[PATCH] scripts/coccinelle: Catch dubious code after &error_abort/&error_fatal

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

Calls passing &error_abort or &error_fatal don't return.
Any code after such use is dubious. Add a coccinelle patch
to detect such pattern.

Inspired-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 .../use-after-abort-fatal-errp.cocci          | 33 +++++++++++++++++++
 MAINTAINERS                                   |  1 +
 2 files changed, 34 insertions(+)
 create mode 100644 scripts/coccinelle/use-after-abort-fatal-errp.cocci

diff --git a/scripts/coccinelle/use-after-abort-fatal-errp.cocci b/scripts/coccinelle/use-after-abort-fatal-errp.cocci
new file mode 100644
index 00000000000..ead9de5826a
--- /dev/null
+++ b/scripts/coccinelle/use-after-abort-fatal-errp.cocci
@@ -0,0 +1,33 @@
+/* Find dubious code use after error_abort/error_fatal
+ *
+ * Inspired by this patch:
+ * https://www.mail-archive.com/qemu-devel@nongnu.org/msg789501.html
+ *
+ * Copyright (C) 2121 Red Hat, Inc.
+ *
+ * Authors:
+ *  Philippe Mathieu-Daudé
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+@@
+identifier func_with_errp;
+@@
+(
+ if (func_with_errp(..., &error_fatal)) {
+    /* Used for displaying help message */
+    ...
+    exit(...);
+  }
+|
+*if (func_with_errp(..., &error_fatal)) {
+    /* dubious code */
+    ...
+  }
+|
+*if (func_with_errp(..., &error_abort)) {
+    /* dubious code */
+    ...
+  }
+)
diff --git a/MAINTAINERS b/MAINTAINERS
index 1e15dab8cd4..db6596eb06d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2368,6 +2368,7 @@ F: scripts/coccinelle/error_propagate_null.cocci
 F: scripts/coccinelle/remove_local_err.cocci
 F: scripts/coccinelle/use-error_fatal.cocci
 F: scripts/coccinelle/errp-guard.cocci
+F: scripts/coccinelle/use-after-abort-fatal-errp.cocci
 
 GDB stub
 M: Alex Bennée <alex.bennee@linaro.org>
-- 
2.26.2