CVE-2024-56662

In the Linux kernel, the following vulnerability has been resolved:

acpi: nfit: vmalloc-out-of-bounds Read in acpi_nfit_ctl

Fix an issue detected by syzbot with KASAN:

BUG: KASAN: vmalloc-out-of-bounds in cmd_to_func drivers/acpi/nfit/ core.c:416 [inline] BUG: KASAN: vmalloc-out-of-bounds in acpi_nfit_ctl+0x20e8/0x24a0 drivers/acpi/nfit/core.c:459

The issue occurs in cmd_to_func when the call_pkg->nd_reserved2 array is accessed without verifying that call_pkg points to a buffer that is appropriately sized as a struct nd_cmd_pkg. This can lead to out-of-bounds access and undefined behavior if the buffer does not have sufficient space.

To address this, a check was added in acpi_nfit_ctl() to ensure that buf is not NULL and that buf_len is less than sizeof(*call_pkg) before accessing it. This ensures safe access to the members of call_pkg, including the nd_reserved2 array.

In order to touch the ioctl by a process it must be already running with root privileges as the device file is created with root privileges by the kernel. As a result, this bug can only be exploited if the attacker has existing credentials.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.