CVE-2026-98058: bpf: Mark syscall helpers as sleepable
bpf: Mark syscall helpers as sleepable
Affected Software
Event History
Frequently Asked Questions
Which systems are exposed to this issue?
Systems that run BPF programs of type BPF_PROG_TYPE_SYSCALL are exposed if those programs register BPF timer callbacks that can invoke the affected syscall helpers. The issue is specific to calls made from non-sleepable contexts such as hrtimer softirq context; calls from the sleepable syscall program body remain valid.
What is required to trigger the problem?
A BPF_PROG_TYPE_SYSCALL program must register a bpf_timer callback and have that callback invoke bpf_sys_bpf() or bpf_sys_close(). Because the callback is checked as non-sleepable while retaining the syscall helper set, the helper can sleep in an atomic context and cause a scheduling-while-atomic failure.
How does the fix prevent exploitation?
The fix marks bpf_sys_bpf() and bpf_sys_close() as helpers that might sleep. The existing helper-context validation then rejects their use from timer callbacks and other atomic, non-sleepable regions.