In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
net\/sched: drr: clamp quantum in change class<\/p>\n
drr_change_class() rejects explicit quantum==0 but falls back to
\npsched_mtu() with no floor. With a crafted size table qdisc_pkt_len
\nreaches ~2 GiB, so quantum=1 (or a zero psched_mtu on a headerless
\ndevice) makes the deficit-refill loop spin under the qdisc lock.<\/p>\n
Add clamp_t(u32, quantum, 256, 1<<20) after the zero reject and on the
\nfallback path. The explicit-zero reject is preserved.<\/p>\n
Conditions to recreate the bug:
\n CONFIG_NET_SCH_DRR=y. Requires CAP_NET_ADMIN (namespace-local via
\n unshare -Urn suffices).<\/p>\n
tc qdisc add dev dummy0 root drr
\n tc class add dev dummy0 parent 1: classid 1:1 drr quantum 1<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
net\/sched: drr: clamp quantum in change class<\/p>\n
drr_change_class() rejects explicit quantum==0 but falls back to
\npsched_mtu() with n<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-29165","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/29165","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=29165"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=29165"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=29165"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}