In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
net\/sched: hhf: clamp quantum in change and init paths<\/p>\n
hhf_change() accepts any quantum from userspace, including 1. With a
\ncrafted size table qdisc_pkt_len reaches ~2 GiB, so quantum=1 makes
\nthe deficit-refill loop spin ~2^31 times under the qdisc lock
\n(a soft lockup \/ denial of service).<\/p>\n
Add max(256U, …) in hhf_change() matching fq_codel_change(). Clamp
\nhhf_init() to [256, 1<<20] matching the siblings, and remove the old
\nfallback that only set quantum=256 on overflow.<\/p>\n
Conditions to recreate the bug:
\n CONFIG_NET_SCH_HHF=y. Requires CAP_NET_ADMIN (namespace-local via
\n unshare -Urn suffices).<\/p>\n
tc qdisc add dev dummy0 root hhf
\n tc qdisc change dev dummy0 root hhf quantum 1 stab data 32768 size_log 15 cell_log 0<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
net\/sched: hhf: clamp quantum in change and init paths<\/p>\n
hhf_change() accepts any quantum from userspace, including 1. With a
\ncrafte<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-29166","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/29166","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln"}],"about":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/types\/vuln"}],"wp:attachment":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=29166"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=29166"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=29166"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}