From: Bing Zhao Date: Wed, 25 Sep 2013 02:31:25 +0000 (-0700) Subject: mwifiex: fix NULL pointer dereference in usb suspend handler X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=346ece0b7ba2730b4d633b9e371fe55488803102;p=sagit-ice-cold%2Fkernel_xiaomi_msm8998.git mwifiex: fix NULL pointer dereference in usb suspend handler Bug 60815 - Interface hangs in mwifiex_usb https://bugzilla.kernel.org/show_bug.cgi?id=60815 [ 2.883807] BUG: unable to handle kernel NULL pointer dereference at 0000000000000048 [ 2.883813] IP: [] pfifo_fast_enqueue+0x90/0x90 [ 2.883834] CPU: 1 PID: 3220 Comm: kworker/u8:90 Not tainted 3.11.1-monotone-l0 #6 [ 2.883834] Hardware name: Microsoft Corporation Surface with Windows 8 Pro/Surface with Windows 8 Pro, BIOS 1.03.0450 03/29/2013 On Surface Pro, suspend to ram gives a NULL pointer dereference in pfifo_fast_enqueue(). The stack trace reveals that the offending call is clearing carrier in mwifiex_usb suspend handler. Since commit 1499d9f "mwifiex: don't drop carrier flag over suspend" has removed the carrier flag handling over suspend/resume in SDIO and PCIe drivers, I'm removing it in USB driver too. This also fixes the bug for Surface Pro. Cc: # 3.5+ Tested-by: Dmitry Khromov Signed-off-by: Bing Zhao Signed-off-by: John W. Linville --- diff --git a/drivers/net/wireless/mwifiex/usb.c b/drivers/net/wireless/mwifiex/usb.c index 2472d4b7f00e..1c70b8d09227 100644 --- a/drivers/net/wireless/mwifiex/usb.c +++ b/drivers/net/wireless/mwifiex/usb.c @@ -447,9 +447,6 @@ static int mwifiex_usb_suspend(struct usb_interface *intf, pm_message_t message) */ adapter->is_suspended = true; - for (i = 0; i < adapter->priv_num; i++) - netif_carrier_off(adapter->priv[i]->netdev); - if (atomic_read(&card->rx_cmd_urb_pending) && card->rx_cmd.urb) usb_kill_urb(card->rx_cmd.urb); @@ -509,10 +506,6 @@ static int mwifiex_usb_resume(struct usb_interface *intf) MWIFIEX_RX_CMD_BUF_SIZE); } - for (i = 0; i < adapter->priv_num; i++) - if (adapter->priv[i]->media_connected) - netif_carrier_on(adapter->priv[i]->netdev); - /* Disable Host Sleep */ if (adapter->hs_activated) mwifiex_cancel_hs(mwifiex_get_priv(adapter,