netfilter: x_tables: assert minimum target size
commit a08e4e190b866579896c09af59b3bdca821da2cd upstream.
The target size includes the size of the xt_entry_target struct.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c
index 24a9dfb..e3e2dd4 100644
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -567,6 +567,9 @@
return -EINVAL;
t = (void *)(e + target_offset);
+ if (t->u.target_size < sizeof(*t))
+ return -EINVAL;
+
if (target_offset + t->u.target_size > next_offset)
return -EINVAL;