CVE-2024-43874

Technical Description

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

crypto: ccp - Fix null pointer dereference in __sev_snp_shutdown_locked

Fix a null pointer dereference induced by DEBUG_TEST_DRIVER_REMOVE.

Return from __sev_snp_shutdown_locked() if the psp_device or the

sev_device structs are not initialized. Without the fix, the driver will

produce the following splat:

ccp 0000:55:00.5: enabling device (0000 -> 0002)

ccp 0000:55:00.5: sev enabled

ccp 0000:55:00.5: psp enabled

BUG: kernel NULL pointer dereference, address: 00000000000000f0

#PF: supervisor read access in kernel mode

#PF: error_code(0x0000) - not-present page

PGD 0 P4D 0

Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC NOPTI

CPU: 262 PID: 1 Comm: swapper/0 Not tainted 6.9.0-rc1+ #29

RIP: 0010:__sev_snp_shutdown_locked+0x2e/0x150

Code: 00 55 48 89 e5 41 57 41 56 41 54 53 48 83 ec 10 41 89 f7 49 89 fe 65 48 8b 04 25 28 00 00 00 48 89 45 d8 48 8b 05 6a 5a 7f 06 <4c> 8b a0 f0 00 00 00 41 0f b

Remediation

Check the references section for vendor advisories and patches from linux. Update linux_kernel to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

Affected Products

References