1/// NULL check before some freeing functions is not needed.
2///
3/// Based on checkpatch warning
4/// "kfree(NULL) is safe this check is probably not required"
5/// and kfreeaddr.cocci by Julia Lawall.
6///
7// Copyright: (C) 2014 Fabian Frederick.  GPLv2.
8// Comments: -
9// Options: --no-includes --include-headers
10
11virtual patch
12virtual org
13virtual report
14virtual context
15
16@r2 depends on patch@
17expression E;
18@@
19- if (E != NULL)
20(
21  kfree(E);
22|
23  kzfree(E);
24|
25  debugfs_remove(E);
26|
27  debugfs_remove_recursive(E);
28|
29  usb_free_urb(E);
30|
31  kmem_cache_destroy(E);
32|
33  mempool_destroy(E);
34|
35  dma_pool_destroy(E);
36)
37
38@r depends on context || report || org @
39expression E;
40position p;
41@@
42
43* if (E != NULL)
44*	\(kfree@p\|kzfree@p\|debugfs_remove@p\|debugfs_remove_recursive@p\|
45*         usb_free_urb@p\|kmem_cache_destroy@p\|mempool_destroy@p\|
46*         dma_pool_destroy@p\)(E);
47
48@script:python depends on org@
49p << r.p;
50@@
51
52cocci.print_main("NULL check before that freeing function is not needed", p)
53
54@script:python depends on report@
55p << r.p;
56@@
57
58msg = "WARNING: NULL check before freeing functions like kfree, debugfs_remove, debugfs_remove_recursive or usb_free_urb is not needed. Maybe consider reorganizing relevant code to avoid passing NULL values."
59coccilib.report.print_report(p[0], msg)
60