Bug 2373507 (CVE-2022-49975)

Summary: CVE-2022-49975 kernel: bpf: Don't redirect packets with invalid pkt_len
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
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Priority: low    
Version: unspecifiedCC: dfreiber, drow, jburrell, vkumar
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Hardware: All   
OS: Linux   
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Description OSIDB Bzimport 2025-06-18 12:06:01 UTC 
In the Linux kernel, the following vulnerability has been resolved:

bpf: Don't redirect packets with invalid pkt_len

Syzbot found an issue [1]: fq_codel_drop() try to drop a flow whitout any
skbs, that is, the flow->head is null.
The root cause, as the [2] says, is because that bpf_prog_test_run_skb()
run a bpf prog which redirects empty skbs.
So we should determine whether the length of the packet modified by bpf
prog or others like bpf_prog_test is valid before forwarding it directly.
Comment 1 Avinash Hanwate 2025-06-19 20:41:19 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2025061819-CVE-2022-49975-89e6@gregkh/T