CVE-2026-64510ACPI: NFIT: core: Fix acpi_nfit_init() error cleanup

Official description

In the Linux kernel, the following vulnerability has been resolved: ACPI: NFIT: core: Fix acpi_nfit_init() error cleanup If acpi_nfit_init() fails after adding the acpi_desc object to the acpi_descs list, that object is never removed from that list because the acpi_nfit_shutdown() devm action is not added for the NFIT device in that case. Next, the acpi_nfit_init() failure causes acpi_nfit_probe() to fail, the acpi_desc object is freed, and a dangling pointer is left behind in the acpi_descs. Any subsequent ACPI Machine Check Exception will trigger nfit_handle_mce() which iterates over acpi_descs and so a use-after-free will occur. Moreover, if acpi_nfit_probe() returns 0 after installing a notify handler for the NFIT device and without allocating the acpi_desc object and setting the NFIT device's driver data pointer, the acpi_desc object will be allocated by acpi_nfit_update_notify() and acpi_nfit_init() will be called to initialize it. Regardless of whether or not acpi_nfit_init() fails in that case, the acpi_nfit_shutdown() devm action is not added for the NFIT device and acpi_desc is never removed from the acpi_descs list. If the acpi_desc object is freed subsequently on driver removal, any subsequent ACPI MCE will lead to a use-after-free like in the previous case. To address the first issue mentioned above, make acpi_nfit_probe() call acpi_nfit_shutdown() directly on acpi_nfit_init() failures and to address the other one, add a remove callback to the driver and make it call acpi_nfit_shutdown(). Also, since it is now possible to pass NULL to acpi_nfit_shutdown() or the acpi_desc object passed to it may not have been initialized, add checks against NULL for acpi_desc and its nvdimm_bus field to that function and make acpi_nfit_unregister() clear the latter after unregistering the NVDIMM bus.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/ee82078e776ae31266cc70fdf62ac17c3c6f100a
• https://git.kernel.org/stable/c/6ff054cc02a763914773b026cacb429e5fbf64fa
• https://git.kernel.org/stable/c/b07d22a2d17ad6465c87bd5752bc70e4c16e0ee4
• https://git.kernel.org/stable/c/c127dbd832bd4b9aef8a749d9f491b74042f9b47
• https://git.kernel.org/stable/c/df7c92216a1583a76cb0cbf2f21cd68870609b05
• https://git.kernel.org/stable/c/3b2628f7682aea8d9ce09ad4b9a3bd144b451eaa
• https://git.kernel.org/stable/c/7d69235bdc581a4346e9bcd6a8bea37d3e1abd25
• https://git.kernel.org/stable/c/38bf27511ef41bffebd157ec3eba41fc89ba59cd