Bug 2493711 (CVE-2026-53314)

Summary: CVE-2026-53314 kernel: padata: Put CPU offline callback in ONLINE section to allow failure
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
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Priority: low    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
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OS: Linux   
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Description OSIDB Bzimport 2026-06-26 21:02:18 UTC
In the Linux kernel, the following vulnerability has been resolved:

padata: Put CPU offline callback in ONLINE section to allow failure

syzbot reported the following warning:

    DEAD callback error for CPU1
    WARNING: kernel/cpu.c:1463 at _cpu_down+0x759/0x1020 kernel/cpu.c:1463, CPU#0: syz.0.1960/14614

at commit 4ae12d8bd9a8 ("Merge tag 'kbuild-fixes-7.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux")
which tglx traced to padata_cpu_dead() given it's the only
sub-CPUHP_TEARDOWN_CPU callback that returns an error.

Failure isn't allowed in hotplug states before CPUHP_TEARDOWN_CPU
so move the CPU offline callback to the ONLINE section where failure is
possible.

Comment 1 Mauro Matteo Cascella 2026-06-29 20:19:39 UTC
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026062621-CVE-2026-53314-d913@gregkh/T