CVE-2026-64244 PUBLISHED

drivers/base/memory: set mem->altmap after successful device registration

Assigner: Linux
Reserved: 19.07.2026 Published: 24.07.2026 Updated: 24.07.2026

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.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from 1a8c64e110435e44e71bcd50a75663174b575f22 to 802e113cf120df7208e4c7e604950a85e87120a8 (excl.)
  • affected from 1a8c64e110435e44e71bcd50a75663174b575f22 to 22dc0d042f02ce82aa61422ea5f232628bfd9e9c (excl.)
  • affected from 1a8c64e110435e44e71bcd50a75663174b575f22 to 6c25bf4e44a2b6a14332f952bba0974521f5b72d (excl.)
  • affected from 1a8c64e110435e44e71bcd50a75663174b575f22 to bc3dd82a0ffd488bb902f4c69c3d28fd4088d973 (excl.)
  • affected from 1a8c64e110435e44e71bcd50a75663174b575f22 to 059ac6252a63edf1cea79bf30bd860a8c264b62c (excl.)
  • affected from 1a8c64e110435e44e71bcd50a75663174b575f22 to a2b8d7827f48ee54a686cb80e4a1d0ff954ec42a (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 6.6 is affected
  • unaffected from 0 to 6.6 (excl.)
  • unaffected from 6.6.144 to 6.6.* (incl.)
  • unaffected from 6.12.95 to 6.12.* (incl.)
  • unaffected from 6.18.37 to 6.18.* (incl.)
  • unaffected from 7.0.14 to 7.0.* (incl.)
  • unaffected from 7.1.2 to 7.1.* (incl.)
  • unaffected from 7.2-rc1 to * (incl.)

References