[NETFILTER]: ipt_recent: avoid a possible NULL pointer deref in recent_seq_open()

If the call to seq_open() returns != 0 then the code calls 
kfree(st) but then on the very next line proceeds to 
dereference the pointer - not good.

Problem spotted by the Coverity checker.

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 1 deletions

diff --git a/net/ipv4/netfilter/ipt_recent.c b/net/ipv4/netfilter/ipt_recent.c
index 321804315659..6d0c0f7364ad 100644
--- a/net/ipv4/netfilter/ipt_recent.c
+++ b/net/ipv4/netfilter/ipt_recent.c
@@ -387,12 +387,17 @@ static int recent_seq_open(struct inode *inode, struct file *file)
         st = kzalloc(sizeof(*st), GFP_KERNEL);
         if (st == NULL)
                 return -ENOMEM;
+
         ret = seq_open(file, &recent_seq_ops);
-        if (ret)
+        if (ret) {
                 kfree(st);
+                goto out;
+        }
+
         st->table    = pde->data;
         seq          = file->private_data;
         seq->private = st;
+out:
         return ret;
 }