Commit | Line | Data |
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1da177e4 LT |
1 | /****************************************************************************/ |
2 | /* | |
3 | * linux/fs/binfmt_flat.c | |
4 | * | |
5 | * Copyright (C) 2000-2003 David McCullough <davidm@snapgear.com> | |
6 | * Copyright (C) 2002 Greg Ungerer <gerg@snapgear.com> | |
7 | * Copyright (C) 2002 SnapGear, by Paul Dale <pauli@snapgear.com> | |
8 | * Copyright (C) 2000, 2001 Lineo, by David McCullough <davidm@lineo.com> | |
9 | * based heavily on: | |
10 | * | |
11 | * linux/fs/binfmt_aout.c: | |
12 | * Copyright (C) 1991, 1992, 1996 Linus Torvalds | |
13 | * linux/fs/binfmt_flat.c for 2.0 kernel | |
14 | * Copyright (C) 1998 Kenneth Albanowski <kjahds@kjahds.com> | |
15 | * JAN/99 -- coded full program relocation (gerg@snapgear.com) | |
16 | */ | |
17 | ||
4adbb6ac NP |
18 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
19 | ||
1da177e4 LT |
20 | #include <linux/kernel.h> |
21 | #include <linux/sched.h> | |
22 | #include <linux/mm.h> | |
23 | #include <linux/mman.h> | |
1da177e4 LT |
24 | #include <linux/errno.h> |
25 | #include <linux/signal.h> | |
26 | #include <linux/string.h> | |
27 | #include <linux/fs.h> | |
28 | #include <linux/file.h> | |
1da177e4 LT |
29 | #include <linux/ptrace.h> |
30 | #include <linux/user.h> | |
31 | #include <linux/slab.h> | |
32 | #include <linux/binfmts.h> | |
33 | #include <linux/personality.h> | |
34 | #include <linux/init.h> | |
35 | #include <linux/flat.h> | |
13c3f50c | 36 | #include <linux/uaccess.h> |
1da177e4 LT |
37 | |
38 | #include <asm/byteorder.h> | |
1da177e4 LT |
39 | #include <asm/unaligned.h> |
40 | #include <asm/cacheflush.h> | |
c3dc5bec | 41 | #include <asm/page.h> |
1da177e4 LT |
42 | |
43 | /****************************************************************************/ | |
44 | ||
c3dc5bec | 45 | /* |
2e94de8a MF |
46 | * User data (data section and bss) needs to be aligned. |
47 | * We pick 0x20 here because it is the max value elf2flt has always | |
48 | * used in producing FLAT files, and because it seems to be large | |
49 | * enough to make all the gcc alignment related tests happy. | |
50 | */ | |
51 | #define FLAT_DATA_ALIGN (0x20) | |
52 | ||
53 | /* | |
54 | * User data (stack) also needs to be aligned. | |
55 | * Here we can be a bit looser than the data sections since this | |
56 | * needs to only meet arch ABI requirements. | |
c3dc5bec | 57 | */ |
2952095c | 58 | #define FLAT_STACK_ALIGN max_t(unsigned long, sizeof(void *), ARCH_SLAB_MINALIGN) |
c3dc5bec | 59 | |
1da177e4 LT |
60 | #define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */ |
61 | #define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */ | |
62 | ||
63 | struct lib_info { | |
64 | struct { | |
65 | unsigned long start_code; /* Start of text segment */ | |
66 | unsigned long start_data; /* Start of data segment */ | |
67 | unsigned long start_brk; /* End of data segment */ | |
68 | unsigned long text_len; /* Length of text segment */ | |
69 | unsigned long entry; /* Start address for this module */ | |
70 | unsigned long build_date; /* When this one was compiled */ | |
13c3f50c | 71 | bool loaded; /* Has this library been loaded? */ |
1da177e4 LT |
72 | } lib_list[MAX_SHARED_LIBS]; |
73 | }; | |
74 | ||
75 | #ifdef CONFIG_BINFMT_SHARED_FLAT | |
76 | static int load_flat_shared_library(int id, struct lib_info *p); | |
77 | #endif | |
78 | ||
71613c3b | 79 | static int load_flat_binary(struct linux_binprm *); |
f6151dfe | 80 | static int flat_core_dump(struct coredump_params *cprm); |
1da177e4 | 81 | |
1da177e4 LT |
82 | static struct linux_binfmt flat_format = { |
83 | .module = THIS_MODULE, | |
84 | .load_binary = load_flat_binary, | |
85 | .core_dump = flat_core_dump, | |
86 | .min_coredump = PAGE_SIZE | |
87 | }; | |
88 | ||
89 | /****************************************************************************/ | |
90 | /* | |
91 | * Routine writes a core dump image in the current directory. | |
92 | * Currently only a stub-function. | |
93 | */ | |
94 | ||
f6151dfe | 95 | static int flat_core_dump(struct coredump_params *cprm) |
1da177e4 | 96 | { |
4adbb6ac NP |
97 | pr_warn("Process %s:%d received signr %d and should have core dumped\n", |
98 | current->comm, current->pid, cprm->siginfo->si_signo); | |
13c3f50c | 99 | return 1; |
1da177e4 LT |
100 | } |
101 | ||
102 | /****************************************************************************/ | |
103 | /* | |
104 | * create_flat_tables() parses the env- and arg-strings in new user | |
105 | * memory and creates the pointer tables from them, and puts their | |
a97d157d | 106 | * addresses on the "stack", recording the new stack pointer value. |
