From 753c111f655e38bbd52fc01321266633f022ebe2 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Wed, 13 Feb 2019 13:03:53 +0100 Subject: [PATCH] netfilter: nft_compat: use-after-free when deleting targets Fetch pointer to module before target object is released. Fixes: 29e3880109e3 ("netfilter: nf_tables: fix use-after-free when deleting compat expressions") Fixes: 0ca743a55991 ("netfilter: nf_tables: add compatibility layer for x_tables") Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_compat.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/netfilter/nft_compat.c b/net/netfilter/nft_compat.c index fe64df848365..0a4bad55a8aa 100644 --- a/net/netfilter/nft_compat.c +++ b/net/netfilter/nft_compat.c @@ -315,6 +315,7 @@ nft_target_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr) { struct xt_target *target = expr->ops->data; void *info = nft_expr_priv(expr); + struct module *me = target->me; struct xt_tgdtor_param par; par.net = ctx->net; @@ -325,7 +326,7 @@ nft_target_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr) par.target->destroy(&par); if (nft_xt_put(container_of(expr->ops, struct nft_xt, ops))) - module_put(target->me); + module_put(me); } static int nft_extension_dump_info(struct sk_buff *skb, int attr,