From: Ping-Ke Shih pkshih@realtek.com
[ Upstream commit 5174f1e41074b5186608badc2e89441d021e8c08 ]
This leak was found by testing 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 is because 8192cu doesn't implement usb_cmd_send_packet(), and this patch just frees the skb within the function to resolve memleak problem by now. Since 8192cu doesn't turn on fwctrl_lps that needs to download command packet for firmware via the function, applying this patch doesn't affect driver behavior.
Reported-by: Stefan Wahren wahrenst@gmx.net Signed-off-by: Ping-Ke Shih pkshih@realtek.com Signed-off-by: Kalle Valo kvalo@codeaurora.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/wireless/realtek/rtlwifi/rtl8192cu/hw.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/net/wireless/realtek/rtlwifi/rtl8192cu/hw.c b/drivers/net/wireless/realtek/rtlwifi/rtl8192cu/hw.c index 34ce06441d1b6..137d7c8645dae 100644 --- a/drivers/net/wireless/realtek/rtlwifi/rtl8192cu/hw.c +++ b/drivers/net/wireless/realtek/rtlwifi/rtl8192cu/hw.c @@ -1601,6 +1601,8 @@ 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; }