CVE-2026-99262
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: io_uring/timeout: don't lose a cancel as io-wq arms a timeout An IORING_OP_TIMEOUT run by io-wq, because of IOSQE_ASYNC, has the same problem as poll, futex and waitid. io_wq_submit_work() looks at IO_WQ_WORK_CANCEL once, before it issues the request. A cancel in between flags the work, gets -EALREADY, and searches ->timeout_list in vain, while the worker then adds the request and starts the timer: io-wq worker io_try_cancel() io_wq_submit_work() IO_WQ_WORK_CANCEL isn't set io_async_cancel_one() sets IO_WQ_WORK_CANCEL = -EALREADY io_timeout_cancel() = -ENOENT io_timeout() adds the request to ->timeout_list hrtimer_start() = IOU_ISSUE_SKIP_COMPLETE Nobody looks at the flag again, and the timeout runs its course. At ring exit, io_uring_try_cancel_requests() cancels io-wq work and then kills the timeouts the same way, so an exiting task can get stuck for the full duration of such a timeout. Look at the flag under ->timeout_lock, which the search takes as well, and fail the request if it is set. If the search came first, the flag is visible. If it comes later, it finds the request on the list.
View original CVE JSON
{
"id": "CVE-2026-99262",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-11-03T12:17:33.210",
"lastModified": "2026-11-03T12:17:33.210",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/timeout: don't lose a cancel as io-wq arms a timeout\n\nAn IORING_OP_TIMEOUT run by io-wq, because of IOSQE_ASYNC, has the same\nproblem as poll, futex and waitid. io_wq_submit_work() looks at\nIO_WQ_WORK_CANCEL once, before it issues the request. A cancel in between\nflags the work, gets -EALREADY, and searches ->timeout_list in vain,\nwhile the worker then adds the request and starts the timer:\n\n io-wq worker io_try_cancel()\n io_wq_submit_work()\n IO_WQ_WORK_CANCEL isn't set\n io_async_cancel_one()\n sets IO_WQ_WORK_CANCEL\n = -EALREADY\n io_timeout_cancel() = -ENOENT\n io_timeout()\n adds the request to ->timeout_list\n hrtimer_start()\n = IOU_ISSUE_SKIP_COMPLETE\n\nNobody looks at the flag again, and the timeout runs its course. At ring\nexit, io_uring_try_cancel_requests() cancels io-wq work and then kills\nthe timeouts the same way, so an exiting task can get stuck for the full\nduration of such a timeout.\n\nLook at the flag under ->timeout_lock, which the search takes as well,\nand fail the request if it is set. If the search came first, the flag is\nvisible. If it comes later, it finds the request on the list."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"io_uring/io_uring.h",
"io_uring/timeout.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "ce35a47a3a0208a77b4d31b7f2e8ed57d624093d",
"lessThan": "f1fabf17f37b252b11d8fe5c70c8056b70b005ca",
"versionType": "git",
"status": "affected"
},
{
"version": "ce35a47a3a0208a77b4d31b7f2e8ed57d624093d",
"lessThan": "68cd06ba918d9658c36c1973a0184795738dcc46",
"versionType": "git",
"status": "affected"
},
{
"version": "ce35a47a3a0208a77b4d31b7f2e8ed57d624093d",
"lessThan": "f9d5e02649587885852f46b6dc7c081b87f0ac3a",
"versionType": "git",
"status": "affected"
},
{
"version": "ce35a47a3a0208a77b4d31b7f2e8ed57d624093d",
"lessThan": "f10ab47077e63d6eee35b242c257c3947bb49e64",
"versionType": "git",
"status": "affected"
},
{
"version": "ce35a47a3a0208a77b4d31b7f2e8ed57d624093d",
"lessThan": "df705a274da10da7bb546e08b49fa80a6ef19c78",
"versionType": "git",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"io_uring/io_uring.h",
"io_uring/timeout.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "5.6",
"status": "affected"
},
{
"version": "0",
"lessThan": "5.6",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.1.191",
"lessThanOrEqual": "6.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.6.161",
"lessThanOrEqual": "6.6.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.12.115",
"lessThanOrEqual": "6.12.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18.60",
"lessThanOrEqual": "6.18.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.2.14",
"lessThanOrEqual": "7.2.*",
"versionType": "semver",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {},
"references": [
{
"url": "https://git.kernel.org/stable/c/68cd06ba918d9658c36c1973a0184795738dcc46",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/df705a274da10da7bb546e08b49fa80a6ef19c78",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/f10ab47077e63d6eee35b242c257c3947bb49e64",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/f1fabf17f37b252b11d8fe5c70c8056b70b005ca",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/f9d5e02649587885852f46b6dc7c081b87f0ac3a",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
]
}