CVE-2024-56647

Public on 2024-12-27
Modified on 2025-01-03
Description
In the Linux kernel, the following vulnerability has been resolved:

net: Fix icmp host relookup triggering ip_rt_bug

arp link failure may trigger ip_rt_bug while xfrm enabled, call trace is:

WARNING: CPU: 0 PID: 0 at net/ipv4/route.c:1241 ip_rt_bug+0x14/0x20
Modules linked in:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.12.0-rc6-00077-g2e1b3cc9d7f7
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:ip_rt_bug+0x14/0x20
Call Trace:

ip_send_skb+0x14/0x40
__icmp_send+0x42d/0x6a0
ipv4_link_failure+0xe2/0x1d0
arp_error_report+0x3c/0x50
neigh_invalidate+0x8d/0x100
neigh_timer_handler+0x2e1/0x330
call_timer_fn+0x21/0x120
__run_timer_base.part.0+0x1c9/0x270
run_timer_softirq+0x4c/0x80
handle_softirqs+0xac/0x280
irq_exit_rcu+0x62/0x80
sysvec_apic_timer_interrupt+0x77/0x90

The script below reproduces this scenario:
ip xfrm policy add src 0.0.0.0/0 dst 0.0.0.0/0 \
dir out priority 0 ptype main flag localok icmp
ip l a veth1 type veth
ip a a 192.168.141.111/24 dev veth0
ip l s veth0 up
ping 192.168.141.155 -c 1

icmp_route_lookup() create input routes for locally generated packets
while xfrm relookup ICMP traffic.Then it will set input route
(dst->out = ip_rt_bug) to skb for DESTUNREACH.

For ICMP err triggered by locally generated packets, dst->dev of output
route is loopback. Generally, xfrm relookup verification is not required
on loopback interfaces (net.ipv4.conf.lo.disable_xfrm = 1).

Skip icmp relookup for locally generated packets to fix it.
Severity
Medium severity
Medium
CVSS v3 Base Score
5.5
See breakdown

Affected Packages

Platform Package Release Date Advisory Status
HAQM Linux 1 kernel No Fix Planned
HAQM Linux 2 - Core kernel Pending Fix
HAQM Linux 2 - Kernel-5.10 Extra kernel Pending Fix
HAQM Linux 2 - Kernel-5.15 Extra kernel Pending Fix
HAQM Linux 2 - Kernel-5.4 Extra kernel Pending Fix
HAQM Linux 2023 kernel Pending Fix

CVSS Scores

Score Type Score Vector
HAQM Linux CVSSv3 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD CVSSv3 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H