diff --git a/.changes/fix-cmd-spawn-deadlock.md b/.changes/fix-cmd-spawn-deadlock.md
new file mode 100644
index 00000000..0e2e6870
--- /dev/null
+++ b/.changes/fix-cmd-spawn-deadlock.md
@@ -0,0 +1,5 @@
+---
+"shell": patch
+---
+
+Fixes a deadlock when reading a stdout or stderr line returns an error.
diff --git a/plugins/shell/src/process/mod.rs b/plugins/shell/src/process/mod.rs
index b797be7e..fdb26897 100644
--- a/plugins/shell/src/process/mod.rs
+++ b/plugins/shell/src/process/mod.rs
@@ -385,6 +385,7 @@ fn spawn_pipe_reader<F: Fn(Vec<u8>) -> CommandEvent + Send + Copy + 'static>(
                         block_on_task(
                             async move { tx_.send(CommandEvent::Error(e.to_string())).await },
                         );
+                    break;
                 }
             }
         }