CVE-2022-49975

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> bpf: Don&amp;#39;t redirect packets with invalid pkt_len<br /> <br /> Syzbot found an issue [1]: fq_codel_drop() try to drop a flow whitout any<br /> skbs, that is, the flow-&gt;head is null.<br /> The root cause, as the [2] says, is because that bpf_prog_test_run_skb()<br /> run a bpf prog which redirects empty skbs.<br /> So we should determine whether the length of the packet modified by bpf<br /> prog or others like bpf_prog_test is valid before forwarding it directly.