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FKIE_CVE-2026-80889

Vulnerability from fkie_nvd - Published: 2026-09-04 18:17 - Updated: 2026-09-04 18:17
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved: can: isotp: fix timer drain order, wakeup handling and tx_gen ordering This patch is a follow-up to commit cf070fe33bfb ("can: isotp: serialize TX state transitions under so->rx_lock") which addresses following sashiko-bot findings: - isotp_sendmsg(): drain so->txfrtimer first so a stale callback can't re-arm echotimer after the claim - isotp_release(): wake so->wait after forcing ISOTP_SHUTDOWN so a sleeping sendmsg() claim isn't stranded - isotp_sendmsg(): have both wait_event_interruptible() calls in isotp_sendmsg() also wake on ISOTP_SHUTDOWN and do not return claim to IDLE to avoid corrupting a concurrent isotp_release() process. - isotp_sendmsg(): handle potential claim of a new transfer when the wait_event_interruptible() call returns in CAN_ISOTP_WAIT_TX_DONE mode. Don't touch timers and states of the new transfer if a new thread incremented so->tx_gen before getting the lock at err_event_drop. - isotp_sendmsg(): handle a stuck can_send() and omit timer and state changes if a new transfer was claimed. wait_tx_done() returns the error recorded in so->tx_result[], tagged with the caller's own generation. - isotp_tx_timeout(): on a claimed timeout, record the ECOMM error for the timed-out transfer's own generation in so->tx_result[]; sk->sk_err is raised unconditionally, same as every other error path here. - isotp_tx_gen_done()/isotp_tx_timeout(): always read tx.state (acquire) before tx_gen - the reverse order let a weakly ordered CPU pair a fresh tx.state with a stale tx_gen/tx_result slot. - isotp_sendmsg(): wait_tx_done: drain sk_err via sock_error() once we have read the result from so->tx_result[], so an already-reported error doesn't stay latched for a later poll()/SO_ERROR. Also align the remaining lock-free so->tx.state/rx.state/cfecho accesses and use skb->hash as unique loopback echo frame indicator.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/050f010f920da17c1044a4f174766ad553e770b6
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/10be509fa8fd95d1e47d40d1f68b0b26dfe9d572
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/2753722612d8824d3910096f93059f669009b0f0
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/35c62ac98d06669aa3f0f38b7829eaca929a611e
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/8acab9fc66d6f426c36968c91a979f70784945a7
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/af7e25c649ed68cbad07f8185af0f31b892cbf29
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/bf5c4a8b24acb12739ebb9aea5510b007e4f5239
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/deca7746b57d982cd4f0301f4443f56780c4a048
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/can/isotp.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "8acab9fc66d6f426c36968c91a979f70784945a7",
              "status": "affected",
              "version": "bbedeb67a9a684f2fb78c55bd3662c400526715e",
              "versionType": "git"
            },
            {
              "lessThan": "af7e25c649ed68cbad07f8185af0f31b892cbf29",
              "status": "affected",
              "version": "377a8f500704da42ed86a4541ed930e9dcfdb2ea",
              "versionType": "git"
            },
            {
              "lessThan": "2753722612d8824d3910096f93059f669009b0f0",
              "status": "affected",
              "version": "6da8119e8dd542194103139812d1a4b7dcd1aedd",
              "versionType": "git"
            },
            {
              "lessThan": "bf5c4a8b24acb12739ebb9aea5510b007e4f5239",
              "status": "affected",
              "version": "0b05eca9589f609e2491b528dccf683168a4cda8",
              "versionType": "git"
            },
            {
              "lessThan": "deca7746b57d982cd4f0301f4443f56780c4a048",
              "status": "affected",
              "version": "a7d90e7b5e75d7406c889fe36e9a61ee364a00cb",
              "versionType": "git"
            },
            {
              "lessThan": "10be509fa8fd95d1e47d40d1f68b0b26dfe9d572",
              "status": "affected",
              "version": "37beb16e08cae94cc05840c7274225e3b0b38ae7",
              "versionType": "git"
            },
            {
              "lessThan": "35c62ac98d06669aa3f0f38b7829eaca929a611e",
              "status": "affected",
              "version": "4f1fdf1a1c317bcac0c6b6c8e12642c9983de1ca",
              "versionType": "git"
