[NETFILTER]: Fix return value confusion in PPTP NAT helper

ip_nat_mangle_tcp_packet doesn't return NF_* values but 0/1 for
failure/success.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 13 insertions, 23 deletions

diff --git a/net/ipv4/netfilter/ip_nat_helper_pptp.c b/net/ipv4/netfilter/ip_nat_helper_pptp.c
index 50960cb681f8..ac004895781a 100644
--- a/net/ipv4/netfilter/ip_nat_helper_pptp.c
+++ b/net/ipv4/netfilter/ip_nat_helper_pptp.c
@@ -299,8 +299,6 @@ pptp_inbound_pkt(struct sk_buff **pskb,
         u_int16_t msg, new_cid = 0, new_pcid;
         unsigned int pcid_off, cid_off = 0;
 
-        int ret = NF_ACCEPT, rv;
-
         new_pcid = htons(nat_pptp_info->pns_call_id);
 
         switch (msg = ntohs(ctlh->messageType)) {
@@ -345,32 +343,24 @@ pptp_inbound_pkt(struct sk_buff **pskb,
         /* mangle packet */
         DEBUGP("altering peer call id from 0x%04x to 0x%04x\n",
                 ntohs(*(u_int16_t *)pptpReq + pcid_off), ntohs(new_pcid));
-        
-        rv = ip_nat_mangle_tcp_packet(pskb, ct, ctinfo,
-                                      pcid_off + sizeof(struct pptp_pkt_hdr) +
-                                      sizeof(struct PptpControlHeader),
-                                      sizeof(new_pcid), (char *)&new_pcid, 
-                                      sizeof(new_pcid));
-        if (rv != NF_ACCEPT) 
-                return rv;
+
+        if (ip_nat_mangle_tcp_packet(pskb, ct, ctinfo,
+                                     pcid_off + sizeof(struct pptp_pkt_hdr) +
+                                     sizeof(struct PptpControlHeader),
+                                     sizeof(new_pcid), (char *)&new_pcid,
+                                     sizeof(new_pcid)) == 0)
+                return NF_DROP;
 
         if (new_cid) {
                 DEBUGP("altering call id from 0x%04x to 0x%04x\n",
                         ntohs(*(u_int16_t *)pptpReq + cid_off), ntohs(new_cid));
-                rv = ip_nat_mangle_tcp_packet(pskb, ct, ctinfo,
-                                              cid_off + sizeof(struct pptp_pkt_hdr) +
-                                              sizeof(struct PptpControlHeader),
-                                              sizeof(new_cid), (char *)&new_cid, 
-                                              sizeof(new_cid));
-                if (rv != NF_ACCEPT)
-                        return rv;
+                if (ip_nat_mangle_tcp_packet(pskb, ct, ctinfo,
+                                             cid_off + sizeof(struct pptp_pkt_hdr) +
+                                             sizeof(struct PptpControlHeader),
+                                             sizeof(new_cid), (char *)&new_cid,
+                                             sizeof(new_cid)) == 0)
+                        return NF_DROP;
         }
-
-        /* check for earlier return value of 'switch' above */
-        if (ret != NF_ACCEPT)
-                return ret;
-
-        /* great, at least we don't need to resize packets */
         return NF_ACCEPT;
 }