tipc: refactor node xmit and fix memory leaks

Refactor tipc_node_xmit() to fail fast and fail early. Fix several
potential memory leaks in unexpected error paths.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Richard Alpe <richard.alpe@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Richard Alpe 2016-02-11 10:43:15 +01:00 committed by David S. Miller
parent 37ace20a3c
commit 4952cd3e7b
2 changed files with 40 additions and 26 deletions

View File

@ -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);

View File

@ -1166,7 +1166,7 @@ static int __tipc_nl_add_node(struct tipc_nl_msg *msg, struct tipc_node *node)
* @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;
__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);
}
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;
}
if (likely(in_own_node(net, dnode))) {
if (in_own_node(net, dnode)) {
tipc_sk_rcv(net, list);
return 0;
}
n = tipc_node_find(net, dnode);
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);
tipc_node_put(n);
skb_queue_purge(list);
return -EHOSTUNREACH;
}
__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;
}