Refactor tipc_node_xmit() to fail fast and fail early. Fix several
potential memory leaks in unexpected error paths.
Reported-by: Dmitry Vyukov <dvyu...@google.com>
Reviewed-by: Jon Maloy <jon.ma...@ericsson.com>
Signed-off-by: Richard Alpe <richard.a...@ericsson.com>
---
net/tipc/link.c | 8 ++++++--
net/tipc/node.c | 54 ++++++++++++++++++++++++++++++++----------------------
2 files changed, 38 insertions(+), 24 deletions(-)
diff --git a/net/tipc/link.c b/net/tipc/link.c
index 6f4a6d9..3e513da 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -903,8 +903,10 @@ int tipc_link_xmit(struct tipc_link *l, struct
sk_buff_head *list,
if (unlikely(l->backlog[i].len >= l->backlog[i].limit))
return link_schedule_user(l, list);
}
- if (unlikely(msg_size(hdr) > mtu))
+ if (unlikely(msg_size(hdr) > mtu)) {
+ skb_queue_purge(list);
return -EMSGSIZE;
+ }
/* Prepare each packet for sending, and add to relevant queue: */
while (skb_queue_len(list)) {
@@ -916,8 +918,10 @@ int tipc_link_xmit(struct tipc_link *l, struct
sk_buff_head *list,
if (likely(skb_queue_len(transmq) < maxwin)) {
_skb = skb_clone(skb, GFP_ATOMIC);
- if (!_skb)
+ if (!_skb) {
+ skb_queue_purge(list);
return -ENOBUFS;
+ }
__skb_dequeue(list);
__skb_queue_tail(transmq, skb);
__skb_queue_tail(xmitq, _skb);
diff --git a/net/tipc/node.c b/net/tipc/node.c
index f8a8255..10a1e87 100644
--- a/net/tipc/node.c
+++ b/net/tipc/node.c
@@ -1166,7 +1166,7 @@ msg_full:
* @dnode: address of destination node
* @selector: a number used for deterministic link selection
* Consumes the buffer chain, except when returning -ELINKCONG
- * Returns 0 if success, otherwise errno: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE
+ * Returns 0 if success, otherwise: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE,-ENOBUF
*/
int tipc_node_xmit(struct net *net, struct sk_buff_head *list,
u32 dnode, int selector)
@@ -1174,33 +1174,43 @@ int tipc_node_xmit(struct net *net, struct sk_buff_head
*list,
struct tipc_link_entry *le = NULL;
struct tipc_node *n;
struct sk_buff_head xmitq;
- int bearer_id = -1;
- int rc = -EHOSTUNREACH;
+ int bearer_id;
+ int rc;
+
+ if (in_own_node(net, dnode)) {
+ tipc_sk_rcv(net, list);
+ return 0;
+ }
- __skb_queue_head_init(&xmitq);
n = tipc_node_find(net, dnode);
- if (likely(n)) {
- tipc_node_read_lock(n);
- bearer_id = n->active_links[selector & 1];
- if (bearer_id >= 0) {
- le = &n->links[bearer_id];
- spin_lock_bh(&le->lock);
- rc = tipc_link_xmit(le->link, list, &xmitq);
- spin_unlock_bh(&le->lock);
- }
+ if (unlikely(!n)) {
+ skb_queue_purge(list);
+ return -EHOSTUNREACH;
+ }
+
+ tipc_node_read_lock(n);
+ bearer_id = n->active_links[selector & 1];
+ if (unlikely(bearer_id == INVALID_BEARER_ID)) {
tipc_node_read_unlock(n);
- if (likely(!rc))
- tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr);
- else if (rc == -ENOBUFS)
- tipc_node_link_down(n, bearer_id, false);
tipc_node_put(n);
- return rc;
+ skb_queue_purge(list);
+ return -EHOSTUNREACH;
}
- if (likely(in_own_node(net, dnode))) {
- tipc_sk_rcv(net, list);
- return 0;
- }
+ __skb_queue_head_init(&xmitq);
+ le = &n->links[bearer_id];
+ spin_lock_bh(&le->lock);
+ rc = tipc_link_xmit(le->link, list, &xmitq);
+ spin_unlock_bh(&le->lock);
+ tipc_node_read_unlock(n);
+
+ if (likely(rc == 0))
+ tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr);
+ else if (rc == -ENOBUFS)
+ tipc_node_link_down(n, bearer_id, false);
+
+ tipc_node_put(n);
+
return rc;
}
--
2.1.4
