From 952bf8df222599baadbd4f838a49c4fef81d2564 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Wed, 26 Jun 2024 23:15:38 +0200 Subject: [PATCH] netfilter: nf_tables: fully validate NFT_DATA_VALUE on store to data registers [ Upstream commit 7931d32955e09d0a11b1fe0b6aac1bfa061c005c ] register store validation for NFT_DATA_VALUE is conditional, however, the datatype is always either NFT_DATA_VALUE or NFT_DATA_VERDICT. This only requires a new helper function to infer the register type from the set datatype so this conditional check can be removed. Otherwise, pointer to chain object can be leaked through the registers. Fixes: 96518518cc41 ("netfilter: add nftables") Reported-by: Linus Torvalds Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- include/net/netfilter/nf_tables.h | 5 +++++ net/netfilter/nf_tables_api.c | 8 ++++---- net/netfilter/nft_lookup.c | 3 ++- 3 files changed, 11 insertions(+), 5 deletions(-) diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h index 5bb8a83e2604..8af2543520b9 100644 --- a/include/net/netfilter/nf_tables.h +++ b/include/net/netfilter/nf_tables.h @@ -587,6 +587,11 @@ static inline void *nft_set_priv(const struct nft_set *set) return (void *)set->data; } +static inline enum nft_data_types nft_set_datatype(const struct nft_set *set) +{ + return set->dtype == NFT_DATA_VERDICT ? NFT_DATA_VERDICT : NFT_DATA_VALUE; +} + static inline bool nft_set_gc_is_pending(const struct nft_set *s) { return refcount_read(&s->refs) != 1; diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 387eee416b0b..7547f7b86939 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -5648,8 +5648,7 @@ static int nf_tables_fill_setelem(struct sk_buff *skb, if (nft_set_ext_exists(ext, NFT_SET_EXT_DATA) && nft_data_dump(skb, NFTA_SET_ELEM_DATA, nft_set_ext_data(ext), - set->dtype == NFT_DATA_VERDICT ? NFT_DATA_VERDICT : NFT_DATA_VALUE, - set->dlen) < 0) + nft_set_datatype(set), set->dlen) < 0) goto nla_put_failure; if (nft_set_ext_exists(ext, NFT_SET_EXT_EXPRESSIONS) && @@ -10881,6 +10880,9 @@ static int nft_validate_register_store(const struct nft_ctx *ctx, return 0; default: + if (type != NFT_DATA_VALUE) + return -EINVAL; + if (reg < NFT_REG_1 * NFT_REG_SIZE / NFT_REG32_SIZE) return -EINVAL; if (len == 0) @@ -10889,8 +10891,6 @@ static int nft_validate_register_store(const struct nft_ctx *ctx, sizeof_field(struct nft_regs, data)) return -ERANGE; - if (data != NULL && type != NFT_DATA_VALUE) - return -EINVAL; return 0; } } diff --git a/net/netfilter/nft_lookup.c b/net/netfilter/nft_lookup.c index 870e5b113d13..7ba4b1454db4 100644 --- a/net/netfilter/nft_lookup.c +++ b/net/netfilter/nft_lookup.c @@ -132,7 +132,8 @@ static int nft_lookup_init(const struct nft_ctx *ctx, return -EINVAL; err = nft_parse_register_store(ctx, tb[NFTA_LOOKUP_DREG], - &priv->dreg, NULL, set->dtype, + &priv->dreg, NULL, + nft_set_datatype(set), set->dlen); if (err < 0) return err;