xref: /linux/scripts/coccinelle/misc/badty.cocci (revision 0be3ff0c)
1// SPDX-License-Identifier: GPL-2.0-only
2/// Correct the size argument to alloc functions
3///
4//# This makes an effort to find cases where the argument to sizeof is wrong
5//# in memory allocation functions by checking the type of the allocated memory
6//# when it is a double pointer and ensuring the sizeof argument takes a pointer
7//# to the the memory being allocated. There are false positives in cases the
8//# sizeof argument is not used in constructing the return value. The result
9//# may need some reformatting.
10//
11// Confidence: Moderate
12// Copyright: (C) 2014 Himangi Saraogi.
13// Comments:
14// Options:
15
16virtual patch
17virtual context
18virtual org
19virtual report
20
21//----------------------------------------------------------
22//  For context mode
23//----------------------------------------------------------
24
25@depends on context disable sizeof_type_expr@
26type T;
27T **x;
28@@
29
30  x =
31  <+...sizeof(
32* T
33  )...+>
34
35//----------------------------------------------------------
36//  For patch mode
37//----------------------------------------------------------
38
39@depends on patch disable sizeof_type_expr@
40type T;
41T **x;
42@@
43
44  x =
45  <+...sizeof(
46- T
47+ *x
48  )...+>
49
50//----------------------------------------------------------
51//  For org and report mode
52//----------------------------------------------------------
53
54@r depends on (org || report) disable sizeof_type_expr@
55type T;
56T **x;
57position p;
58@@
59
60  x =
61  <+...sizeof(
62  T@p
63  )...+>
64
65@script:python depends on org@
66p << r.p;
67@@
68
69coccilib.org.print_todo(p[0], "WARNING sizeof argument should be pointer type, not structure type")
70
71@script:python depends on report@
72p << r.p;
73@@
74
75msg="WARNING: Use correct pointer type argument for sizeof"
76coccilib.report.print_report(p[0], msg)
77
78