From 336f531ab17c3f480f8289d26c35bd48302ed085 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Tue, 14 Jul 2020 13:56:22 +0300 Subject: [PATCH] netfilter: nf_tables: Fix a use after free in nft_immediate_destroy() The nf_tables_rule_release() function frees "rule" so we have to use the _safe() version of list_for_each_entry(). Fixes: d0e2c7de92c7 ("netfilter: nf_tables: add NFT_CHAIN_BINDING") Signed-off-by: Dan Carpenter Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_immediate.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/netfilter/nft_immediate.c b/net/netfilter/nft_immediate.c index 9e556638bb32..c63eb3b17178 100644 --- a/net/netfilter/nft_immediate.c +++ b/net/netfilter/nft_immediate.c @@ -103,9 +103,9 @@ static void nft_immediate_destroy(const struct nft_ctx *ctx, { const struct nft_immediate_expr *priv = nft_expr_priv(expr); const struct nft_data *data = &priv->data; + struct nft_rule *rule, *n; struct nft_ctx chain_ctx; struct nft_chain *chain; - struct nft_rule *rule; if (priv->dreg != NFT_REG_VERDICT) return; @@ -121,7 +121,7 @@ static void nft_immediate_destroy(const struct nft_ctx *ctx, chain_ctx = *ctx; chain_ctx.chain = chain; - list_for_each_entry(rule, &chain->rules, list) + list_for_each_entry_safe(rule, n, &chain->rules, list) nf_tables_rule_release(&chain_ctx, rule); nf_tables_chain_destroy(&chain_ctx);