1da177e4 LT |
107 | */ |
108 | ||
a97d157d | 109 | static int create_flat_tables(struct linux_binprm *bprm, unsigned long arg_start) |
1da177e4 | 110 | { |
a97d157d NP |
111 | char __user *p; |
112 | unsigned long __user *sp; | |
113 | long i, len; | |
1da177e4 | 114 | |
a97d157d NP |
115 | p = (char __user *)arg_start; |
116 | sp = (unsigned long __user *)current->mm->start_stack; | |
117 | ||
118 | sp -= bprm->envc + 1; | |
119 | sp -= bprm->argc + 1; | |
120 | sp -= flat_argvp_envp_on_stack() ? 2 : 0; | |
121 | sp -= 1; /* &argc */ | |
122 | ||
123 | current->mm->start_stack = (unsigned long)sp & -FLAT_STACK_ALIGN; | |
124 | sp = (unsigned long __user *)current->mm->start_stack; | |
125 | ||
126 | __put_user(bprm->argc, sp++); | |
1da177e4 | 127 | if (flat_argvp_envp_on_stack()) { |
a97d157d NP |
128 | unsigned long argv, envp; |
129 | argv = (unsigned long)(sp + 2); | |
130 | envp = (unsigned long)(sp + 2 + bprm->argc + 1); | |
131 | __put_user(argv, sp++); | |
132 | __put_user(envp, sp++); | |
133 | } | |
134 | ||
135 | current->mm->arg_start = (unsigned long)p; | |
136 | for (i = bprm->argc; i > 0; i--) { | |
137 | __put_user((unsigned long)p, sp++); | |
138 | len = strnlen_user(p, MAX_ARG_STRLEN); | |
139 | if (!len || len > MAX_ARG_STRLEN) | |
140 | return -EINVAL; | |
141 | p += len; | |
142 | } | |
143 | __put_user(0, sp++); | |
144 | current->mm->arg_end = (unsigned long)p; | |
145 | ||
146 | current->mm->env_start = (unsigned long) p; | |
147 | for (i = bprm->envc; i > 0; i--) { | |
148 | __put_user((unsigned long)p, sp++); | |
149 | len = strnlen_user(p, MAX_ARG_STRLEN); | |
150 | if (!len || len > MAX_ARG_STRLEN) | |
151 | return -EINVAL; | |
152 | p += len; | |
153 | } | |
154 | __put_user(0, sp++); | |
155 | current->mm->env_end = (unsigned long)p; | |
156 | ||
157 | return 0; | |
1da177e4 LT |
158 | } |
159 | ||
160 | /****************************************************************************/ | |
161 | ||
162 | #ifdef CONFIG_BINFMT_ZFLAT | |
163 | ||
164 | #include <linux/zlib.h> | |
165 | ||
166 | #define LBUFSIZE 4000 | |
167 | ||
168 | /* gzip flag byte */ | |
169 | #define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */ | |
170 | #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */ | |
171 | #define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */ | |
172 | #define ORIG_NAME 0x08 /* bit 3 set: original file name present */ | |
173 | #define COMMENT 0x10 /* bit 4 set: file comment present */ | |
174 | #define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */ | |
175 | #define RESERVED 0xC0 /* bit 6,7: reserved */ | |
176 | ||
177 | static int decompress_exec( | |
178 | struct linux_binprm *bprm, | |
179 | unsigned long offset, | |
180 | char *dst, | |
181 | long len, | |
182 | int fd) | |
183 | { | |
184 | unsigned char *buf; | |
185 | z_stream strm; | |
186 | loff_t fpos; | |
187 | int ret, retval; | |
188 | ||
4adbb6ac | 189 | pr_debug("decompress_exec(offset=%lx,buf=%p,len=%lx)\n", offset, dst, len); |
1da177e4 LT |
190 | |
191 | memset(&strm, 0, sizeof(strm)); | |
192 | strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL); | |
193 | if (strm.workspace == NULL) { | |
4adbb6ac | 194 | pr_debug("no memory for decompress workspace\n"); |
1da177e4 LT |
195 | return -ENOMEM; |
196 | } | |
197 | buf = kmalloc(LBUFSIZE, GFP_KERNEL); | |
198 | if (buf == NULL) { | |
4adbb6ac | 199 | pr_debug("no memory for read buffer\n"); |
1da177e4 LT |
200 | retval = -ENOMEM; |
201 | goto out_free; | |
202 | } | |
203 | ||
204 | /* Read in first chunk of data and parse gzip header. */ | |
205 | fpos = offset; | |
3dc20cb2 | 206 | ret = kernel_read(bprm->file, offset, buf, LBUFSIZE); |
1da177e4 LT |
207 | |
208 | strm.next_in = buf; | |
209 | strm.avail_in = ret; | |
210 | strm.total_in = 0; | |
3dc20cb2 | 211 | fpos += ret; |
1da177e4 LT |
212 | |
213 | retval = -ENOEXEC; | |
214 | ||
215 | /* Check minimum size -- gzip header */ | |
216 | if (ret < 10) { | |
4adbb6ac | 217 | pr_debug("file too small?\n"); |
1da177e4 LT |
218 | goto out_free_buf; |
219 | } | |
220 | ||
221 | /* Check gzip magic number */ | |
222 | if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) { | |
4adbb6ac | 223 | pr_debug("unknown compression magic?\n"); |
1da177e4 LT |
224 | goto out_free_buf; |
225 | } | |
226 | ||
227 | /* Check gzip method */ | |
228 | if (buf[2] != 8) { | |
4adbb6ac | 229 | pr_debug("unknown compression method?\n"); |
1da177e4 LT |
230 | goto out_free_buf; |
231 | } | |
232 | /* Check gzip flags */ | |
233 | if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) || | |
234 | (buf[3] & RESERVED)) { | |
4adbb6ac | 235 | pr_debug("unknown flags?\n"); |
1da177e4 LT |
236 | goto out_free_buf; |
237 | } | |
