[bug report] rtlwifi: 8192de: Reduce indentation and fix coding style

[bug report] rtlwifi: 8192de: Reduce indentation and fix coding style

[Dan Carpenter]

[ This code is predates your patch which just cleaned up the code. - dan ]

Hello Ping-Ke Shih,

The patch 3bde4ed3da38: "rtlwifi: 8192de: Reduce indentation and fix
coding style" from May 10, 2019, leads to the following static
checker warning:

	drivers/net/wireless/realtek/rtlwifi/rtl8192de/dm.c:999 rtl92d_dm_txpower_tracking_callback_thermalmeter()
	error: buffer overflow 'ofdm_index' 2 <= 2 (assuming for loop doesn't break)

drivers/net/wireless/realtek/rtlwifi/rtl8192de/dm.c
   769  static void rtl92d_dm_txpower_tracking_callback_thermalmeter(
   770                          struct ieee80211_hw *hw)
   771  {
   772          struct rtl_priv *rtlpriv = rtl_priv(hw);
   773          struct rtl_hal *rtlhal = rtl_hal(rtl_priv(hw));
   774          struct rtl_phy *rtlphy = &(rtlpriv->phy);
   775          struct rtl_efuse *rtlefuse = rtl_efuse(rtl_priv(hw));
   776          u8 thermalvalue, delta, delta_lck, delta_iqk, delta_rxgain;
   777          u8 offset, thermalvalue_avg_count = 0;
   778          u32 thermalvalue_avg = 0;
   779          bool internal_pa = false;
   780          long ele_a = 0, ele_d, temp_cck, val_x, value32;
   781          long val_y, ele_c = 0;
   782          u8 ofdm_index[2];
                ^^^^^^^^^^^^^^^^
ofdm_index[] has two elements.

   783          s8 cck_index = 0;
   784          u8 ofdm_index_old[2] = {0, 0};
   785          s8 cck_index_old = 0;
   786          u8 index;
   787          int i;
   788          bool is2t = IS_92D_SINGLEPHY(rtlhal->version);
                ^^^^^^^^^^^
is2t is set here.

   789          u8 ofdm_min_index = 6, ofdm_min_index_internal_pa = 3, rf;
   790          u8 indexforchannel =
   791              rtl92d_get_rightchnlplace_for_iqk(rtlphy->current_channel);
   792          static const u8 index_mapping[5][INDEX_MAPPING_NUM] = {
   793                  /* 5G, path A/MAC 0, decrease power  */
   794                  {0, 1, 3, 6, 8, 9,      11, 13, 14, 16, 17, 18, 18},
   795                  /* 5G, path A/MAC 0, increase power  */

[ snip ]

   830          rtl92d_phy_ap_calibrate(hw, (thermalvalue -
   831                                       rtlefuse->eeprom_thermalmeter));
   832  
   833          if (!thermalvalue)
   834                  goto exit;
   835  
   836          if (is2t)
   837                  rf = 2;
   838          else
   839                  rf = 1;

"rf" is either 1 or 2 depending on "is2t".

   840  
   841          if (rtlpriv->dm.thermalvalue && !rtlhal->reloadtxpowerindex)
   842                  goto old_index_done;
   843  
   844          ele_d = rtl_get_bbreg(hw, ROFDM0_XATXIQIMBALANCE,  MASKDWORD) & MASKOFDM_D;

[ snip ]

   983                  rtl_dbg(rtlpriv, COMP_POWER_TRACKING, DBG_LOUD,
   984                          "temp OFDM_A_index=0x%x,cck_index = 0x%x\n",
   985                          rtlpriv->dm.ofdm_index[0],
   986                          rtlpriv->dm.cck_index);
   987          }
   988          for (i = 0; i < rf; i++) {
   989                  if (ofdm_index[i] > OFDM_TABLE_SIZE_92D - 1)
   990                          ofdm_index[i] = OFDM_TABLE_SIZE_92D - 1;
   991                  else if (ofdm_index[i] < ofdm_min_index)
   992                          ofdm_index[i] = ofdm_min_index;
   993          }

i is equal to "rf" after this loop.

   994          if (rtlhal->current_bandtype == BAND_ON_2_4G) {
   995                  if (cck_index > CCK_TABLE_SIZE - 1) {
   996                          cck_index = CCK_TABLE_SIZE - 1;
   997                  } else if (internal_pa ||
   998                             rtlhal->current_bandtype == BAND_ON_2_4G) {
   999                          if (ofdm_index[i] < ofdm_min_index_internal_pa)
                                    ^^^^^^^^^^^^^
  1000                                  ofdm_index[i] = ofdm_min_index_internal_pa;
                                        ^^^^^^^^^^^^^

Using "i" after we exited the loop without hitting a break looks wrong
to me.  It's potentially correct if we know that "is2t" is false but how
do we know that?

  1001                  } else if (cck_index < 0) {
  1002                          cck_index = 0;
  1003                  }
  1004          }
  1005          if (is2t) {
  1006                  rtl_dbg(rtlpriv, COMP_POWER_TRACKING, DBG_LOUD,
  1007                          "new OFDM_A_index=0x%x, OFDM_B_index = 0x%x, cck_index=0x%x\n",
  1008                          ofdm_index[0], ofdm_index[1],
  1009                          cck_index);

regards,
dan carpenter