From 7840b9224d5b84c41a8f5a5ddd919c7f7614901f Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Tue, 28 Jul 2020 19:32:44 +0200 Subject: evaluate: remove table from cache on delete table The following ruleset crashes nft if loaded twice, via nft -ef: add table inet filter delete table inet filter table inet filter { chain input { type filter hook input priority filter; policy drop; iifname { "eth0" } counter accept } } If the table contains anonymous sets, such as __set0, then delete + add table might result in nft reusing the existing stale __set0 in the cache. The problem is that nft gets confused and it reuses the existing stale __set0 instead of the new anonymous set __set0 with the same name. Signed-off-by: Pablo Neira Ayuso --- src/evaluate.c | 15 +++++++++++++++ tests/shell/testcases/sets/0053echo_0 | 16 ++++++++++++++++ tests/shell/testcases/sets/dumps/0053echo_0.nft | 6 ++++++ 3 files changed, 37 insertions(+) create mode 100755 tests/shell/testcases/sets/0053echo_0 create mode 100644 tests/shell/testcases/sets/dumps/0053echo_0.nft diff --git a/src/evaluate.c b/src/evaluate.c index 26d73959..a84e9609 100644 --- a/src/evaluate.c +++ b/src/evaluate.c @@ -4172,6 +4172,18 @@ static int cmd_evaluate_add(struct eval_ctx *ctx, struct cmd *cmd) } } +static void table_del_cache(struct eval_ctx *ctx, struct cmd *cmd) +{ + struct table *table; + + table = table_lookup(&cmd->handle, &ctx->nft->cache); + if (!table) + return; + + list_del(&table->list); + table_free(table); +} + static int cmd_evaluate_delete(struct eval_ctx *ctx, struct cmd *cmd) { switch (cmd->obj) { @@ -4180,7 +4192,10 @@ static int cmd_evaluate_delete(struct eval_ctx *ctx, struct cmd *cmd) case CMD_OBJ_SET: case CMD_OBJ_RULE: case CMD_OBJ_CHAIN: + return 0; case CMD_OBJ_TABLE: + table_del_cache(ctx, cmd); + return 0; case CMD_OBJ_FLOWTABLE: case CMD_OBJ_COUNTER: case CMD_OBJ_QUOTA: diff --git a/tests/shell/testcases/sets/0053echo_0 b/tests/shell/testcases/sets/0053echo_0 new file mode 100755 index 00000000..6bb03c28 --- /dev/null +++ b/tests/shell/testcases/sets/0053echo_0 @@ -0,0 +1,16 @@ +#!/bin/bash + +set -e + +EXPECTED="add table inet filter +delete table inet filter + +table inet filter { + chain input { + type filter hook input priority filter; policy drop; + iifname { lo } ip saddr { 10.0.0.0/8 } ip daddr { 192.168.100.62 } tcp dport { 2001 } counter accept + } +} +" + +$NFT -ef - <<< "$EXPECTED" diff --git a/tests/shell/testcases/sets/dumps/0053echo_0.nft b/tests/shell/testcases/sets/dumps/0053echo_0.nft new file mode 100644 index 00000000..6a816636 --- /dev/null +++ b/tests/shell/testcases/sets/dumps/0053echo_0.nft @@ -0,0 +1,6 @@ +table inet filter { + chain input { + type filter hook input priority filter; policy drop; + iifname { "lo" } ip saddr { 10.0.0.0/8 } ip daddr { 192.168.100.62 } tcp dport { 2001 } counter packets 0 bytes 0 accept + } +} -- cgit v1.2.3