238 | ||
239 | ret = 10; | |
240 | if (buf[3] & EXTRA_FIELD) { | |
241 | ret += 2 + buf[10] + (buf[11] << 8); | |
13c3f50c | 242 | if (unlikely(ret >= LBUFSIZE)) { |
4adbb6ac | 243 | pr_debug("buffer overflow (EXTRA)?\n"); |
1da177e4 LT |
244 | goto out_free_buf; |
245 | } | |
246 | } | |
247 | if (buf[3] & ORIG_NAME) { | |
f4cfb18d | 248 | while (ret < LBUFSIZE && buf[ret++] != 0) |
1da177e4 | 249 | ; |
13c3f50c | 250 | if (unlikely(ret == LBUFSIZE)) { |
4adbb6ac | 251 | pr_debug("buffer overflow (ORIG_NAME)?\n"); |
1da177e4 LT |
252 | goto out_free_buf; |
253 | } | |
254 | } | |
255 | if (buf[3] & COMMENT) { | |
f4cfb18d | 256 | while (ret < LBUFSIZE && buf[ret++] != 0) |
1da177e4 | 257 | ; |
13c3f50c | 258 | if (unlikely(ret == LBUFSIZE)) { |
4adbb6ac | 259 | pr_debug("buffer overflow (COMMENT)?\n"); |
1da177e4 LT |
260 | goto out_free_buf; |
261 | } | |
262 | } | |
263 | ||
264 | strm.next_in += ret; | |
265 | strm.avail_in -= ret; | |
266 | ||
267 | strm.next_out = dst; | |
268 | strm.avail_out = len; | |
269 | strm.total_out = 0; | |
270 | ||
271 | if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) { | |
4adbb6ac | 272 | pr_debug("zlib init failed?\n"); |
1da177e4 LT |
273 | goto out_free_buf; |
274 | } | |
275 | ||
276 | while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) { | |
3dc20cb2 | 277 | ret = kernel_read(bprm->file, fpos, buf, LBUFSIZE); |
1da177e4 LT |
278 | if (ret <= 0) |
279 | break; | |
1da177e4 LT |
280 | len -= ret; |
281 | ||
282 | strm.next_in = buf; | |
283 | strm.avail_in = ret; | |
284 | strm.total_in = 0; | |
3dc20cb2 | 285 | fpos += ret; |
1da177e4 LT |
286 | } |
287 | ||
288 | if (ret < 0) { | |
4adbb6ac | 289 | pr_debug("decompression failed (%d), %s\n", |
1da177e4 LT |
290 | ret, strm.msg); |
291 | goto out_zlib; | |
292 | } | |
293 | ||
294 | retval = 0; | |
295 | out_zlib: | |
296 | zlib_inflateEnd(&strm); | |
297 | out_free_buf: | |
298 | kfree(buf); | |
299 | out_free: | |
300 | kfree(strm.workspace); | |
1da177e4 LT |
301 | return retval; |
302 | } | |
303 | ||
304 | #endif /* CONFIG_BINFMT_ZFLAT */ | |
305 | ||
306 | /****************************************************************************/ | |
307 | ||
308 | static unsigned long | |
309 | calc_reloc(unsigned long r, struct lib_info *p, int curid, int internalp) | |
310 | { | |
311 | unsigned long addr; | |
312 | int id; | |
313 | unsigned long start_brk; | |
314 | unsigned long start_data; | |
315 | unsigned long text_len; | |
316 | unsigned long start_code; | |
317 | ||
318 | #ifdef CONFIG_BINFMT_SHARED_FLAT | |
319 | if (r == 0) | |
320 | id = curid; /* Relocs of 0 are always self referring */ | |
321 | else { | |
322 | id = (r >> 24) & 0xff; /* Find ID for this reloc */ | |
323 | r &= 0x00ffffff; /* Trim ID off here */ | |
324 | } | |
325 | if (id >= MAX_SHARED_LIBS) { | |
4adbb6ac | 326 | pr_err("reference 0x%lx to shared library %d", r, id); |
1da177e4 LT |
327 | goto failed; |
328 | } | |
329 | if (curid != id) { | |
330 | if (internalp) { | |
4adbb6ac NP |
331 | pr_err("reloc address 0x%lx not in same module " |
332 | "(%d != %d)", r, curid, id); | |
1da177e4 | 333 | goto failed; |
13c3f50c NP |
334 | } else if (!p->lib_list[id].loaded && |
335 | load_flat_shared_library(id, p) < 0) { | |
4adbb6ac | 336 | pr_err("failed to load library %d", id); |
1da177e4 LT |
337 | goto failed; |
338 | } | |
339 | /* Check versioning information (i.e. time stamps) */ | |
340 | if (p->lib_list[id].build_date && p->lib_list[curid].build_date && | |
341 | p->lib_list[curid].build_date < p->lib_list[id].build_date) { | |
4adbb6ac | 342 | pr_err("library %d is younger than %d", id, curid); |
1da177e4 LT |
343 | goto failed; |
344 | } | |
345 | } | |
346 | #else | |
347 | id = 0; | |
348 | #endif | |
349 | ||
350 | start_brk = p->lib_list[id].start_brk; | |
351 | start_data = p->lib_list[id].start_data; | |
352 | start_code = p->lib_list[id].start_code; | |
353 | text_len = p->lib_list[id].text_len; | |
354 | ||
355 | if (!flat_reloc_valid(r, start_brk - start_data + text_len)) { | |
4adbb6ac | 356 | pr_err("reloc outside program 0x%lx (0 - 0x%lx/0x%lx)", |
13c3f50c | 357 | r, start_brk-start_data+text_len, text_len); |
1da177e4 LT |
358 | goto failed; |
359 | } | |
360 | ||
361 | if (r < text_len) /* In text segment */ | |
362 | addr = r + start_code; | |
363 | else /* In data segment */ | |
364 | addr = r - text_len + start_data; | |
365 | ||
366 | /* Range checked already above so doing the range tests is redundant...*/ | |
13c3f50c | 367 | return addr; |
1da177e4 LT |
368 | |
369 | failed: | |
4adbb6ac | 370 | pr_cont(", killing %s!\n", current->comm); |
1da177e4 LT |
371 | send_sig(SIGSEGV, current, 0); |
372 | ||
