diff --git a/include/proto/stream.h b/include/proto/stream.h
index f448209..a8c2992 100644
--- a/include/proto/stream.h
+++ b/include/proto/stream.h
@@ -103,7 +103,8 @@
 		if (ptr) {
 			HA_RWLOCK_WRLOCK(STK_SESS_LOCK, &ts->lock);
 
-			stktable_data_cast(ptr, conn_cur)--;
+			if (stktable_data_cast(ptr, conn_cur) > 0)
+				stktable_data_cast(ptr, conn_cur)--;
 
 			HA_RWLOCK_WRUNLOCK(STK_SESS_LOCK, &ts->lock);
 
@@ -141,7 +142,8 @@
 		if (ptr) {
 			HA_RWLOCK_WRLOCK(STK_SESS_LOCK, &ts->lock);
 
-			stktable_data_cast(ptr, conn_cur)--;
+			if (stktable_data_cast(ptr, conn_cur) > 0)
+				stktable_data_cast(ptr, conn_cur)--;
 
 			HA_RWLOCK_WRUNLOCK(STK_SESS_LOCK, &ts->lock);