tipc: Fix sk_buff leaks when link congestion is detected

Modifies a TIPC send routine that did not discard the outgoing sk_buff
if it was not transmitted because of link congestion; this eliminates
the potential for buffer leakage in the many callers who did not clean up
the unsent buffer. (The two routines that previously did discard the unsent
buffer have been updated to eliminate their now-redundant clean up.)

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

diff --git a/net/tipc/bcast.c b/net/tipc/bcast.c
index 08e3216a33d29d67532db20031499fbcb633e937..fa68d1e9ff4bd370e6db2b086aeb9a37b1651926 100644 (file)
--- a/net/tipc/bcast.c
+++ b/net/tipc/bcast.c
@@ -407,9 +407,7 @@ int tipc_bclink_send_msg(struct sk_buff *buf)
        spin_lock_bh(&bc_lock);
 
        res = tipc_link_send_buf(bcl, buf);
-       if (unlikely(res == -ELINKCONG))
-               buf_discard(buf);
-       else
+       if (likely(res > 0))
                bclink_set_last_sent();
 
        bcl->stats.queue_sz_counts++;

diff --git a/net/tipc/link.c b/net/tipc/link.c
index 02b083e5c2194ab13093cbf8d983a7c57516a61b..2a9f44a203ebf71210ff95cc8c64b23a842cc7da 100644 (file)
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -864,8 +864,9 @@ int tipc_link_send_buf(struct link *l_ptr, struct sk_buff *buf)
 
        if (unlikely(queue_size >= queue_limit)) {
                if (imp <= TIPC_CRITICAL_IMPORTANCE) {
-                       return link_schedule_port(l_ptr, msg_origport(msg),
-                                                 size);
+                       link_schedule_port(l_ptr, msg_origport(msg), size);
+                       buf_discard(buf);
+                       return -ELINKCONG;
                }
                buf_discard(buf);
                if (imp > CONN_MANAGER) {
@@ -1069,8 +1070,6 @@ again:
                        if (likely(buf)) {
                                res = link_send_buf_fast(l_ptr, buf,
                                                         &sender->max_pkt);
-                               if (unlikely(res < 0))
-                                       buf_discard(buf);
 exit:
                                tipc_node_unlock(node);
                                read_unlock_bh(&tipc_net_lock);