Contents of /alx-src/tags/kernel26-2.6.12-alx-r9/fs/binfmt_aout.c
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Wed Mar 4 11:03:09 2009 UTC (15 years, 6 months ago) by niro
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File size: 15181 byte(s)
Wed Mar 4 11:03:09 2009 UTC (15 years, 6 months ago) by niro
File MIME type: text/plain
File size: 15181 byte(s)
Tag kernel26-2.6.12-alx-r9
1 | /* |
2 | * linux/fs/binfmt_aout.c |
3 | * |
4 | * Copyright (C) 1991, 1992, 1996 Linus Torvalds |
5 | */ |
6 | |
7 | #include <linux/module.h> |
8 | |
9 | #include <linux/time.h> |
10 | #include <linux/kernel.h> |
11 | #include <linux/mm.h> |
12 | #include <linux/mman.h> |
13 | #include <linux/a.out.h> |
14 | #include <linux/errno.h> |
15 | #include <linux/signal.h> |
16 | #include <linux/string.h> |
17 | #include <linux/fs.h> |
18 | #include <linux/file.h> |
19 | #include <linux/stat.h> |
20 | #include <linux/fcntl.h> |
21 | #include <linux/ptrace.h> |
22 | #include <linux/user.h> |
23 | #include <linux/slab.h> |
24 | #include <linux/binfmts.h> |
25 | #include <linux/personality.h> |
26 | #include <linux/init.h> |
27 | |
28 | #include <asm/system.h> |
29 | #include <asm/uaccess.h> |
30 | #include <asm/cacheflush.h> |
31 | |
32 | static int load_aout_binary(struct linux_binprm *, struct pt_regs * regs); |
33 | static int load_aout_library(struct file*); |
34 | static int aout_core_dump(long signr, struct pt_regs * regs, struct file *file); |
35 | |
36 | extern void dump_thread(struct pt_regs *, struct user *); |
37 | |
38 | static struct linux_binfmt aout_format = { |
39 | .module = THIS_MODULE, |
40 | .load_binary = load_aout_binary, |
41 | .load_shlib = load_aout_library, |
42 | .core_dump = aout_core_dump, |
43 | .min_coredump = PAGE_SIZE |
44 | }; |
45 | |
46 | #define BAD_ADDR(x) ((unsigned long)(x) >= TASK_SIZE) |
47 | |
48 | static int set_brk(unsigned long start, unsigned long end) |
49 | { |
50 | start = PAGE_ALIGN(start); |
51 | end = PAGE_ALIGN(end); |
52 | if (end > start) { |
53 | unsigned long addr; |
54 | down_write(¤t->mm->mmap_sem); |
55 | addr = do_brk(start, end - start); |
56 | up_write(¤t->mm->mmap_sem); |
57 | if (BAD_ADDR(addr)) |
58 | return addr; |
59 | } |
60 | return 0; |
61 | } |
62 | |
63 | /* |
64 | * These are the only things you should do on a core-file: use only these |
65 | * macros to write out all the necessary info. |
66 | */ |
67 | |
68 | static int dump_write(struct file *file, const void *addr, int nr) |
69 | { |
70 | return file->f_op->write(file, addr, nr, &file->f_pos) == nr; |
71 | } |
72 | |
73 | #define DUMP_WRITE(addr, nr) \ |
74 | if (!dump_write(file, (void *)(addr), (nr))) \ |
75 | goto end_coredump; |
76 | |
77 | #define DUMP_SEEK(offset) \ |
78 | if (file->f_op->llseek) { \ |
79 | if (file->f_op->llseek(file,(offset),0) != (offset)) \ |
80 | goto end_coredump; \ |
81 | } else file->f_pos = (offset) |
82 | |
83 | /* |
84 | * Routine writes a core dump image in the current directory. |
85 | * Currently only a stub-function. |
86 | * |
87 | * Note that setuid/setgid files won't make a core-dump if the uid/gid |
88 | * changed due to the set[u|g]id. It's enforced by the "current->mm->dumpable" |
