netfilter: nft_payload: report ERANGE for too long offset and length

[ Upstream commit 94254f990c07e9ddf1634e0b727fab821c3b5bf9 ]

Instead of offset and length are truncation to u8, report ERANGE.

Fixes: 96518518cc41 ("netfilter: add nftables")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c
index f73d47b3ffb72d73845d14f253ea6a6c76f55dd4..82bcd14fbcb3dffb7583cbcac8780761205b1239 100644 (file)
--- a/net/netfilter/nft_payload.c
+++ b/net/netfilter/nft_payload.c
@@ -287,6 +287,7 @@ nft_payload_select_ops(const struct nft_ctx *ctx,
 {
        enum nft_payload_bases base;
        unsigned int offset, len;
+       int err;
 
        if (tb[NFTA_PAYLOAD_BASE] == NULL ||
            tb[NFTA_PAYLOAD_OFFSET] == NULL ||
@@ -312,8 +313,13 @@ nft_payload_select_ops(const struct nft_ctx *ctx,
        if (tb[NFTA_PAYLOAD_DREG] == NULL)
                return ERR_PTR(-EINVAL);
 
-       offset = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_OFFSET]));
-       len    = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_LEN]));
+       err = nft_parse_u32_check(tb[NFTA_PAYLOAD_OFFSET], U8_MAX, &offset);
+       if (err < 0)
+               return ERR_PTR(err);
+
+       err = nft_parse_u32_check(tb[NFTA_PAYLOAD_LEN], U8_MAX, &len);
+       if (err < 0)
+               return ERR_PTR(err);
 
        if (len <= 4 && is_power_of_2(len) && IS_ALIGNED(offset, len) &&
            base != NFT_PAYLOAD_LL_HEADER)