From 473e49252e52dbbe053b330632c87f916f37876b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Damir=20Jeli=C4=87?= <poljar@termina.org.uk>
Date: Thu, 8 Oct 2020 15:56:17 +0200
Subject: [PATCH] crytpo: Get the session from the list of sessions in a safe
 manner.

---
 matrix_sdk_crypto/src/identities/device.rs | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/matrix_sdk_crypto/src/identities/device.rs b/matrix_sdk_crypto/src/identities/device.rs
index 8ab5f2ca..73aeb22d 100644
--- a/matrix_sdk_crypto/src/identities/device.rs
+++ b/matrix_sdk_crypto/src/identities/device.rs
@@ -365,9 +365,15 @@ impl ReadOnlyDevice {
             return Err(EventError::MissingSenderKey.into());
         };
 
-        let mut session = if let Some(s) = store.get_sessions(sender_key).await? {
-            let session = &s.lock().await[0];
-            session.clone()
+        let session = if let Some(s) = store.get_sessions(sender_key).await? {
+            let sessions = s.lock().await;
+            sessions.get(0).cloned()
+        } else {
+            None
+        };
+
+        let mut session = if let Some(s) = session {
+            s
         } else {
             warn!(
                 "Trying to encrypt a Megolm session for user {} on device {}, \