In the Linux kernel, the following vulnerability has been resolved: bpf: Cancel the running bpf_timer through kworker for PREEMPT_RT During the update procedure, when overwrite element in a pre-all…

Summary

In the Linux kernel, the following vulnerability has been resolved: bpf: Cancel the running bpf_timer through kworker for PREEMPT_RT During the update procedure, when overwrite element in a pre-allocated htab, the freeing of old_element is protected by the bucket lock. The reason why the bucket lock is necessary is that the old_element has already been stashed in htab->extra_elems after alloc_htab_elem() returns. If freeing the old_element after the bucket lock is unlocked, the stashed elemen…