| Message ID | 1377820038-27920-1-git-send-email-kamal@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/drivers/net/wireless/iwlwifi/dvm/mac80211.c b/drivers/net/wireless/iwlwifi/dvm/mac80211.c index c784f69..70c32db 100644 --- a/drivers/net/wireless/iwlwifi/dvm/mac80211.c +++ b/drivers/net/wireless/iwlwifi/dvm/mac80211.c @@ -961,7 +961,10 @@ 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); }
This is a note to let you know that I have just added a patch titled iwlwifi: dvm: fix calling ieee80211_chswitch_done() with NULL to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue This patch is scheduled to be released in version 3.8.13.8. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.8.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From afb7963fd5895a45d84cadb978d3696cb1c772e5 Mon Sep 17 00:00:00 2001 From: Stanislaw Gruszka <sgruszka@redhat.com> Date: Fri, 26 Jul 2013 15:29:09 +0200 Subject: iwlwifi: dvm: fix calling ieee80211_chswitch_done() with NULL commit 9186a1fd9ed190739423db84bc344d258ef3e3d7 upstream. 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: [<ffffffff8130924d>] strnlen+0xd/0x40 Call Trace: [<ffffffff8130ad2e>] string.isra.3+0x3e/0xd0 [<ffffffff8130bf99>] vsnprintf+0x219/0x640 [<ffffffff8130c481>] vscnprintf+0x11/0x30 [<ffffffff81061585>] vprintk_emit+0x115/0x4f0 [<ffffffff81657bd5>] printk+0x61/0x63 [<ffffffffa048987f>] ieee80211_chswitch_done+0xaf/0xd0 [mac80211] [<ffffffffa04e7b34>] iwl_chswitch_done+0x34/0x40 [iwldvm] [<ffffffffa04f83c3>] iwlagn_commit_rxon+0x2a3/0xdc0 [iwldvm] [<ffffffffa04ebc50>] ? iwlagn_set_rxon_chain+0x180/0x2c0 [iwldvm] [<ffffffffa04e5e76>] iwl_set_mode+0x36/0x40 [iwldvm] [<ffffffffa04e5f0d>] iwlagn_mac_remove_interface+0x8d/0x1b0 [iwldvm] [<ffffffffa0459b3d>] 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 Reported-by: Lukasz Jagiello <jagiello.lukasz@gmail.com> Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/net/wireless/iwlwifi/dvm/mac80211.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) -- 1.8.1.2