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| author | Lv Yunlong <lyl2019@mail.ustc.edu.cn> | 2021-03-28 00:30:29 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2021-03-29 16:21:37 -0700 |
| commit | 6bf24dc0cc0cc43b29ba344b66d78590e687e046 (patch) | |
| tree | 2487000b43508a8da3d163c7f5165104749eb246 /net/tipc | |
| parent | 1bfb3dea965ff9f6226fd1709338f227363b6061 (diff) | |
| download | linux-6bf24dc0cc0cc43b29ba344b66d78590e687e046.tar.bz2 | |
net:tipc: Fix a double free in tipc_sk_mcast_rcv
In the if(skb_peek(arrvq) == skb) branch, it calls __skb_dequeue(arrvq) to get
the skb by skb = skb_peek(arrvq). Then __skb_dequeue() unlinks the skb from arrvq
and returns the skb which equals to skb_peek(arrvq). After __skb_dequeue(arrvq)
finished, the skb is freed by kfree_skb(__skb_dequeue(arrvq)) in the first time.
Unfortunately, the same skb is freed in the second time by kfree_skb(skb) after
the branch completed.
My patch removes kfree_skb() in the if(skb_peek(arrvq) == skb) branch, because
this skb will be freed by kfree_skb(skb) finally.
Fixes: cb1b728096f54 ("tipc: eliminate race condition at multicast reception")
Signed-off-by: Lv Yunlong <lyl2019@mail.ustc.edu.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/tipc')
| -rw-r--r-- | net/tipc/socket.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/tipc/socket.c b/net/tipc/socket.c index cebcc104dc70..022999e0202d 100644 --- a/net/tipc/socket.c +++ b/net/tipc/socket.c @@ -1265,7 +1265,7 @@ void tipc_sk_mcast_rcv(struct net *net, struct sk_buff_head *arrvq, spin_lock_bh(&inputq->lock); if (skb_peek(arrvq) == skb) { skb_queue_splice_tail_init(&tmpq, inputq); - kfree_skb(__skb_dequeue(arrvq)); + __skb_dequeue(arrvq); } spin_unlock_bh(&inputq->lock); __skb_queue_purge(&tmpq); |