This source file includes following definitions.
- set_brk
- create_aout_tables
- load_aout_binary
- load_aout_library
- init_aout_binfmt
- exit_aout_binfmt
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9 #include <linux/module.h>
10
11 #include <linux/time.h>
12 #include <linux/kernel.h>
13 #include <linux/mm.h>
14 #include <linux/mman.h>
15 #include <linux/a.out.h>
16 #include <linux/errno.h>
17 #include <linux/signal.h>
18 #include <linux/string.h>
19 #include <linux/fs.h>
20 #include <linux/file.h>
21 #include <linux/stat.h>
22 #include <linux/fcntl.h>
23 #include <linux/ptrace.h>
24 #include <linux/user.h>
25 #include <linux/binfmts.h>
26 #include <linux/personality.h>
27 #include <linux/init.h>
28 #include <linux/jiffies.h>
29 #include <linux/perf_event.h>
30 #include <linux/sched/task_stack.h>
31
32 #include <linux/uaccess.h>
33 #include <asm/pgalloc.h>
34 #include <asm/cacheflush.h>
35 #include <asm/user32.h>
36 #include <asm/ia32.h>
37
38 #undef WARN_OLD
39
40 static int load_aout_binary(struct linux_binprm *);
41 static int load_aout_library(struct file *);
42
43 static struct linux_binfmt aout_format = {
44 .module = THIS_MODULE,
45 .load_binary = load_aout_binary,
46 .load_shlib = load_aout_library,
47 };
48
49 static int set_brk(unsigned long start, unsigned long end)
50 {
51 start = PAGE_ALIGN(start);
52 end = PAGE_ALIGN(end);
53 if (end <= start)
54 return 0;
55 return vm_brk(start, end - start);
56 }
57
58
59
60
61
62
63
64 static u32 __user *create_aout_tables(char __user *p, struct linux_binprm *bprm)
65 {
66 u32 __user *argv, *envp, *sp;
67 int argc = bprm->argc, envc = bprm->envc;
68
69 sp = (u32 __user *) ((-(unsigned long)sizeof(u32)) & (unsigned long) p);
70 sp -= envc+1;
71 envp = sp;
72 sp -= argc+1;
73 argv = sp;
74 put_user((unsigned long) envp, --sp);
75 put_user((unsigned long) argv, --sp);
76 put_user(argc, --sp);
77 current->mm->arg_start = (unsigned long) p;
78 while (argc-- > 0) {
79 char c;
80
81 put_user((u32)(unsigned long)p, argv++);
82 do {
83 get_user(c, p++);
84 } while (c);
85 }
86 put_user(0, argv);
87 current->mm->arg_end = current->mm->env_start = (unsigned long) p;
88 while (envc-- > 0) {
89 char c;
90
91 put_user((u32)(unsigned long)p, envp++);
92 do {
93 get_user(c, p++);
94 } while (c);
95 }
96 put_user(0, envp);
97 current->mm->env_end = (unsigned long) p;
98 return sp;
99 }
100
101
102
103
104
105 static int load_aout_binary(struct linux_binprm *bprm)
106 {
107 unsigned long error, fd_offset, rlim;
108 struct pt_regs *regs = current_pt_regs();
109 struct exec ex;
110 int retval;
111
112 ex = *((struct exec *) bprm->buf);
113 if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != OMAGIC &&
114 N_MAGIC(ex) != QMAGIC && N_MAGIC(ex) != NMAGIC) ||
115 N_TRSIZE(ex) || N_DRSIZE(ex) ||
116 i_size_read(file_inode(bprm->file)) <
117 ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
118 return -ENOEXEC;
119 }
120
121 fd_offset = N_TXTOFF(ex);
122
123
124
125
126
127 rlim = rlimit(RLIMIT_DATA);
128 if (rlim >= RLIM_INFINITY)
129 rlim = ~0;
130 if (ex.a_data + ex.a_bss > rlim)
131 return -ENOMEM;
132
133
134 retval = flush_old_exec(bprm);
135 if (retval)
136 return retval;
137
138
139 set_personality(PER_LINUX);
140 set_personality_ia32(false);
141
142 setup_new_exec(bprm);
143
144 regs->cs = __USER32_CS;
145 regs->r8 = regs->r9 = regs->r10 = regs->r11 = regs->r12 =
146 regs->r13 = regs->r14 = regs->r15 = 0;
147
148 current->mm->end_code = ex.a_text +
149 (current->mm->start_code = N_TXTADDR(ex));
150 current->mm->end_data = ex.a_data +
151 (current->mm->start_data = N_DATADDR(ex));
152 current->mm->brk = ex.a_bss +
153 (current->mm->start_brk = N_BSSADDR(ex));
154
155 retval = setup_arg_pages(bprm, IA32_STACK_TOP, EXSTACK_DEFAULT);
156 if (retval < 0)
157 return retval;
158
159 install_exec_creds(bprm);
160
161 if (N_MAGIC(ex) == OMAGIC) {
162 unsigned long text_addr, map_size;
163
164 text_addr = N_TXTADDR(ex);
165 map_size = ex.a_text+ex.a_data;
166
167 error = vm_brk(text_addr & PAGE_MASK, map_size);
168
169 if (error)
170 return error;
171
172 error = read_code(bprm->file, text_addr, 32,
