diff options
| author | Stanislaw Gruszka <sgruszka@redhat.com> | 2014-02-27 09:53:01 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-03-11 16:10:10 -0700 |
| commit | 60e691100e48fea19bf35b28aa886ec12c892bab (patch) | |
| tree | 9d469f75f29181e4e9f426937d730ffcff88ed17 | |
| parent | b38b29d58fe03950b2ccd5eaa9af2acb3c1f084d (diff) | |
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>
[bwh: Backported to 3.2: adjust context, filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
[wujg: Backported to 3.4: - adjust context]
Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/net/wireless/iwlwifi/iwl-core.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/net/wireless/iwlwifi/iwl-core.c b/drivers/net/wireless/iwlwifi/iwl-core.c index 46490d3b95b9..75ebb829c327 100644 --- a/drivers/net/wireless/iwlwifi/iwl-core.c +++ b/drivers/net/wireless/iwlwifi/iwl-core.c @@ -801,7 +801,10 @@ 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); } |