diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/netfilter/nf_tables_api.c | 69 |
1 files changed, 65 insertions, 4 deletions
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index c46b1bb0efe0..a9f6babcc781 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -123,6 +123,29 @@ static void nft_validate_state_update(struct nft_table *table, u8 new_validate_s table->validate_state = new_validate_state; } + +static bool nft_chain_vstate_valid(const struct nft_ctx *ctx, + const struct nft_chain *chain) +{ + const struct nft_base_chain *base_chain; + enum nft_chain_types type; + u8 hooknum; + + if (WARN_ON_ONCE(!nft_is_base_chain(ctx->chain))) + return false; + + base_chain = nft_base_chain(ctx->chain); + hooknum = base_chain->ops.hooknum; + type = base_chain->type->type; + + /* chain is already validated for this call depth */ + if (chain->vstate.depth >= ctx->level && + chain->vstate.hook_mask[type] & BIT(hooknum)) + return true; + + return false; +} + static void nf_tables_trans_destroy_work(struct work_struct *w); static void nft_trans_gc_work(struct work_struct *work); @@ -4079,6 +4102,29 @@ static void nf_tables_rule_release(const struct nft_ctx *ctx, struct nft_rule *r nf_tables_rule_destroy(ctx, rule); } +static void nft_chain_vstate_update(const struct nft_ctx *ctx, struct nft_chain *chain) +{ + const struct nft_base_chain *base_chain; + enum nft_chain_types type; + u8 hooknum; + + /* ctx->chain must hold the calling base chain. */ + if (WARN_ON_ONCE(!nft_is_base_chain(ctx->chain))) { + memset(&chain->vstate, 0, sizeof(chain->vstate)); + return; + } + + base_chain = nft_base_chain(ctx->chain); + hooknum = base_chain->ops.hooknum; + type = base_chain->type->type; + + BUILD_BUG_ON(BIT(NF_INET_NUMHOOKS) > U8_MAX); + + chain->vstate.hook_mask[type] |= BIT(hooknum); + if (chain->vstate.depth < ctx->level) + chain->vstate.depth = ctx->level; +} + /** nft_chain_validate - loop detection and hook validation * * @ctx: context containing call depth and base chain @@ -4088,15 +4134,25 @@ static void nf_tables_rule_release(const struct nft_ctx *ctx, struct nft_rule *r * and set lookups until either the jump limit is hit or all reachable * chains have been validated. */ -int nft_chain_validate(const struct nft_ctx *ctx, const struct nft_chain *chain) +int nft_chain_validate(const struct nft_ctx *ctx, struct nft_chain *chain) { struct nft_expr *expr, *last; struct nft_rule *rule; int err; + BUILD_BUG_ON(NFT_JUMP_STACK_SIZE > 255); if (ctx->level == NFT_JUMP_STACK_SIZE) return -EMLINK; + if (ctx->level > 0) { + /* jumps to base chains are not allowed. */ + if (nft_is_base_chain(chain)) + return -ELOOP; + + if (nft_chain_vstate_valid(ctx, chain)) + return 0; + } + list_for_each_entry(rule, &chain->rules, list) { if (fatal_signal_pending(current)) return -EINTR; @@ -4117,6 +4173,7 @@ int nft_chain_validate(const struct nft_ctx *ctx, const struct nft_chain *chain) } } + nft_chain_vstate_update(ctx, chain); return 0; } EXPORT_SYMBOL_GPL(nft_chain_validate); @@ -4128,7 +4185,7 @@ static int nft_table_validate(struct net *net, const struct nft_table *table) .net = net, .family = table->family, }; - int err; + int err = 0; list_for_each_entry(chain, &table->chains, list) { if (!nft_is_base_chain(chain)) @@ -4137,12 +4194,16 @@ static int nft_table_validate(struct net *net, const struct nft_table *table) ctx.chain = chain; err = nft_chain_validate(&ctx, chain); if (err < 0) - return err; + goto err; cond_resched(); } - return 0; +err: + list_for_each_entry(chain, &table->chains, list) + memset(&chain->vstate, 0, sizeof(chain->vstate)); + + return err; } int nft_setelem_validate(const struct nft_ctx *ctx, struct nft_set *set, |