373 | return RELOC_FAILED; | |
374 | } | |
375 | ||
376 | /****************************************************************************/ | |
377 | ||
34303435 | 378 | static void old_reloc(unsigned long rl) |
1da177e4 | 379 | { |
13c3f50c | 380 | static const char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" }; |
1da177e4 LT |
381 | flat_v2_reloc_t r; |
382 | unsigned long *ptr; | |
13c3f50c | 383 | |
1da177e4 LT |
384 | r.value = rl; |
385 | #if defined(CONFIG_COLDFIRE) | |
386 | ptr = (unsigned long *) (current->mm->start_code + r.reloc.offset); | |
387 | #else | |
388 | ptr = (unsigned long *) (current->mm->start_data + r.reloc.offset); | |
389 | #endif | |
390 | ||
4adbb6ac NP |
391 | pr_debug("Relocation of variable at DATASEG+%x " |
392 | "(address %p, currently %lx) into segment %s\n", | |
393 | r.reloc.offset, ptr, *ptr, segment[r.reloc.type]); | |
13c3f50c | 394 | |
1da177e4 LT |
395 | switch (r.reloc.type) { |
396 | case OLD_FLAT_RELOC_TYPE_TEXT: | |
397 | *ptr += current->mm->start_code; | |
398 | break; | |
399 | case OLD_FLAT_RELOC_TYPE_DATA: | |
400 | *ptr += current->mm->start_data; | |
401 | break; | |
402 | case OLD_FLAT_RELOC_TYPE_BSS: | |
403 | *ptr += current->mm->end_data; | |
404 | break; | |
405 | default: | |
4adbb6ac | 406 | pr_err("Unknown relocation type=%x\n", r.reloc.type); |
1da177e4 LT |
407 | break; |
408 | } | |
409 | ||
4adbb6ac | 410 | pr_debug("Relocation became %lx\n", *ptr); |
13c3f50c | 411 | } |
1da177e4 LT |
412 | |
413 | /****************************************************************************/ | |
414 | ||
13c3f50c | 415 | static int load_flat_file(struct linux_binprm *bprm, |
1da177e4 LT |
416 | struct lib_info *libinfo, int id, unsigned long *extra_stack) |
417 | { | |
13c3f50c NP |
418 | struct flat_hdr *hdr; |
419 | unsigned long textpos, datapos, realdatastart; | |
420 | unsigned long text_len, data_len, bss_len, stack_len, full_data, flags; | |
421 | unsigned long len, memp, memp_size, extra, rlim; | |
422 | unsigned long *reloc, *rp; | |
1da177e4 | 423 | struct inode *inode; |
13c3f50c | 424 | int i, rev, relocs; |
1da177e4 LT |
425 | loff_t fpos; |
426 | unsigned long start_code, end_code; | |
13c3f50c | 427 | ssize_t result; |
1ad3dcc0 | 428 | int ret; |
1da177e4 LT |
429 | |
430 | hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */ | |
496ad9aa | 431 | inode = file_inode(bprm->file); |
1da177e4 LT |
432 | |
433 | text_len = ntohl(hdr->data_start); | |
434 | data_len = ntohl(hdr->data_end) - ntohl(hdr->data_start); | |
435 | bss_len = ntohl(hdr->bss_end) - ntohl(hdr->data_end); | |
436 | stack_len = ntohl(hdr->stack_size); | |
437 | if (extra_stack) { | |
438 | stack_len += *extra_stack; | |
439 | *extra_stack = stack_len; | |
440 | } | |
441 | relocs = ntohl(hdr->reloc_count); | |
442 | flags = ntohl(hdr->flags); | |
443 | rev = ntohl(hdr->rev); | |
3dc20cb2 | 444 | full_data = data_len + relocs * sizeof(unsigned long); |
1da177e4 | 445 | |
845884d3 | 446 | if (strncmp(hdr->magic, "bFLT", 4)) { |
1da177e4 | 447 | /* |
e2a366dc MF |
448 | * Previously, here was a printk to tell people |
449 | * "BINFMT_FLAT: bad header magic". | |
450 | * But for the kernel which also use ELF FD-PIC format, this | |
451 | * error message is confusing. | |
1da177e4 | 452 | * because a lot of people do not manage to produce good |
1da177e4 | 453 | */ |
1ad3dcc0 LY |
454 | ret = -ENOEXEC; |
455 | goto err; | |
845884d3 GU |
456 | } |
457 | ||
458 | if (flags & FLAT_FLAG_KTRACE) | |
4adbb6ac | 459 | pr_info("Loading file: %s\n", bprm->filename); |
845884d3 GU |
460 | |
461 | if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) { | |
4adbb6ac NP |
462 | pr_err("bad flat file version 0x%x (supported 0x%lx and 0x%lx)\n", |
463 | rev, FLAT_VERSION, OLD_FLAT_VERSION); | |
1ad3dcc0 LY |
464 | ret = -ENOEXEC; |
465 | goto err; | |
1da177e4 | 466 | } |
13c3f50c | 467 | |
1da177e4 LT |
468 | /* Don't allow old format executables to use shared libraries */ |
469 | if (rev == OLD_FLAT_VERSION && id != 0) { | |
4adbb6ac NP |
470 | pr_err("shared libraries are not available before rev 0x%lx\n", |
471 | FLAT_VERSION); | |
1ad3dcc0 LY |
472 | ret = -ENOEXEC; |
473 | goto err; | |
1da177e4 LT |
474 | } |
475 | ||
c995ee28 NP |
476 | /* |
477 | * Make sure the header params are sane. | |
478 | * 28 bits (256 MB) is way more than reasonable in this case. | |
479 | * If some top bits are set we have probable binary corruption. | |
480 | */ | |
481 | if ((text_len | data_len | bss_len | stack_len | full_data) >> 28) { | |
482 | pr_err("bad header\n"); | |
483 | ret = -ENOEXEC; | |
484 | goto err; | |
485 | } | |
486 | ||
1da177e4 LT |
487 | /* |
488 | * fix up the flags for the older format, there were all kinds | |
