[NET_SCHED]: Use nla_nest_start/nla_nest_end

Use nla_nest_start/nla_nest_end for dumping nested attributes.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 46 insertions, 38 deletions

diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index 87818d7fb623..36022605fc16 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -69,7 +69,7 @@ static int tcf_dump_walker(struct sk_buff *skb, struct netlink_callback *cb,
 {
         struct tcf_common *p;
         int err = 0, index = -1,i = 0, s_i = 0, n_i = 0;
-        struct nlattr *r ;
+        struct nlattr *nest;
 
         read_lock_bh(hinfo->lock);
 
@@ -84,15 +84,17 @@ static int tcf_dump_walker(struct sk_buff *skb, struct netlink_callback *cb,
                                 continue;
                         a->priv = p;
                         a->order = n_i;
-                        r = (struct nlattr *)skb_tail_pointer(skb);
-                        NLA_PUT(skb, a->order, 0, NULL);
+
+                        nest = nla_nest_start(skb, a->order);
+                        if (nest == NULL)
+                                goto nla_put_failure;
                         err = tcf_action_dump_1(skb, a, 0, 0);
                         if (err < 0) {
                                 index--;
-                                nlmsg_trim(skb, r);
+                                nlmsg_trim(skb, nest);
                                 goto done;
                         }
-                        r->nla_len = skb_tail_pointer(skb) - (u8 *)r;
+                        nla_nest_end(skb, nest);
                         n_i++;
                         if (n_i >= TCA_ACT_MAX_PRIO)
                                 goto done;
@@ -105,7 +107,7 @@ done:
         return n_i;
 
 nla_put_failure:
-        nlmsg_trim(skb, r);
+        nla_nest_cancel(skb, nest);
         goto done;
 }
 
@@ -113,11 +115,12 @@ static int tcf_del_walker(struct sk_buff *skb, struct tc_action *a,
                           struct tcf_hashinfo *hinfo)
 {
         struct tcf_common *p, *s_p;
-        struct nlattr *r ;
+        struct nlattr *nest;
         int i= 0, n_i = 0;
 
-        r = (struct nlattr *)skb_tail_pointer(skb);
-        NLA_PUT(skb, a->order, 0, NULL);
+        nest = nla_nest_start(skb, a->order);
+        if (nest == NULL)
+                goto nla_put_failure;
         NLA_PUT(skb, TCA_KIND, IFNAMSIZ, a->ops->kind);
         for (i = 0; i < (hinfo->hmask + 1); i++) {
                 p = hinfo->htab[tcf_hash(i, hinfo->hmask)];
@@ -131,11 +134,11 @@ static int tcf_del_walker(struct sk_buff *skb, struct tc_action *a,
                 }
         }
         NLA_PUT(skb, TCA_FCNT, 4, &n_i);
-        r->nla_len = skb_tail_pointer(skb) - (u8 *)r;
+        nla_nest_end(skb, nest);
 
         return n_i;
 nla_put_failure:
-        nlmsg_trim(skb, r);
+        nla_nest_cancel(skb, nest);
         return -EINVAL;
 }
 
@@ -415,7 +418,7 @@ tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 {
         int err = -EINVAL;
         unsigned char *b = skb_tail_pointer(skb);
-        struct nlattr *r;
+        struct nlattr *nest;
 
         if (a->ops == NULL || a->ops->dump == NULL)
                 return err;
@@ -423,10 +426,11 @@ tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
         NLA_PUT(skb, TCA_KIND, IFNAMSIZ, a->ops->kind);
         if (tcf_action_copy_stats(skb, a, 0))
                 goto nla_put_failure;
-        r = (struct nlattr *)skb_tail_pointer(skb);
-        NLA_PUT(skb, TCA_OPTIONS, 0, NULL);
+        nest = nla_nest_start(skb, TCA_OPTIONS);
+        if (nest == NULL)
+                goto nla_put_failure;
         if ((err = tcf_action_dump_old(skb, a, bind, ref)) > 0) {
-                r->nla_len = skb_tail_pointer(skb) - (u8 *)r;
+                nla_nest_end(skb, nest);
                 return err;
         }
 
@@ -441,17 +445,17 @@ tcf_action_dump(struct sk_buff *skb, struct tc_action *act, int bind, int ref)
 {
         struct tc_action *a;
         int err = -EINVAL;
-        unsigned char *b = skb_tail_pointer(skb);
-        struct nlattr *r ;
+        struct nlattr *nest;
 
         while ((a = act) != NULL) {
-                r = (struct nlattr *)skb_tail_pointer(skb);
                 act = a->next;
-                NLA_PUT(skb, a->order, 0, NULL);
+                nest = nla_nest_start(skb, a->order);
+                if (nest == NULL)
+                        goto nla_put_failure;
                 err = tcf_action_dump_1(skb, a, bind, ref);
                 if (err < 0)
                         goto errout;
-                r->nla_len = skb_tail_pointer(skb) - (u8 *)r;
+                nla_nest_end(skb, nest);
         }
 
         return 0;
@@ -459,7 +463,7 @@ tcf_action_dump(struct sk_buff *skb, struct tc_action *act, int bind, int ref)
 nla_put_failure:
         err = -EINVAL;
 errout:
-        nlmsg_trim(skb, b);
+        nla_nest_cancel(skb, nest);
         return err;
 }
 