89 | * field, which also makes sure the core-dumps won't be recursive if the |
90 | * dumping of the process results in another error.. |
91 | */ |
92 | |
93 | static int aout_core_dump(long signr, struct pt_regs * regs, struct file *file) |
94 | { |
95 | mm_segment_t fs; |
96 | int has_dumped = 0; |
97 | unsigned long dump_start, dump_size; |
98 | struct user dump; |
99 | #if defined(__alpha__) |
100 | # define START_DATA(u) (u.start_data) |
101 | #elif defined(__arm__) |
102 | # define START_DATA(u) ((u.u_tsize << PAGE_SHIFT) + u.start_code) |
103 | #elif defined(__sparc__) |
104 | # define START_DATA(u) (u.u_tsize) |
105 | #elif defined(__i386__) || defined(__mc68000__) || defined(__arch_um__) |
106 | # define START_DATA(u) (u.u_tsize << PAGE_SHIFT) |
107 | #endif |
108 | #ifdef __sparc__ |
109 | # define START_STACK(u) ((regs->u_regs[UREG_FP]) & ~(PAGE_SIZE - 1)) |
110 | #else |
111 | # define START_STACK(u) (u.start_stack) |
112 | #endif |
113 | |
114 | fs = get_fs(); |
115 | set_fs(KERNEL_DS); |
116 | has_dumped = 1; |
117 | current->flags |= PF_DUMPCORE; |
118 | strncpy(dump.u_comm, current->comm, sizeof(dump.u_comm)); |
119 | #ifndef __sparc__ |
120 | dump.u_ar0 = (void *)(((unsigned long)(&dump.regs)) - ((unsigned long)(&dump))); |
121 | #endif |
122 | dump.signal = signr; |
123 | dump_thread(regs, &dump); |
124 | |
125 | /* If the size of the dump file exceeds the rlimit, then see what would happen |
126 | if we wrote the stack, but not the data area. */ |
127 | #ifdef __sparc__ |
128 | if ((dump.u_dsize+dump.u_ssize) > |
129 | current->signal->rlim[RLIMIT_CORE].rlim_cur) |
130 | dump.u_dsize = 0; |
131 | #else |
132 | if ((dump.u_dsize+dump.u_ssize+1) * PAGE_SIZE > |
133 | current->signal->rlim[RLIMIT_CORE].rlim_cur) |
134 | dump.u_dsize = 0; |
135 | #endif |
136 | |
137 | /* Make sure we have enough room to write the stack and data areas. */ |
138 | #ifdef __sparc__ |
139 | if ((dump.u_ssize) > |
140 | current->signal->rlim[RLIMIT_CORE].rlim_cur) |
141 | dump.u_ssize = 0; |
142 | #else |
143 | if ((dump.u_ssize+1) * PAGE_SIZE > |
144 | current->signal->rlim[RLIMIT_CORE].rlim_cur) |
145 | dump.u_ssize = 0; |
146 | #endif |
147 | |
148 | /* make sure we actually have a data and stack area to dump */ |
149 | set_fs(USER_DS); |
150 | #ifdef __sparc__ |
151 | if (!access_ok(VERIFY_READ, (void __user *)START_DATA(dump), dump.u_dsize)) |
152 | dump.u_dsize = 0; |
153 | if (!access_ok(VERIFY_READ, (void __user *)START_STACK(dump), dump.u_ssize)) |
154 | dump.u_ssize = 0; |
155 | #else |
156 | if (!access_ok(VERIFY_READ, (void __user *)START_DATA(dump), dump.u_dsize << PAGE_SHIFT)) |
157 | dump.u_dsize = 0; |
158 | if (!access_ok(VERIFY_READ, (void __user *)START_STACK(dump), dump.u_ssize << PAGE_SHIFT)) |
159 | dump.u_ssize = 0; |
160 | #endif |
161 | |
162 | set_fs(KERNEL_DS); |
163 | /* struct user */ |
164 | DUMP_WRITE(&dump,sizeof(dump)); |
165 | /* Now dump all of the user data. Include malloced stuff as well */ |
166 | #ifndef __sparc__ |
167 | DUMP_SEEK(PAGE_SIZE); |
168 | #endif |
169 | /* now we start writing out the user space info */ |
170 | set_fs(USER_DS); |
