1// SPDX-License-Identifier: GPL-2.0-only
2/// Remove casting the values returned by memory allocation functions
3/// like kmalloc, kzalloc, kmem_cache_alloc, kmem_cache_zalloc etc.
4///
5//# This makes an effort to find cases of casting of values returned by
6//# kmalloc, kzalloc, kcalloc, kmem_cache_alloc, kmem_cache_zalloc,
7//# kmem_cache_alloc_node, kmalloc_node and kzalloc_node and removes
8//# the casting as it is not required. The result in the patch case may
9//# need some reformatting.
10//
11// Confidence: High
12// Copyright: (C) 2014 Himangi Saraogi
13// Copyright: (C) 2017 Himanshu Jha
14// Comments:
15// Options: --no-includes --include-headers
16//
17
18virtual context
19virtual patch
20virtual org
21virtual report
22
23@initialize:python@
24@@
25import re
26pattern = '__'
27m = re.compile(pattern)
28
29@r1 depends on context || patch@
30type T;
31@@
32
33  (T *)
34  \(kmalloc\|kzalloc\|kcalloc\|kmem_cache_alloc\|kmem_cache_zalloc\|
35   kmem_cache_alloc_node\|kmalloc_node\|kzalloc_node\|vmalloc\|vzalloc\|
36   dma_alloc_coherent\|devm_kmalloc\|devm_kzalloc\|
37   kvmalloc\|kvzalloc\|kvmalloc_node\|kvzalloc_node\|pci_alloc_consistent\|
38   pci_zalloc_consistent\|kmem_alloc\|kmem_zalloc\|kmem_zone_alloc\|
39   kmem_zone_zalloc\|vmalloc_node\|vzalloc_node\)(...)
40
41//----------------------------------------------------------
42//  For context mode
43//----------------------------------------------------------
44
45@script:python depends on context@
46t << r1.T;
47@@
48
49if m.search(t) != None:
50        cocci.include_match(False)
51
52@depends on context && r1@
53type r1.T;
54@@
55
56* (T *)
57  \(kmalloc\|kzalloc\|kcalloc\|kmem_cache_alloc\|kmem_cache_zalloc\|
58   kmem_cache_alloc_node\|kmalloc_node\|kzalloc_node\|vmalloc\|vzalloc\|
59   dma_alloc_coherent\|devm_kmalloc\|devm_kzalloc\|
60   kvmalloc\|kvzalloc\|kvmalloc_node\|kvzalloc_node\|pci_alloc_consistent\|
61   pci_zalloc_consistent\|kmem_alloc\|kmem_zalloc\|kmem_zone_alloc\|
62   kmem_zone_zalloc\|vmalloc_node\|vzalloc_node\)(...)
63
64//----------------------------------------------------------
65//  For patch mode
66//----------------------------------------------------------
67
68@script:python depends on patch@
69t << r1.T;
70@@
71
72if m.search(t) != None:
73        cocci.include_match(False)
74
75@depends on patch && r1@
76type r1.T;
77@@
78
79- (T *)
80  \(kmalloc\|kzalloc\|kcalloc\|kmem_cache_alloc\|kmem_cache_zalloc\|
81   kmem_cache_alloc_node\|kmalloc_node\|kzalloc_node\|vmalloc\|vzalloc\|
82   dma_alloc_coherent\|devm_kmalloc\|devm_kzalloc\|
83   kvmalloc\|kvzalloc\|kvmalloc_node\|kvzalloc_node\|pci_alloc_consistent\|
84   pci_zalloc_consistent\|kmem_alloc\|kmem_zalloc\|kmem_zone_alloc\|
85   kmem_zone_zalloc\|vmalloc_node\|vzalloc_node\)(...)
86
87//----------------------------------------------------------
88//  For org and report mode
89//----------------------------------------------------------
90
91@r2 depends on org || report@
92type T;
93position p;
94@@
95
96 (T@p *)
97  \(kmalloc\|kzalloc\|kcalloc\|kmem_cache_alloc\|kmem_cache_zalloc\|
98   kmem_cache_alloc_node\|kmalloc_node\|kzalloc_node\|vmalloc\|vzalloc\|
99   dma_alloc_coherent\|devm_kmalloc\|devm_kzalloc\|
100   kvmalloc\|kvzalloc\|kvmalloc_node\|kvzalloc_node\|pci_alloc_consistent\|
101   pci_zalloc_consistent\|kmem_alloc\|kmem_zalloc\|kmem_zone_alloc\|
102   kmem_zone_zalloc\|vmalloc_node\|vzalloc_node\)(...)
103
104@script:python depends on org@
105p << r2.p;
106t << r2.T;
107@@
108
109if m.search(t) != None:
110	cocci.include_match(False)
111else:
112	coccilib.org.print_safe_todo(p[0], t)
113
114@script:python depends on report@
115p << r2.p;
116t << r2.T;
117@@
118
119if m.search(t) != None:
120	cocci.include_match(False)
121else:
122	msg="WARNING: casting value returned by memory allocation function to (%s *) is useless." % (t)
123	coccilib.report.print_report(p[0], msg)
124