CVE-2021-47595: In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_ets: don't remove idle classes from the round-robin list Shuang reported…

PriorityP420medium5.5CVSS 3.1

AVLACLPRLUINSUCNINAH

EPSS

0.24%

15.0th percentile

In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_ets: don't remove idle classes from the round-robin list Shuang reported that the following script: 1) tc qdisc add dev ddd0 handle 10: parent 1: ets bands 8 strict 4 priomap 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 2) mausezahn ddd0 -A 10.10.10.1 -B 10.10.10.2 -c 0 -a own -b 00:c1:a0:c1:a0:00 -t udp & 3) tc qdisc change dev ddd0 handle 10: ets bands 4 strict 2 quanta 2500 2500 priomap 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 crashes systematically when line 2) is commented: list_del corruption, ffff8e028404bd30->next is LIST_POISON1 (dead000000000100) ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:47! invalid opcode: 0000 [#1] PREEMPT SMP NOPTI CPU: 0 PID: 954 Comm: tc Not tainted 5.16.0-rc4+ #478 Hardware name: Red Hat KVM, BIOS 1.11.1-4.module+el8.1.0+4066+0f1aadab 04/01/2014 RIP: 0010:__list_del_entry_valid.cold.1+0x12/0x47 Code: fe ff 0f 0b 48 89 c1 4c 89 c6 48 c7 c7 08 42 1b 87 e8 1d c5 fe ff 0f 0b 48 89 fe 48 89 c2 48 c7 c7 98 42 1b 87 e8 09 c5 fe ff 0b 48 c7 c7 48 43 1b 87 e8 fb c4 fe ff 0f 0b 48 89 f2 48 89 fe RSP: 0018:ffffae46807a3888 EFLAGS: 00010246 RAX: 000000000000004e RBX: 0000000000000007 RCX: 0000000000000202 RDX: 0000000000000000 RSI: ffffffff871ac536 RDI: 00000000ffffffff RBP: ffffae46807a3a10 R08: 0000000000000000 R09: c0000000ffff7fff R10: 0000000000000001 R11: ffffae46807a36a8 R12: ffff8e028404b800 R13: ffff8e028404bd30 R14: dead000000000100 R15: ffff8e02fafa2400 FS: 00007efdc92e4480(0000) GS:ffff8e02fb600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000682f48 CR3: 00000001058be000 CR4: 0000000000350ef0 Call Trace: ets_qdisc_change+0x58b/0xa70 [sch_ets] tc_modify_qdisc+0x323/0x880 rtnetlink_rcv_msg+0x169/0x4a0 netlink_rcv_skb+0x50/0x100 netlink_unicast+0x1a5/0x280 netlink_sendmsg+0x257/0x4d0 sock_sendmsg+0x5b/0x60 ____sys_sendmsg+0x1f2/0x260 ___sys_sendmsg+0x7c/0xc0 __sys_sendmsg+0x57/0xa0 do_syscall_64+0x

Affected

12 ranges

Vendor	Product	Version range	Fixed in
debian	linux	< linux 5.15.15-1 (bookworm)	linux 5.15.15-1 (bookworm)
linux	linux	>= 5.10.83 < 5.10.88	5.10.88
linux	linux	>= 5.15.6 < 5.15.11	5.15.11
linux	linux	>= ae2659d2c670252759ee9c823c4e039c0e05a6f2 < 81fbdd45652d8605a029e78ef14a6aaa529c4e72	81fbdd45652d8605a029e78ef14a6aaa529c4e72
linux	linux	>= de6d25924c2a8c2988c6a385990cafbe742061bf < c062f2a0b04d86c5b8c9d973bea43493eaca3d32	c062f2a0b04d86c5b8c9d973bea43493eaca3d32
linux	linux	>= e25bdbc7e951ae5728fee1f4c09485df113d013c < 491c1253441e2fdc8f6a6f4976e3f13440419b7a	491c1253441e2fdc8f6a6f4976e3f13440419b7a
linux	linux_kernel	>= 0 < 5.10.92-1	5.10.92-1
linux	linux_kernel	>= 0 < 5.15.15-1	5.15.15-1
linux	linux_kernel	>= 0 < 5.15.15-1	5.15.15-1
linux	linux_kernel	>= 0 < 5.15.15-1	5.15.15-1
linux	linux_kernel	>= 5.10.83 < 5.10.88	5.10.88
linux	linux_kernel	>= 5.15.6 < 5.15.11	5.15.11

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

osv5.5MEDIUM

vendor_debian5.5MEDIUM

vendor_redhat5.5MEDIUM

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