> -----Original Message----- > From: Stefan Wahren [mailto:wahrenst@xxxxxxx] > Sent: Thursday, October 31, 2019 9:57 PM > To: Pkshih; Larry Finger > Cc: colin.king@xxxxxxxxxxxxx; kvalo@xxxxxxxxxxxxxx; linux-wireless@xxxxxxxxxxxxxxx; > netdev@xxxxxxxxxxxxxxx > Subject: rtlwifi: Memory leak in rtl92c_set_fw_rsvdpagepkt() > > Hi, > > i tested the EDIMAX EW-7612 on Raspberry Pi 3B+ with Linux 5.4-rc5 > (multi_v7_defconfig + rtlwifi + kmemleak) and noticed a single memory > leak during probe: > > unreferenced object 0xec13ee40 (size 176): > comm "kworker/u8:1", pid 36, jiffies 4294939321 (age 5580.790s) > hex dump (first 32 bytes): > 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > backtrace: > [<fc1bbb3e>] __netdev_alloc_skb+0x9c/0x164 > [<863dfa6e>] rtl92c_set_fw_rsvdpagepkt+0x254/0x340 [rtl8192c_common] > [<9572be0d>] rtl92cu_set_hw_reg+0xf48/0xfa4 [rtl8192cu] > [<116df4d8>] rtl_op_bss_info_changed+0x234/0x96c [rtlwifi] > [<8933575f>] ieee80211_bss_info_change_notify+0xb8/0x264 [mac80211] > [<d4061e86>] ieee80211_assoc_success+0x934/0x1798 [mac80211] > [<e55adb56>] ieee80211_rx_mgmt_assoc_resp+0x174/0x314 [mac80211] > [<5974629e>] ieee80211_sta_rx_queued_mgmt+0x3f4/0x7f0 [mac80211] > [<d91091c6>] ieee80211_iface_work+0x208/0x318 [mac80211] > [<ac5fcae4>] process_one_work+0x22c/0x564 > [<f5e6d3b6>] worker_thread+0x44/0x5d8 > [<82c7b073>] kthread+0x150/0x154 > [<b43e1b7d>] ret_from_fork+0x14/0x2c > [<794dff30>] 0x0 > > It looks like the allocated skd is never freed. > > Would be nice to get this fixed. > Hi, This is due to 8192cu doesn't implement usb_cmd_send_packet(). Could you help following patch? diff --git a/drivers/net/wireless/realtek/rtlwifi/rtl8192cu/hw.c b/drivers/net/wireless/realtek/rtlwifi/rtl8192cu/hw.c index 56cc3bc30860..f070f25bb735 100644 --- a/drivers/net/wireless/realtek/rtlwifi/rtl8192cu/hw.c +++ b/drivers/net/wireless/realtek/rtlwifi/rtl8192cu/hw.c @@ -1540,6 +1540,8 @@ static bool usb_cmd_send_packet(struct ieee80211_hw *hw, struct sk_buff *skb) * This is maybe necessary: * rtlpriv->cfg->ops->fill_tx_cmddesc(hw, buffer, 1, 1, skb); */ + dev_kfree_skb(skb); + return true; } This patch just frees the skb to resolve memleak problem. Since 8192cu doesn't turn on fwctrl_lps that needs to download command packet to firmware, apply this patch isn't worse than before. --- PK
