Staging: batman-adv: check all kmalloc()s

there are some kmallocs left which are not checked whether they succeeds or
not, which might lead to corrupted data structures if the system memory is
full. This patch should clean up the remaining unchecked kmalloc()s.

Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

3 files changed, 53 insertions, 14 deletions

diff --git a/drivers/staging/batman-adv/originator.c b/drivers/staging/batman-adv/originator.c
index 6a1fdf2..71bd2cf 100644
--- a/drivers/staging/batman-adv/originator.c
+++ b/drivers/staging/batman-adv/originator.c
@@ -77,6 +77,9 @@ create_neighbor(struct orig_node *orig_node, struct orig_node *orig_neigh_node,
 	bat_dbg(DBG_BATMAN, "Creating new last-hop neighbor of originator\n");
 
 	neigh_node = kmalloc(sizeof(struct neigh_node), GFP_ATOMIC);
+	if (!neigh_node)
+		return NULL;
+
 	memset(neigh_node, 0, sizeof(struct neigh_node));
 	INIT_LIST_HEAD(&neigh_node->list);
 
@@ -127,6 +130,9 @@ struct orig_node *get_orig_node(uint8_t *addr)
 	bat_dbg(DBG_BATMAN, "Creating new originator: %s \n", orig_str);
 
 	orig_node = kmalloc(sizeof(struct orig_node), GFP_ATOMIC);
+	if (!orig_node)
+		return NULL;
+
 	memset(orig_node, 0, sizeof(struct orig_node));
 	INIT_LIST_HEAD(&orig_node->neigh_list);
 
@@ -138,13 +144,20 @@ struct orig_node *get_orig_node(uint8_t *addr)
 	size = num_ifs * sizeof(TYPE_OF_WORD) * NUM_WORDS;
 
 	orig_node->bcast_own = kmalloc(size, GFP_ATOMIC);
+	if (!orig_node->bcast_own)
+		goto free_orig_node;
+
 	memset(orig_node->bcast_own, 0, size);
 
 	size = num_ifs * sizeof(uint8_t);
 	orig_node->bcast_own_sum = kmalloc(size, GFP_ATOMIC);
+	if (!orig_node->bcast_own_sum)
+		goto free_bcast_own;
+
 	memset(orig_node->bcast_own_sum, 0, size);
 
-	hash_add(orig_hash, orig_node);
+	if (hash_add(orig_hash, orig_node) < 0)
+		goto free_bcast_own_sum;
 
 	if (orig_hash->elements * 4 > orig_hash->size) {
 		swaphash = hash_resize(orig_hash, orig_hash->size * 2);
@@ -157,6 +170,13 @@ struct orig_node *get_orig_node(uint8_t *addr)
 	}
 
 	return orig_node;
+free_bcast_own_sum:
+	kfree(orig_node->bcast_own_sum);
+free_bcast_own:
+	kfree(orig_node->bcast_own);
+free_orig_node:
+	kfree(orig_node);
+	return NULL;
 }
 
 static bool purge_orig_neighbors(struct orig_node *orig_node,
diff --git a/drivers/staging/batman-adv/routing.c b/drivers/staging/batman-adv/routing.c
index 37c5382..f8464ca 100644
--- a/drivers/staging/batman-adv/routing.c
+++ b/drivers/staging/batman-adv/routing.c
@@ -154,11 +154,14 @@ static int isBidirectionalNeigh(struct orig_node *orig_node,
 				neigh_node = tmp_neigh_node;
 		}
 
-		if (neigh_node == NULL)
+		if (!neigh_node)
 			neigh_node = create_neighbor(orig_node,
 						     orig_neigh_node,
 						     orig_neigh_node->orig,
 						     if_incoming);
+		/* create_neighbor failed, return 0 */
+		if (!neigh_node)
+			return 0;
 
 		neigh_node->last_valid = jiffies;
 	} else {
@@ -172,11 +175,14 @@ static int isBidirectionalNeigh(struct orig_node *orig_node,
 				neigh_node = tmp_neigh_node;
 		}
 
-		if (neigh_node == NULL)
+		if (!neigh_node)
 			neigh_node = create_neighbor(orig_neigh_node,
 						     orig_neigh_node,
 						     orig_neigh_node->orig,
 						     if_incoming);
+		/* create_neighbor failed, return 0 */
+		if (!neigh_node)
+			return 0;
 	}
 
 	orig_node->last_valid = jiffies;
@@ -260,11 +266,19 @@ static void update_orig(struct orig_node *orig_node, struct ethhdr *ethhdr,
 			ring_buffer_avg(tmp_neigh_node->tq_recv);
 	}
 
-	if (neigh_node == NULL)
+	if (!neigh_node) {
+		struct orig_node *orig_tmp;
+
+		orig_tmp = get_orig_node(ethhdr->h_source);
+		if (!orig_tmp)
+			return;
+
 		neigh_node = create_neighbor(orig_node,
-					     get_orig_node(ethhdr->h_source),
+					     orig_tmp,
 					     ethhdr->h_source, if_incoming);
-	else
+		if (!neigh_node)
+			return;
+	} else
 		bat_dbg(DBG_BATMAN,
 			"Updating existing last-hop neighbor of originator\n");
 
@@ -444,6 +458,9 @@ void receive_bat_packet(struct ethhdr *ethhdr,
 
 		orig_neigh_node = get_orig_node(ethhdr->h_source);
 
+		if (!orig_neigh_node)
+			return;
+
 		/* neighbor has to indicate direct link and it has to
 		 * come via the corresponding interface */
 		/* if received seqno equals last send seqno save new
diff --git a/drivers/staging/batman-adv/translation-table.c b/drivers/staging/batman-adv/translation-table.c
index 088715b..8c8136b 100644
--- a/drivers/staging/batman-adv/translation-table.c
+++ b/drivers/staging/batman-adv/translation-table.c
@@ -317,14 +317,16 @@ void hna_global_add_orig(struct orig_node *orig_node,
 		hna_buff_count++;
 	}
 
-	orig_node->hna_buff_len = hna_buff_len;
-
-	if (orig_node->hna_buff_len > 0) {
-		orig_node->hna_buff = kmalloc(orig_node->hna_buff_len,
-					      GFP_ATOMIC);
-		memcpy(orig_node->hna_buff, hna_buff, orig_node->hna_buff_len);
-	} else {
-		orig_node->hna_buff = NULL;
+	/* initialize, and overwrite if malloc succeeds */
+	orig_node->hna_buff = NULL;
+	orig_node->hna_buff_len = 0;
+
+	if (hna_buff_len > 0) {
+		orig_node->hna_buff = kmalloc(hna_buff_len, GFP_ATOMIC);
+		if (orig_node->hna_buff) {
+			memcpy(orig_node->hna_buff, hna_buff, hna_buff_len);
+			orig_node->hna_buff_len = hna_buff_len;
+		}
 	}
 
 	spin_lock_irqsave(&hna_global_hash_lock, flags);