From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755455Ab3IKE6A (ORCPT ); Wed, 11 Sep 2013 00:58:00 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:3257 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754166Ab3IKE4w (ORCPT ); Wed, 11 Sep 2013 00:56:52 -0400 X-Authority-Analysis: v=2.0 cv=V4T/IJbi c=1 sm=0 a=Sro2XwOs0tJUSHxCKfOySw==:17 a=Drc5e87SC40A:10 a=Ciwy3NGCPMMA:10 a=1EkJrXYOyqQA:10 a=5SG0PmZfjMsA:10 a=bbbx4UPp9XUA:10 a=meVymXHHAAAA:8 a=KGjhK52YXX0A:10 a=ys2x8bRpFFAA:10 a=20KFwNOVAAAA:8 a=VwQbUJbxAAAA:8 a=pGLkceISAAAA:8 a=QyXUC8HyAAAA:8 a=FSAokOOsd0ypDeaCx5wA:9 a=jEp0ucaQiEUA:10 a=MSl-tDqOz04A:10 a=dGJ0OcVc7YAA:10 a=jeBq3FmKZ4MA:10 a=Sro2XwOs0tJUSHxCKfOySw==:117 X-Cloudmark-Score: 0 X-Authenticated-User: X-Originating-IP: 67.255.60.225 Message-Id: <20130911042930.687806996@goodmis.org> User-Agent: quilt/0.60-1 Date: Wed, 11 Sep 2013 00:30:58 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Lukasz Jagiello , Stanislaw Gruszka , Emmanuel Grumbach , Johannes Berg Subject: [231/251] iwlwifi: dvm: fix calling ieee80211_chswitch_done() with NULL References: <20130911042707.738353451@goodmis.org> Content-Disposition: inline; filename=0231-iwlwifi-dvm-fix-calling-ieee80211_chswitch_done-with.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.6.11.9-rc1 stable review patch. If anyone has any objections, please let me know. ------------------ From: Stanislaw Gruszka [ Upstream commit 9186a1fd9ed190739423db84bc344d258ef3e3d7 ] If channel switch is pending and we remove interface we can crash like showed below due to passing NULL vif to mac80211: BUG: unable to handle kernel paging request at fffffffffffff8cc IP: [] strnlen+0xd/0x40 Call Trace: [] string.isra.3+0x3e/0xd0 [] vsnprintf+0x219/0x640 [] vscnprintf+0x11/0x30 [] vprintk_emit+0x115/0x4f0 [] printk+0x61/0x63 [] ieee80211_chswitch_done+0xaf/0xd0 [mac80211] [] iwl_chswitch_done+0x34/0x40 [iwldvm] [] iwlagn_commit_rxon+0x2a3/0xdc0 [iwldvm] [] ? iwlagn_set_rxon_chain+0x180/0x2c0 [iwldvm] [] iwl_set_mode+0x36/0x40 [iwldvm] [] iwlagn_mac_remove_interface+0x8d/0x1b0 [iwldvm] [] ieee80211_do_stop+0x29d/0x7f0 [mac80211] This is because we nulify ctx->vif in iwlagn_mac_remove_interface() before calling some other functions that teardown interface. To fix just check ctx->vif on iwl_chswitch_done(). We should not call ieee80211_chswitch_done() as channel switch works were already canceled by mac80211 in ieee80211_do_stop() -> ieee80211_mgd_stop(). Resolve: https://bugzilla.redhat.com/show_bug.cgi?id=979581 Cc: stable@vger.kernel.org Reported-by: Lukasz Jagiello Signed-off-by: Stanislaw Gruszka Reviewed-by: Emmanuel Grumbach Signed-off-by: Johannes Berg Signed-off-by: Steven Rostedt --- drivers/net/wireless/iwlwifi/dvm/mac80211.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/iwlwifi/dvm/mac80211.c b/drivers/net/wireless/iwlwifi/dvm/mac80211.c index 7a2cf52..515376d 100644 --- a/drivers/net/wireless/iwlwifi/dvm/mac80211.c +++ b/drivers/net/wireless/iwlwifi/dvm/mac80211.c @@ -941,7 +941,10 @@ void iwl_chswitch_done(struct iwl_priv *priv, bool is_success) if (test_bit(STATUS_EXIT_PENDING, &priv->status)) return; - if (test_and_clear_bit(STATUS_CHANNEL_SWITCH_PENDING, &priv->status)) + if (!test_and_clear_bit(STATUS_CHANNEL_SWITCH_PENDING, &priv->status)) + return; + + if (ctx->vif) ieee80211_chswitch_done(ctx->vif, is_success); } -- 1.7.10.4