In the Linux kernel, the following vulnerability has been resolved:
bpf: Allow delete from sockmap/sockhash only if update is allowed
We have seen an influx of syzkaller reports where a BPF program attached to a tracepoint triggers a locking rule violation by performing a map_delete on a sockmap/sockhash.
We don't intend to support this artificial use scenario. Extend the existing verifier allowed-program-type check for updating sockmap/sockhash to also cover deleting from a map.
From now on only BPF programs which were previously allowed to update sockmap/sockhash can delete from these map types.
Exploitability
AV:LAC:HPR:LUI:NScope
S:UImpact
C:NI:HA:N4.7/CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N