CVE-2025-39936
crypto: ccp - Always pass in an error pointer to __sev_platform_shutdown_locked()
Description
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.
INFO
Published Date :
Oct. 4, 2025, 8:15 a.m.
Last Modified :
Oct. 6, 2025, 2:56 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
- Apply the patch to the Linux kernel.
- Ensure error pointers are passed correctly.
- Compile and install the updated kernel.
- Reboot the system after updating.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2025-39936.
| URL | Resource |
|---|---|
| https://git.kernel.org/stable/c/46834d90a9a13549264b9581067d8f746b4b36cc | |
| https://git.kernel.org/stable/c/bc509293c9d4f4f74e776f4a0bbb61f63c041938 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2025-39936 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2025-39936
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2025-39936 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2025-39936 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Oct. 04, 2025
Action Type Old Value New Value Added Description 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. Added Reference https://git.kernel.org/stable/c/46834d90a9a13549264b9581067d8f746b4b36cc Added Reference https://git.kernel.org/stable/c/bc509293c9d4f4f74e776f4a0bbb61f63c041938