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Fencer Vulns
high 7.8

CVE-2024-43880 json

mlxsw: spectrum_acl_erp: Fix object nesting warning

published 2024-08-21 2 y ago modified 2026-08-05 3 mo ago also EUVD-2024-40530

cvss
7.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 13%
public exploits
0
none known

Summary

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

mlxsw: spectrum_acl_erp: Fix object nesting warning

ACLs in Spectrum-2 and newer ASICs can reside in the algorithmic TCAM (A-TCAM) or in the ordinary circuit TCAM (C-TCAM). The former can contain more ACLs (i.e., tc filters), but the number of masks in each region (i.e., tc chain) is limited.

In order to mitigate the effects of the above limitation, the device allows filters to share a single mask if their masks only differ in up to 8 consecutive bits. For example, dst_ip/25 can be represented using dst_ip/24 with a delta of 1 bit. The C-TCAM does not have a limit on the number of masks being used (and therefore does not support mask aggregation), but can contain a limited number of filters.

The driver uses the "objagg" library to perform the mask aggregation by passing it objects that consist of the filter's mask and whether the filter is to be inserted into the A-TCAM or the C-TCAM since filters in different TCAMs cannot share a mask.

The set of created objects is dependent on the insertion order of the filters and is not necessarily optimal. Therefore, the driver will periodically ask the library to compute a more optimal set ("hints") by looking at all the existing objects.

When the library asks the driver whether two objects can be aggregated the driver only compares the provided masks and ignores the A-TCAM / C-TCAM indication. This is the right thing to do since the goal is to move as many filters as possible to the A-TCAM. The driver also forbids two identical masks from being aggregated since this can only happen if one was intentionally put in the C-TCAM to avoid a conflict in the A-TCAM.

The above can result in the following set of hints:

H1: {mask X, A-TCAM} -> H2: {mask Y, A-TCAM} // X is Y + delta H3: {mask Y, C-TCAM} -> H4: {mask Z, A-TCAM} // Y is Z + delta

After getting the hints from the library the driver will start migrating filters from one region to another while consulting the computed hints and instructing the device to perform a lookup in both regions during the transition.

Assuming a filter with mask X is being migrated into the A-TCAM in the new region, the hints lookup will return H1. Since H2 is the parent of H1, the library will try to find the object associated with it and create it if necessary in which case another hints lookup (recursive) will be performed. This hints lookup for {mask Y, A-TCAM} will either return H2 or H3 since the driver passes the library an object comparison function that ignores the A-TCAM / C-TCAM indication.

This can eventually lead to nested objects which are not supported by the library [1].

Fix by removing the object comparison function from both the driver and the library as the driver was the only user. That way the lookup will only return exact matches.

I do not have a reliable reproducer that can reproduce the issue in a timely manner, but before the fix the issue would reproduce in several minutes and with the fix it does not reproduce in over an hour.

Note that the current usefulness of the hints is limited because they include the C-TCAM indication and represent aggregation that cannot actually happen. This will be addressed in net-next.

[1] WARNING: CPU: 0 PID: 153 at lib/objagg.c:170 objagg_obj_parent_assign+0xb5/0xd0 Modules linked in: CPU: 0 PID: 153 Comm: kworker/0:18 Not tainted 6.9.0-rc6-custom-g70fbc2c1c38b #42 Hardware name: Mellanox Technologies Ltd. MSN3700C/VMOD0008, BIOS 5.11 10/10/2018 Workqueue: mlxsw_core mlxsw_sp_acl_tcam_vregion_rehash_work RIP: 0010:objagg_obj_parent_assign+0xb5/0xd0 [...] Call Trace: <TASK> __objagg_obj_get+0x2bb/0x580 objagg_obj_get+0xe/0x80 mlxsw_sp_acl_erp_mask_get+0xb5/0xf0 mlxsw_sp_acl_atcam_entry_add+0xe8/0x3c0 mlxsw_sp_acl_tcam_entry_create+0x5e/0xa0 mlxsw_sp_acl_tcam_vchunk_migrate_one+0x16b/0x270 mlxsw_sp_acl_tcam_vregion_rehash_work+0xbe/0x510 process_one_work+0x151/0x370

