CVE-2026-43306
Received Received - Intake
BPF Crypto Context Release Type Mismatch in Linux Kernel

Publication date: 2026-05-08

Last updated on: 2026-05-08

Assigner: kernel.org

Description
In the Linux kernel, the following vulnerability has been resolved: bpf: crypto: Use the correct destructor kfunc type With CONFIG_CFI enabled, the kernel strictly enforces that indirect function calls use a function pointer type that matches the target function. I ran into the following type mismatch when running BPF self-tests: CFI failure at bpf_obj_free_fields+0x190/0x238 (target: bpf_crypto_ctx_release+0x0/0x94; expected type: 0xa488ebfc) Internal error: Oops - CFI: 00000000f2008228 [#1] SMP ... As bpf_crypto_ctx_release() is also used in BPF programs and using a void pointer as the argument would make the verifier unhappy, add a simple stub function with the correct type and register it as the destructor kfunc instead.
CVSS Scores
EPSS Scores
Probability:
Percentile:
Meta Information
Published
2026-05-08
Last Modified
2026-05-08
Generated
2026-05-09
AI Q&A
2026-05-08
EPSS Evaluated
N/A
NVD
EUVD
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
linux linux_kernel *
Helpful Resources
Exploitability
CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-UNKNOWN
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?

This vulnerability is related to the Linux kernel's BPF (Berkeley Packet Filter) crypto subsystem. It involves the use of an incorrect destructor kernel function (kfunc) type when CONFIG_CFI (Control Flow Integrity) is enabled. The kernel enforces that indirect function calls must use a function pointer type matching the target function. A type mismatch was detected during BPF self-tests, causing a CFI failure and internal kernel error (Oops). The issue was that the function bpf_crypto_ctx_release was used with a void pointer argument, which the verifier did not accept. The fix involved adding a stub function with the correct type and registering it as the destructor kfunc.


How can this vulnerability impact me? :

This vulnerability can cause kernel crashes or internal errors due to type mismatches in function pointers when running BPF programs with CONFIG_CFI enabled. Such crashes can lead to system instability or denial of service conditions, impacting the reliability and availability of the affected Linux system.


Ask Our AI Assistant
Need more information? Ask your question to get an AI reply (Powered by our expertise)
0/70
EPSS Chart