[PATCH] Coccinelle: limit memdup_user transformation to GFP_KERNEL case

From: Julia Lawall
Date: Wed Sep 21 2016 - 12:07:06 EST


Memdup_user encapsulates a memory allocation with the flag GFP_KERNEL, so
only allow this flag in the original code.

Signed-off-by: Julia Lawall <Julia.Lawall@xxxxxxx>

---
scripts/coccinelle/api/memdup_user.cocci | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/scripts/coccinelle/api/memdup_user.cocci b/scripts/coccinelle/api/memdup_user.cocci
index c606231..2a5aea8 100644
--- a/scripts/coccinelle/api/memdup_user.cocci
+++ b/scripts/coccinelle/api/memdup_user.cocci
@@ -15,11 +15,11 @@ virtual org
virtual report

@depends on patch@
-expression from,to,size,flag;
+expression from,to,size;
identifier l1,l2;
@@

-- to = \(kmalloc\|kzalloc\)(size,flag);
+- to = \(kmalloc\|kzalloc\)(size,GFP_KERNEL);
+ to = memdup_user(from,size);
if (
- to==NULL
@@ -37,12 +37,12 @@ identifier l1,l2;
- }

@r depends on !patch@
-expression from,to,size,flag;
+expression from,to,size;
position p;
statement S1,S2;
@@

-* to = \(kmalloc@p\|kzalloc@p\)(size,flag);
+* to = \(kmalloc@p\|kzalloc@p\)(size,GFP_KERNEL);
if (to==NULL || ...) S1
if (copy_from_user(to, from, size) != 0)
S2