| Message ID | 20191224231211.1972101-1-jeremy@azazel.net |
|---|---|
| State | Superseded |
| Delegated to: | Pablo Neira |
| Headers | show |
| Series | [nftables] evaluate: remove expr_set_context call. | expand |
On 2019-12-24, at 23:12:11 +0000, Jeremy Sowden wrote: > expr_evaluate_binop calls expr_set_context for shift expressions to > set the context data-type to `integer`. This doesn't seem to serve a > purpose, and its only effect is to clobber the byte-order of the > context, resulting in unexpected conversions to NBO. For example: Whoops. Sent v1 again, instead of v2. Let's try that again. J.
diff --git a/src/evaluate.c b/src/evaluate.c index a865902c0fc7..0feb7d484405 100644 --- a/src/evaluate.c +++ b/src/evaluate.c @@ -1144,8 +1144,6 @@ static int expr_evaluate_binop(struct eval_ctx *ctx, struct expr **expr) return -1; left = op->left; - if (op->op == OP_LSHIFT || op->op == OP_RSHIFT) - expr_set_context(&ctx->ectx, &integer_type, ctx->ectx.len); if (expr_evaluate(ctx, &op->right) < 0) return -1; right = op->right;
expr_evaluate_binop calls expr_set_context for shift expressions to set the context data-type to `integer`. This doesn't seem to serve a purpose, and its only effect is to clobber the byte-order of the context, resulting in unexpected conversions to NBO. For example: $ sudo nft flush ruleset $ sudo nft add table t $ sudo nft add chain t c '{ type filter hook output priority mangle; }' $ sudo nft add rule t c oif lo tcp dport ssh ct mark set '0x10 | 0xe' $ sudo nft add rule t c oif lo tcp dport ssh ct mark set '0xf << 1' $ sudo nft list table t table ip t { chain c { type filter hook output priority mangle; policy accept; oif "lo" tcp dport 22 ct mark set 0x0000001e oif "lo" tcp dport 22 ct mark set 0x1e000000 } } Signed-off-by: Jeremy Sowden <jeremy@azazel.net> --- src/evaluate.c | 2 -- 1 file changed, 2 deletions(-)