[PATCH v3 02/20] coccicheck: detect hashmap_entry.hash assignment

From: Eric Wong <e@80x24.org>
Date: Oct 6, 2019, 23:30 UTC
Message-ID: <20191006233043.3516-3-e@80x24.org>
In-Reply-To: <20191006233043.3516-1-e@80x24.org>

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 <e@80x24.org>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
---
 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);
+  ...>}