173 ex.a_text + ex.a_data);
174 if ((signed long)error < 0)
175 return error;
176 } else {
177 #ifdef WARN_OLD
178 static unsigned long error_time, error_time2;
179 if ((ex.a_text & 0xfff || ex.a_data & 0xfff) &&
180 (N_MAGIC(ex) != NMAGIC) &&
181 time_after(jiffies, error_time2 + 5*HZ)) {
182 printk(KERN_NOTICE "executable not page aligned\n");
183 error_time2 = jiffies;
184 }
185
186 if ((fd_offset & ~PAGE_MASK) != 0 &&
187 time_after(jiffies, error_time + 5*HZ)) {
188 printk(KERN_WARNING
189 "fd_offset is not page aligned. Please convert "
190 "program: %pD\n",
191 bprm->file);
192 error_time = jiffies;
193 }
194 #endif
195
196 if (!bprm->file->f_op->mmap || (fd_offset & ~PAGE_MASK) != 0) {
197 error = vm_brk(N_TXTADDR(ex), ex.a_text+ex.a_data);
198 if (error)
199 return error;
200
201 read_code(bprm->file, N_TXTADDR(ex), fd_offset,
202 ex.a_text+ex.a_data);
203 goto beyond_if;
204 }
205
206 error = vm_mmap(bprm->file, N_TXTADDR(ex), ex.a_text,
207 PROT_READ | PROT_EXEC,
208 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE |
209 MAP_EXECUTABLE | MAP_32BIT,
210 fd_offset);
211
212 if (error != N_TXTADDR(ex))
213 return error;
214
215 error = vm_mmap(bprm->file, N_DATADDR(ex), ex.a_data,
216 PROT_READ | PROT_WRITE | PROT_EXEC,
217 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE |
218 MAP_EXECUTABLE | MAP_32BIT,
219 fd_offset + ex.a_text);
220 if (error != N_DATADDR(ex))
221 return error;
222 }
223
224 beyond_if:
225 error = set_brk(current->mm->start_brk, current->mm->brk);
226 if (error)
227 return error;
228
229 set_binfmt(&aout_format);
230
231 current->mm->start_stack =
232 (unsigned long)create_aout_tables((char __user *)bprm->p, bprm);
233
234 loadsegment(fs, 0);
235 loadsegment(ds, __USER32_DS);
236 loadsegment(es, __USER32_DS);
237 load_gs_index(0);
238 (regs)->ip = ex.a_entry;
239 (regs)->sp = current->mm->start_stack;
240 (regs)->flags = 0x200;
241 (regs)->cs = __USER32_CS;
242 (regs)->ss = __USER32_DS;
243 regs->r8 = regs->r9 = regs->r10 = regs->r11 =
244 regs->r12 = regs->r13 = regs->r14 = regs->r15 = 0;
245 set_fs(USER_DS);
246 return 0;
247 }
248
249 static int load_aout_library(struct file *file)
250 {
251 unsigned long bss, start_addr, len, error;
252 int retval;
253 struct exec ex;
254 loff_t pos = 0;
255
256 retval = -ENOEXEC;
257 error = kernel_read(file, &ex, sizeof(ex), &pos);
258 if (error != sizeof(ex))
259 goto out;
260
261
262 if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != QMAGIC) || N_TRSIZE(ex) ||
263 N_DRSIZE(ex) || ((ex.a_entry & 0xfff) && N_MAGIC(ex) == ZMAGIC) ||
264 i_size_read(file_inode(file)) <
265 ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
266 goto out;
267 }
268
269 if (N_FLAGS(ex))
270 goto out;
271
272
273
274
275 start_addr = ex.a_entry & 0xfffff000;
276
277 if ((N_TXTOFF(ex) & ~PAGE_MASK) != 0) {
278 #ifdef WARN_OLD
279 static unsigned long error_time;
280 if (time_after(jiffies, error_time + 5*HZ)) {
281 printk(KERN_WARNING
282 "N_TXTOFF is not page aligned. Please convert "
283 "library: %pD\n",
284 file);
285 error_time = jiffies;
286 }
287 #endif
288 retval = vm_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);
289 if (retval)
290 goto out;
291
292 read_code(file, start_addr, N_TXTOFF(ex),
293 ex.a_text + ex.a_data);
294 retval = 0;
295 goto out;
296 }
297
298 error = vm_mmap(file, start_addr, ex.a_text + ex.a_data,
299 PROT_READ | PROT_WRITE | PROT_EXEC,
300 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_32BIT,
301 N_TXTOFF(ex));
302 retval = error;
303 if (error != start_addr)
304 goto out;
305
306 len = PAGE_ALIGN(ex.a_text + ex.a_data);
307 bss = ex.a_text + ex.a_data + ex.a_bss;
308 if (bss > len) {
309 retval = vm_brk(start_addr + len, bss - len);
310 if (retval)
311 goto out;
312 }
313 retval = 0;
314 out:
315 return retval;
316 }
317
318 static int __init init_aout_binfmt(void)
319 {
320 register_binfmt(&aout_format);
321 return 0;
322 }
323
324 static void __exit exit_aout_binfmt(void)
325 {
326 unregister_binfmt(&aout_format);
327 }
328
329 module_init(init_aout_binfmt);
330 module_exit(exit_aout_binfmt);
331 MODULE_LICENSE("GPL");