Attacker Value
Unknown
(0 users assessed)
Exploitability
Unknown
(0 users assessed)
User Interaction
None
Privileges Required
Low
Attack Vector
Local
0

CVE-2024-56717

Disclosure Date: December 29, 2024 •
CVE-2024-56717 CVSS v3 Base Score: 5.5
Add MITRE ATT&CK tactics and techniques that apply to this CVE.

Description

In the Linux kernel, the following vulnerability has been resolved:

net: mscc: ocelot: fix incorrect IFH SRC_PORT field in ocelot_ifh_set_basic()

Packets injected by the CPU should have a SRC_PORT field equal to the
CPU port module index in the Analyzer block (ocelot->num_phys_ports).

The blamed commit copied the ocelot_ifh_set_basic() call incorrectly
from ocelot_xmit_common() in net/dsa/tag_ocelot.c. Instead of calling
with “x”, it calls with BIT_ULL(x), but the field is not a port mask,
but rather a single port index.

[ side note: this is the technical debt of code duplication :( ]

The error used to be silent and doesn’t appear to have other
user-visible manifestations, but with new changes in the packing
library, it now fails loudly as follows:

——————[ cut here ]——————
Cannot store 0x40 inside bits 46-43 – will truncate
sja1105 spi2.0: xmit timed out
WARNING: CPU: 1 PID: 102 at lib/packing.c:98 __pack+0x90/0x198
sja1105 spi2.0: timed out polling for tstamp
CPU: 1 UID: 0 PID: 102 Comm: felix_xmit
Tainted: G W N 6.13.0-rc1-00372-gf706b85d972d-dirty #2605
Call trace:
__pack+0x90/0x198 (P)
__pack+0x90/0x198 (L)
packing+0x78/0x98
ocelot_ifh_set_basic+0x260/0x368
ocelot_port_inject_frame+0xa8/0x250
felix_port_deferred_xmit+0x14c/0x258
kthread_worker_fn+0x134/0x350
kthread+0x114/0x138

The code path pertains to the ocelot switchdev driver and to the felix
secondary DSA tag protocol, ocelot-8021q. Here seen with ocelot-8021q.

The messenger (packing) is not really to blame, so fix the original
commit instead.

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CVSS V3 Severity and Metrics
Base Score:
5.5 Medium
Impact Score:
3.6
Exploitability Score:
1.8
Vector:
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector (AV):
Local
Attack Complexity (AC):
Low
Privileges Required (PR):
Low
User Interaction (UI):
None
Scope (S):
Unchanged
Confidentiality (C):
None
Integrity (I):
None
Availability (A):
High

General Information

Offensive Application
Unknown
Utility Class
Unknown
Ports
Unknown
OS
Unknown
Vulnerable Versions
Linux 59c4ca8d8d7918eb6e2df91d2c254827264be309
Linux 2f3c62ffe88116cd2a39cd73e01103535599970f
Linux a8836eae3288c351acd3b2743d2fad2a4ee2bd56
Linux not down converted
Prerequisites
Unknown
Discovered By
Unknown
PoC Author
Unknown
Metasploit Module
Unknown
Reporter
Unknown
Technical Analysis