net: introduce helper macro for_each_cmsghdr

Introduce helper macro for_each_cmsghdr as a wrapper of the enumerating
cmsghdr from msghdr, just cleanup.

Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

8 files changed, 10 insertions, 15 deletions

diff --git a/net/core/scm.c b/net/core/scm.c
index b442e7e25e60..3b6899b7d810 100644
--- a/net/core/scm.c
+++ b/net/core/scm.c
@@ -129,8 +129,7 @@ int __scm_send(struct socket *sock, struct msghdr *msg, struct scm_cookie *p)
         struct cmsghdr *cmsg;
         int err;
 
-        for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg))
-        {
+        for_each_cmsghdr(cmsg, msg) {
                 err = -EINVAL;
 
                 /* Verify that cmsg_len is at least sizeof(struct cmsghdr) */
diff --git a/net/dccp/proto.c b/net/dccp/proto.c
index 19f038739087..e171b780b499 100644
--- a/net/dccp/proto.c
+++ b/net/dccp/proto.c
@@ -703,7 +703,7 @@ EXPORT_SYMBOL_GPL(compat_dccp_getsockopt);
 
 static int dccp_msghdr_parse(struct msghdr *msg, struct sk_buff *skb)
 {
-        struct cmsghdr *cmsg = CMSG_FIRSTHDR(msg);
+        struct cmsghdr *cmsg;
 
         /*
          * Assign an (opaque) qpolicy priority value to skb->priority.
@@ -717,8 +717,7 @@ static int dccp_msghdr_parse(struct msghdr *msg, struct sk_buff *skb)
          */
         skb->priority = 0;
 
-        for (; cmsg != NULL; cmsg = CMSG_NXTHDR(msg, cmsg)) {
-
+        for_each_cmsghdr(cmsg, msg) {
                 if (!CMSG_OK(msg, cmsg))
                         return -EINVAL;
 
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 640f26c6a9fe..8a89c738b7a3 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -192,7 +192,7 @@ int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc,
         int err, val;
         struct cmsghdr *cmsg;
 
-        for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
+        for_each_cmsghdr(cmsg, msg) {
                 if (!CMSG_OK(msg, cmsg))
                         return -EINVAL;
 #if IS_ENABLED(CONFIG_IPV6)
diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c
index 2464a00e36ab..100c589a2a6c 100644
--- a/net/ipv6/datagram.c
+++ b/net/ipv6/datagram.c
@@ -657,7 +657,7 @@ int ip6_datagram_send_ctl(struct net *net, struct sock *sk,
         int len;
         int err = 0;
 
-        for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
+        for_each_cmsghdr(cmsg, msg) {
                 int addr_type;
 
                 if (!CMSG_OK(msg, cmsg)) {
diff --git a/net/iucv/af_iucv.c b/net/iucv/af_iucv.c
index 1cd3f8107239..2e9953b2db84 100644
--- a/net/iucv/af_iucv.c
+++ b/net/iucv/af_iucv.c
@@ -1070,9 +1070,7 @@ static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
         txmsg.class = 0;
 
         /* iterate over control messages */
-        for (cmsg = CMSG_FIRSTHDR(msg); cmsg;
-                cmsg = CMSG_NXTHDR(msg, cmsg)) {
-
+        for_each_cmsghdr(cmsg, msg) {
                 if (!CMSG_OK(msg, cmsg)) {
                         err = -EINVAL;
                         goto out;
diff --git a/net/rds/send.c b/net/rds/send.c
index 40a5629a0a13..42f65d4305c8 100644
--- a/net/rds/send.c
+++ b/net/rds/send.c
@@ -826,7 +826,7 @@ static int rds_rm_size(struct msghdr *msg, int data_len)
         int cmsg_groups = 0;
         int retval;
 
-        for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
+        for_each_cmsghdr(cmsg, msg) {
                 if (!CMSG_OK(msg, cmsg))
                         return -EINVAL;
 
@@ -878,7 +878,7 @@ static int rds_cmsg_send(struct rds_sock *rs, struct rds_message *rm,
         struct cmsghdr *cmsg;
         int ret = 0;
 
-        for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
+        for_each_cmsghdr(cmsg, msg) {
                 if (!CMSG_OK(msg, cmsg))
                         return -EINVAL;
 
diff --git a/net/rxrpc/ar-output.c b/net/rxrpc/ar-output.c
index 86e0f10aa2c0..e1a9373e5979 100644
--- a/net/rxrpc/ar-output.c
+++ b/net/rxrpc/ar-output.c
@@ -45,7 +45,7 @@ static int rxrpc_sendmsg_cmsg(struct rxrpc_sock *rx, struct msghdr *msg,
         if (msg->msg_controllen == 0)
                 return -EINVAL;
 
-        for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
+        for_each_cmsghdr(cmsg, msg) {
                 if (!CMSG_OK(msg, cmsg))
                         return -EINVAL;
 
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index c92f96cda699..2625eccb77d5 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -6592,8 +6592,7 @@ static int sctp_msghdr_parse(const struct msghdr *msg, sctp_cmsgs_t *cmsgs)
         struct cmsghdr *cmsg;
         struct msghdr *my_msg = (struct msghdr *)msg;
 
-        for (cmsg = CMSG_FIRSTHDR(msg); cmsg != NULL;
-             cmsg = CMSG_NXTHDR(my_msg, cmsg)) {
+        for_each_cmsghdr(cmsg, my_msg) {
                 if (!CMSG_OK(my_msg, cmsg))
                         return -EINVAL;