diff options
| author | Stanislaw Gruszka <sgruszka@redhat.com> | 2013-07-26 15:29:09 +0200 |
|---|---|---|
| committer | Johannes Berg <johannes.berg@intel.com> | 2013-07-31 08:54:25 +0200 |
| commit | 9186a1fd9ed190739423db84bc344d258ef3e3d7 (patch) | |
| tree | 8eabaa9dfd2eaa35f09592ae6fa30785ca533011 /drivers/net/wireless/iwlwifi/dvm/mac80211.c | |
| parent | a53ee0a308b16e392e0219c585b10f329345766b (diff) | |
iwlwifi: dvm: fix calling ieee80211_chswitch_done() with NULL
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
Cc: stable@vger.kernel.org
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>
Diffstat (limited to 'drivers/net/wireless/iwlwifi/dvm/mac80211.c')
| -rw-r--r-- | drivers/net/wireless/iwlwifi/dvm/mac80211.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/net/wireless/iwlwifi/dvm/mac80211.c b/drivers/net/wireless/iwlwifi/dvm/mac80211.c index 822f1a00efb..319387263e1 100644 --- a/drivers/net/wireless/iwlwifi/dvm/mac80211.c +++ b/drivers/net/wireless/iwlwifi/dvm/mac80211.c @@ -1068,7 +1068,10 @@ 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); } |