ca0e53a6e0d1727d8ea9befc23",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "922cb17a5c812fcc9ebee249f4109db099896941",
              "lessThan": "bf2b8130723efcb5b86c3ddb6317c3a9b2a9cfc5",
              "versionType": "git",
              "status": "affected"
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            {
              "version": "922cb17a5c812fcc9ebee249f4109db099896941",
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              "versionType": "git",
              "status": "affected"
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            {
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              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "net/rds/cong.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "2.6.30",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "2.6.30",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.10.270",
              "lessThanOrEqual": "5.10.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.15.221",
              "lessThanOrEqual": "5.15.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.188",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.157",
              "lessThanOrEqual": "6.6.*",
              "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/0e169f6a2adeb17b5577ed7e8abd642465bb50ec",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/281f9fda2e06d6c211bb365a5379ed2e05cc2e21",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/2a809d7896dbf18e1ecfbdd930f71c9fc298b16d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/42884bd8b8fd023d6a610a695bd5ddd1d5dece17",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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    {
      "url": "https://git.kernel.org/stable/c/a526214b9f0548ca0e53a6e0d1727d8ea9befc23",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/bf2b8130723efcb5b86c3ddb6317c3a9b2a9cfc5",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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    {
      "url": "https://git.kernel.org/stable/c/d4f484661961636eb90d287050959e613795f73a",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
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      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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}