489 | * of endian hacks, this only works for the simple cases | |
490 | */ | |
491 | if (rev == OLD_FLAT_VERSION && flat_old_ram_flag(flags)) | |
492 | flags = FLAT_FLAG_RAM; | |
493 | ||
494 | #ifndef CONFIG_BINFMT_ZFLAT | |
495 | if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) { | |
4adbb6ac | 496 | pr_err("Support for ZFLAT executables is not enabled.\n"); |
1ad3dcc0 LY |
497 | ret = -ENOEXEC; |
498 | goto err; | |
1da177e4 LT |
499 | } |
500 | #endif | |
501 | ||
502 | /* | |
503 | * Check initial limits. This avoids letting people circumvent | |
504 | * size limits imposed on them by creating programs with large | |
505 | * arrays in the data or bss. | |
506 | */ | |
d554ed89 | 507 | rlim = rlimit(RLIMIT_DATA); |
1da177e4 LT |
508 | if (rlim >= RLIM_INFINITY) |
509 | rlim = ~0; | |
1ad3dcc0 LY |
510 | if (data_len + bss_len > rlim) { |
511 | ret = -ENOMEM; | |
512 | goto err; | |
513 | } | |
514 | ||
1da177e4 LT |
515 | /* Flush all traces of the currently running executable */ |
516 | if (id == 0) { | |
13c3f50c NP |
517 | ret = flush_old_exec(bprm); |
518 | if (ret) | |
df88912a | 519 | goto err; |
1da177e4 LT |
520 | |
521 | /* OK, This is the point of no return */ | |
fcc18e83 | 522 | set_personality(PER_LINUX_32BIT); |
221af7f8 | 523 | setup_new_exec(bprm); |
1da177e4 LT |
524 | } |
525 | ||
526 | /* | |
527 | * calculate the extra space we need to map in | |
528 | */ | |
0e647c04 AM |
529 | extra = max_t(unsigned long, bss_len + stack_len, |
530 | relocs * sizeof(unsigned long)); | |
1da177e4 LT |
531 | |
532 | /* | |
533 | * there are a couple of cases here, the separate code/data | |
534 | * case, and then the fully copied to RAM case which lumps | |
535 | * it all together. | |
536 | */ | |
537 | if ((flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP)) == 0) { | |
538 | /* | |
539 | * this should give us a ROM ptr, but if it doesn't we don't | |
540 | * really care | |
541 | */ | |
4adbb6ac | 542 | pr_debug("ROM mapping of file (we hope)\n"); |
1da177e4 | 543 | |
6be5ceb0 | 544 | textpos = vm_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC, |
925d1c40 | 545 | MAP_PRIVATE|MAP_EXECUTABLE, 0); |
0b8c78f2 | 546 | if (!textpos || IS_ERR_VALUE(textpos)) { |
1ad3dcc0 | 547 | ret = textpos; |
13c3f50c NP |
548 | if (!textpos) |
549 | ret = -ENOMEM; | |
4adbb6ac | 550 | pr_err("Unable to mmap process text, errno %d\n", ret); |
df88912a | 551 | goto err; |
1da177e4 LT |
552 | } |
553 | ||
72613e5f | 554 | len = data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long); |
0f3e442a | 555 | len = PAGE_ALIGN(len); |
13c3f50c | 556 | realdatastart = vm_mmap(NULL, 0, len, |
72613e5f | 557 | PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0); |
1da177e4 | 558 | |
0b8c78f2 | 559 | if (realdatastart == 0 || IS_ERR_VALUE(realdatastart)) { |
13c3f50c | 560 | ret = realdatastart; |
1da177e4 | 561 | if (!realdatastart) |
13c3f50c | 562 | ret = -ENOMEM; |
4adbb6ac | 563 | pr_err("Unable to allocate RAM for process data, " |
13c3f50c | 564 | "errno %d\n", ret); |
7696e0c3 | 565 | vm_munmap(textpos, text_len); |
df88912a | 566 | goto err; |
1da177e4 | 567 | } |
c3dc5bec OS |
568 | datapos = ALIGN(realdatastart + |
569 | MAX_SHARED_LIBS * sizeof(unsigned long), | |
570 | FLAT_DATA_ALIGN); | |
1da177e4 | 571 | |
4adbb6ac NP |
572 | pr_debug("Allocated data+bss+stack (%ld bytes): %lx\n", |
573 | data_len + bss_len + stack_len, datapos); | |
1da177e4 LT |
574 | |
575 | fpos = ntohl(hdr->data_start); | |
576 | #ifdef CONFIG_BINFMT_ZFLAT | |
577 | if (flags & FLAT_FLAG_GZDATA) { | |
13c3f50c | 578 | result = decompress_exec(bprm, fpos, (char *)datapos, |
3dc20cb2 | 579 | full_data, 0); |
1da177e4 LT |
580 | } else |
581 | #endif | |
582 | { | |
3dc20cb2 AV |
583 | result = read_code(bprm->file, datapos, fpos, |
584 | full_data); | |
1da177e4 | 585 | } |
0b8c78f2 | 586 | if (IS_ERR_VALUE(result)) { |
13c3f50c | 587 | ret = result; |
4adbb6ac | 588 | pr_err("Unable to read data+bss, errno %d\n", ret); |
7696e0c3 AV |
589 | vm_munmap(textpos, text_len); |
590 | vm_munmap(realdatastart, len); | |
df88912a | 591 | goto err; |
1da177e4 LT |
592 | } |
593 | ||
13c3f50c NP |
594 | reloc = (unsigned long *) |
595 | (datapos + (ntohl(hdr->reloc_start) - text_len)); | |
1da177e4 | 596 | memp = realdatastart; |
0f3e442a | 597 | memp_size = len; |
1da177e4 LT |
598 | } else { |
599 | ||
72613e5f | 600 | len = text_len + data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long); |
0f3e442a | 601 | len = PAGE_ALIGN(len); |
13c3f50c | 602 | textpos = vm_mmap(NULL, 0, len, |
72613e5f | 603 | PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0); |
72613e5f | 604 | |
0b8c78f2 | 605 | if (!textpos || IS_ERR_VALUE(textpos)) { |
