genetlink: fix a memory leak on error path

In __genl_register_family(), when genl_validate_assign_mc_groups()
fails, we forget to free the memory we possibly allocate for
family->attrbuf.

Note, some callers call genl_unregister_family() to clean up
on error path, it doesn't work because the family is inserted
to the global list in the nearly last step.

Cc: Jakub Kicinski <[email protected]>
Cc: Johannes Berg <[email protected]>
Signed-off-by: Cong Wang <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
index 23cc12639ba769ac67714f5e5f5f9549a4417c38..49c28e8ef01b986c068ecc8e86d4d8546088c8f7 100644 (file)
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -404,7 +404,7 @@ int __genl_register_family(struct genl_family *family)
 
        err = genl_validate_assign_mc_groups(family);
        if (err)
-               goto errout_locked;
+               goto errout_free;
 
        list_add_tail(&family->family_list, genl_family_chain(family->id));
        genl_unlock_all();
@@ -417,6 +417,8 @@ int __genl_register_family(struct genl_family *family)
 
        return 0;
 
+errout_free:
+       kfree(family->attrbuf);
 errout_locked:
        genl_unlock_all();
 errout: