summaryrefslogtreecommitdiffstats
path: root/scripts/coccinelle/free/kfree.cocci
blob: e9d50e718e465b7afb659bae7f86092a799d3688 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
// SPDX-License-Identifier: GPL-2.0-only
/// Find a use after free.
//# Values of variables may imply that some
//# execution paths are not possible, resulting in false positives.
//# Another source of false positives are macros such as
//# SCTP_DBG_OBJCNT_DEC that do not actually evaluate their argument
///
// Confidence: Moderate
// Copyright: (C) 2010-2012 Nicolas Palix.
// Copyright: (C) 2010-2012 Julia Lawall, INRIA/LIP6.
// Copyright: (C) 2010-2012 Gilles Muller, INRIA/LiP6.
// URL: http://coccinelle.lip6.fr/
// Comments:
// Options: --no-includes --include-headers

virtual org
virtual report

@free@
expression E;
position p1;
@@

(
* kfree@p1(E)
|
* kzfree@p1(E)
)

@print expression@
constant char [] c;
expression free.E,E2;
type T;
position p;
identifier f;
@@

(
 f(...,c,...,(T)E@p,...)
|
 E@p == E2
|
 E@p != E2
|
 E2 == E@p
|
 E2 != E@p
|
 !E@p
|
 E@p || ...
)

@sz@
expression free.E;
position p;
@@

 sizeof(<+...E@p...+>)

@loop exists@
expression E;
identifier l;
position ok;
@@

while (1) { ...
(
* kfree@ok(E)
|
* kzfree@ok(E)
)
  ... when != break;
      when != goto l;
      when forall
}

@r exists@
expression free.E, subE<=free.E, E2;
expression E1;
iterator iter;
statement S;
position free.p1!=loop.ok,p2!={print.p,sz.p};
@@

(
* kfree@p1(E,...)
|
* kzfree@p1(E,...)
)
...
(
 iter(...,subE,...) S // no use
|
 list_remove_head(E1,subE,...)
|
 subE = E2
|
 subE++
|
 ++subE
|
 --subE
|
 subE--
|
 &subE
|
 BUG(...)
|
 BUG_ON(...)
|
 return_VALUE(...)
|
 return_ACPI_STATUS(...)
|
 E@p2 // bad use
)

@script:python depends on org@
p1 << free.p1;
p2 << r.p2;
@@

cocci.print_main("kfree",p1)
cocci.print_secs("ref",p2)

@script:python depends on report@
p1 << free.p1;
p2 << r.p2;
@@

msg = "ERROR: reference preceded by free on line %s" % (p1[0].line)
coccilib.report.print_report(p2[0],msg)