1ad3dcc0 | 606 | ret = textpos; |
13c3f50c NP |
607 | if (!textpos) |
608 | ret = -ENOMEM; | |
4adbb6ac | 609 | pr_err("Unable to allocate RAM for process text/data, " |
13c3f50c | 610 | "errno %d\n", ret); |
df88912a | 611 | goto err; |
1da177e4 LT |
612 | } |
613 | ||
614 | realdatastart = textpos + ntohl(hdr->data_start); | |
c3dc5bec OS |
615 | datapos = ALIGN(realdatastart + |
616 | MAX_SHARED_LIBS * sizeof(unsigned long), | |
617 | FLAT_DATA_ALIGN); | |
618 | ||
619 | reloc = (unsigned long *) | |
620 | (datapos + (ntohl(hdr->reloc_start) - text_len)); | |
1da177e4 | 621 | memp = textpos; |
0f3e442a | 622 | memp_size = len; |
1da177e4 LT |
623 | #ifdef CONFIG_BINFMT_ZFLAT |
624 | /* | |
625 | * load it all in and treat it like a RAM load from now on | |
626 | */ | |
627 | if (flags & FLAT_FLAG_GZIP) { | |
13c3f50c NP |
628 | result = decompress_exec(bprm, sizeof(struct flat_hdr), |
629 | (((char *)textpos) + sizeof(struct flat_hdr)), | |
3dc20cb2 | 630 | (text_len + full_data |
13c3f50c | 631 | - sizeof(struct flat_hdr)), |
1da177e4 LT |
632 | 0); |
633 | memmove((void *) datapos, (void *) realdatastart, | |
3dc20cb2 | 634 | full_data); |
1da177e4 | 635 | } else if (flags & FLAT_FLAG_GZDATA) { |
3dc20cb2 | 636 | result = read_code(bprm->file, textpos, 0, text_len); |
0b8c78f2 | 637 | if (!IS_ERR_VALUE(result)) |
1da177e4 | 638 | result = decompress_exec(bprm, text_len, (char *) datapos, |
3dc20cb2 | 639 | full_data, 0); |
13c3f50c | 640 | } else |
1da177e4 LT |
641 | #endif |
642 | { | |
3dc20cb2 AV |
643 | result = read_code(bprm->file, textpos, 0, text_len); |
644 | if (!IS_ERR_VALUE(result)) | |
645 | result = read_code(bprm->file, datapos, | |
646 | ntohl(hdr->data_start), | |
647 | full_data); | |
1da177e4 | 648 | } |
0b8c78f2 | 649 | if (IS_ERR_VALUE(result)) { |
13c3f50c | 650 | ret = result; |
4adbb6ac | 651 | pr_err("Unable to read code+data+bss, errno %d\n", ret); |
7696e0c3 | 652 | vm_munmap(textpos, text_len + data_len + extra + |
1da177e4 | 653 | MAX_SHARED_LIBS * sizeof(unsigned long)); |
df88912a | 654 | goto err; |
1da177e4 LT |
655 | } |
656 | } | |
657 | ||
13c3f50c NP |
658 | start_code = textpos + sizeof(struct flat_hdr); |
659 | end_code = textpos + text_len; | |
660 | text_len -= sizeof(struct flat_hdr); /* the real code len */ | |
1da177e4 LT |
661 | |
662 | /* The main program needs a little extra setup in the task structure */ | |
1da177e4 LT |
663 | if (id == 0) { |
664 | current->mm->start_code = start_code; | |
665 | current->mm->end_code = end_code; | |
666 | current->mm->start_data = datapos; | |
667 | current->mm->end_data = datapos + data_len; | |
668 | /* | |
669 | * set up the brk stuff, uses any slack left in data/bss/stack | |
670 | * allocation. We put the brk after the bss (between the bss | |
671 | * and stack) like other platforms. | |
0f3e442a DH |
672 | * Userspace code relies on the stack pointer starting out at |
673 | * an address right at the end of a page. | |
1da177e4 LT |
674 | */ |
675 | current->mm->start_brk = datapos + data_len + bss_len; | |
676 | current->mm->brk = (current->mm->start_brk + 3) & ~3; | |
0f3e442a | 677 | current->mm->context.end_brk = memp + memp_size - stack_len; |
1da177e4 LT |
678 | } |
679 | ||
13c3f50c | 680 | if (flags & FLAT_FLAG_KTRACE) { |
4adbb6ac NP |
681 | pr_info("Mapping is %lx, Entry point is %x, data_start is %x\n", |
682 | textpos, 0x00ffffff&ntohl(hdr->entry), ntohl(hdr->data_start)); | |
683 | pr_info("%s %s: TEXT=%lx-%lx DATA=%lx-%lx BSS=%lx-%lx\n", | |
684 | id ? "Lib" : "Load", bprm->filename, | |
685 | start_code, end_code, datapos, datapos + data_len, | |
686 | datapos + data_len, (datapos + data_len + bss_len + 3) & ~3); | |
13c3f50c | 687 | } |
1da177e4 LT |
688 | |
689 | /* Store the current module values into the global library structure */ | |
690 | libinfo->lib_list[id].start_code = start_code; | |
691 | libinfo->lib_list[id].start_data = datapos; | |
692 | libinfo->lib_list[id].start_brk = datapos + data_len + bss_len; | |
693 | libinfo->lib_list[id].text_len = text_len; | |
694 | libinfo->lib_list[id].loaded = 1; | |
695 | libinfo->lib_list[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos; | |
696 | libinfo->lib_list[id].build_date = ntohl(hdr->build_date); | |
13c3f50c | 697 | |
1da177e4 LT |
698 | /* |
699 | * We just load the allocations into some temporary memory to | |
700 | * help simplify all this mumbo jumbo | |
701 | * | |
702 | * We've got two different sections of relocation entries. | |
25985edc | 703 | * The first is the GOT which resides at the beginning of the data segment |
1da177e4 LT |
704 | * and is terminated with a -1. This one can be relocated in place. |
