[PATCH 09/16] Staging: batman-adv: unify orig_hash_lock spinlock handling to avoid deadlocks

[Greg Kroah-Hartman]

From: Marek Lindner <lindner_marek at yahoo.de>

The orig_hash_lock spinlock always has to be locked with IRQs being
disabled to avoid deadlocks between code that is being executed in
IRQ context and code that is being executed in non-IRQ context.

Reported-by: Sven Eckelmann <sven.eckelmann at gmx.de>
Signed-off-by: Marek Lindner <lindner_marek at yahoo.de>
Signed-off-by: Sven Eckelmann <sven.eckelmann at gmx.de>
Cc: stable <stable at kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh at suse.de>
---
 drivers/staging/batman-adv/originator.c |   14 ++++++++------
 1 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/staging/batman-adv/originator.c b/drivers/staging/batman-adv/originator.c
index 28bb627..de5a8c1 100644
--- a/drivers/staging/batman-adv/originator.c
+++ b/drivers/staging/batman-adv/originator.c
@@ -391,11 +391,12 @@ static int orig_node_add_if(struct orig_node *orig_node, int max_if_num)
 int orig_hash_add_if(struct batman_if *batman_if, int max_if_num)
 {
 	struct orig_node *orig_node;
+	unsigned long flags;
 	HASHIT(hashit);
 
 	/* resize all orig nodes because orig_node->bcast_own(_sum) depend on
 	 * if_num */
-	spin_lock(&orig_hash_lock);
+	spin_lock_irqsave(&orig_hash_lock, flags);
 
 	while (hash_iterate(orig_hash, &hashit)) {
 		orig_node = hashit.bucket->data;
@@ -404,11 +405,11 @@ int orig_hash_add_if(struct batman_if *batman_if, int max_if_num)
 			goto err;
 	}
 
-	spin_unlock(&orig_hash_lock);
+	spin_unlock_irqrestore(&orig_hash_lock, flags);
 	return 0;
 
 err:
-	spin_unlock(&orig_hash_lock);
+	spin_unlock_irqrestore(&orig_hash_lock, flags);
 	return -ENOMEM;
 }
 
@@ -468,12 +469,13 @@ int orig_hash_del_if(struct batman_if *batman_if, int max_if_num)
 {
 	struct batman_if *batman_if_tmp;
 	struct orig_node *orig_node;
+	unsigned long flags;
 	HASHIT(hashit);
 	int ret;
 
 	/* resize all orig nodes because orig_node->bcast_own(_sum) depend on
 	 * if_num */
-	spin_lock(&orig_hash_lock);
+	spin_lock_irqsave(&orig_hash_lock, flags);
 
 	while (hash_iterate(orig_hash, &hashit)) {
 		orig_node = hashit.bucket->data;
@@ -500,10 +502,10 @@ int orig_hash_del_if(struct batman_if *batman_if, int max_if_num)
 	rcu_read_unlock();
 
 	batman_if->if_num = -1;
-	spin_unlock(&orig_hash_lock);
+	spin_unlock_irqrestore(&orig_hash_lock, flags);
 	return 0;
 
 err:
-	spin_unlock(&orig_hash_lock);
+	spin_unlock_irqrestore(&orig_hash_lock, flags);
 	return -ENOMEM;
 }
-- 
1.7.2