[tipc-discussion] [PATCH net] tipc: fix a possible memleak in tipc_buf_append

[Xin L. <luc...@gm...>]

__skb_linearize() doesn't free the skb when it fails, so move
'*buf = NULL' after __skb_linearize(), so that the skb can be
freed on the err path.

Fixes: b7df21cf1b79 ("tipc: skb_linearize the head skb when reassembling msgs")
Reported-by: Paolo Abeni <pa...@re...>
Signed-off-by: Xin Long <luc...@gm...>
---
 net/tipc/msg.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/tipc/msg.c b/net/tipc/msg.c
index 5c9fd4791c4b..c52ab423082c 100644
--- a/net/tipc/msg.c
+++ b/net/tipc/msg.c
@@ -142,9 +142,9 @@ int tipc_buf_append(struct sk_buff **headbuf, struct sk_buff **buf)
 	if (fragid == FIRST_FRAGMENT) {
 		if (unlikely(head))
 			goto err;
-		*buf = NULL;
 		if (skb_has_frag_list(frag) && __skb_linearize(frag))
 			goto err;
+		*buf = NULL;
 		frag = skb_unshare(frag, GFP_ATOMIC);
 		if (unlikely(!frag))
 			goto err;
-- 
2.43.0