171 | /* Dump the data area */ |
172 | if (dump.u_dsize != 0) { |
173 | dump_start = START_DATA(dump); |
174 | #ifdef __sparc__ |
175 | dump_size = dump.u_dsize; |
176 | #else |
177 | dump_size = dump.u_dsize << PAGE_SHIFT; |
178 | #endif |
179 | DUMP_WRITE(dump_start,dump_size); |
180 | } |
181 | /* Now prepare to dump the stack area */ |
182 | if (dump.u_ssize != 0) { |
183 | dump_start = START_STACK(dump); |
184 | #ifdef __sparc__ |
185 | dump_size = dump.u_ssize; |
186 | #else |
187 | dump_size = dump.u_ssize << PAGE_SHIFT; |
188 | #endif |
189 | DUMP_WRITE(dump_start,dump_size); |
190 | } |
191 | /* Finally dump the task struct. Not be used by gdb, but could be useful */ |
192 | set_fs(KERNEL_DS); |
193 | DUMP_WRITE(current,sizeof(*current)); |
194 | end_coredump: |
195 | set_fs(fs); |
196 | return has_dumped; |
197 | } |
198 | |
199 | /* |
200 | * create_aout_tables() parses the env- and arg-strings in new user |
201 | * memory and creates the pointer tables from them, and puts their |
202 | * addresses on the "stack", returning the new stack pointer value. |
203 | */ |
204 | static unsigned long __user *create_aout_tables(char __user *p, struct linux_binprm * bprm) |
205 | { |
206 | char __user * __user *argv; |
207 | char __user * __user *envp; |
208 | unsigned long __user *sp; |
209 | int argc = bprm->argc; |
210 | int envc = bprm->envc; |
211 | |
212 | sp = (void __user *)((-(unsigned long)sizeof(char *)) & (unsigned long) p); |
213 | #ifdef __sparc__ |
214 | /* This imposes the proper stack alignment for a new process. */ |
215 | sp = (void __user *) (((unsigned long) sp) & ~7); |
216 | if ((envc+argc+3)&1) --sp; |
217 | #endif |
218 | #ifdef __alpha__ |
219 | /* whee.. test-programs are so much fun. */ |
220 | put_user(0, --sp); |
221 | put_user(0, --sp); |
222 | if (bprm->loader) { |
223 | put_user(0, --sp); |
224 | put_user(0x3eb, --sp); |
225 | put_user(bprm->loader, --sp); |
226 | put_user(0x3ea, --sp); |
227 | } |
228 | put_user(bprm->exec, --sp); |
229 | put_user(0x3e9, --sp); |
230 | #endif |
231 | sp -= envc+1; |
232 | envp = (char __user * __user *) sp; |
233 | sp -= argc+1; |
234 | argv = (char __user * __user *) sp; |
235 | #if defined(__i386__) || defined(__mc68000__) || defined(__arm__) || defined(__arch_um__) |
236 | put_user((unsigned long) envp,--sp); |
237 | put_user((unsigned long) argv,--sp); |
238 | #endif |
239 | put_user(argc,--sp); |
240 | current->mm->arg_start = (unsigned long) p; |
241 | while (argc-->0) { |
242 | char c; |
243 | put_user(p,argv++); |
244 | do { |
245 | get_user(c,p++); |
246 | } while (c); |
247 | } |
248 | put_user(NULL,argv); |
249 | current->mm->arg_end = current->mm->env_start = (unsigned long) p; |
250 | while (envc-->0) { |
251 | char c; |
252 | put_user(p,envp++); |
253 | do { |
254 | get_user(c,p++); |
255 | } while (c); |
256 | } |
257 | put_user(NULL,envp); |
258 | current->mm->env_end = (unsigned long) p; |
259 | return sp; |
260 | } |
261 | |
262 | /* |
263 | * These are the functions used to load a.out style executables and shared |
264 | * libraries. There is no binary dependent code anywhere else. |
265 | */ |
266 | |
