2003-06-15 09:14:55

by Oleg Drokin

[permalink] [raw]
Subject: [2.4] memleak in implementation of the IEEE 802.2 LLC protocol?

Hello!

I am trying to teach smatch's unfree script of skbuffers as those could
create memory leaks if not freed, and I come across this code in
./net/802/llc_sendpdu.c::llc_sendipdu() in 2.4.21 kernel:
tmp=skb_clone(skb, GFP_ATOMIC);
if(tmp!=NULL)
{
tmp->dev = lp->dev;
dev_queue_xmit(skb);
}
(and tmp is not used anywhere else)

Naturally looking at llc_sendipdu() function that have similar construction,
I think that this small change should be done to avoid memleak
and to make the code correct, what do you think?

===== net/802/llc_sendpdu.c 1.3 vs edited =====
--- 1.3/net/802/llc_sendpdu.c Tue Feb 5 10:39:14 2002
+++ edited/net/802/llc_sendpdu.c Sun Jun 15 13:23:39 2003
@@ -283,7 +283,7 @@
if(tmp!=NULL)
{
tmp->dev = lp->dev;
- dev_queue_xmit(skb);
+ dev_queue_xmit(tmp);
}
resend_count++;
skb = skb->next;

Bye,
Oleg