Fix possible crash due to unsigned int number wrapping

1 files changed, 6 insertions, 6 deletions

diff --git a/src/lib/protocols/tls.c b/src/lib/protocols/tls.c
index c65d4fc69..9d22a66db 100644
--- a/src/lib/protocols/tls.c
+++ b/src/lib/protocols/tls.c
@@ -764,7 +764,12 @@ int getSSCertificateFingerprint(struct ndpi_detection_module_struct *ndpi_struct
     return(1); /* More packets please */
   else if(flow->l4.tcp.tls_srv_cert_fingerprint_processed)
     return(0); /* We're good */
-  
+
+  if(packet->payload_packet_len <= flow->l4.tcp.tls_record_offset) {
+    /* Avoid invalid memory accesses */
+    return(1);
+  }
+
   if(flow->l4.tcp.tls_fingerprint_len > 0) {
     unsigned int avail = packet->payload_packet_len - flow->l4.tcp.tls_record_offset;
 
@@ -817,11 +822,6 @@ int getSSCertificateFingerprint(struct ndpi_detection_module_struct *ndpi_struct
     }
   }
 
-  if(packet->payload_packet_len <= flow->l4.tcp.tls_record_offset) {
-    /* Avoid invalid memory accesses */
-    return(1);
-  }
-
   if(packet->payload[flow->l4.tcp.tls_record_offset] == 0x15 /* Alert */) {
     u_int len = ntohs(*(u_int16_t*)&packet->payload[flow->l4.tcp.tls_record_offset+3]) + 5 /* SSL header len */;