[PATCH 4.9 59/71] ping: Check return value of function 'ping_queue_rcv_skb'

Sasha Levin
2021-06-28T15:22:24Z

From: Zheng Yongjun <zhengyongjun3@huawei.com>

[ Upstream commit 9d44fa3e50cc91691896934d106c86e4027e61ca ]

Function 'ping_queue_rcv_skb' not always return success, which will
also return fail. If not check the wrong return value of it, lead to function
`ping_rcv` return success.

Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/ipv4/ping.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c
index 4fda9abf38ee..dd4e46af1e53 100644
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -976,6 +976,7 @@ bool ping_rcv(struct sk_buff *skb)
struct sock *sk;
struct net *net = dev_net(skb->dev);
struct icmphdr *icmph = icmp_hdr(skb);
+ bool rc = false;

/* We assume the packet has already been checked by icmp_rcv */

@@ -990,14 +991,15 @@ bool ping_rcv(struct sk_buff *skb)
struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);

pr_debug("rcv on socket %p\n", sk);
- if (skb2)
- ping_queue_rcv_skb(sk, skb2);
+ if (skb2 && !ping_queue_rcv_skb(sk, skb2))
+ rc = true;
sock_put(sk);
- return true;
}
- pr_debug("no socket, dropping\n");

- return false;
+ if (!rc)
+ pr_debug("no socket, dropping\n");
+
+ return rc;
}
EXPORT_SYMBOL_GPL(ping_rcv);

--
2.30.2