267 | static int load_aout_binary(struct linux_binprm * bprm, struct pt_regs * regs) |
268 | { |
269 | struct exec ex; |
270 | unsigned long error; |
271 | unsigned long fd_offset; |
272 | unsigned long rlim; |
273 | int retval; |
274 | |
275 | ex = *((struct exec *) bprm->buf); /* exec-header */ |
276 | if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != OMAGIC && |
277 | N_MAGIC(ex) != QMAGIC && N_MAGIC(ex) != NMAGIC) || |
278 | N_TRSIZE(ex) || N_DRSIZE(ex) || |
279 | i_size_read(bprm->file->f_dentry->d_inode) < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) { |
280 | return -ENOEXEC; |
281 | } |
282 | |
283 | fd_offset = N_TXTOFF(ex); |
284 | |
285 | /* Check initial limits. This avoids letting people circumvent |
286 | * size limits imposed on them by creating programs with large |
287 | * arrays in the data or bss. |
288 | */ |
289 | rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur; |
290 | if (rlim >= RLIM_INFINITY) |
291 | rlim = ~0; |
292 | if (ex.a_data + ex.a_bss > rlim) |
293 | return -ENOMEM; |
294 | |
295 | /* Flush all traces of the currently running executable */ |
296 | retval = flush_old_exec(bprm); |
297 | if (retval) |
298 | return retval; |
299 | |
300 | /* OK, This is the point of no return */ |
301 | #if defined(__alpha__) |
302 | SET_AOUT_PERSONALITY(bprm, ex); |
303 | #elif defined(__sparc__) |
304 | set_personality(PER_SUNOS); |
305 | #if !defined(__sparc_v9__) |
306 | memcpy(¤t->thread.core_exec, &ex, sizeof(struct exec)); |
307 | #endif |
308 | #else |
309 | set_personality(PER_LINUX); |
310 | #endif |
311 | |
312 | current->mm->end_code = ex.a_text + |
313 | (current->mm->start_code = N_TXTADDR(ex)); |
314 | current->mm->end_data = ex.a_data + |
315 | (current->mm->start_data = N_DATADDR(ex)); |
316 | current->mm->brk = ex.a_bss + |
317 | (current->mm->start_brk = N_BSSADDR(ex)); |
318 | current->mm->free_area_cache = current->mm->mmap_base; |
319 | |
320 | set_mm_counter(current->mm, rss, 0); |
321 | current->mm->mmap = NULL; |
322 | compute_creds(bprm); |
323 | current->flags &= ~PF_FORKNOEXEC; |
324 | #ifdef __sparc__ |
325 | if (N_MAGIC(ex) == NMAGIC) { |
326 | loff_t pos = fd_offset; |
327 | /* Fuck me plenty... */ |
328 | /* <AOL></AOL> */ |
329 | down_write(¤t->mm->mmap_sem); |
330 | error = do_brk(N_TXTADDR(ex), ex.a_text); |
331 | up_write(¤t->mm->mmap_sem); |
332 | bprm->file->f_op->read(bprm->file, (char *) N_TXTADDR(ex), |
333 | ex.a_text, &pos); |
334 | down_write(¤t->mm->mmap_sem); |
335 | error = do_brk(N_DATADDR(ex), ex.a_data); |
336 | up_write(¤t->mm->mmap_sem); |
337 | bprm->file->f_op->read(bprm->file, (char *) N_DATADDR(ex), |
338 | ex.a_data, &pos); |
339 | goto beyond_if; |
340 | } |
341 | #endif |
342 | |
343 | if (N_MAGIC(ex) == OMAGIC) { |
344 | unsigned long text_addr, map_size; |
345 | loff_t pos; |
346 | |
347 | text_addr = N_TXTADDR(ex); |
348 | |
349 | #if defined(__alpha__) || defined(__sparc__) |
350 | pos = fd_offset; |
351 | map_size = ex.a_text+ex.a_data + PAGE_SIZE - 1; |
352 | #else |
353 | pos = 32; |
354 | map_size = ex.a_text+ex.a_data; |
355 | #endif |
356 | down_write(¤t->mm->mmap_sem); |
357 | error = do_brk(text_addr & PAGE_MASK, map_size); |
