ice: Fix memory management in ice_ethtool_fdir.c

Fix ethtool FDIR logic to not use memory after its release.
In the ice_ethtool_fdir.c file there are 2 spots where code can
refer to pointers which may be missing.

In the ice_cfg_fdir_xtrct_seq() function seg may be freed but
even then may be still used by memcpy(&tun_seg[1], seg, sizeof(*seg)).

In the ice_add_fdir_ethtool() function struct ice_fdir_fltr *input
may first fail to be added via ice_fdir_update_list_entry() but then
may be deleted by ice_fdir_update_list_entry.

Terminate in both cases when the returned value of the previous
operation is other than 0, free memory and don't use it anymore.

Reported-by: Michal Schmidt <mschmidt@redhat.com>
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2208423
Fixes: cac2a27cd9ab ("ice: Support IPv4 Flow Director filters")
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Signed-off-by: Jedrzej Jagielski <jedrzej.jagielski@intel.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Link: https://lore.kernel.org/r/20230721155854.1292805-1-anthony.l.nguyen@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/intel/ice/ice_ethtool_fdir.c b/drivers/net/ethernet/intel/ice/ice_ethtool_fdir.c
index ead6d50..8c6e13f 100644 (file)
--- a/drivers/net/ethernet/intel/ice/ice_ethtool_fdir.c
+++ b/drivers/net/ethernet/intel/ice/ice_ethtool_fdir.c
@@ -1281,16 +1281,21 @@ ice_cfg_fdir_xtrct_seq(struct ice_pf *pf, struct ethtool_rx_flow_spec *fsp,
                                     ICE_FLOW_FLD_OFF_INVAL);
        }
 
-       /* add filter for outer headers */
        fltr_idx = ice_ethtool_flow_to_fltr(fsp->flow_type & ~FLOW_EXT);
+
+       assign_bit(fltr_idx, hw->fdir_perfect_fltr, perfect_filter);
+
+       /* add filter for outer headers */
        ret = ice_fdir_set_hw_fltr_rule(pf, seg, fltr_idx,
                                        ICE_FD_HW_SEG_NON_TUN);
-       if (ret == -EEXIST)
-               /* Rule already exists, free memory and continue */
-               devm_kfree(dev, seg);
-       else if (ret)
+       if (ret == -EEXIST) {
+               /* Rule already exists, free memory and count as success */
+               ret = 0;
+               goto err_exit;
+       } else if (ret) {
                /* could not write filter, free memory */
                goto err_exit;
+       }
 
        /* make tunneled filter HW entries if possible */
        memcpy(&tun_seg[1], seg, sizeof(*seg));
@@ -1305,18 +1310,13 @@ ice_cfg_fdir_xtrct_seq(struct ice_pf *pf, struct ethtool_rx_flow_spec *fsp,
                devm_kfree(dev, tun_seg);
        }
 
-       if (perfect_filter)
-               set_bit(fltr_idx, hw->fdir_perfect_fltr);
-       else
-               clear_bit(fltr_idx, hw->fdir_perfect_fltr);
-
        return ret;
 
 err_exit:
        devm_kfree(dev, tun_seg);
        devm_kfree(dev, seg);
 
-       return -EOPNOTSUPP;
+       return ret;
 }
 
 /**
@@ -1914,7 +1914,9 @@ int ice_add_fdir_ethtool(struct ice_vsi *vsi, struct ethtool_rxnfc *cmd)
        input->comp_report = ICE_FXD_FLTR_QW0_COMP_REPORT_SW_FAIL;
 
        /* input struct is added to the HW filter list */
-       ice_fdir_update_list_entry(pf, input, fsp->location);
+       ret = ice_fdir_update_list_entry(pf, input, fsp->location);
+       if (ret)
+               goto release_lock;
 
        ret = ice_fdir_write_all_fltr(pf, input, true);
        if (ret)