From: Michal Kubeček Date: Wed, 11 Sep 2013 08:17:27 +0000 (+0200) Subject: netfilter: nf_conntrack: use RCU safe kfree for conntrack extensions X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=c13a84a830a208fb3443628773c8ca0557773cc7;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git netfilter: nf_conntrack: use RCU safe kfree for conntrack extensions Commit 68b80f11 (netfilter: nf_nat: fix RCU races) introduced RCU protection for freeing extension data when reallocation moves them to a new location. We need the same protection when freeing them in nf_ct_ext_free() in order to prevent a use-after-free by other threads referencing a NAT extension data via bysource list. Signed-off-by: Michal Kubecek Signed-off-by: Pablo Neira Ayuso --- diff --git a/include/net/netfilter/nf_conntrack_extend.h b/include/net/netfilter/nf_conntrack_extend.h index ff95434e50ca..88a1d4060d52 100644 --- a/include/net/netfilter/nf_conntrack_extend.h +++ b/include/net/netfilter/nf_conntrack_extend.h @@ -86,7 +86,7 @@ static inline void nf_ct_ext_destroy(struct nf_conn *ct) static inline void nf_ct_ext_free(struct nf_conn *ct) { if (ct->ext) - kfree(ct->ext); + kfree_rcu(ct->ext, rcu); } /* Add this type, returns pointer to data or NULL. */