[PATCH 5.6 175/177] netfilter: conntrack: comparison of unsigned in cthelper confirmation

From: Greg Kroah-Hartman
Date: Mon Jun 01 2020 - 14:18:16 EST


From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>

commit 94945ad2b330207cded0fd8d4abebde43a776dfb upstream.

net/netfilter/nf_conntrack_core.c: In function nf_confirm_cthelper:
net/netfilter/nf_conntrack_core.c:2117:15: warning: comparison of unsigned expression in < 0 is always false [-Wtype-limits]
2117 | if (protoff < 0 || (frag_off & htons(~0x7)) != 0)
| ^

ipv6_skip_exthdr() returns a signed integer.

Reported-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
Fixes: 703acd70f249 ("netfilter: nfnetlink_cthelper: unbreak userspace helper support")
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
net/netfilter/nf_conntrack_core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -2090,7 +2090,7 @@ static int nf_confirm_cthelper(struct sk
{
const struct nf_conntrack_helper *helper;
const struct nf_conn_help *help;
- unsigned int protoff;
+ int protoff;

help = nfct_help(ct);
if (!help)