@@ -128,7 +128,7 @@ static const struct nla_policy nft_rule_compat_policy[NFTA_RULE_COMPAT_MAX + 1]
[NFTA_RULE_COMPAT_FLAGS] = { .type = NLA_U32 },
};
-static u8 nft_parse_compat(const struct nlattr *attr, bool *inv)
+static int nft_parse_compat(const struct nlattr *attr, u8 *proto, bool *inv)
{
struct nlattr *tb[NFTA_RULE_COMPAT_MAX+1];
u32 flags;
@@ -148,7 +148,8 @@ static u8 nft_parse_compat(const struct nlattr *attr, bool *inv)
if (flags & NFT_RULE_COMPAT_F_INV)
*inv = true;
- return ntohl(nla_get_be32(tb[NFTA_RULE_COMPAT_PROTO]));
+ *proto = ntohl(nla_get_be32(tb[NFTA_RULE_COMPAT_PROTO]));
+ return 0;
}
static int
@@ -166,8 +167,11 @@ nft_target_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
target_compat_from_user(target, nla_data(tb[NFTA_TARGET_INFO]), info);
- if (ctx->nla[NFTA_RULE_COMPAT])
- proto = nft_parse_compat(ctx->nla[NFTA_RULE_COMPAT], &inv);
+ if (ctx->nla[NFTA_RULE_COMPAT]) {
+ ret = nft_parse_compat(ctx->nla[NFTA_RULE_COMPAT], &proto, &inv);
+ if (ret < 0)
+ goto err;
+ }
nft_target_set_tgchk_param(&par, ctx, target, info, &e, proto, inv);
@@ -356,8 +360,11 @@ nft_match_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
match_compat_from_user(match, nla_data(tb[NFTA_MATCH_INFO]), info);
- if (ctx->nla[NFTA_RULE_COMPAT])
- proto = nft_parse_compat(ctx->nla[NFTA_RULE_COMPAT], &inv);
+ if (ctx->nla[NFTA_RULE_COMPAT]) {
+ ret = nft_parse_compat(ctx->nla[NFTA_RULE_COMPAT], &proto, &inv);
+ if (ret < 0)
+ goto err;
+ }
nft_match_set_mtchk_param(&par, ctx, match, info, &e, proto, inv);
The patch 0ca743a55991: "netfilter: nf_tables: add compatibility layer for x_tables", leads to the following Smatch warning: "net/netfilter/nft_compat.c:140 nft_parse_compat() warn: signedness bug returning '(-34)'" This nft_parse_compat function returns error codes but the return type is u8 so the error codes are transformed into small positive values. The callers don't check the return. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> --- net/netfilter/nft_compat.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-)