            },
            {
              "lessThan": "050f010f920da17c1044a4f174766ad553e770b6",
              "status": "affected",
              "version": "cf070fe33bfbd1a4c21236078fadb35dd223a157",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/can/isotp.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "5.10.267",
              "status": "affected",
              "version": "5.10.265",
              "versionType": "semver"
            },
            {
              "lessThan": "5.15.218",
              "status": "affected",
              "version": "5.15.216",
              "versionType": "semver"
            },
            {
              "lessThan": "6.1.185",
              "status": "affected",
              "version": "6.1.183",
              "versionType": "semver"
            },
            {
              "lessThan": "6.6.151",
              "status": "affected",
              "version": "6.6.148",
              "versionType": "semver"
            },
            {
              "lessThan": "6.12.103",
              "status": "affected",
              "version": "6.12.101",
              "versionType": "semver"
            },
            {
              "lessThan": "6.18.44",
              "status": "affected",
              "version": "6.18.40",
              "versionType": "semver"
            },
            {
              "lessThan": "7.1.8",
              "status": "affected",
              "version": "7.1.5",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncan: isotp: fix timer drain order, wakeup handling and tx_gen ordering\n\nThis patch is a follow-up to commit cf070fe33bfb (\"can: isotp: serialize\nTX state transitions under so-\u003erx_lock\") which addresses following\nsashiko-bot findings:\n\n- isotp_sendmsg(): drain so-\u003etxfrtimer first so a stale callback can\u0027t\n  re-arm echotimer after the claim\n\n- isotp_release(): wake so-\u003ewait after forcing ISOTP_SHUTDOWN so a\n  sleeping sendmsg() claim isn\u0027t stranded\n\n- isotp_sendmsg(): have both wait_event_interruptible() calls in\n  isotp_sendmsg() also wake on ISOTP_SHUTDOWN and do not return claim to\n  IDLE to avoid corrupting a concurrent isotp_release() process.\n\n- isotp_sendmsg(): handle potential claim of a new transfer when\n  the wait_event_interruptible() call returns in CAN_ISOTP_WAIT_TX_DONE\n  mode. Don\u0027t touch timers and states of the new transfer if a new thread\n  incremented so-\u003etx_gen before getting the lock at err_event_drop.\n\n- isotp_sendmsg(): handle a stuck can_send() and omit timer and state\n  changes if a new transfer was claimed. wait_tx_done() returns the error\n  recorded in so-\u003etx_result[], tagged with the caller\u0027s own generation.\n\n- isotp_tx_timeout(): on a claimed timeout, record the ECOMM error for\n  the timed-out transfer\u0027s own generation in so-\u003etx_result[]; sk-\u003esk_err\n  is raised unconditionally, same as every other error path here.\n\n- isotp_tx_gen_done()/isotp_tx_timeout(): always read tx.state (acquire)\n  before tx_gen - the reverse order let a weakly ordered CPU pair a fresh\n  tx.state with a stale tx_gen/tx_result slot.\n\n- isotp_sendmsg(): wait_tx_done: drain sk_err via sock_error() once we\n  have read the result from so-\u003etx_result[], so an already-reported error\n  doesn\u0027t stay latched for a later poll()/SO_ERROR.\n\nAlso align the remaining lock-free so-\u003etx.state/rx.state/cfecho accesses\nand use skb-\u003ehash as unique loopback echo frame indicator."
    }
  ],
  "id": "CVE-2026-80889",
  "lastModified": "2026-09-04T18:17:56.910",
  "metrics": {},
  "published": "2026-09-04T18:17:56.910",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/050f010f920da17c1044a4f174766ad553e770b6"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/10be509fa8fd95d1e47d40d1f68b0b26dfe9d572"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/2753722612d8824d3910096f93059f669009b0f0"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/35c62ac98d06669aa3f0f38b7829eaca929a611e"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/8acab9fc66d6f426c36968c91a979f70784945a7"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/af7e25c649ed68cbad07f8185af0f31b892cbf29"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/bf5c4a8b24acb12739ebb9aea5510b007e4f5239"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/deca7746b57d982cd4f0301f4443f56780c4a048"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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