Affected: Linux

In the Linux kernel, the following vulnerability has been resolved:

net/mlx5e: Don't call cleanup on profile rollback failure

When profile rollback fails in mlx5e_netdev_change_profile, the netdev profile var is left set to NULL. Avoid a crash when unloading the driver by not calling profile->cleanup in such a case.

This was encountered while testing, with the original trigger that the wq rescuer thread creation got interrupted (presumably due to Ctrl+C-ing modprobe), which gets converted to ENOMEM (-12) by mlx5e_priv_init, the profile rollback also fails for the same reason (signal still active) so the profile is left as NULL, leading to a crash later in _mlx5e_remove.

[ 732.473932] mlx5_core 0000:08:00.1: E-Switch: Unload vfs: mode(OFFLOADS), nvfs(2), necvfs(0), active vports(2) [ 734.525513] workqueue: Failed to create a rescuer kthread for wq "mlx5e": -EINTR [ 734.557372] mlx5_core 0000:08:00.1: mlx5e_netdev_init_profile:6235:(pid 6086): mlx5e_priv_init failed, err=-12 [ 734.559187] mlx5_core 0000:08:00.1 eth3: mlx5e_netdev_change_profile: new profile init failed, -12 [ 734.560153] workqueue: Failed to create a rescuer kthread for wq "mlx5e": -EINTR [ 734.589378] mlx5_core 0000:08:00.1: mlx5e_netdev_init_profile:6235:(pid 6086): mlx5e_priv_init failed, err=-12 [ 734.591136] mlx5_core 0000:08:00.1 eth3: mlx5e_netdev_change_profile: failed to rollback to orig profile, -12 [ 745.537492] BUG: kernel NULL pointer dereference, address: 0000000000000008 […