From: Johannes Berg <johannes.berg@intel.com>
Date: Wed, 8 May 2013 13:55:31 +0000 (+0200)
Subject: iwlwifi: mvm: sanity check context in iwl_mvm_phy_ctxt_unref()
X-Git-Tag: next-20130607~64^2~32^2~23
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=e28210115b0ff3544b39ee67d8e48dc74b25b6b8;p=karo-tx-linux.git

iwlwifi: mvm: sanity check context in iwl_mvm_phy_ctxt_unref()

In some botched (!) restart scenarios we seem to get here with
a NULL PHY context, so warn and exit instead of crashing.

Reported-by: Omer Kremer <omerx.kremer@intel.com>
Reviewed-by: Ilan Peer <ilan.peer@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---

diff --git a/drivers/net/wireless/iwlwifi/mvm/phy-ctxt.c b/drivers/net/wireless/iwlwifi/mvm/phy-ctxt.c
index 0ea61aaf7754..1b4db25d53fb 100644
--- a/drivers/net/wireless/iwlwifi/mvm/phy-ctxt.c
+++ b/drivers/net/wireless/iwlwifi/mvm/phy-ctxt.c
@@ -245,5 +245,9 @@ int iwl_mvm_phy_ctxt_changed(struct iwl_mvm *mvm, struct iwl_mvm_phy_ctxt *ctxt,
 void iwl_mvm_phy_ctxt_unref(struct iwl_mvm *mvm, struct iwl_mvm_phy_ctxt *ctxt)
 {
 	lockdep_assert_held(&mvm->mutex);
+
+	if (WARN_ON_ONCE(!ctxt))
+		return;
+
 	ctxt->ref--;
 }