Wind River Support Network

Description

In the Linux kernel, the following vulnerability has been resolved:EOL][EOL]net/sched: fix netdevice reference leaks in attach_default_qdiscs()[EOL][EOL]In attach_default_qdiscs(), if a dev has multiple queues and queue 0 fails[EOL]to attach qdisc because there is no memory in attach_one_default_qdisc().[EOL]Then dev->qdisc will be noop_qdisc by default. But the other queues may be[EOL]able to successfully attach to default qdisc.[EOL][EOL]In this case, the fallback to noqueue process will be triggered. If the[EOL]original attached qdisc is not released and a new one is directly[EOL]attached, this will cause netdevice reference leaks.[EOL][EOL]The following is the bug log:[EOL][EOL]veth0: default qdisc (fq_codel) fail, fallback to noqueue[EOL]unregister_netdevice: waiting for veth0 to become free. Usage count = 32[EOL]leaked reference.[EOL] qdisc_alloc+0x12e/0x210[EOL] qdisc_create_dflt+0x62/0x140[EOL] attach_one_default_qdisc.constprop.41+0x44/0x70[EOL] dev_activate+0x128/0x290[EOL] __dev_open+0x12a/0x190[EOL] __dev_change_flags+0x1a2/0x1f0[EOL] dev_change_flags+0x23/0x60[EOL] do_setlink+0x332/0x1150[EOL] __rtnl_newlink+0x52f/0x8e0[EOL] rtnl_newlink+0x43/0x70[EOL] rtnetlink_rcv_msg+0x140/0x3b0[EOL] netlink_rcv_skb+0x50/0x100[EOL] netlink_unicast+0x1bb/0x290[EOL] netlink_sendmsg+0x37c/0x4e0[EOL] sock_sendmsg+0x5f/0x70[EOL] ____sys_sendmsg+0x208/0x280[EOL][EOL]Fix this bug by clearing any non-noop qdiscs that may have been assigned[EOL]before trying to re-attach.

CREATE(Triage):(User=lchen-cn) [CVE-2022-49958 (https://nvd.nist.gov/vuln/detail/CVE-2022-49958)