CVE-2025-38193

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> net_sched: sch_sfq: reject invalid perturb period<br /> <br /> Gerrard Tai reported that SFQ perturb_period has no range check yet,<br /> and this can be used to trigger a race condition fixed in a separate patch.<br /> <br /> We want to make sure ctl-&gt;perturb_period * HZ will not overflow<br /> and is positive.<br /> <br /> <br /> tc qd add dev lo root sfq perturb -10 # negative value : error<br /> Error: sch_sfq: invalid perturb period.<br /> <br /> tc qd add dev lo root sfq perturb 1000000000 # too big : error<br /> Error: sch_sfq: invalid perturb period.<br /> <br /> tc qd add dev lo root sfq perturb 2000000 # acceptable value<br /> tc -s -d qd sh dev lo<br /> qdisc sfq 8005: root refcnt 2 limit 127p quantum 64Kb depth 127 flows 128 divisor 1024 perturb 2000000sec<br /> Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0)<br /> backlog 0b 0p requeues 0