<Vulnerability name="CVE-2026-64425">
    <DocumentDistribution xml:lang="en">Copyright © 2012 Red Hat, Inc. All rights reserved.</DocumentDistribution>
    <PublicDate>2026-07-25T00:00:00</PublicDate>
    <Bugzilla id="2507171" url="https://bugzilla.redhat.com/show_bug.cgi?id=2507171" xml:lang="en:us">
kernel: io_uring/io-wq: re-check IO_WQ_BIT_EXIT for each linked work item
    </Bugzilla>
    <CWE>CWE-1050</CWE>
    <Details xml:lang="en:us" source="Mitre">
In the Linux kernel, the following vulnerability has been resolved:

io_uring/io-wq: re-check IO_WQ_BIT_EXIT for each linked work item

commit 10dc95939817 ("io_uring/io-wq: check IO_WQ_BIT_EXIT inside work
run loop") fixed the obvious case where io_worker_handle_work() took one
exit-bit snapshot before draining pending work, but the fix stops one
level too early.

io_worker_handle_work() now re-checks IO_WQ_BIT_EXIT in its outer work
run loop, yet it still snapshots that bit once before processing a whole
dependent linked-work chain. If io_wq_exit_start() sets IO_WQ_BIT_EXIT
after the first linked item has started, the remaining linked items can
still reuse stale do_kill = false, skip IO_WQ_WORK_CANCEL, and continue
running after exit has begun.

Move the check further inside, so it covers linked items too. Note: this
is a syzbot special as it loves setting up tons of slow linked work on
weird devices like msr that take forever to read, and immediately close
the ring. Exit then takes a long time.
    </Details>
    <Details xml:lang="en:us" source="Red Hat">
A flaw was found in the Linux kernel's `io_uring` subsystem. This vulnerability allows linked work items to continue executing even after a system exit process has begun. This can lead to a denial of service by prolonging the exit sequence and potentially consuming system resources unexpectedly.
    </Details>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:10">
        <ProductName>Red Hat Enterprise Linux 10</ProductName>
        <FixState>Not affected</FixState>
        <PackageName>kernel</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:6">
        <ProductName>Red Hat Enterprise Linux 6</ProductName>
        <FixState>Not affected</FixState>
        <PackageName>kernel</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:7">
        <ProductName>Red Hat Enterprise Linux 7</ProductName>
        <FixState>Not affected</FixState>
        <PackageName>kernel</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:7">
        <ProductName>Red Hat Enterprise Linux 7</ProductName>
        <FixState>Not affected</FixState>
        <PackageName>kernel-rt</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:8">
        <ProductName>Red Hat Enterprise Linux 8</ProductName>
        <FixState>Not affected</FixState>
        <PackageName>kernel</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:8">
        <ProductName>Red Hat Enterprise Linux 8</ProductName>
        <FixState>Not affected</FixState>
        <PackageName>kernel-rt</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:9">
        <ProductName>Red Hat Enterprise Linux 9</ProductName>
        <FixState>Not affected</FixState>
        <PackageName>kernel</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:9">
        <ProductName>Red Hat Enterprise Linux 9</ProductName>
        <FixState>Not affected</FixState>
        <PackageName>kernel-rt</PackageName>
    </PackageState>
    <References xml:lang="en:us">
https://www.cve.org/CVERecord?id=CVE-2026-64425
https://nvd.nist.gov/vuln/detail/CVE-2026-64425
https://lore.kernel.org/linux-cve-announce/2026072535-CVE-2026-64425-5940@gregkh/T
    </References>
</Vulnerability>