358 | up_write(¤t->mm->mmap_sem); |
359 | if (error != (text_addr & PAGE_MASK)) { |
360 | send_sig(SIGKILL, current, 0); |
361 | return error; |
362 | } |
363 | |
364 | error = bprm->file->f_op->read(bprm->file, |
365 | (char __user *)text_addr, |
366 | ex.a_text+ex.a_data, &pos); |
367 | if ((signed long)error < 0) { |
368 | send_sig(SIGKILL, current, 0); |
369 | return error; |
370 | } |
371 | |
372 | flush_icache_range(text_addr, text_addr+ex.a_text+ex.a_data); |
373 | } else { |
374 | static unsigned long error_time, error_time2; |
375 | if ((ex.a_text & 0xfff || ex.a_data & 0xfff) && |
376 | (N_MAGIC(ex) != NMAGIC) && (jiffies-error_time2) > 5*HZ) |
377 | { |
378 | printk(KERN_NOTICE "executable not page aligned\n"); |
379 | error_time2 = jiffies; |
380 | } |
381 | |
382 | if ((fd_offset & ~PAGE_MASK) != 0 && |
383 | (jiffies-error_time) > 5*HZ) |
384 | { |
385 | printk(KERN_WARNING |
386 | "fd_offset is not page aligned. Please convert program: %s\n", |
387 | bprm->file->f_dentry->d_name.name); |
388 | error_time = jiffies; |
389 | } |
390 | |
391 | if (!bprm->file->f_op->mmap||((fd_offset & ~PAGE_MASK) != 0)) { |
392 | loff_t pos = fd_offset; |
393 | down_write(¤t->mm->mmap_sem); |
394 | do_brk(N_TXTADDR(ex), ex.a_text+ex.a_data); |
395 | up_write(¤t->mm->mmap_sem); |
396 | bprm->file->f_op->read(bprm->file, |
397 | (char __user *)N_TXTADDR(ex), |
398 | ex.a_text+ex.a_data, &pos); |
399 | flush_icache_range((unsigned long) N_TXTADDR(ex), |
400 | (unsigned long) N_TXTADDR(ex) + |
401 | ex.a_text+ex.a_data); |
402 | goto beyond_if; |
403 | } |
404 | |
405 | down_write(¤t->mm->mmap_sem); |
406 | error = do_mmap(bprm->file, N_TXTADDR(ex), ex.a_text, |
407 | PROT_READ | PROT_EXEC, |
408 | MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE, |
409 | fd_offset); |
410 | up_write(¤t->mm->mmap_sem); |
411 | |
412 | if (error != N_TXTADDR(ex)) { |
413 | send_sig(SIGKILL, current, 0); |
414 | return error; |
415 | } |
416 | |
417 | down_write(¤t->mm->mmap_sem); |
418 | error = do_mmap(bprm->file, N_DATADDR(ex), ex.a_data, |
419 | PROT_READ | PROT_WRITE | PROT_EXEC, |
420 | MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE, |
421 | fd_offset + ex.a_text); |
422 | up_write(¤t->mm->mmap_sem); |
423 | if (error != N_DATADDR(ex)) { |
424 | send_sig(SIGKILL, current, 0); |
425 | return error; |
426 | } |
427 | } |
428 | beyond_if: |
429 | set_binfmt(&aout_format); |
430 | |
431 | retval = set_brk(current->mm->start_brk, current->mm->brk); |
432 | if (retval < 0) { |
433 | send_sig(SIGKILL, current, 0); |
434 | return retval; |
435 | } |
436 | |
437 | retval = setup_arg_pages(bprm, STACK_TOP, EXSTACK_DEFAULT); |
438 | if (retval < 0) { |
439 | /* Someone check-me: is this error path enough? */ |
440 | send_sig(SIGKILL, current, 0); |
441 | return retval; |
442 | } |
443 | |
444 | current->mm->start_stack = |
445 | (unsigned long) create_aout_tables((char __user *) bprm->p, bprm); |
446 | #ifdef __alpha__ |
447 | regs->gp = ex.a_gpvalue; |
448 | #endif |
449 | start_thread(regs, ex.a_entry, current->mm->start_stack); |
450 | if (unlikely(current->ptrace & PT_PTRACED)) { |
451 | if (current->ptrace & PT_TRACE_EXEC) |