Patch / fix

  • Linux Linux 5.4.282, 5.10.224, 5.15.165, 6.1.103, 6.6.44, 6.10.3, 6.11
  • linux Debian 12 6.1.106-1
  • linux Debian 14, Debian 13 6.10.3-1

debian advisories DEBIAN-CVE-2024-43880

  • linux Ubuntu 20.04 LTS 5.4.0-200.220
  • linux Ubuntu 22.04 LTS 5.15.0-125.135
  • linux Ubuntu 24.04 LTS 6.8.0-50.51
  • linux-aws Ubuntu 20.04 LTS 5.4.0-1135.145
  • linux-aws Ubuntu 22.04 LTS 5.15.0-1072.78
  • linux-aws Ubuntu 24.04 LTS 6.8.0-1020.22
  • linux-gcp Ubuntu 20.04 LTS 5.4.0-1139.148
  • linux-gcp Ubuntu 22.04 LTS 5.15.0-1071.79

ubuntu advisories UBUNTU-CVE-2024-43880

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • kernel-rt RHEL 8 4.18.0-553.27.1.rt7.368.el8_10
  • kernel-rt-kvm RHEL 8 4.18.0-553.27.1.rt7.368.el8_10
  • kernel-rt-core RHEL 8 4.18.0-553.27.1.rt7.368.el8_10
  • kernel-rt-modules RHEL 8 4.18.0-553.27.1.rt7.368.el8_10
  • kernel-rt-debug-kvm RHEL 8 4.18.0-553.27.1.rt7.368.el8_10
  • kernel-rt-debug-core RHEL 8 4.18.0-553.27.1.rt7.368.el8_10
  • kernel-rt-debug-modules RHEL 8 4.18.0-553.27.1.rt7.368.el8_10
  • kernel-rt-modules-extra RHEL 8 4.18.0-553.27.1.rt7.368.el8_10

red hat advisories RHSA-2025:10701RHSA-2024:8870RHSA-2024:8856

  • kernel-rt Linux Micro 6.0 6.4.0-10.1
  • kernel-source-rt Linux Micro 6.0 6.4.0-10.1
  • kernel-livepatch-MICRO-6-0-RT_Update_2 Linux Micro 6.0 1-1.1
  • kernel-source Linux Micro 6.0 6.4.0-19.1
  • kernel-default Linux Micro 6.0 6.4.0-19.1
  • kernel-kvmsmall Linux Micro 6.0 6.4.0-19.1
  • kernel-default-base Linux Micro 6.0 6.4.0-17.1.1.51
  • kernel-livepatch-MICRO-6-0_Update_2 Linux Micro 6.0 1-1.1

suse advisories SUSE-SU-2025:20047-1SUSE-SU-2025:20044-1SUSE-SU-2024:3483-1SUSE-SU-2024:3383-1SUSE-SU-2024:3209-1SUSE-SU-2024:3195-1

  • kernel AlmaLinux 8 4.18.0-553.27.1.el8_10
  • perf AlmaLinux 8 4.18.0-553.27.1.el8_10
  • bpftool AlmaLinux 8 4.18.0-553.27.1.el8_10
  • kernel-core AlmaLinux 8 4.18.0-553.27.1.el8_10
  • kernel-tools AlmaLinux 8 4.18.0-553.27.1.el8_10
  • python3-perf AlmaLinux 8 4.18.0-553.27.1.el8_10
  • kernel-modules AlmaLinux 8 4.18.0-553.27.1.el8_10
  • kernel-zfcpdump AlmaLinux 8 4.18.0-553.27.1.el8_10

almalinux advisories ALSA-2024:8856ALSA-2024:8870

  • kernel-rt Rocky Linux 8 4.18.0-553.27.1.rt7.368.el8_10
  • kernel Rocky Linux 8 4.18.0-553.27.1.el8_10

