Avoid crash in ARRTRIM (fix issue RedisJSON#485) (RedisJSON#499)

oshadmi · web-flow · commit dde2450b4870 · 2021-10-31T20:52:45.000+02:00
diff --git a/src/manager.rs b/src/manager.rs
@@ -439,11 +439,15 @@ impl<'a> WriteHolder<Value, Value> for KeyHolderWrite<'a> {
             if let Some(array) = v.as_array() {
                 let len = array.len() as i64;
                 let stop = stop.normalize(len);
-
-                let range = if start > len || start > stop as i64 || len == 0 {
+                let start = if start < 0 || start < len {
+                    start.normalize(len)
+                } else {
+                    stop + 1 //  start >=0 && start >= len
+                };
+                let range = if start > stop || len == 0 {
                     0..0 // Return an empty array
                 } else {
-                    start.normalize(len)..(stop + 1)
+                    start..(stop + 1)
                 };
 
                 let mut new_value = v.take();
diff --git a/tests/pytest/test.py b/tests/pytest/test.py
@@ -674,6 +674,14 @@ def testArrTrimCommand(env):
 
     r.assertEqual(r.execute_command('JSON.ARRTRIM', 'test', '.arr', -1, 0), 0)
 
+    r.assertOk(r.execute_command('JSON.SET', 'test',
+                                 '.', '{ "arr": [0, 1, 2, 3, 2, 1, 0] }'))
+    r.assertEqual(r.execute_command('JSON.ARRTRIM', 'test', '.arr', -1, 0), 0)
+
+    r.assertOk(r.execute_command('JSON.SET', 'test',
+                                 '.', '{ "arr": [0, 1, 2, 3, 2, 1, 0] }'))
+    r.assertEqual(r.execute_command('JSON.ARRTRIM', 'test', '.arr', -4, 1), 0)
+
 
 def testArrPopCommand(env):
     """Test JSON.ARRPOP command"""
