[Intel-wired-lan] [PATCH iwl-net 1/2] ice: Fix deinitializing VF in error path

[Marcin Szycik <marcin.szycik@linux.intel.com>]

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).

Fixes: 8cd8a6b17d27 ("ice: move VF overflow message count into struct ice_mbx_vf_info")
Reported-by: Sujai Buvaneswaran <sujai.buvaneswaran@intel.com>
Closes: https://lore.kernel.org/intel-wired-lan/PH0PR11MB50138B635F2E5CEB7075325D961F2@PH0PR11MB5013.namprd11.prod.outlook.com
Reviewed-by: Martyna Szapar-Mudlaw <martyna.szapar-mudlaw@linux.intel.com>
Signed-off-by: Marcin Szycik <marcin.szycik@linux.intel.com>
---
 drivers/net/ethernet/intel/ice/ice_sriov.c          | 5 +----
 drivers/net/ethernet/intel/ice/ice_vf_lib.c         | 8 ++++++++
 drivers/net/ethernet/intel/ice/ice_vf_lib_private.h | 1 +
 3 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_sriov.c b/drivers/net/ethernet/intel/ice/ice_sriov.c
index b83f99c01d91..8aabf7749aa5 100644
--- a/drivers/net/ethernet/intel/ice/ice_sriov.c
+++ b/drivers/net/ethernet/intel/ice/ice_sriov.c
@@ -36,6 +36,7 @@ static void ice_free_vf_entries(struct ice_pf *pf)
 
 	hash_for_each_safe(vfs->table, bkt, tmp, vf, entry) {
 		hash_del_rcu(&vf->entry);
+		ice_deinitialize_vf_entry(vf);
 		ice_put_vf(vf);
 	}
 }
@@ -193,10 +194,6 @@ void ice_free_vfs(struct ice_pf *pf)
 			wr32(hw, GLGEN_VFLRSTAT(reg_idx), BIT(bit_idx));
 		}
 
-		/* clear malicious info since the VF is getting released */
-		if (!ice_is_feature_supported(pf, ICE_F_MBX_LIMIT))
-			list_del(&vf->mbx_info.list_entry);
-
 		mutex_unlock(&vf->cfg_lock);
 	}
 
diff --git a/drivers/net/ethernet/intel/ice/ice_vf_lib.c b/drivers/net/ethernet/intel/ice/ice_vf_lib.c
index c7c0c2f50c26..815ad0bfe832 100644
--- a/drivers/net/ethernet/intel/ice/ice_vf_lib.c
+++ b/drivers/net/ethernet/intel/ice/ice_vf_lib.c
@@ -1036,6 +1036,14 @@ void ice_initialize_vf_entry(struct ice_vf *vf)
 	mutex_init(&vf->cfg_lock);
 }
 
+void ice_deinitialize_vf_entry(struct ice_vf *vf)
+{
+	struct ice_pf *pf = vf->pf;
+
+	if (!ice_is_feature_supported(pf, ICE_F_MBX_LIMIT))
+		list_del(&vf->mbx_info.list_entry);
+}
+
 /**
  * ice_dis_vf_qs - Disable the VF queues
  * @vf: pointer to the VF structure
diff --git a/drivers/net/ethernet/intel/ice/ice_vf_lib_private.h b/drivers/net/ethernet/intel/ice/ice_vf_lib_private.h
index 0c7e77c0a09f..5392b0404986 100644
--- a/drivers/net/ethernet/intel/ice/ice_vf_lib_private.h
+++ b/drivers/net/ethernet/intel/ice/ice_vf_lib_private.h
@@ -24,6 +24,7 @@
 #endif
 
 void ice_initialize_vf_entry(struct ice_vf *vf);
+void ice_deinitialize_vf_entry(struct ice_vf *vf);
 void ice_dis_vf_qs(struct ice_vf *vf);
 int ice_check_vf_init(struct ice_vf *vf);
 enum virtchnl_status_code ice_err_to_virt_err(int err);
-- 
2.45.0