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
135
136
137
138
139
140
141
142
143
144
145
|
# 2009 June 3
#
# The author disclaims copyright to this source code. In place of
# a legal notice, here is a blessing:
#
# May you do good and not evil.
# May you find forgiveness for yourself and forgive others.
# May you share freely, never taking more than you give.
#
#***********************************************************************
#
# $Id: corruptD.test,v 1.2 2009/06/05 17:09:12 drh Exp $
set testdir [file dirname $argv0]
source $testdir/tester.tcl
# Do not use a codec for tests in this file, as the database file is
# manipulated directly using tcl scripts (using the [hexio_write] command).
#
do_not_use_codec
# These tests deal with corrupt database files
#
database_may_be_corrupt
#--------------------------------------------------------------------------
# OVERVIEW
#
# This test file attempts to verify that SQLite does not read past the
# end of any in-memory buffers as a result of corrupted database page
# images. Usually this happens because a field within a database page
# that contains an offset to some other structure within the same page
# is set to too large a value. A database page contains the following
# such fields:
#
# 1. The page header field that contains the offset to the first
# free block of space.
#
# 2. The first two bytes of all but the last free block on the free-block
# list (the offset to the next free block).
#
# 3. The page header field containing the number of cells on the page
# (implicitly defines the offset to the final element in the cell offset
# array, which could potentially be off the end of the page).
#
# 4. The page header field containing the offset to the start of the cell
# content area.
#
# 5. The contents of the cell offset array.
#
# 6. The first few bytes of each cell determine the size of the cell
# stored within the page, and hence the offset to the final byte of
# the cell.
#
# If any of the above fields are set to too large a value, then a buffer
# overread may occur. This test script creates and operates on various
# strategically corrupted database files to attempt to provoke such buffer
# overreads.
#
# Very often, a buffer overread passes unnoticed, particularly in workstation
# environments. For this reason, this test script should be run using valgrind
# (or similar) in order to verify that no overreads occur.
#
# TEST PLAN
#
# Test cases corruptD-1.* are white-box tests. They attempt to corrupt
# one of the above fields, then exercise each part of the code in btree.c
# that uses said field.
#
# Offset variables 1, 2, 3 and 4 are all checked to make sure they
# will not result in buffer overruns as part of page initialization in
# sqlite3BtreeInitPage(). Offsets 5 and 6 cannot be tested as part of
# page initialization, as trying to do so causes a performance hit.
#
do_test corruptD-1.0 {
execsql {
PRAGMA auto_vacuum = 0;
PRAGMA page_size = 1024;
CREATE TABLE t1(a, b);
CREATE INDEX i1 ON t1(a, b);
}
for {set ii 1} {$ii < 50} {incr ii} {
execsql { INSERT INTO t1 VALUES($ii, $ii * $ii) }
}
execsql {
DELETE FROM t1 WHERE a = 10;
DELETE FROM t1 WHERE a = 20;
DELETE FROM t1 WHERE a = 30;
DELETE FROM t1 WHERE a = 40;
}
forcecopy test.db test.bu
} {}
proc incr_change_counter {} {
hexio_write test.db 24 [
hexio_render_int32 [expr [hexio_get_int [hexio_read test.db 24 4]] + 1]
]
}
proc restore_file {} {
db close
forcecopy test.bu test.db
sqlite3 db test.db
}
#-------------------------------------------------------------------------
# The following tests, corruptD-1.1.*, focus on the page header field
# containing the offset of the first free block in a page.
#
do_test corruptD-1.1.1 {
incr_change_counter
hexio_write test.db [expr 1024+1] FFFF
catchsql { PRAGMA quick_check }
} {0 {{*** in database main ***
Tree 2 page 2: free space corruption}}}
do_test corruptD-1.1.2 {
incr_change_counter
hexio_write test.db [expr 1024+1] [hexio_render_int32 1021]
catchsql { SELECT * FROM t1 ORDER BY rowid }
} {1 {database disk image is malformed}}
#-------------------------------------------------------------------------
# The following tests, corruptD-1.2.*, focus on the offsets contained
# in the first 2 byte of each free-block on the free-list.
#
do_test corruptD-1.2.1 {
restore_file
} {}
do_test corruptD-1.2.2 {
} {}
#-------------------------------------------------------------------------
# The following tests, corruptD-1.4.*, ...
#
#-------------------------------------------------------------------------
# The following tests, corruptD-1.5.*, focus on the offsets contained
# in the cell offset array.
#
# defragmentPage
#
finish_test
|
