<Vulnerability name="CVE-2026-53285">
    <DocumentDistribution xml:lang="en">Copyright © 2012 Red Hat, Inc. All rights reserved.</DocumentDistribution>
    <ThreatSeverity>Low</ThreatSeverity>
    <PublicDate>2026-06-26T00:00:00</PublicDate>
    <Bugzilla id="2493717" url="https://bugzilla.redhat.com/show_bug.cgi?id=2493717" xml:lang="en:us">
kernel: drm/amd/display: Wrap DCN32 phantom-plane allocation in DC_RUN_WITH_PREEMPTION_ENABLED
    </Bugzilla>
    <CVSS3 status="draft">
        <CVSS3BaseScore>5.5</CVSS3BaseScore>
        <CVSS3ScoringVector>CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H</CVSS3ScoringVector>
    </CVSS3>
    <CWE>CWE-663</CWE>
    <Details xml:lang="en:us" source="Mitre">
In the Linux kernel, the following vulnerability has been resolved:

drm/amd/display: Wrap DCN32 phantom-plane allocation in DC_RUN_WITH_PREEMPTION_ENABLED

[Why]
dcn32_validate_bandwidth() wraps dcn32_internal_validate_bw() with
DC_FP_START()/DC_FP_END(). In x86 non-RT, DC_FP_START takes fpregs_lock(),
which disables local softirqs.

The DML1 path through dcn32_enable_phantom_plane() calls kvzalloc() to
allocate ~335 KiB for dc_plane_state. This triggers the vmalloc path,
which calls BUG_ON(in_interrupt()) because it's invoked within the
FPU-enabled (softirq disabled) region, leading to a kernel crash.

[How]
Wrap the dc_state_create_phantom_plane() call with the
DC_RUN_WITH_PREEMPTION_ENABLED() macro to allow preemption during
this memory allocation.

(cherry picked from commit 885ccbef7b94a8b38f69c4211c679021aa27ad11)
    </Details>
    <Details xml:lang="en:us" source="Red Hat">
A flaw was found in the Linux kernel's `drm/amd/display` component. When the `dcn32_enable_phantom_plane()` function attempts to allocate memory using `kvzalloc()` within a floating-point unit (FPU) enabled region where software interrupts (softirqs) are disabled, it can trigger an error. This can lead to a kernel crash, resulting in a denial of service (DoS) for the system.
    </Details>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:10">
        <ProductName>Red Hat Enterprise Linux 10</ProductName>
        <FixState>Fix deferred</FixState>
        <PackageName>kernel</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:6">
        <ProductName>Red Hat Enterprise Linux 6</ProductName>
        <FixState>Out of support scope</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>Fix deferred</FixState>
        <PackageName>kernel</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:8">
        <ProductName>Red Hat Enterprise Linux 8</ProductName>
        <FixState>Fix deferred</FixState>
        <PackageName>kernel-rt</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:9">
        <ProductName>Red Hat Enterprise Linux 9</ProductName>
        <FixState>Fix deferred</FixState>
        <PackageName>kernel</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:9">
        <ProductName>Red Hat Enterprise Linux 9</ProductName>
        <FixState>Fix deferred</FixState>
        <PackageName>kernel-rt</PackageName>
    </PackageState>
    <References xml:lang="en:us">
https://www.cve.org/CVERecord?id=CVE-2026-53285
https://nvd.nist.gov/vuln/detail/CVE-2026-53285
https://lore.kernel.org/linux-cve-announce/2026062615-CVE-2026-53285-c33f@gregkh/T
    </References>
</Vulnerability>