In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: Avoid unregistering PSP twice
PSP is unregistered twice in:
_mlx5e_remove -> mlx5e_psp_unregister
mlx5e_nic_cleanup -> mlx5e_psp_unregister
This leads to a refcount underflow in some conditions:
------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 2 PID: 1694 at lib/refcount.c:28 refcount_warn_saturate+0xd8/0xe0
[...]
mlx5e_psp_unregister+0x26/0x50 [mlx5_core]
mlx5e_nic_cleanup+0x26/0x90 [mlx5_core]
mlx5e_remove+0xe6/0x1f0 [mlx5_core]
auxiliary_bus_remove+0x18/0x30
device_release_driver_internal+0x194/0x1f0
bus_remove_device+0xc6/0x130
device_del+0x159/0x3c0
mlx5_rescan_drivers_locked+0xbc/0x2a0 [mlx5_core]
[...]
Do not directly remove psp from the _mlx5e_remove path, the PSP cleanup
happens as part of profile cleanup.
