---
id: CVE-2025-39936
title: >-
  In the Linux kernel, the following vulnerability has been resolved:


  crypto: ccp - Always pass in an error pointer to
  __sev_platform_shutdown_locked()


  When

    9770b428b1a2 ("crypto: ccp - Move dev_info/err messages for SEV/SNP init and …
summary: >-
  In the Linux kernel, the following vulnerability has been resolved:


  crypto: ccp - Always pass in an error pointer to
  __sev_platform_shutdown_locked()


  When

    9770b428b1a2 ("crypto: ccp - Move dev_info/err messages for SEV/SNP init and …
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-476
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 6.16, < 6.16.9'
  - linux_kernel = 6.17
patched:
  - linux_kernel 6.16.9
published: '2025-10-04'
updated: '2026-07-24'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-39936'
references:
  - url: 'https://git.kernel.org/stable/c/46834d90a9a13549264b9581067d8f746b4b36cc'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/bc509293c9d4f4f74e776f4a0bbb61f63c041938'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/fa30d62ab62d8a123f20febaca4390525e2d2ad5'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
epss: 0.00143
epssPercentile: 0.02958
ingestedAt: '2026-07-24T15:30:57.958Z'
---

## Overview

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

crypto: ccp - Always pass in an error pointer to __sev_platform_shutdown_locked()

When

  9770b428b1a2 ("crypto: ccp - Move dev_info/err messages for SEV/SNP init and shutdown")

moved the error messages dumping so that they don't need to be issued by
the callers, it missed the case where __sev_firmware_shutdown() calls
__sev_platform_shutdown_locked() with a NULL argument which leads to
a NULL ptr deref on the shutdown path, during suspend to disk:

  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 0 P4D 0
  Oops: Oops: 0000 [#1] SMP NOPTI
  CPU: 0 UID: 0 PID: 983 Comm: hib.sh Not tainted 6.17.0-rc4+ #1 PREEMPT(voluntary)
  Hardware name: Supermicro Super Server/H12SSL-i, BIOS 2.5 09/08/2022
  RIP: 0010:__sev_platform_shutdown_locked.cold+0x0/0x21 [ccp]

That rIP is:

  00000000000006fd <__sev_platform_shutdown_locked.cold>:
   6fd:   8b 13                   mov    (%rbx),%edx
   6ff:   48 8b 7d 00             mov    0x0(%rbp),%rdi
   703:   89 c1                   mov    %eax,%ecx

  Code: 74 05 31 ff 41 89 3f 49 8b 3e 89 ea 48 c7 c6 a0 8e 54 a0 41 bf 92 ff ff ff e8 e5 2e 09 e1 c6 05 2a d4 38 00 01 e9 26 af ff ff <8b> 13 48 8b 7d 00 89 c1 48 c7 c6 18 90 54 a0 89 44 24 04 e8 c1 2e
  RSP: 0018:ffffc90005467d00 EFLAGS: 00010282
  RAX: 00000000ffffff92 RBX: 0000000000000000 RCX: 0000000000000000
  			     ^^^^^^^^^^^^^^^^
and %rbx is nice and clean.

  Call Trace:
   <TASK>
   __sev_firmware_shutdown.isra.0
   sev_dev_destroy
   psp_dev_destroy
   sp_destroy
   pci_device_shutdown
   device_shutdown
   kernel_power_off
   hibernate.cold
   state_store
   kernfs_fop_write_iter
   vfs_write
   ksys_write
   do_syscall_64
   entry_SYSCALL_64_after_hwframe

Pass in a pointer to the function-local error var in the caller.

With that addressed, suspending the ccp shows the error properly at
least:

  ccp 0000:47:00.1: sev command 0x2 timed out, disabling PSP
  ccp 0000:47:00.1: SEV: failed to SHUTDOWN error 0x0, rc -110
  SEV-SNP: Leaking PFN range 0x146800-0x146a00
  SEV-SNP: PFN 0x146800 unassigned, dumping non-zero entries in 2M PFN region: [0x146800 - 0x146a00]
  ...
  ccp 0000:47:00.1: SEV-SNP firmware shutdown failed, rc -16, error 0x0
  ACPI: PM: Preparing to enter system sleep state S5
  kvm: exiting hardware virtualization
  reboot: Power down

Btw, this driver is crying to be cleaned up to pass in a proper I/O
struct which can be used to store information between the different
functions, otherwise stuff like that will happen in the future again.

## Affected

- `linux_kernel >= 6.16, < 6.16.9`
- `linux_kernel = 6.17`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.16.9`