CVE: CVE-2023-54216
Published: 2025-12-30
Description: In the Linux kernel, the following vulnerability has been resolved:

net/mlx5e: TC, Fix using eswitch mapping in nic mode

Cited patch is using the eswitch object mapping pool while
in nic mode where it isn't initialized. This results in the
trace below [0].

Fix that by using either nic or eswitch object mapping pool
depending if eswitch is enabled or not.

[0]:
[  826.446057] ==================================================================
[  826.446729] BUG: KASAN: slab-use-after-free in mlx5_add_flow_rules+0x30/0x490 [mlx5_core]
[  826.447515] Read of size 8 at addr ffff[PII_REDACTED]30 by task tc/6233

[  826.448243] CPU: 16 PID: 6233 Comm: tc Tainted: G        W          6.3.0-rc6+ #1
[  826.448890] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
[  826.449785] Call Trace:
[  826.450052]  <TASK>
[  826.450302]  dump_stack_lvl+0x33/0x50
[  826.450650]  print_report+0xc2/0x610
[  826.450998]  ? __virt_addr_valid+0xb1/0x130
[  826.451385]  ? mlx5_add_flow_rules+0x30/0x490 [mlx5_core]
[  826.451935]  kasan_report+0xae/0xe0
[  826.452276]  ? mlx5_add_flow_rules+0x30/0x490 [mlx5_core]
[  826.452829]  mlx5_add_flow_rules+0x30/0x490 [mlx5_core]
[  826.453368]  ? __kmalloc_node+0x5a/0x120
[  826.453733]  esw_add_restore_rule+0x20f/0x270 [mlx5_core]
[  826.454288]  ? mlx5_eswitch_add_send_to_vport_meta_rule+0x260/0x260 [mlx5_core]
[  826.455011]  ? mutex_unlock+0x80/0xd0
[  826.455361]  ? __mutex_unlock_slowpath.constprop.0+0x210/0x210
[  826.455862]  ? mapping_add+0x2cb/0x440 [mlx5_core]
[  826.456425]  mlx5e_tc_action_miss_mapping_get+0x139/0x180 [mlx5_core]
[  826.457058]  ? mlx5e_tc_update_skb_nic+0xb0/0xb0 [mlx5_core]
[  826.457636]  ? __kasan_kmalloc+0x77/0x90
[  826.458000]  ? __kmalloc+0x57/0x120
[  826.458336]  mlx5_tc_ct_flow_offload+0x325/0xe40 [mlx5_core]
[  826.458916]  ? ct_kernel_enter.constprop.0+0x48/0xa0
[  826.459360]  ? mlx5_tc_ct_parse_action+0xf0/0xf0 [mlx5_core]
[  826.459933]  ? mlx5e_mod_hdr_attach+0x491/0x520 [mlx5_core]
[  826.460507]  ? mlx5e_mod_hdr_get+0x12/0x20 [mlx5_core]
[  826.461046]  ? mlx5e_tc_attach_mod_hdr+0x154/0x170 [mlx5_core]
[  826.461635]  mlx5e_configure_flower+0x969/0x2110 [mlx5_core]
[  826.462217]  ? _raw_spin_lock_bh+0x85/0xe0
[  826.462597]  ? __mlx5e_add_fdb_flow+0x750/0x750 [mlx5_core]
[  826.463163]  ? kasan_save_stack+0x2e/0x40
[  826.463534]  ? down_read+0x115/0x1b0
[  826.463878]  ? down_write_killable+0x110/0x110
[  826.464288]  ? tc_setup_action.part.0+0x9f/0x3b0
[  826.464701]  ? mlx5e_is_uplink_rep+0x4c/0x90 [mlx5_core]
[  826.465253]  ? mlx5e_tc_reoffload_flows_work+0x130/0x130 [mlx5_core]
[  826.465878]  tc_setup_cb_add+0x112/0x250
[  826.466247]  fl_hw_replace_filter+0x230/0x310 [cls_flower]
[  826.466724]  ? fl_hw_destroy_filter+0x1a0/0x1a0 [cls_flower]
[  826.467212]  fl_change+0x14e1/0x2030 [cls_flower]
[  826.467636]  ? sock_def_readable+0x89/0x120
[  826.468019]  ? fl_tmplt_create+0x2d0/0x2d0 [cls_flower]
[  826.468509]  ? kasan_unpoison+0x23/0x50
[  826.468873]  ? get_random_u16+0x180/0x180
[  826.469244]  ? __radix_tree_lookup+0x2b/0x130
[  826.469640]  ? fl_get+0x7b/0x140 [cls_flower]
[  826.470042]  ? fl_mask_put+0x200/0x200 [cls_flower]
[  826.470478]  ? __mutex_unlock_slowpath.constprop.0+0x210/0x210
[  826.470973]  ? fl_tmplt_create+0x2d0/0x2d0 [cls_flower]
[  826.471427]  tc_new_tfilter+0x644/0x1050
[  826.471795]  ? tc_get_tfilter+0x860/0x860
[  826.472170]  ? __thaw_task+0x130/0x130
[  826.472525]  ? arch_stack_walk+0x98/0xf0
[  826.472892]  ? cap_capable+0x9f/0xd0
[  826.473235]  ? security_capable+0x47/0x60
[  826.473608]  rtnetlink_rcv_msg+0x1d5/0x550
[  826.473985]  ? rtnl_calcit.isra.0+0x1f0/0x1f0
[  826.474383]  ? __stack_depot_save+0x35/0x4c0
[  826.474779]  ? kasan_save_stack+0x2e/0x40
[  826.475149]  ? kasan_save_stack+0x1e/0x40
[  826.475518]  ? __kasan_record_aux_stack+0x9f/0xb0
[  826.475939]  ? task_work_add+0x77/0x1c0
[  826.476305]  netlink_rcv_skb+0xe0/0x210
---truncated---
References: https://git.kernel.org/stable/c/4150441c010dec36abc389828e2e4758bd8ad4b3; https://git.kernel.org/stable/c/dfa1e46d6093831b9d49f0f350227a1d13644a2f