net/mlx5e: TC, Check if flow is PEER before acquiring devcom lock (CVE-2026-80739) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-80739

net/mlx5e: TC, Check if flow is PEER before acquiring devcom lock

Answer in brief

CVE-2026-80739 records a Unknown severity vulnerability in net/mlx5e: TC, Check if flow is PEER before acquiring devcom lock. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 3, 2026Updated Sep 3, 2026Source checked Sep 3, 2026First seen by HOL Sep 3, 2026Material review Sep 3, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Linux/Linuxgeneric	>=04de7dda7394fa9c2b0fc9cec65661d9b4f0d04d <607adbda01053abf5f93e322fe39325da8828cb8 \|\| >=04de7dda7394fa9c2b0fc9cec65661d9b4f0d04d <585df8643081e6f616579bc52cd49ac823a57c82 \|\| >=04de7dda7394fa9c2b0fc9cec65661d9b4f0d04d <ff9e7d5e3500be389ce7a0e46db3a77149830bc9 \|\| >=04de7dda7394fa9c2b0fc9cec65661d9b4f0d04d <7165fe321c61ec138850c02f030f274797761f5f \|\| >=04de7dda7394fa9c2b0fc9cec65661d9b4f0d04d <6ddfba2ea98db21b001e0e5c472499156224650c	607adbda01053abf5f93e322fe39325da8828cb8, 585df8643081e6f616579bc52cd49ac823a57c82, ff9e7d5e3500be389ce7a0e46db3a77149830bc9, 7165fe321c61ec138850c02f030f274797761f5f, 6ddfba2ea98db21b001e0e5c472499156224650c
Linux/Linuxgeneric	5.0	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to 607adbda01053abf5f93e322fe39325da8828cb8 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 3, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 3, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 3, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: TC, Check if flow is PEER before acquiring devcom lock In case __mlx5e_add_fdb_flow() fails in lower levels, the flow is deleted via mlx5e_tc_del_flow(), and mlx5e_tc_del_flow() is acquiring ESW devcom lock without condition. In addition, in case of peer_flow, __mlx5e_add_fdb_flow() is called while holding ESW devcom comp lock. This results in an AA deadlock. To fix this, introduce a new PEER flag that is set on flows created as peer flows (the duplicate flows on peer devices), and check it in mlx5e_tc_del_flow() before acquiring ESW devcom lock. Lockdep splat: ============================================ WARNING: possible recursive locking detected ============================================ Possible unsafe locking scenario: CPU0 ---- lock(&comp->lock_key#2); lock(&comp->lock_key#2); *** DEADLOCK *** Call Trace: <TASK> dump_stack_lvl+0x69/0xa0 print_deadlock_bug.cold+0xbd/0xca __lock_acquire+0x1671/0x2ec0 lock_acquire+0x10e/0x2e0 down_read+0x95/0x430 mlx5_devcom_for_each_peer_begin+0x4e/0xe0 [mlx5_core] mlx5e_tc_del_flow+0x11d/0xa70 [mlx5_core] mlx5e_flow_put+0x99/0x100 [mlx5_core] __mlx5e_add_fdb_flow+0x409/0xf00 [mlx5_core] mlx5e_configure_flower+0x2a86/0x4100 [mlx5_core] mlx5e_rep_setup_tc_cls_flower+0x12f/0x1b0 [mlx5_core] mlx5e_rep_setup_tc_cb+0x153/0x750 [mlx5_core] tc_setup_cb_add+0x1dc/0x470 fl_change+0x2f4d/0x626d [cls_flower] tc_new_tfilter+0x79b/0x2310 rtnetlink_rcv_msg+0x778/0xad0 do_syscall_64+0x70/0x960 entry_SYSCALL_64_after_hwframe+0x4b/0x53 </TASK>

Quoted source text, attributed separately from HOL analysis.