rocky linux advisories RLSA-2024:8870RLSA-2024:8856

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2024-43880 updated cvss 4.7

kernel: mlxsw: spectrum_acl_erp: Fix object nesting warning

  • Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more
    affected: workaround, no fix available, no fix planned “Will not fix”
  • Red Hat CodeReady Linux Builder EUS (v.9.4) libperf 5.14.0-427.76.1.el9_4, kernel-debuginfo-common-s390x 5.14.0-427.76.1.el9_4, kernel-debuginfo-common-x86_64 5.14.0-427.76.1.el9_4, kernel-debuginfo-common-aarch64 5.14.0-427.76.1.el9_4, kernel-debuginfo-common-ppc64le 5.14.0-427.76.1.el9_4 Red Hat Enterprise Linux AppStream EUS (v.9.4) rv 5.14.0-427.76.1.el9_4, perf 5.14.0-427.76.1.el9_4, rtla 5.14.0-427.76.1.el9_4, kernel-devel-matched 5.14.0-427.76.1.el9_4, kernel-64k-devel-matched 5.14.0-427.76.1.el9_4, kernel-debug-devel-matched 5.14.0-427.76.1.el9_4, +6 more
    fixed: vendor fix RHSA-2025:10701
  • Red Hat Enterprise Linux BaseOS (v. 8) perf 4.18.0-553.27.1.el8_10, kernel 4.18.0-553.27.1.el8_10, bpftool 4.18.0-553.27.1.el8_10, kernel-core 4.18.0-553.27.1.el8_10, kernel-tools 4.18.0-553.27.1.el8_10, python3-perf 4.18.0-553.27.1.el8_10, +15 more
    fixed: vendor fix RHSA-2024:8856
  • Red Hat Enterprise Linux BaseOS EUS (v.9.4) bpftool 7.3.0-427.76.1.el9_4, kernel 5.14.0-427.76.1.el9_4, kernel-64k 5.14.0-427.76.1.el9_4, kernel-core 5.14.0-427.76.1.el9_4, kernel-tools 5.14.0-427.76.1.el9_4, python3-perf 5.14.0-427.76.1.el9_4, +28 more
    fixed: vendor fix RHSA-2025:10701
  • Red Hat Enterprise Linux CRB (v. 8) kernel-debuginfo-common-x86_64 4.18.0-553.27.1.el8_10, kernel-debuginfo-common-aarch64 4.18.0-553.27.1.el8_10, kernel-debuginfo-common-ppc64le 4.18.0-553.27.1.el8_10
    fixed: vendor fix RHSA-2024:8856
  • Red Hat Enterprise Linux NFV (v. 8) kernel-rt 4.18.0-553.27.1.rt7.368.el8_10, kernel-rt-kvm 4.18.0-553.27.1.rt7.368.el8_10, kernel-rt-core 4.18.0-553.27.1.rt7.368.el8_10, kernel-rt-modules 4.18.0-553.27.1.rt7.368.el8_10, kernel-rt-debug-kvm 4.18.0-553.27.1.rt7.368.el8_10, kernel-rt-debug-core 4.18.0-553.27.1.rt7.368.el8_10, +4 more
    fixed: vendor fix RHSA-2024:8870
  • Red Hat Enterprise Linux Real Time EUS (v.9.4) kernel-rt 5.14.0-427.76.1.el9_4, kernel-rt-core 5.14.0-427.76.1.el9_4, kernel-rt-modules 5.14.0-427.76.1.el9_4, kernel-rt-debug-core 5.14.0-427.76.1.el9_4, kernel-rt-modules-core 5.14.0-427.76.1.el9_4, kernel-rt-debug-modules 5.14.0-427.76.1.el9_4, +4 more Red Hat Enterprise Linux Real Time for NFV EUS (v.9.4) kernel-rt 5.14.0-427.76.1.el9_4, kernel-rt-kvm 5.14.0-427.76.1.el9_4, kernel-rt-core 5.14.0-427.76.1.el9_4, kernel-rt-modules 5.14.0-427.76.1.el9_4, kernel-rt-debug-kvm 5.14.0-427.76.1.el9_4, kernel-rt-debug-core 5.14.0-427.76.1.el9_4, +6 more
    fixed: vendor fix RHSA-2025:10701
  • Red Hat Enterprise Linux RT (v. 8) kernel-rt 4.18.0-553.27.1.rt7.368.el8_10, kernel-rt-core 4.18.0-553.27.1.rt7.368.el8_10, kernel-rt-modules 4.18.0-553.27.1.rt7.368.el8_10, kernel-rt-debug-core 4.18.0-553.27.1.rt7.368.el8_10, kernel-rt-debug-modules 4.18.0-553.27.1.rt7.368.el8_10, kernel-rt-modules-extra 4.18.0-553.27.1.rt7.368.el8_10, +2 more
    fixed: vendor fix RHSA-2024:8870
show 1 more
  • Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

cisa ICSA-25-226-07 updated

Siemens Third-Party Components in SINEC OS

  • Siemens RUGGEDCOM RST2428P (6GK6242-6PA00) Siemens SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 family Siemens SCALANCE XCM-/XRM-/XCH-/XRH-300 family
    not affected

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

cisa ICSA-25-226-15 updated cvss 5.5

Siemens SINEC OS

  • Siemens RUGGEDCOM RST2428P (6GK6242-6PA00) < 3.1 Siemens SCALANCE XCM-/XRM-/XCH-/XRH-300 family < 3.1
    affected: fixed in V3.1 support.industry.siemens.com
  • Siemens SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 family
    not affected

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
2 y ago

Exploit prediction

0.23% chance of exploitation in the next 30 days, higher than 13% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected products

  • Linux Linux

Classification

Weakness
  • CWE-401 Missing Release of Memory after Effective Lifetime
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.