CVE-2025-21883

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

ice: Fix deinitializing VF in error path

If ice_ena_vfs() fails after calling ice_create_vf_entries(), it frees
all VFs without removing them from snapshot PF-VF mailbox list, leading
to list corruption.

Reproducer:
  devlink dev eswitch set $PF1_PCI mode switchdev
  ip l s $PF1 up
  ip l s $PF1 promisc on
  sleep 1
  echo 1 > /sys/class/net/$PF1/device/sriov_numvfs
  sleep 1
  echo 1 > /sys/class/net/$PF1/device/sriov_numvfs

Trace (minimized):
  list_add corruption. next->prev should be prev (ffff8882e241c6f0), but was 0000000000000000. (next=ffff888455da1330).
  kernel BUG at lib/list_debug.c:29!
  RIP: 0010:__list_add_valid_or_report+0xa6/0x100
   ice_mbx_init_vf_info+0xa7/0x180 [ice]
   ice_initialize_vf_entry+0x1fa/0x250 [ice]
   ice_sriov_configure+0x8d7/0x1520 [ice]
   ? __percpu_ref_switch_mode+0x1b1/0x5d0
   ? __pfx_ice_sriov_configure+0x10/0x10 [ice]

Sometimes a KASAN report can be seen instead with a similar stack trace:
  BUG: KASAN: use-after-free in __list_add_valid_or_report+0xf1/0x100

VFs are added to this list in ice_mbx_init_vf_info(), but only removed
in ice_free_vfs(). Move the removing to ice_free_vf_entries(), which is
also being called in other places where VFs are being removed (including
ice_free_vfs() itself).