5.0-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit f9264dd687f8d3f9104c9900f8f3e5e419f27c55 ]
When adding multiple VLANs to the same VSI, the ice_add_vlan code will share the VSI list, so as not to create multiple unnecessary VSI lists.
Consider the following flow
ice_add_vlan(hw, <VSI 0 VID 7, VSI 0 VID 8, VSI 0 VID 9>)
Where we add three VLAN filters for VIDs 7, 8, and 9, all for VSI 0.
The ice_add_vlan will create a single vsi_list and share it among all the filters.
Later, if we try to remove a VLAN,
ice_remove_vlan(hw, <VSI 0 VID 7>)
Then the removal code will update the vsi_list and remove VSI 0 from it. But, since the vsi_list is shared, this breaks the list for the other users who reference it. We actually even free the VSI list memory, and may result in segmentation faults.
This is due to the way that VLAN rule share VSI lists with reference counts, and is caused because we call ice_rem_update_vsi_list even when the ref_cnt is greater than one.
To fix this, handle the case where ref_cnt is greater than one separately. In this case, we need to remove the associated rule without modifying the vsi_list, since it is currently being referenced by another rule. Instead, we just need to decrement the VSI list ref_cnt.
The case for handling sharing of VSI lists with multiple VSIs is not currently supported by this code. No such rules will be created today, and this code will require changes if/when such code is added.
Signed-off-by: Jacob Keller jacob.e.keller@intel.com Reviewed-by: Bruce Allan bruce.w.allan@intel.com Signed-off-by: Anirudh Venkataramanan anirudh.venkataramanan@intel.com Tested-by: Andrew Bowers andrewx.bowers@intel.com Signed-off-by: Jeff Kirsher jeffrey.t.kirsher@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/intel/ice/ice_switch.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/intel/ice/ice_switch.c b/drivers/net/ethernet/intel/ice/ice_switch.c index 2e5693107fa4..8d602247eb44 100644 --- a/drivers/net/ethernet/intel/ice/ice_switch.c +++ b/drivers/net/ethernet/intel/ice/ice_switch.c @@ -1538,9 +1538,20 @@ ice_remove_rule_internal(struct ice_hw *hw, u8 recp_id, } else if (!list_elem->vsi_list_info) { status = ICE_ERR_DOES_NOT_EXIST; goto exit; + } else if (list_elem->vsi_list_info->ref_cnt > 1) { + /* a ref_cnt > 1 indicates that the vsi_list is being + * shared by multiple rules. Decrement the ref_cnt and + * remove this rule, but do not modify the list, as it + * is in-use by other rules. + */ + list_elem->vsi_list_info->ref_cnt--; + remove_rule = true; } else { - if (list_elem->vsi_list_info->ref_cnt > 1) - list_elem->vsi_list_info->ref_cnt--; + /* a ref_cnt of 1 indicates the vsi_list is only used + * by one rule. However, the original removal request is only + * for a single VSI. Update the vsi_list first, and only + * remove the rule if there are no further VSIs in this list. + */ vsi_handle = f_entry->fltr_info.vsi_handle; status = ice_rem_update_vsi_list(hw, vsi_handle, list_elem); if (status)