Linux Kernel up to 5.15.114/6.1.30/6.3.4 mlx5e deadlock

Summaryinfo

A vulnerability was found in Linux Kernel up to 5.15.114/6.1.30/6.3.4. It has been classified as critical. This affects an unknown function of the component mlx5e. This manipulation causes deadlock. This vulnerability is registered as CVE-2023-53591. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability classified as critical was found in Linux Kernel up to 5.15.114/6.1.30/6.3.4. Affected by this vulnerability is an unknown code block of the component mlx5e. The manipulation with an unknown input leads to a deadlock vulnerability. The CWE definition for the vulnerability is CWE-833. The product contains multiple threads or executable segments that are waiting for each other to release a necessary lock, resulting in deadlock. As an impact it is known to affect availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix deadlock in tc route query code Cited commit causes ABBA deadlock[0] when peer flows are created while holding the devcom rw semaphore. Due to peer flows offload implementation the lock is taken much higher up the call chain and there is no obvious way to easily fix the deadlock. Instead, since tc route query code needs the peer eswitch structure only to perform a lookup in xarray and doesn't perform any sleeping operations with it, refactor the code for lockless execution in following ways: - RCUify the devcom 'data' pointer. When resetting the pointer synchronously wait for RCU grace period before returning. This is fine since devcom is currently only used for synchronization of pairing/unpairing of eswitches which is rare and already expensive as-is. - Wrap all usages of 'paired' boolean in {READ|WRITE}_ONCE(). The flag has already been used in some unlocked contexts without proper annotations (e.g. users of mlx5_devcom_is_paired() function), but it wasn't an issue since all relevant code paths checked it again after obtaining the devcom semaphore. Now it is also used by mlx5_devcom_get_peer_data_rcu() as "best effort" check to return NULL when devcom is being unpaired. Note that while RCU read lock doesn't prevent the unpaired flag from being changed concurrently it still guarantees that reader can continue to use 'data'. - Refactor mlx5e_tc_query_route_vport() function to use new mlx5_devcom_get_peer_data_rcu() API which fixes the deadlock. [0]: [ 164.599612] ====================================================== [ 164.600142] WARNING: possible circular locking dependency detected [ 164.600667] 6.3.0-rc3+ #1 Not tainted [ 164.601021] ------------------------------------------------------ [ 164.601557] handler1/3456 is trying to acquire lock: [ 164.601998] ffff88811f1714b0 (&esw->offloads.encap_tbl_lock){+.+.}-{3:3}, at: mlx5e_attach_encap+0xd8/0x8b0 [mlx5_core] [ 164.603078] but task is already holding lock: [ 164.603617] ffff88810137fc98 (&comp->sem){++++}-{3:3}, at: mlx5_devcom_get_peer_data+0x37/0x80 [mlx5_core] [ 164.604459] which lock already depends on the new lock. [ 164.605190] the existing dependency chain (in reverse order) is: [ 164.605848] -> #1 (&comp->sem){++++}-{3:3}: [ 164.606380] down_read+0x39/0x50 [ 164.606772] mlx5_devcom_get_peer_data+0x37/0x80 [mlx5_core] [ 164.607336] mlx5e_tc_query_route_vport+0x86/0xc0 [mlx5_core] [ 164.607914] mlx5e_tc_tun_route_lookup+0x1a4/0x1d0 [mlx5_core] [ 164.608495] mlx5e_attach_decap_route+0xc6/0x1e0 [mlx5_core] [ 164.609063] mlx5e_tc_add_fdb_flow+0x1ea/0x360 [mlx5_core] [ 164.609627] __mlx5e_add_fdb_flow+0x2d2/0x430 [mlx5_core] [ 164.610175] mlx5e_configure_flower+0x952/0x1a20 [mlx5_core] [ 164.610741] tc_setup_cb_add+0xd4/0x200 [ 164.611146] fl_hw_replace_filter+0x14c/0x1f0 [cls_flower] [ 164.611661] fl_change+0xc95/0x18a0 [cls_flower] [ 164.612116] tc_new_tfilter+0x3fc/0xd20 [ 164.612516] rtnetlink_rcv_msg+0x418/0x5b0 [ 164.612936] netlink_rcv_skb+0x54/0x100 [ 164.613339] netlink_unicast+0x190/0x250 [ 164.613746] netlink_sendmsg+0x245/0x4a0 [ 164.614150] sock_sendmsg+0x38/0x60 [ 164.614522] ____sys_sendmsg+0x1d0/0x1e0 [ 164.614934] ___sys_sendmsg+0x80/0xc0 [ 164.615320] __sys_sendmsg+0x51/0x90 [ 164.615701] do_syscall_64+0x3d/0x90 [ 164.616083] entry_SYSCALL_64_after_hwframe+0x46/0xb0 [ 164.616568] -> #0 (&esw->offloads.encap_tbl_lock){+.+.}-{3:3}: [ 164.617210] __lock_acquire+0x159e/0x26e0 [ 164.617638] lock_acquire+0xc2/0x2a0 [ 164.618018] __mutex_lock+0x92/0xcd0 [ 164.618401] mlx5e_attach_encap+0xd8/0x8b0 [mlx5_core] [ 164.618943] post_process_attr+0x153/0x2d0 [ ---truncated---

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2023-53591 since 10/04/2025. The exploitation appears to be difficult. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 5.15.115, 6.1.31 or 6.3.5 eliminates this vulnerability. Applying the patch 69966bce28da6aadccfd968b75d128a79da32d17/362063df6ceec80b0b6798b61ae03504dcc125a5/a7236e420a7d8082b1df4b3e05c739dd2642a662/691c041bf20899fc13c793f92ba61ab660fa3a30 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at EUVD (EUVD-2023-60017) and CERT Bund (WID-SEC-2025-2194). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Google Container-Optimized OS
• Debian Linux
• Google Cloud Platform
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• Open Source Linux Kernel
• RESF Rocky Linux
• NetApp ActiveIQ Unified Manager
• IBM QRadar SIEM
• Dell NetWorker

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.15.114
• 6.1.0
• 6.1.1
• 6.1.2
• 6.1.3
• 6.1.4
• 6.1.5
• 6.1.6
• 6.1.7
• 6.1.8
• 6.1.9
• 6.1.10
• 6.1.11
• 6.1.12
• 6.1.13
• 6.1.14
• 6.1.15
• 6.1.16
• 6.1.17
• 6.1.18
• 6.1.19
• 6.1.20
• 6.1.21
• 6.1.22
• 6.1.23
• 6.1.24
• 6.1.25
• 6.1.26
• 6.1.27
• 6.1.28
• 6.1.29
• 6.1.30
• 6.3.0
• 6.3.1
• 6.3.2
• 6.3.3
• 6.3.4

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Exploitinginfo

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Entryinfo

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