Subject: [PATCH v2 02/19] coccicheck: detect hashmap_entry.hash assignment

From: Eric Wong <[email-masked]>
Date: Tue, 24 Sep 2019 01:03:07 +0000

Assigning hashmap_entry.hash manually leaves hashmap_entry.next
uninitialized, which can be dangerous once the hashmap_entry is
inserted into a hashmap.   Detect those assignments and use
hashmap_entry_init, instead.

Signed-off-by: Eric Wong <[email-masked]>
---
 contrib/coccinelle/hashmap.cocci | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)
 create mode 100644 contrib/coccinelle/hashmap.cocci

diff --git a/contrib/coccinelle/hashmap.cocci b/contrib/coccinelle/hashmap.cocci
new file mode 100644
index 0000000000..d69e120ccf
--- /dev/null
+++ b/contrib/coccinelle/hashmap.cocci
@@ -0,0 +1,16 @@
+@ hashmap_entry_init_usage @
+expression E;
+struct hashmap_entry HME;
+@@
+- HME.hash = E;
++ hashmap_entry_init(&HME, E);
+
+@@
+identifier f !~ "^hashmap_entry_init$";
+expression E;
+struct hashmap_entry *HMEP;
+@@
+  f(...) {<...
+- HMEP->hash = E;
++ hashmap_entry_init(HMEP, E);
+  ...>}