CVE-2026-64244
Published Jul 24, 2026
Description
In the Linux kernel, the following vulnerability has been resolved: drivers/base/memory: set mem->altmap after successful device registration If __add_memory_block() fails at xa_store() (under memory pressure for example), device_unregister() is called, which eventually triggers memory_block_release() with mem->altmap still set, causing a WARN_ON(mem->altmap). This was triggered by modifying virtio-mem driver. Fix this by delaying the assignment of mem->altmap until after __add_memory_block() has succeeded.
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References
Other References
https://git.kernel.org/stable/c/059ac6252a63edf1cea79bf30bd860a8c264b62c
https://git.kernel.org/stable/c/22dc0d042f02ce82aa61422ea5f232628bfd9e9c
https://git.kernel.org/stable/c/6c25bf4e44a2b6a14332f952bba0974521f5b72d
https://git.kernel.org/stable/c/802e113cf120df7208e4c7e604950a85e87120a8
https://git.kernel.org/stable/c/a2b8d7827f48ee54a686cb80e4a1d0ff954ec42a
https://git.kernel.org/stable/c/bc3dd82a0ffd488bb902f4c69c3d28fd4088d973
Frequently Asked Questions
What is CVE-2026-64244? +
In the Linux kernel, the following vulnerability has been resolved:
drivers/base/memory: set mem->altmap after successful device registration
If __add_memory_block() fails at xa_store() (under memory pressure for
example), device_unregister() is called, which eventually triggers
memory_block_release() with mem->altmap still set, causing a
WARN_ON(mem->altmap). This was triggered by modifying virtio-mem driver.
Fix this by delaying the assignment of mem->altmap until after
__add_memory_block() has succeeded.
How do I check if I'm vulnerable to CVE-2026-64244? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.