# CVE-2023-53347: net/mlx5: Handle pairing of E-switch via uplink un/load APIs CVE-2023-53347 is fixed in linux on 1 platform, first by DEBIAN-CVE-2023-53347, released September 17, 2025. It is not reported as exploited. Patch Radar priority: Routine. - Web page: https://patchblox.com/security/cve/CVE-2023-53347 - Priority: Routine - CVSS: 5.5 (Moderate) - EPSS: 0.0021 - CISA KEV: not listed - Exploited (vendor report): no - Publicly disclosed: no - Published: Sep 17, 2025 - Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-53347 ## Description In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Handle pairing of E-switch via uplink un/load APIs In case user switch a device from switchdev mode to legacy mode, mlx5 first unpair the E-switch and afterwards unload the uplink vport. From the other hand, in case user remove or reload a device, mlx5 first unload the uplink vport and afterwards unpair the E-switch. The latter is causing a bug[1], hence, handle pairing of E-switch as part of uplink un/load APIs. [1] In case VF_LAG is used, every tc fdb flow is duplicated to the peer esw. However, the original esw keeps a pointer to this duplicated flow, not the peer esw. e.g.: if user create tc fdb flow over esw0, the flow is duplicated over esw1, in FW/HW, but in SW, esw0 keeps a pointer to the duplicated flow. During module unload while a peer tc fdb flow is still offloaded, in case the first device to be removed is the peer device (esw1 in the example above), the peer net-dev is destroyed, and so the mlx5e_priv is memset to 0. Afterwards, the peer device is trying to unpair himself from the original device (esw0 in the example above). Unpair API invoke the original device to clear peer flow from its eswitch (esw0), but the peer flow, which is stored over the original eswitch (esw0), is trying to use the peer mlx5e_priv, which is memset to 0 and result in bellow kernel-oops. [ 157.964081 ] BUG: unable to handle page fault for address: 000000000002ce60 [ 157.964662 ] #PF: supervisor read access in kernel mode [ 157.965123 ] #PF: error_code(0x0000) - not-present page [ 157.965582 ] PGD 0 P4D 0 [ 157.965866 ] Oops: 0000 [#1] SMP [ 157.967670 ] RIP: 0010:mlx5e_tc_del_fdb_flow+0x48/0x460 [mlx5_core] [ 157.976164 ] Call Trace: [ 157.976437 ] [ 157.976690 ] __mlx5e_tc_del_fdb_peer_flow+0xe6/0x100 [mlx5_core] [ 157.977230 ] mlx5e_tc_clean_fdb_peer_flows+0x67/0x90 [mlx5_core] [ 157.977767 ] mlx5_esw_offloads_unpair+0x2d/0x1e0 [mlx5_core] [ 157.984653 ] mlx5_esw_offloads_devcom_event+0xbf/0x130 [mlx5_core] [ 157.985212 ] mlx5_devcom_send_event+0xa3/0xb0 [mlx5_core] [ 157.985714 ] esw_offloads_disable+0x5a/0x110 [mlx5_core] [ 157.986209 ] mlx5_eswitch_disable_locked+0x152/0x170 [mlx5_core] [ 157.986757 ] mlx5_eswitch_disable+0x51/0x80 [mlx5_core] [ 157.987248 ] mlx5_unload+0x2a/0xb0 [mlx5_core] [ 157.987678 ] mlx5_uninit_one+0x5f/0xd0 [mlx5_core] [ 157.988127 ] remove_one+0x64/0xe0 [mlx5_core] [ 157.988549 ] pci_device_remove+0x31/0xa0 [ 157.988933 ] device_release_driver_internal+0x18f/0x1f0 [ 157.989402 ] driver_detach+0x3f/0x80 [ 157.989754 ] bus_remove_driver+0x70/0xf0 [ 157.990129 ] pci_unregister_driver+0x34/0x90 [ 157.990537 ] mlx5_cleanup+0xc/0x1c [mlx5_core] [ 157.990972 ] __x64_sys_delete_module+0x15a/0x250 [ 157.991398 ] ? exit_to_user_mode_prepare+0xea/0x110 [ 157.991840 ] do_syscall_64+0x3d/0x90 [ 157.992198 ] entry_SYSCALL_64_after_hwframe+0x46/0xb0 ## Where it's fixed | Platform | Product | Fixed in | Fix | Released | |---|---|---|---|---| | Linux | linux Debian 12.15 (bookworm) | 6.1.37-1 | [DEBIAN-CVE-2023-53347](https://patchblox.com/security/data/fix/linux/debian-cve-2023-53347.md) | Sep 17, 2025 | | Linux | linux Debian 13.5 (trixie) | 6.3.7-1 | [DEBIAN-CVE-2023-53347](https://patchblox.com/security/data/fix/linux/debian-cve-2023-53347.md) | Sep 17, 2025 | | Linux | linux Debian 14 | 6.3.7-1 | [DEBIAN-CVE-2023-53347](https://patchblox.com/security/data/fix/linux/debian-cve-2023-53347.md) | Sep 17, 2025 | --- Data as of 2026-11-08T06:59:42Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.