Hello! On 3/21/2017 2:47 AM, Jeff Kirsher wrote:
From: Jacob Keller <jacob.e.kel...@intel.com> Refactor the exit flow of the i40e_add_fdir_ethtool function. Move the input_label to the end of the function, removing the dependency on
I don't see 'input_label' anywhere. Perhaps 'free_input' label was meant?
having a non-zero return value. Add a comment explaining why it is ok not to free the fdir data structure, because the structure is now stored in the fdir_filter_list. Change-Id: I723342181d59cd0c9f3b31140c37961ba37bb242 Signed-off-by: Jacob Keller <jacob.e.kel...@intel.com> Tested-by: Andrew Bowers <andrewx.bow...@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirs...@intel.com> --- drivers/net/ethernet/intel/i40e/i40e_ethtool.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c index 7a22b473dbdd..d16a5a6b24fc 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c +++ b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c @@ -2828,12 +2828,19 @@ static int i40e_add_fdir_ethtool(struct i40e_vsi *vsi, } ret = i40e_add_del_fdir(vsi, input, true); -free_input: if (ret) - kfree(input); - else - i40e_update_ethtool_fdir_entry(vsi, input, fsp->location, NULL); + goto free_input; + + /* Add the input filter to the fdir_input_list, possibly replacing + * a previous filter. Do not free the input structure after adding it + * to the list as this would cause a use-after-free bug. + */ + i40e_update_ethtool_fdir_entry(vsi, input, fsp->location, NULL); + return 0; + +free_input: + kfree(input); return ret; }
MBR, Sergei