答复: [PATCH] ping: Check return value of function 'ping_queue_rcv_skb'
From: zhengyongjun <hidden>
Date: 2021-06-08 01:48:11
Also in:
lkml
Thank you for your suggestion, it will make the code look cleaner :) I will send patch v2 soon. -----邮件原件----- 发件人: David Ahern [mailto:dsahern@gmail.com] 发送时间: 2021年6月8日 0:26 收件人: zhengyongjun [off-list ref]; davem@davemloft.net; yoshfuji@linux-ipv6.org; dsahern@kernel.org; kuba@kernel.org; netdev@vger.kernel.org; linux-kernel@vger.kernel.org 主题: Re: [PATCH] ping: Check return value of function 'ping_queue_rcv_skb' On 6/7/21 3:10 AM, Zheng Yongjun wrote:
quoted hunk ↗ jump to hunk
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 <redacted> --- net/ipv4/ping.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c index1c9f71a37258..8e84cde95011 100644--- a/net/ipv4/ping.c +++ b/net/ipv4/ping.c@@ -968,10 +968,11 @@ 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)) { + sock_put(sk); + return true; + } sock_put(sk); - return true; } pr_debug("no socket, dropping\n");
declare a default return variable: bool rc = false; set to to true if ping_queue_rcv_skb() fails and have one exit path with one sock_put.