| Message ID | 20231105174148.160390-1-pablo@netfilter.org |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | [nft] evaluate: reset statement length context only for set mappings | expand |
diff --git a/src/evaluate.c b/src/evaluate.c index 894987df7895..65e4cef9c147 100644 --- a/src/evaluate.c +++ b/src/evaluate.c @@ -1918,13 +1918,13 @@ static int expr_evaluate_map(struct eval_ctx *ctx, struct expr **expr) } expr_set_context(&ctx->ectx, NULL, 0); - ctx->stmt_len = 0; if (expr_evaluate(ctx, &map->map) < 0) return -1; if (expr_is_constant(map->map)) return expr_error(ctx->msgs, map->map, "Map expression can not be constant"); + ctx->stmt_len = 0; mappings = map->mappings; mappings->set_flags |= NFT_SET_MAP;
map expression needs to consider the statement length context, otherwise incorrect bytecode is generated when {ct,meta} statement is generated. # nft -f - <<EOF add table ip6 t add chain ip6 t c add map ip6 t mapv6 { typeof ip6 dscp : meta mark; } EOF # nft -d netlink add rule ip6 t c meta mark set ip6 dscp map @mapv6 ip6 t c [ payload load 2b @ network header + 0 => reg 1 ] [ bitwise reg 1 = ( reg 1 & 0x0000c00f ) ^ 0x00000000 ] ... missing byteorder conversion here before shift ... [ bitwise reg 1 = ( reg 1 >> 0x00000006 ) ] [ lookup reg 1 set mapv6 dreg 1 ] [ meta set mark with reg 1 ] Reset statement length context only for the mapping side for the elements in the set. Fixes: edecd58755a8 ("evaluate: support shifts larger than the width of the left operand") Reported-by: Brian Davidson <davidson.brian@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> --- Missing tests/py, I will add it in a v2 for this patch. src/evaluate.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)