[PATCH -next] netfilter: ctnetlink: Fix memleak in ctnetlink_alloc_filter

[Zheng Bin]

ctnetlink_alloc_filter
  filter = kzalloc

  In the following process(such as ctnetlink_parse_zone,
  ctnetlink_parse_filter), if return fail, need to kfree filter.

Fixes: cb8aa9a3affb ("netfilter: ctnetlink: add kernel side filtering for dump")
Signed-off-by: Zheng Bin <zhengbi...@huawei.com>
---
 net/netfilter/nf_conntrack_netlink.c | 27 ++++++++++++++++++---------
 1 file changed, 18 insertions(+), 9 deletions(-)

diff --git a/net/netfilter/nf_conntrack_netlink.c 
b/net/netfilter/nf_conntrack_netlink.c
index d7bd8b1f27d5..f7fdd91ece6d 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -939,7 +939,8 @@ ctnetlink_alloc_filter(const struct nlattr * const cda[], 
u8 family)
                        filter->mark.mask = 0xffffffff;
                }
        } else if (cda[CTA_MARK_MASK]) {
-               return ERR_PTR(-EINVAL);
+               err = -EINVAL;
+               goto error;
        }
 #endif
        if (!cda[CTA_FILTER])
@@ -947,15 +948,17 @@ ctnetlink_alloc_filter(const struct nlattr * const cda[], 
u8 family)

        err = ctnetlink_parse_zone(cda[CTA_ZONE], &filter->zone);
        if (err < 0)
-               return ERR_PTR(err);
+               goto error;

        err = ctnetlink_parse_filter(cda[CTA_FILTER], filter);
        if (err < 0)
-               return ERR_PTR(err);
+               goto error;

        if (filter->orig_flags) {
-               if (!cda[CTA_TUPLE_ORIG])
-                       return ERR_PTR(-EINVAL);
+               if (!cda[CTA_TUPLE_ORIG]) {
+                       err = -EINVAL;
+                       goto error;
+               }

                err = ctnetlink_parse_tuple_filter(cda, &filter->orig,
                                                   CTA_TUPLE_ORIG,
@@ -963,12 +966,14 @@ ctnetlink_alloc_filter(const struct nlattr * const cda[], 
u8 family)
                                                   &filter->zone,
                                                   filter->orig_flags);
                if (err < 0)
-                       return ERR_PTR(err);
+                       goto error;
        }

        if (filter->reply_flags) {
-               if (!cda[CTA_TUPLE_REPLY])
-                       return ERR_PTR(-EINVAL);
+               if (!cda[CTA_TUPLE_REPLY]) {
+                       err = -EINVAL;
+                       goto error;
+               }

                err = ctnetlink_parse_tuple_filter(cda, &filter->reply,
                                                   CTA_TUPLE_REPLY,
@@ -976,10 +981,14 @@ ctnetlink_alloc_filter(const struct nlattr * const cda[], 
u8 family)
                                                   &filter->zone,
                                                   filter->orig_flags);
                if (err < 0)
-                       return ERR_PTR(err);
+                       goto error;
        }

        return filter;
+
+error:
+       kfree(filter);
+       return ERR_PTR(err);
 }

 static bool ctnetlink_needs_filter(u8 family, const struct nlattr * const *cda)
--
2.26.0.106.g9fadedd