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11#include <linux/module.h>
12#include <linux/string.h>
13#include <linux/stat.h>
14#include <linux/binfmts.h>
15#include <linux/elf.h>
16#include <linux/init.h>
17#include <linux/fs.h>
18#include <linux/file.h>
19#include <linux/errno.h>
20
21
22#define EM86_INTERP "/usr/bin/em86"
23#define EM86_I_NAME "em86"
24
25static int load_em86(struct linux_binprm *bprm)
26{
27 char *interp, *i_name, *i_arg;
28 struct file * file;
29 int retval;
30 struct elfhdr elf_ex;
31
32
33 elf_ex = *((struct elfhdr *)bprm->buf);
34
35 if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
36 return -ENOEXEC;
37
38
39 if ((elf_ex.e_type != ET_EXEC && elf_ex.e_type != ET_DYN) ||
40 (!((elf_ex.e_machine == EM_386) || (elf_ex.e_machine == EM_486))) ||
41 (!bprm->file->f_op || !bprm->file->f_op->mmap)) {
42 return -ENOEXEC;
43 }
44
45 allow_write_access(bprm->file);
46 fput(bprm->file);
47 bprm->file = NULL;
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51
52 interp = EM86_INTERP;
53 i_name = EM86_I_NAME;
54 i_arg = NULL;
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63
64 remove_arg_zero(bprm);
65 retval = copy_strings_kernel(1, &bprm->filename, bprm);
66 if (retval < 0) return retval;
67 bprm->argc++;
68 if (i_arg) {
69 retval = copy_strings_kernel(1, &i_arg, bprm);
70 if (retval < 0) return retval;
71 bprm->argc++;
72 }
73 retval = copy_strings_kernel(1, &i_name, bprm);
74 if (retval < 0) return retval;
75 bprm->argc++;
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81
82 file = open_exec(interp);
83 if (IS_ERR(file))
84 return PTR_ERR(file);
85
86 bprm->file = file;
87
88 retval = prepare_binprm(bprm);
89 if (retval < 0)
90 return retval;
91
92 return search_binary_handler(bprm);
93}
94
95static struct linux_binfmt em86_format = {
96 .module = THIS_MODULE,
97 .load_binary = load_em86,
98};
99
100static int __init init_em86_binfmt(void)
101{
102 register_binfmt(&em86_format);
103 return 0;
104}
105
106static void __exit exit_em86_binfmt(void)
107{
108 unregister_binfmt(&em86_format);
109}
110
111core_initcall(init_em86_binfmt);
112module_exit(exit_em86_binfmt);
113MODULE_LICENSE("GPL");
114