From cc003c7ee6094bca65435ca4bdbba8c98a7c859f Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Sun, 9 Jan 2022 17:11:25 +0100 Subject: netfilter: nft_payload: cancel register tracking after payload update The payload expression might mangle the packet, cancel register tracking since any payload data in the registers is stale. Finer grain register tracking cancellation by inspecting the payload base, offset and length on the register is also possible. Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_payload.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) (limited to 'net/netfilter') diff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c index f518bf634997..10f422caa76a 100644 --- a/net/netfilter/nft_payload.c +++ b/net/netfilter/nft_payload.c @@ -798,12 +798,33 @@ nla_put_failure: return -1; } +static bool nft_payload_set_reduce(struct nft_regs_track *track, + const struct nft_expr *expr) +{ + int i; + + for (i = 0; i < NFT_REG32_NUM; i++) { + if (!track->regs[i].selector) + continue; + + if (track->regs[i].selector->ops != &nft_payload_ops && + track->regs[i].selector->ops != &nft_payload_fast_ops) + continue; + + track->regs[i].selector = NULL; + track->regs[i].bitwise = NULL; + } + + return false; +} + static const struct nft_expr_ops nft_payload_set_ops = { .type = &nft_payload_type, .size = NFT_EXPR_SIZE(sizeof(struct nft_payload_set)), .eval = nft_payload_set_eval, .init = nft_payload_set_init, .dump = nft_payload_set_dump, + .reduce = nft_payload_set_reduce, }; static const struct nft_expr_ops * -- cgit v1.2.3-59-g8ed1b