CVE-2026-64244

Summary

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.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux1a8c64e110435e44e71bcd50a75663174b575f22 < 802e113cf120df7208e4c7e604950a85e87120a8affected
LinuxLinux1a8c64e110435e44e71bcd50a75663174b575f22 < 22dc0d042f02ce82aa61422ea5f232628bfd9e9caffected
LinuxLinux1a8c64e110435e44e71bcd50a75663174b575f22 < 6c25bf4e44a2b6a14332f952bba0974521f5b72daffected
LinuxLinux1a8c64e110435e44e71bcd50a75663174b575f22 < bc3dd82a0ffd488bb902f4c69c3d28fd4088d973affected
LinuxLinux1a8c64e110435e44e71bcd50a75663174b575f22 < 059ac6252a63edf1cea79bf30bd860a8c264b62caffected
LinuxLinux1a8c64e110435e44e71bcd50a75663174b575f22 < a2b8d7827f48ee54a686cb80e4a1d0ff954ec42aaffected
LinuxLinux6.6affected
LinuxLinux0 < 6.6unaffected
LinuxLinux6.6.144 <= 6.6.*unaffected
LinuxLinux6.12.95 <= 6.12.*unaffected
LinuxLinux6.18.37 <= 6.18.*unaffected
LinuxLinux7.0.14 <= 7.0.*unaffected
LinuxLinux7.1.2 <= 7.1.*unaffected
LinuxLinux7.2-rc1 <= *unaffected

Weaknesses

References