452 | ptrace_notify ((PTRACE_EVENT_EXEC << 8) | SIGTRAP); |
453 | else |
454 | send_sig(SIGTRAP, current, 0); |
455 | } |
456 | return 0; |
457 | } |
458 | |
459 | static int load_aout_library(struct file *file) |
460 | { |
461 | struct inode * inode; |
462 | unsigned long bss, start_addr, len; |
463 | unsigned long error; |
464 | int retval; |
465 | struct exec ex; |
466 | |
467 | inode = file->f_dentry->d_inode; |
468 | |
469 | retval = -ENOEXEC; |
470 | error = kernel_read(file, 0, (char *) &ex, sizeof(ex)); |
471 | if (error != sizeof(ex)) |
472 | goto out; |
473 | |
474 | /* We come in here for the regular a.out style of shared libraries */ |
475 | if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != QMAGIC) || N_TRSIZE(ex) || |
476 | N_DRSIZE(ex) || ((ex.a_entry & 0xfff) && N_MAGIC(ex) == ZMAGIC) || |
477 | i_size_read(inode) < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) { |
478 | goto out; |
479 | } |
480 | |
481 | if (N_FLAGS(ex)) |
482 | goto out; |
483 | |
484 | /* For QMAGIC, the starting address is 0x20 into the page. We mask |
485 | this off to get the starting address for the page */ |
486 | |
487 | start_addr = ex.a_entry & 0xfffff000; |
488 | |
489 | if ((N_TXTOFF(ex) & ~PAGE_MASK) != 0) { |
490 | static unsigned long error_time; |
491 | loff_t pos = N_TXTOFF(ex); |
492 | |
493 | if ((jiffies-error_time) > 5*HZ) |
494 | { |
495 | printk(KERN_WARNING |
496 | "N_TXTOFF is not page aligned. Please convert library: %s\n", |
497 | file->f_dentry->d_name.name); |
498 | error_time = jiffies; |
499 | } |
500 | down_write(¤t->mm->mmap_sem); |
501 | do_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss); |
502 | up_write(¤t->mm->mmap_sem); |
503 | |
504 | file->f_op->read(file, (char __user *)start_addr, |
505 | ex.a_text + ex.a_data, &pos); |
506 | flush_icache_range((unsigned long) start_addr, |
507 | (unsigned long) start_addr + ex.a_text + ex.a_data); |
508 | |
509 | retval = 0; |
510 | goto out; |
511 | } |
512 | /* Now use mmap to map the library into memory. */ |
513 | down_write(¤t->mm->mmap_sem); |
514 | error = do_mmap(file, start_addr, ex.a_text + ex.a_data, |
515 | PROT_READ | PROT_WRITE | PROT_EXEC, |
516 | MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE, |
517 | N_TXTOFF(ex)); |
518 | up_write(¤t->mm->mmap_sem); |
519 | retval = error; |
520 | if (error != start_addr) |
521 | goto out; |
522 | |
523 | len = PAGE_ALIGN(ex.a_text + ex.a_data); |
524 | bss = ex.a_text + ex.a_data + ex.a_bss; |
525 | if (bss > len) { |
526 | down_write(¤t->mm->mmap_sem); |
527 | error = do_brk(start_addr + len, bss - len); |
528 | up_write(¤t->mm->mmap_sem); |
529 | retval = error; |
530 | if (error != start_addr + len) |
531 | goto out; |
532 | } |
533 | retval = 0; |
534 | out: |
535 | return retval; |
536 | } |
537 | |
538 | static int __init init_aout_binfmt(void) |
539 | { |
540 | return register_binfmt(&aout_format); |
541 | } |
542 | |
543 | static void __exit exit_aout_binfmt(void) |
544 | { |
545 | unregister_binfmt(&aout_format); |
546 | } |
547 | |
548 | core_initcall(init_aout_binfmt); |
549 | module_exit(exit_aout_binfmt); |
550 | MODULE_LICENSE("GPL"); |