@@ -627,7 +631,7 @@ tca_get_fill(struct sk_buff *skb, struct tc_action *a, u32 pid, u32 seq,
         struct tcamsg *t;
         struct nlmsghdr *nlh;
         unsigned char *b = skb_tail_pointer(skb);
-        struct nlattr *x;
+        struct nlattr *nest;
 
         nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*t), flags);
 
@@ -636,13 +640,14 @@ tca_get_fill(struct sk_buff *skb, struct tc_action *a, u32 pid, u32 seq,
         t->tca__pad1 = 0;
         t->tca__pad2 = 0;
 
-        x = (struct nlattr *)skb_tail_pointer(skb);
-        NLA_PUT(skb, TCA_ACT_TAB, 0, NULL);
+        nest = nla_nest_start(skb, TCA_ACT_TAB);
+        if (nest == NULL)
+                goto nla_put_failure;
 
         if (tcf_action_dump(skb, a, bind, ref) < 0)
                 goto nla_put_failure;
 
-        x->nla_len = skb_tail_pointer(skb) - (u8 *)x;
+        nla_nest_end(skb, nest);
 
         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
         return skb->len;
@@ -743,7 +748,7 @@ static int tca_action_flush(struct nlattr *nla, struct nlmsghdr *n, u32 pid)
         struct nlmsghdr *nlh;
         struct tcamsg *t;
         struct netlink_callback dcb;
-        struct nlattr *x;
+        struct nlattr *nest;
         struct nlattr *tb[TCA_ACT_MAX+1];
         struct nlattr *kind;
         struct tc_action *a = create_a(0);
@@ -779,14 +784,15 @@ static int tca_action_flush(struct nlattr *nla, struct nlmsghdr *n, u32 pid)
         t->tca__pad1 = 0;
         t->tca__pad2 = 0;
 
-        x = (struct nlattr *)skb_tail_pointer(skb);
-        NLA_PUT(skb, TCA_ACT_TAB, 0, NULL);
+        nest = nla_nest_start(skb, TCA_ACT_TAB);
+        if (nest == NULL)
+                goto nla_put_failure;
 
         err = a->ops->walk(skb, &dcb, RTM_DELACTION, a);
         if (err < 0)
                 goto nla_put_failure;
 
-        x->nla_len = skb_tail_pointer(skb) - (u8 *)x;
+        nla_nest_end(skb, nest);
 
         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
         nlh->nlmsg_flags |= NLM_F_ROOT;
@@ -875,7 +881,7 @@ static int tcf_add_notify(struct tc_action *a, u32 pid, u32 seq, int event,
         struct tcamsg *t;
         struct nlmsghdr *nlh;
         struct sk_buff *skb;
-        struct nlattr *x;
+        struct nlattr *nest;
         unsigned char *b;
         int err = 0;
 
@@ -891,13 +897,14 @@ static int tcf_add_notify(struct tc_action *a, u32 pid, u32 seq, int event,
         t->tca__pad1 = 0;
         t->tca__pad2 = 0;
 
-        x = (struct nlattr *)skb_tail_pointer(skb);
-        NLA_PUT(skb, TCA_ACT_TAB, 0, NULL);
+        nest = nla_nest_start(skb, TCA_ACT_TAB);
+        if (nest == NULL)
+                goto nla_put_failure;
 
         if (tcf_action_dump(skb, a, 0, 0) < 0)
                 goto nla_put_failure;
 
-        x->nla_len = skb_tail_pointer(skb) - (u8 *)x;
+        nla_nest_end(skb, nest);
 
         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
         NETLINK_CB(skb).dst_group = RTNLGRP_TC;
@@ -1025,7 +1032,7 @@ tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
         struct net *net = skb->sk->sk_net;
         struct nlmsghdr *nlh;
         unsigned char *b = skb_tail_pointer(skb);
-        struct nlattr *x;
+        struct nlattr *nest;
         struct tc_action_ops *a_o;
         struct tc_action a;
         int ret = 0;
@@ -1060,18 +1067,19 @@ tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
         t->tca__pad1 = 0;
         t->tca__pad2 = 0;
 
-        x = (struct nlattr *)skb_tail_pointer(skb);
-        NLA_PUT(skb, TCA_ACT_TAB, 0, NULL);
+        nest = nla_nest_start(skb, TCA_ACT_TAB);
+        if (nest == NULL)
+                goto nla_put_failure;
 
         ret = a_o->walk(skb, cb, RTM_GETACTION, &a);
         if (ret < 0)
                 goto nla_put_failure;
 
         if (ret > 0) {
-                x->nla_len = skb_tail_pointer(skb) - (u8 *)x;
+                nla_nest_end(skb, nest);
                 ret = skb->len;
         } else
-                nlmsg_trim(skb, x);
+                nla_nest_cancel(skb, nest);
 
         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
         if (NETLINK_CB(cb->skb).pid && ret)