Question

使用netlink_kernel_create()创建netlink套接字时，函数指针作为参数传递给此函数，该函数在此套接字上收到消息时调用。此回调函数接收sk_buff作为参数，其中包含收到的消息。

我的问题是，谁负责释放这个sk_buff？

示例代码

#include＆lt; linux / module.h＆gt;
  #include＆lt; net / sock.h＆gt;
  #include＆lt; linux / netlink.h＆gt;
  #include＆lt; linux / skbuff.h＆gt;

#define NETLINK_USER 31

struct sock * nl_sk = NULL;

static void my_nl_recv_msg（struct sk_buff * skb）{

struct nlmsghdr *nlh;  
int pid;  

printk(KERN_INFO "Entering: %s\n", __FUNCTION__);  

nlh=(struct nlmsghdr*)skb->data;  
printk(KERN_INFO "Netlink received msg payload: %s\n",  
    (char*)NLMSG_DATA(nlh));  
pid = nlh->nlmsg_pid; /*pid of sending process */  
NETLINK_CB(skb).dst_group = 0; /* not in mcast group */  
NETLINK_CB(skb).pid = 0;      /* from kernel */  
//printk("About to send msg bak:\n");  
//netlink_unicast(nl_sk,skb,pid,MSG_DONTWAIT);

}

static int __init hello_init（void）{

printk("Entering: %s\n",__FUNCTION__);  
nl_sk=netlink_kernel_create(&init_net, NETLINK_USER, 0,  
        my_nl_recv_msg, NULL, THIS_MODULE);  
if(!nl_sk)  
{  
    printk(KERN_ALERT "Error creating socket.\n");  
    return -10;  
}  
return 0;

}

Answer 1

net/netlink/af_netlink.c：netlink_unicast_kernel，my_nl_recv_msg函数的调用者将负责释放它。

谁的责任是释放sk_buff

示例代码

1 个答案: