net_sched: act: Dont increment refcnt on replace

 This is a bug fix. The existing code tries to kill many
 birds with one stone: Handling binding of actions to
 filters, new actions and replacing of action
 attributes. A simple test case to illustrate:

XXXX
 moja@fe1:~$ sudo tc actions add action drop index 12
 moja@fe1:~$ actions get action gact index 12
 action order 1: gact action drop
  random type none pass val 0
  index 12 ref 1 bind 0
 moja@fe1:~$ sudo tc actions replace action ok index 12
 moja@fe1:~$ actions get action gact index 12
 action order 1: gact action drop
  random type none pass val 0
  index 12 ref 2 bind 0
XXXX

The above shows the refcounf being wrongly incremented on replace.
There are more complex scenarios with binding of actions to filters
that i am leaving out that didnt work as well...

Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

8 files changed, 37 insertions, 26 deletions

diff --git a/net/sched/act_csum.c b/net/sched/act_csum.c
index 5c5edf56adbd..11fe1a416433 100644
--- a/net/sched/act_csum.c
+++ b/net/sched/act_csum.c
@@ -77,16 +77,16 @@ static int tcf_csum_init(struct net *n, struct nlattr *nla, struct nlattr *est,
                                      &csum_idx_gen, &csum_hash_info);
                 if (IS_ERR(pc))
                         return PTR_ERR(pc);
-                p = to_tcf_csum(pc);
                 ret = ACT_P_CREATED;
         } else {
-                p = to_tcf_csum(pc);
-                if (!ovr) {
-                        tcf_hash_release(pc, bind, &csum_hash_info);
+                if (bind)/* dont override defaults */
+                        return 0;
+                tcf_hash_release(pc, bind, &csum_hash_info);
+                if (!ovr)
                         return -EEXIST;
-                }
         }
 
+        p = to_tcf_csum(pc);
         spin_lock_bh(&p->tcf_lock);
         p->tcf_action = parm->action;
         p->update_flags = parm->update_flags;
diff --git a/net/sched/act_gact.c b/net/sched/act_gact.c
index 5645a4d32abd..eb9ba60ebab4 100644
--- a/net/sched/act_gact.c
+++ b/net/sched/act_gact.c
@@ -102,10 +102,11 @@ static int tcf_gact_init(struct net *net, struct nlattr *nla,
                         return PTR_ERR(pc);
                 ret = ACT_P_CREATED;
         } else {
-                if (!ovr) {
-                        tcf_hash_release(pc, bind, &gact_hash_info);
+                if (bind)/* dont override defaults */
+                        return 0;
+                tcf_hash_release(pc, bind, &gact_hash_info);
+                if (!ovr)
                         return -EEXIST;
-                }
         }
 
         gact = to_gact(pc);
diff --git a/net/sched/act_ipt.c b/net/sched/act_ipt.c
index 882a89762f77..dcbfe8ce04a6 100644
--- a/net/sched/act_ipt.c
+++ b/net/sched/act_ipt.c
@@ -141,10 +141,12 @@ static int tcf_ipt_init(struct net *net, struct nlattr *nla, struct nlattr *est,
                         return PTR_ERR(pc);
                 ret = ACT_P_CREATED;
         } else {
-                if (!ovr) {
-                        tcf_ipt_release(to_ipt(pc), bind);
+                if (bind)/* dont override defaults */
+                        return 0;
+                tcf_ipt_release(to_ipt(pc), bind);
+
+                if (!ovr)
                         return -EEXIST;
-                }
         }
         ipt = to_ipt(pc);
 
diff --git a/net/sched/act_nat.c b/net/sched/act_nat.c
index 6a15ace00241..76869538d028 100644
--- a/net/sched/act_nat.c
+++ b/net/sched/act_nat.c
@@ -70,15 +70,15 @@ static int tcf_nat_init(struct net *net, struct nlattr *nla, struct nlattr *est,
                                      &nat_idx_gen, &nat_hash_info);
                 if (IS_ERR(pc))
                         return PTR_ERR(pc);
-                p = to_tcf_nat(pc);
                 ret = ACT_P_CREATED;
         } else {
-                p = to_tcf_nat(pc);
-                if (!ovr) {
-                        tcf_hash_release(pc, bind, &nat_hash_info);
+                if (bind)
+                        return 0;
+                tcf_hash_release(pc, bind, &nat_hash_info);
+                if (!ovr)
                         return -EEXIST;
-                }
         }
+        p = to_tcf_nat(pc);
 
         spin_lock_bh(&p->tcf_lock);
         p->old_addr = parm->old_addr;
diff --git a/net/sched/act_pedit.c b/net/sched/act_pedit.c
index 03b67674169c..7aa2dcd989f8 100644
--- a/net/sched/act_pedit.c
+++ b/net/sched/act_pedit.c
@@ -84,10 +84,12 @@ static int tcf_pedit_init(struct net *net, struct nlattr *nla,
                 ret = ACT_P_CREATED;
         } else {
                 p = to_pedit(pc);
-                if (!ovr) {
-                        tcf_hash_release(pc, bind, &pedit_hash_info);
+                tcf_hash_release(pc, bind, &pedit_hash_info);
+                if (bind)
+                        return 0;
+                if (!ovr)
                         return -EEXIST;
-                }
+
                 if (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys) {
                         keys = kmalloc(ksize, GFP_KERNEL);
                         if (keys == NULL)
diff --git a/net/sched/act_police.c b/net/sched/act_police.c
index 16a62c36928a..ef246d87e68b 100644
--- a/net/sched/act_police.c
+++ b/net/sched/act_police.c
@@ -177,10 +177,12 @@ static int tcf_act_police_locate(struct net *net, struct nlattr *nla,
                         if (bind) {
                                 police->tcf_bindcnt += 1;
                                 police->tcf_refcnt += 1;
+                                return 0;
                         }
                         if (ovr)
                                 goto override;
-                        return ret;
+                        /* not replacing */
+                        return -EEXIST;
                 }
         }
 
diff --git a/net/sched/act_simple.c b/net/sched/act_simple.c
index 31157d3e729c..f7b45ab85388 100644
--- a/net/sched/act_simple.c
+++ b/net/sched/act_simple.c
@@ -142,10 +142,13 @@ static int tcf_simp_init(struct net *net, struct nlattr *nla,
                 ret = ACT_P_CREATED;
         } else {
                 d = to_defact(pc);
-                if (!ovr) {
-                        tcf_simp_release(d, bind);
+
+                if (bind)
+                        return 0;
+                tcf_simp_release(d, bind);
+                if (!ovr)
                         return -EEXIST;
-                }
+
                 reset_policy(d, defdata, parm);
         }
 
diff --git a/net/sched/act_skbedit.c b/net/sched/act_skbedit.c
index 35ea643b4325..8fe9d25c3008 100644
--- a/net/sched/act_skbedit.c
+++ b/net/sched/act_skbedit.c
@@ -120,10 +120,11 @@ static int tcf_skbedit_init(struct net *net, struct nlattr *nla,
                 ret = ACT_P_CREATED;
         } else {
                 d = to_skbedit(pc);
-                if (!ovr) {
-                        tcf_hash_release(pc, bind, &skbedit_hash_info);
+                if (bind)
+                        return 0;
+                tcf_hash_release(pc, bind, &skbedit_hash_info);
+                if (!ovr)
                         return -EEXIST;
-                }
         }
 
         spin_lock_bh(&d->tcf_lock);