From e97d09277b7730f85427969115c4ea358bcc2703 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Tue, 4 Sep 2018 16:01:47 +0200 Subject: [PATCH] netfilter: nf_tables: avoid BUG_ON usage [ Upstream commit fa5950e498e7face21a1761f327e6c1152f778c3 ] None of these spots really needs to crash the kernel. In one two cases we can jsut report error to userspace, in the other cases we can just use WARN_ON (and leak memory instead). Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- net/netfilter/nf_tables_api.c | 9 ++++++--- net/netfilter/nft_cmp.c | 6 ++++-- net/netfilter/nft_reject.c | 6 ++++-- 3 files changed, 14 insertions(+), 7 deletions(-) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 24fddf0..289d079 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -1031,7 +1031,8 @@ static int nf_tables_deltable(struct net *net, struct sock *nlsk, static void nf_tables_table_destroy(struct nft_ctx *ctx) { - BUG_ON(ctx->table->use > 0); + if (WARN_ON(ctx->table->use > 0)) + return; rhltable_destroy(&ctx->table->chains_ht); kfree(ctx->table->name); @@ -1446,7 +1447,8 @@ static void nf_tables_chain_destroy(struct nft_ctx *ctx) { struct nft_chain *chain = ctx->chain; - BUG_ON(chain->use > 0); + if (WARN_ON(chain->use > 0)) + return; /* no concurrent access possible anymore */ nf_tables_chain_free_chain_rules(chain); @@ -7253,7 +7255,8 @@ int __nft_release_basechain(struct nft_ctx *ctx) { struct nft_rule *rule, *nr; - BUG_ON(!nft_is_base_chain(ctx->chain)); + if (WARN_ON(!nft_is_base_chain(ctx->chain))) + return 0; nf_tables_unregister_hook(ctx->net, ctx->chain->table, ctx->chain); list_for_each_entry_safe(rule, nr, &ctx->chain->rules, list) { diff --git a/net/netfilter/nft_cmp.c b/net/netfilter/nft_cmp.c index fa90a84..79d48c1 100644 --- a/net/netfilter/nft_cmp.c +++ b/net/netfilter/nft_cmp.c @@ -79,7 +79,8 @@ static int nft_cmp_init(const struct nft_ctx *ctx, const struct nft_expr *expr, err = nft_data_init(NULL, &priv->data, sizeof(priv->data), &desc, tb[NFTA_CMP_DATA]); - BUG_ON(err < 0); + if (err < 0) + return err; priv->sreg = nft_parse_register(tb[NFTA_CMP_SREG]); err = nft_validate_register_load(priv->sreg, desc.len); @@ -129,7 +130,8 @@ static int nft_cmp_fast_init(const struct nft_ctx *ctx, err = nft_data_init(NULL, &data, sizeof(data), &desc, tb[NFTA_CMP_DATA]); - BUG_ON(err < 0); + if (err < 0) + return err; priv->sreg = nft_parse_register(tb[NFTA_CMP_SREG]); err = nft_validate_register_load(priv->sreg, desc.len); diff --git a/net/netfilter/nft_reject.c b/net/netfilter/nft_reject.c index 29f5bd2..b48e58c 100644 --- a/net/netfilter/nft_reject.c +++ b/net/netfilter/nft_reject.c @@ -94,7 +94,8 @@ static u8 icmp_code_v4[NFT_REJECT_ICMPX_MAX + 1] = { int nft_reject_icmp_code(u8 code) { - BUG_ON(code > NFT_REJECT_ICMPX_MAX); + if (WARN_ON_ONCE(code > NFT_REJECT_ICMPX_MAX)) + return ICMP_NET_UNREACH; return icmp_code_v4[code]; } @@ -111,7 +112,8 @@ static u8 icmp_code_v6[NFT_REJECT_ICMPX_MAX + 1] = { int nft_reject_icmpv6_code(u8 code) { - BUG_ON(code > NFT_REJECT_ICMPX_MAX); + if (WARN_ON_ONCE(code > NFT_REJECT_ICMPX_MAX)) + return ICMPV6_NOROUTE; return icmp_code_v6[code]; } -- 2.7.4