diff options
| author | Xiao Liang <shaw.leon@gmail.com> | 2022-08-19 10:40:23 +0800 |
|---|---|---|
| committer | Florian Westphal <fw@strlen.de> | 2022-08-19 08:10:06 +0200 |
| commit | 9a20f17a7a82ce5ba47047e6c3d2fc921cc1087d (patch) | |
| tree | 900a1c2cc23915acba34842bb3a5c6d28a50ef9b /src/evaluate.c | |
| parent | 7526881a6bbf874c0998fc9cea1646b5354596ce (diff) | |
src: Don't parse string as verdict in map
In verdict map, string values are accidentally treated as verdicts.
For example:
table t {
map foo {
type ipv4_addr : verdict
elements = {
192.168.0.1 : bar
}
}
chain output {
type filter hook output priority mangle;
ip daddr vmap @foo
}
}
Though "bar" is not a valid verdict (should be "jump bar" or something),
the string is taken as the element value. Then NFTA_DATA_VALUE is sent
to the kernel instead of NFTA_DATA_VERDICT. This would be rejected by
recent kernels. On older ones (e.g. v5.4.x) that don't validate the
type, a warning can be seen when the rule is hit, because of the
corrupted verdict value:
[5120263.467627] WARNING: CPU: 12 PID: 303303 at net/netfilter/nf_tables_core.c:229 nft_do_chain+0x394/0x500 [nf_tables]
Indeed, we don't parse verdicts during evaluation, but only chain names,
which is of type string rather than verdict. For example, "jump $var" is
a verdict while "$var" is a string.
Fixes: c64457cff967 ("src: Allow goto and jump to a variable")
Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Diffstat (limited to 'src/evaluate.c')
| -rw-r--r-- | src/evaluate.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/src/evaluate.c b/src/evaluate.c index 919c38c5..d9c9ca28 100644 --- a/src/evaluate.c +++ b/src/evaluate.c @@ -2575,7 +2575,8 @@ static int stmt_evaluate_verdict(struct eval_ctx *ctx, struct stmt *stmt) if (stmt->expr->verdict != NFT_CONTINUE) stmt->flags |= STMT_F_TERMINAL; if (stmt->expr->chain != NULL) { - if (expr_evaluate(ctx, &stmt->expr->chain) < 0) + if (stmt_evaluate_arg(ctx, stmt, &string_type, 0, 0, + &stmt->expr->chain) < 0) return -1; if (stmt->expr->chain->etype != EXPR_VALUE) { return expr_error(ctx->msgs, stmt->expr->chain, |