inet_diag: Move byte-code finding up the call-stack

Current code calculates it at fixed offset. This offset will change, so
move the BC calculation upper to make the further patching simpler.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 17 insertions, 19 deletions

diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
index eb6bdfa9480c..7aad6ad24dda 100644
--- a/net/ipv4/inet_diag.c
+++ b/net/ipv4/inet_diag.c
@@ -488,15 +488,13 @@ static int inet_diag_bc_audit(const void *bytecode, int bytecode_len)
 
 static int inet_csk_diag_dump(struct sock *sk,
                               struct sk_buff *skb,
-                              struct netlink_callback *cb)
+                              struct netlink_callback *cb,
+                              const struct nlattr *bc)
 {
         struct inet_diag_req *r = NLMSG_DATA(cb->nlh);
 
-        if (nlmsg_attrlen(cb->nlh, sizeof(*r))) {
+        if (bc != NULL) {
                 struct inet_diag_entry entry;
-                const struct nlattr *bc = nlmsg_find_attr(cb->nlh,
-                                                          sizeof(*r),
-                                                          INET_DIAG_REQ_BYTECODE);
                 struct inet_sock *inet = inet_sk(sk);
 
                 entry.family = sk->sk_family;
@@ -527,15 +525,13 @@ static int inet_csk_diag_dump(struct sock *sk,
 
 static int inet_twsk_diag_dump(struct inet_timewait_sock *tw,
                                struct sk_buff *skb,
-                               struct netlink_callback *cb)
+                               struct netlink_callback *cb,
+                               const struct nlattr *bc)
 {
         struct inet_diag_req *r = NLMSG_DATA(cb->nlh);
 
-        if (nlmsg_attrlen(cb->nlh, sizeof(*r))) {
+        if (bc != NULL) {
                 struct inet_diag_entry entry;
-                const struct nlattr *bc = nlmsg_find_attr(cb->nlh,
-                                                          sizeof(*r),
-                                                          INET_DIAG_REQ_BYTECODE);
 
                 entry.family = tw->tw_family;
 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
@@ -616,13 +612,13 @@ nlmsg_failure:
 }
 
 static int inet_diag_dump_reqs(struct sk_buff *skb, struct sock *sk,
-                               struct netlink_callback *cb)
+                               struct netlink_callback *cb,
+                               const struct nlattr *bc)
 {
         struct inet_diag_entry entry;
         struct inet_diag_req *r = NLMSG_DATA(cb->nlh);
         struct inet_connection_sock *icsk = inet_csk(sk);
         struct listen_sock *lopt;
-        const struct nlattr *bc = NULL;
         struct inet_sock *inet = inet_sk(sk);
         int j, s_j;
         int reqnum, s_reqnum;
@@ -642,9 +638,7 @@ static int inet_diag_dump_reqs(struct sk_buff *skb, struct sock *sk,
         if (!lopt || !lopt->qlen)
                 goto out;
 
-        if (nlmsg_attrlen(cb->nlh, sizeof(*r))) {
-                bc = nlmsg_find_attr(cb->nlh, sizeof(*r),
-                                     INET_DIAG_REQ_BYTECODE);
+        if (bc != NULL) {
                 entry.sport = inet->inet_num;
                 entry.userlocks = sk->sk_userlocks;
         }
@@ -708,6 +702,10 @@ static int inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
         struct inet_diag_req *r = NLMSG_DATA(cb->nlh);
         const struct inet_diag_handler *handler;
         struct inet_hashinfo *hashinfo;
+        const struct nlattr *bc = NULL;
+
+        if (nlmsg_attrlen(cb->nlh, sizeof(struct inet_diag_req)))
+                bc = nlmsg_find_attr(cb->nlh, sizeof(*r), INET_DIAG_REQ_BYTECODE);
 
         handler = inet_diag_lock_handler(cb->nlh->nlmsg_type);
         if (IS_ERR(handler))
@@ -747,7 +745,7 @@ static int inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
                                     cb->args[3] > 0)
                                         goto syn_recv;
 
-                                if (inet_csk_diag_dump(sk, skb, cb) < 0) {
+                                if (inet_csk_diag_dump(sk, skb, cb, bc) < 0) {
                                         spin_unlock_bh(&ilb->lock);
                                         goto done;
                                 }
@@ -756,7 +754,7 @@ syn_recv:
                                 if (!(r->idiag_states & TCPF_SYN_RECV))
                                         goto next_listen;
 
-                                if (inet_diag_dump_reqs(skb, sk, cb) < 0) {
+                                if (inet_diag_dump_reqs(skb, sk, cb, bc) < 0) {
                                         spin_unlock_bh(&ilb->lock);
                                         goto done;
                                 }
@@ -809,7 +807,7 @@ skip_listen_ht:
                         if (r->id.idiag_dport != inet->inet_dport &&
                             r->id.idiag_dport)
                                 goto next_normal;
-                        if (inet_csk_diag_dump(sk, skb, cb) < 0) {
+                        if (inet_csk_diag_dump(sk, skb, cb, bc) < 0) {
                                 spin_unlock_bh(lock);
                                 goto done;
                         }
@@ -831,7 +829,7 @@ next_normal:
                                 if (r->id.idiag_dport != tw->tw_dport &&
                                     r->id.idiag_dport)
                                         goto next_dying;
-                                if (inet_twsk_diag_dump(tw, skb, cb) < 0) {
+                                if (inet_twsk_diag_dump(tw, skb, cb, bc) < 0) {
                                         spin_unlock_bh(lock);
                                         goto done;
                                 }