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6#include <linux/sched.h>
7#include <linux/kernel.h>
8#include <linux/capability.h>
9#include <linux/errno.h>
10#include <linux/types.h>
11#include <linux/ioport.h>
12#include <linux/smp.h>
13#include <linux/stddef.h>
14#include <linux/slab.h>
15#include <linux/thread_info.h>
16#include <linux/syscalls.h>
17#include <linux/bitmap.h>
18#include <asm/syscalls.h>
19
20
21
22
23asmlinkage long sys_ioperm(unsigned long from, unsigned long num, int turn_on)
24{
25 struct thread_struct *t = ¤t->thread;
26 struct tss_struct *tss;
27 unsigned int i, max_long, bytes, bytes_updated;
28
29 if ((from + num <= from) || (from + num > IO_BITMAP_BITS))
30 return -EINVAL;
31 if (turn_on && !capable(CAP_SYS_RAWIO))
32 return -EPERM;
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34
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36
37
38
39 if (!t->io_bitmap_ptr) {
40 unsigned long *bitmap = kmalloc(IO_BITMAP_BYTES, GFP_KERNEL);
41
42 if (!bitmap)
43 return -ENOMEM;
44
45 memset(bitmap, 0xff, IO_BITMAP_BYTES);
46 t->io_bitmap_ptr = bitmap;
47 set_thread_flag(TIF_IO_BITMAP);
48 }
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54
55
56
57 tss = &per_cpu(cpu_tss, get_cpu());
58
59 if (turn_on)
60 bitmap_clear(t->io_bitmap_ptr, from, num);
61 else
62 bitmap_set(t->io_bitmap_ptr, from, num);
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64
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66
67
68 max_long = 0;
69 for (i = 0; i < IO_BITMAP_LONGS; i++)
70 if (t->io_bitmap_ptr[i] != ~0UL)
71 max_long = i;
72
73 bytes = (max_long + 1) * sizeof(unsigned long);
74 bytes_updated = max(bytes, t->io_bitmap_max);
75
76 t->io_bitmap_max = bytes;
77
78
79 memcpy(tss->io_bitmap, t->io_bitmap_ptr, bytes_updated);
80
81 put_cpu();
82
83 return 0;
84}
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95
96SYSCALL_DEFINE1(iopl, unsigned int, level)
97{
98 struct pt_regs *regs = current_pt_regs();
99 unsigned int old = (regs->flags >> 12) & 3;
100 struct thread_struct *t = ¤t->thread;
101
102 if (level > 3)
103 return -EINVAL;
104
105 if (level > old) {
106 if (!capable(CAP_SYS_RAWIO))
107 return -EPERM;
108 }
109 regs->flags = (regs->flags & ~X86_EFLAGS_IOPL) | (level << 12);
110 t->iopl = level << 12;
111 set_iopl_mask(t->iopl);
112
113 return 0;
114}
115