1 files changed, 4 insertions, 1 deletions

diff --git a/net/netfilter/nf_conntrack_sip.c b/net/netfilter/nf_conntrack_sip.c
index 621b81c7bddc..c3fc14e021ec 100644
--- a/net/netfilter/nf_conntrack_sip.c
+++ b/net/netfilter/nf_conntrack_sip.c
@@ -1436,9 +1436,12 @@ static int process_sip_request(struct sk_buff *skb, unsigned int protoff,
                 handler = &sip_handlers[i];
                 if (handler->request == NULL)
                         continue;
-                if (*datalen < handler->len ||
+                if (*datalen < handler->len + 2 ||
                     strncasecmp(*dptr, handler->method, handler->len))
                         continue;
+                if ((*dptr)[handler->len] != ' ' ||
+                    !isalpha((*dptr)[handler->len+1]))
+                        continue;
 
                 if (ct_sip_get_header(ct, *dptr, 0, *datalen, SIP_HDR_CSEQ,
                                       &matchoff, &matchlen) <= 0) {