bpf: crypto: Use the correct destructor kfunc type
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.
02 / AFFECTED SOFTWARE
Affected packages
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
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.
05 / REFERENCES
Further evidence
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- https://git.kernel.org/stable/c/3979a550fe06b370d73647f59cf462fa525c9ec4
- https://git.kernel.org/stable/c/4e3e57dbf46dad3498f8c4219ce2dba756875962
- https://git.kernel.org/stable/c/50d6fd69388cc7b05dce72f09080674dcede4ac9
- https://git.kernel.org/stable/c/b40a5d724f29fc2eed23ff353808a9aae616b48a
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43306.json
- https://nvd.nist.gov/vuln/detail/CVE-2026-43306