705 | * The second is the extra relocation entries tacked after the image's | |
706 | * data segment. These require a little more processing as the entry is | |
707 | * really an offset into the image which contains an offset into the | |
708 | * image. | |
709 | */ | |
710 | if (flags & FLAT_FLAG_GOTPIC) { | |
711 | for (rp = (unsigned long *)datapos; *rp != 0xffffffff; rp++) { | |
712 | unsigned long addr; | |
713 | if (*rp) { | |
714 | addr = calc_reloc(*rp, libinfo, id, 0); | |
1ad3dcc0 LY |
715 | if (addr == RELOC_FAILED) { |
716 | ret = -ENOEXEC; | |
df88912a | 717 | goto err; |
1ad3dcc0 | 718 | } |
1da177e4 LT |
719 | *rp = addr; |
720 | } | |
721 | } | |
722 | } | |
723 | ||
724 | /* | |
725 | * Now run through the relocation entries. | |
726 | * We've got to be careful here as C++ produces relocatable zero | |
727 | * entries in the constructor and destructor tables which are then | |
728 | * tested for being not zero (which will always occur unless we're | |
729 | * based from address zero). This causes an endless loop as __start | |
730 | * is at zero. The solution used is to not relocate zero addresses. | |
731 | * This has the negative side effect of not allowing a global data | |
732 | * reference to be statically initialised to _stext (I've moved | |
733 | * __start to address 4 so that is okay). | |
734 | */ | |
735 | if (rev > OLD_FLAT_VERSION) { | |
f9720205 | 736 | unsigned long persistent = 0; |
13c3f50c | 737 | for (i = 0; i < relocs; i++) { |
1da177e4 LT |
738 | unsigned long addr, relval; |
739 | ||
13c3f50c NP |
740 | /* |
741 | * Get the address of the pointer to be | |
742 | * relocated (of course, the address has to be | |
743 | * relocated first). | |
744 | */ | |
1da177e4 | 745 | relval = ntohl(reloc[i]); |
13c3f50c | 746 | if (flat_set_persistent(relval, &persistent)) |
f9720205 | 747 | continue; |
1da177e4 LT |
748 | addr = flat_get_relocate_addr(relval); |
749 | rp = (unsigned long *) calc_reloc(addr, libinfo, id, 1); | |
1ad3dcc0 LY |
750 | if (rp == (unsigned long *)RELOC_FAILED) { |
751 | ret = -ENOEXEC; | |
df88912a | 752 | goto err; |
1ad3dcc0 | 753 | } |
1da177e4 LT |
754 | |
755 | /* Get the pointer's value. */ | |
576bb9ce AM |
756 | addr = flat_get_addr_from_rp(rp, relval, flags, |
757 | &persistent); | |
1da177e4 LT |
758 | if (addr != 0) { |
759 | /* | |
760 | * Do the relocation. PIC relocs in the data section are | |
761 | * already in target order | |
762 | */ | |
763 | if ((flags & FLAT_FLAG_GOTPIC) == 0) | |
764 | addr = ntohl(addr); | |
765 | addr = calc_reloc(addr, libinfo, id, 0); | |
1ad3dcc0 LY |
766 | if (addr == RELOC_FAILED) { |
767 | ret = -ENOEXEC; | |
df88912a | 768 | goto err; |
1ad3dcc0 | 769 | } |
1da177e4 LT |
770 | |
771 | /* Write back the relocated pointer. */ | |
772 | flat_put_addr_at_rp(rp, addr, relval); | |
773 | } | |
774 | } | |
775 | } else { | |
13c3f50c | 776 | for (i = 0; i < relocs; i++) |
1da177e4 LT |
777 | old_reloc(ntohl(reloc[i])); |
778 | } | |
13c3f50c | 779 | |
1da177e4 LT |
780 | flush_icache_range(start_code, end_code); |
781 | ||
782 | /* zero the BSS, BRK and stack areas */ | |
13c3f50c | 783 | memset((void *)(datapos + data_len), 0, bss_len + |
0f3e442a DH |
784 | (memp + memp_size - stack_len - /* end brk */ |
785 | libinfo->lib_list[id].start_brk) + /* start brk */ | |
1da177e4 LT |
786 | stack_len); |
787 | ||
788 | return 0; | |
1ad3dcc0 LY |
789 | err: |
790 | return ret; | |
1da177e4 LT |
791 | } |
792 | ||
793 | ||
794 | /****************************************************************************/ | |
795 | #ifdef CONFIG_BINFMT_SHARED_FLAT | |
796 | ||
797 | /* | |
798 | * Load a shared library into memory. The library gets its own data | |
799 | * segment (including bss) but not argv/argc/environ. | |
800 | */ | |
801 | ||
802 | static int load_flat_shared_library(int id, struct lib_info *libs) | |
803 | { | |
804 | struct linux_binprm bprm; | |
805 | int res; | |
806 | char buf[16]; | |
807 | ||
3a852d3b DH |
808 | memset(&bprm, 0, sizeof(bprm)); |
809 | ||
1da177e4 LT |
810 | /* Create the file name */ |
811 | sprintf(buf, "/lib/lib%d.so", id); | |
812 | ||
813 | /* Open the file up */ | |
814 | bprm.filename = buf; | |
815 | bprm.file = open_exec(bprm.filename); | |
816 | res = PTR_ERR(bprm.file); | |
817 | if (IS_ERR(bprm.file)) | |
818 | return res; | |
819 | ||
3440625d LT |
820 | bprm.cred = prepare_exec_creds(); |
821 | res = -ENOMEM; | |
822 | if (!bprm.cred) | |
823 | goto out; | |
824 | ||
3a852d3b DH |
825 | /* We don't really care about recalculating credentials at this point |
826 | * as we're past the point of no return and are dealing with shared | |
827 | * libraries. | |
828 | */ | |
829 | bprm.cred_prepared = 1; | |
830 | ||
1da177e4 LT |
