[PATCH] kernelshark: make sure ksmodels index is valid before use

Pressing Ctrl+C with no data loaded will lead to a crash.
Steps to reproduce:
Click in the trace viewer window.
Press Ctrl+C.

Signed-off-by: Mircea Cirjaliu <[email protected]>
---
 src/KsModels.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/KsModels.cpp b/src/KsModels.cpp
index c8a6ba3..cf4cfe9 100644
--- a/src/KsModels.cpp
+++ b/src/KsModels.cpp
@@ -309,7 +309,8 @@ QVariant KsViewModel::data(const QModelIndex &index, int role) const
 	}
 
 	if (role == Qt::DisplayRole)
-		return this->getValue(index.column(), index.row());
+		if (index.isValid())
+			return this->getValue(index.column(), index.row());
 
 	return {};
 }
-- 
2.43.0