Commit | Line | Data |
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00f496c4 KC |
1 | /* |
2 | * This is for all the tests related to logic bugs (e.g. bad dereferences, | |
3 | * bad alignment, bad loops, bad locking, bad scheduling, deep stacks, and | |
4 | * lockups) along with other things that don't fit well into existing LKDTM | |
5 | * test source files. | |
6 | */ | |
00f496c4 | 7 | #include "lkdtm.h" |
6d2e91a6 | 8 | #include <linux/sched.h> |
00f496c4 KC |
9 | |
10 | /* | |
11 | * Make sure our attempts to over run the kernel stack doesn't trigger | |
12 | * a compiler warning when CONFIG_FRAME_WARN is set. Then make sure we | |
13 | * recurse past the end of THREAD_SIZE by default. | |
14 | */ | |
15 | #if defined(CONFIG_FRAME_WARN) && (CONFIG_FRAME_WARN > 0) | |
16 | #define REC_STACK_SIZE (CONFIG_FRAME_WARN / 2) | |
17 | #else | |
18 | #define REC_STACK_SIZE (THREAD_SIZE / 8) | |
19 | #endif | |
20 | #define REC_NUM_DEFAULT ((THREAD_SIZE / REC_STACK_SIZE) * 2) | |
21 | ||
22 | static int recur_count = REC_NUM_DEFAULT; | |
23 | ||
24 | static DEFINE_SPINLOCK(lock_me_up); | |
25 | ||
26 | static int recursive_loop(int remaining) | |
27 | { | |
28 | char buf[REC_STACK_SIZE]; | |
29 | ||
30 | /* Make sure compiler does not optimize this away. */ | |
31 | memset(buf, (remaining & 0xff) | 0x1, REC_STACK_SIZE); | |
32 | if (!remaining) | |
33 | return 0; | |
34 | else | |
35 | return recursive_loop(remaining - 1); | |
36 | } | |
37 | ||
38 | /* If the depth is negative, use the default, otherwise keep parameter. */ | |
39 | void __init lkdtm_bugs_init(int *recur_param) | |
40 | { | |
41 | if (*recur_param < 0) | |
42 | *recur_param = recur_count; | |
43 | else | |
44 | recur_count = *recur_param; | |
45 | } | |
46 | ||
47 | void lkdtm_PANIC(void) | |
48 | { | |
49 | panic("dumptest"); | |
50 | } | |
51 | ||
52 | void lkdtm_BUG(void) | |
53 | { | |
54 | BUG(); | |
55 | } | |
56 | ||
57 | void lkdtm_WARNING(void) | |
58 | { | |
59 | WARN_ON(1); | |
60 | } | |
61 | ||
62 | void lkdtm_EXCEPTION(void) | |
63 | { | |
64 | *((int *) 0) = 0; | |
65 | } | |
66 | ||
67 | void lkdtm_LOOP(void) | |
68 | { | |
69 | for (;;) | |
70 | ; | |
71 | } | |
72 | ||
73 | void lkdtm_OVERFLOW(void) | |
74 | { | |
75 | (void) recursive_loop(recur_count); | |
76 | } | |
77 | ||
78 | noinline void lkdtm_CORRUPT_STACK(void) | |
79 | { | |
80 | /* Use default char array length that triggers stack protection. */ | |
81 | char data[8]; | |
82 | ||
83 | memset((void *)data, 0, 64); | |
84 | } | |
85 | ||
86 | void lkdtm_UNALIGNED_LOAD_STORE_WRITE(void) | |
87 | { | |
88 | static u8 data[5] __attribute__((aligned(4))) = {1, 2, 3, 4, 5}; | |
89 | u32 *p; | |
90 | u32 val = 0x12345678; | |
91 | ||
92 | p = (u32 *)(data + 1); | |
93 | if (*p == 0) | |
94 | val = 0x87654321; | |
95 | *p = val; | |
96 | } | |
97 | ||
98 | void lkdtm_SOFTLOCKUP(void) | |
99 | { | |
100 | preempt_disable(); | |
101 | for (;;) | |
102 | cpu_relax(); | |
103 | } | |
104 | ||
105 | void lkdtm_HARDLOCKUP(void) | |
106 | { | |
107 | local_irq_disable(); | |
108 | for (;;) | |
109 | cpu_relax(); | |
110 | } | |
111 | ||
112 | void lkdtm_SPINLOCKUP(void) | |
113 | { | |
114 | /* Must be called twice to trigger. */ | |
115 | spin_lock(&lock_me_up); | |
116 | /* Let sparse know we intended to exit holding the lock. */ | |
117 | __release(&lock_me_up); | |
118 | } | |
119 | ||
120 | void lkdtm_HUNG_TASK(void) | |
121 | { | |
122 | set_current_state(TASK_UNINTERRUPTIBLE); | |
123 | schedule(); | |
124 | } | |
125 | ||
126 | void lkdtm_ATOMIC_UNDERFLOW(void) | |
127 | { | |
128 | atomic_t under = ATOMIC_INIT(INT_MIN); | |
129 | ||
130 | pr_info("attempting good atomic increment\n"); | |
131 | atomic_inc(&under); | |
132 | atomic_dec(&under); | |
133 | ||
134 | pr_info("attempting bad atomic underflow\n"); | |
135 | atomic_dec(&under); | |
136 | } | |
137 | ||
138 | void lkdtm_ATOMIC_OVERFLOW(void) | |
139 | { | |
140 | atomic_t over = ATOMIC_INIT(INT_MAX); | |
141 | ||
142 | pr_info("attempting good atomic decrement\n"); | |
143 | atomic_dec(&over); | |
144 | atomic_inc(&over); | |
145 | ||
146 | pr_info("attempting bad atomic overflow\n"); | |
147 | atomic_inc(&over); | |
148 | } |