831 | res = prepare_binprm(&bprm); |
832 | ||
287980e4 | 833 | if (!res) |
1da177e4 | 834 | res = load_flat_file(&bprm, libs, id, NULL); |
3440625d LT |
835 | |
836 | abort_creds(bprm.cred); | |
837 | ||
838 | out: | |
839 | allow_write_access(bprm.file); | |
840 | fput(bprm.file); | |
841 | ||
13c3f50c | 842 | return res; |
1da177e4 LT |
843 | } |
844 | ||
845 | #endif /* CONFIG_BINFMT_SHARED_FLAT */ | |
846 | /****************************************************************************/ | |
847 | ||
848 | /* | |
849 | * These are the functions used to load flat style executables and shared | |
850 | * libraries. There is no binary dependent code anywhere else. | |
851 | */ | |
852 | ||
13c3f50c | 853 | static int load_flat_binary(struct linux_binprm *bprm) |
1da177e4 LT |
854 | { |
855 | struct lib_info libinfo; | |
71613c3b | 856 | struct pt_regs *regs = current_pt_regs(); |
a97d157d | 857 | unsigned long stack_len; |
1da177e4 | 858 | unsigned long start_addr; |
1da177e4 LT |
859 | int res; |
860 | int i, j; | |
861 | ||
862 | memset(&libinfo, 0, sizeof(libinfo)); | |
13c3f50c | 863 | |
1da177e4 LT |
864 | /* |
865 | * We have to add the size of our arguments to our stack size | |
866 | * otherwise it's too easy for users to create stack overflows | |
867 | * by passing in a huge argument list. And yes, we have to be | |
868 | * pedantic and include space for the argv/envp array as it may have | |
869 | * a lot of entries. | |
870 | */ | |
a97d157d NP |
871 | stack_len = PAGE_SIZE * MAX_ARG_PAGES - bprm->p; /* the strings */ |
872 | stack_len += (bprm->argc + 1) * sizeof(char *); /* the argv array */ | |
873 | stack_len += (bprm->envc + 1) * sizeof(char *); /* the envp array */ | |
874 | stack_len = ALIGN(stack_len, FLAT_STACK_ALIGN); | |
13c3f50c | 875 | |
1da177e4 | 876 | res = load_flat_file(bprm, &libinfo, 0, &stack_len); |
287980e4 | 877 | if (res < 0) |
1da177e4 | 878 | return res; |
13c3f50c | 879 | |
1da177e4 | 880 | /* Update data segment pointers for all libraries */ |
13c3f50c | 881 | for (i = 0; i < MAX_SHARED_LIBS; i++) |
1da177e4 | 882 | if (libinfo.lib_list[i].loaded) |
13c3f50c | 883 | for (j = 0; j < MAX_SHARED_LIBS; j++) |
1da177e4 | 884 | (-(j+1))[(unsigned long *)(libinfo.lib_list[i].start_data)] = |
13c3f50c NP |
885 | (libinfo.lib_list[j].loaded) ? |
886 | libinfo.lib_list[j].start_data : UNLOADED_LIB; | |
1da177e4 | 887 | |
a6f76f23 | 888 | install_exec_creds(bprm); |
1da177e4 LT |
889 | |
890 | set_binfmt(&flat_format); | |
891 | ||
a97d157d NP |
892 | /* Stash our initial stack pointer into the mm structure */ |
893 | current->mm->start_stack = | |
894 | ((current->mm->context.end_brk + stack_len + 3) & ~3) - 4; | |
895 | pr_debug("sp=%lx\n", current->mm->start_stack); | |
1da177e4 | 896 | |
687fd773 | 897 | /* copy the arg pages onto the stack */ |
a97d157d NP |
898 | res = transfer_args_to_stack(bprm, ¤t->mm->start_stack); |
899 | if (!res) | |
900 | res = create_flat_tables(bprm, current->mm->start_stack); | |
687fd773 NP |
901 | if (res) |
902 | return res; | |
1da177e4 | 903 | |
1da177e4 LT |
904 | /* Fake some return addresses to ensure the call chain will |
905 | * initialise library in order for us. We are required to call | |
906 | * lib 1 first, then 2, ... and finally the main program (id 0). | |
907 | */ | |
908 | start_addr = libinfo.lib_list[0].entry; | |
909 | ||
910 | #ifdef CONFIG_BINFMT_SHARED_FLAT | |
13c3f50c | 911 | for (i = MAX_SHARED_LIBS-1; i > 0; i--) { |
1da177e4 LT |
912 | if (libinfo.lib_list[i].loaded) { |
913 | /* Push previos first to call address */ | |
a97d157d NP |
914 | unsigned long __user *sp; |
915 | current->mm->start_stack -= sizeof(unsigned long); | |
916 | sp = (unsigned long __user *)current->mm->start_stack; | |
917 | __put_user(start_addr, sp); | |
1da177e4 LT |
918 | start_addr = libinfo.lib_list[i].entry; |
919 | } | |
920 | } | |
921 | #endif | |
13c3f50c | 922 | |
74c27c43 TY |
923 | #ifdef FLAT_PLAT_INIT |
924 | FLAT_PLAT_INIT(regs); | |
925 | #endif | |
13c3f50c | 926 | |
4adbb6ac NP |
927 | pr_debug("start_thread(regs=0x%p, entry=0x%lx, start_stack=0x%lx)\n", |
928 | regs, start_addr, current->mm->start_stack); | |
1da177e4 LT |
929 | start_thread(regs, start_addr, current->mm->start_stack); |
930 | ||
1da177e4 LT |
931 | return 0; |
932 | } | |
933 | ||
934 | /****************************************************************************/ | |
935 | ||
936 | static int __init init_flat_binfmt(void) | |
937 | { | |
8fc3dc5a AV |
938 | register_binfmt(&flat_format); |
939 | return 0; | |
1da177e4 | 940 | } |
1da177e4 | 941 | core_initcall(init_flat_binfmt); |
1da177e4 LT |
942 | |
943 | /****************************************************************************/ |