blob: 9b2917a3029406f18ce2a0a0bbf62fdef7bca192 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/****************************************************************************/
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
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -040018#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
19
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#include <linux/kernel.h>
21#include <linux/sched.h>
22#include <linux/mm.h>
23#include <linux/mman.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include <linux/errno.h>
25#include <linux/signal.h>
26#include <linux/string.h>
27#include <linux/fs.h>
28#include <linux/file.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070029#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>
Nicolas Pitre13c3f502016-07-24 11:30:15 -040036#include <linux/uaccess.h>
Nicolas Pitre472f95f2016-07-24 11:30:26 -040037#include <linux/vmalloc.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070038
39#include <asm/byteorder.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070040#include <asm/unaligned.h>
41#include <asm/cacheflush.h>
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -070042#include <asm/page.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070043
44/****************************************************************************/
45
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -070046/*
Mike Frysinger2e94de82010-06-04 14:14:53 -070047 * User data (data section and bss) needs to be aligned.
48 * We pick 0x20 here because it is the max value elf2flt has always
49 * used in producing FLAT files, and because it seems to be large
50 * enough to make all the gcc alignment related tests happy.
51 */
52#define FLAT_DATA_ALIGN (0x20)
53
54/*
55 * User data (stack) also needs to be aligned.
56 * Here we can be a bit looser than the data sections since this
57 * needs to only meet arch ABI requirements.
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -070058 */
Mike Frysinger29520952010-06-29 15:05:21 -070059#define FLAT_STACK_ALIGN max_t(unsigned long, sizeof(void *), ARCH_SLAB_MINALIGN)
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -070060
Linus Torvalds1da177e2005-04-16 15:20:36 -070061#define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */
62#define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */
63
64struct lib_info {
65 struct {
66 unsigned long start_code; /* Start of text segment */
67 unsigned long start_data; /* Start of data segment */
68 unsigned long start_brk; /* End of data segment */
69 unsigned long text_len; /* Length of text segment */
70 unsigned long entry; /* Start address for this module */
71 unsigned long build_date; /* When this one was compiled */
Nicolas Pitre13c3f502016-07-24 11:30:15 -040072 bool loaded; /* Has this library been loaded? */
Linus Torvalds1da177e2005-04-16 15:20:36 -070073 } lib_list[MAX_SHARED_LIBS];
74};
75
76#ifdef CONFIG_BINFMT_SHARED_FLAT
77static int load_flat_shared_library(int id, struct lib_info *p);
78#endif
79
Al Viro71613c32012-10-20 22:00:48 -040080static int load_flat_binary(struct linux_binprm *);
Masami Hiramatsuf6151df2009-12-17 15:27:16 -080081static int flat_core_dump(struct coredump_params *cprm);
Linus Torvalds1da177e2005-04-16 15:20:36 -070082
Linus Torvalds1da177e2005-04-16 15:20:36 -070083static struct linux_binfmt flat_format = {
84 .module = THIS_MODULE,
85 .load_binary = load_flat_binary,
86 .core_dump = flat_core_dump,
87 .min_coredump = PAGE_SIZE
88};
89
90/****************************************************************************/
91/*
92 * Routine writes a core dump image in the current directory.
93 * Currently only a stub-function.
94 */
95
Masami Hiramatsuf6151df2009-12-17 15:27:16 -080096static int flat_core_dump(struct coredump_params *cprm)
Linus Torvalds1da177e2005-04-16 15:20:36 -070097{
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -040098 pr_warn("Process %s:%d received signr %d and should have core dumped\n",
99 current->comm, current->pid, cprm->siginfo->si_signo);
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400100 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101}
102
103/****************************************************************************/
104/*
105 * create_flat_tables() parses the env- and arg-strings in new user
106 * memory and creates the pointer tables from them, and puts their
Nicolas Pitrea97d1572016-07-24 11:30:20 -0400107 * addresses on the "stack", recording the new stack pointer value.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108 */
109
Nicolas Pitrea97d1572016-07-24 11:30:20 -0400110static int create_flat_tables(struct linux_binprm *bprm, unsigned long arg_start)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111{
Nicolas Pitrea97d1572016-07-24 11:30:20 -0400112 char __user *p;
113 unsigned long __user *sp;
114 long i, len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115
Nicolas Pitrea97d1572016-07-24 11:30:20 -0400116 p = (char __user *)arg_start;
117 sp = (unsigned long __user *)current->mm->start_stack;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118
Nicolas Pitrea97d1572016-07-24 11:30:20 -0400119 sp -= bprm->envc + 1;
120 sp -= bprm->argc + 1;
121 sp -= flat_argvp_envp_on_stack() ? 2 : 0;
122 sp -= 1; /* &argc */
123
124 current->mm->start_stack = (unsigned long)sp & -FLAT_STACK_ALIGN;
125 sp = (unsigned long __user *)current->mm->start_stack;
126
127 __put_user(bprm->argc, sp++);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128 if (flat_argvp_envp_on_stack()) {
Nicolas Pitrea97d1572016-07-24 11:30:20 -0400129 unsigned long argv, envp;
130 argv = (unsigned long)(sp + 2);
131 envp = (unsigned long)(sp + 2 + bprm->argc + 1);
132 __put_user(argv, sp++);
133 __put_user(envp, sp++);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134 }
135
Nicolas Pitrea97d1572016-07-24 11:30:20 -0400136 current->mm->arg_start = (unsigned long)p;
137 for (i = bprm->argc; i > 0; i--) {
138 __put_user((unsigned long)p, sp++);
139 len = strnlen_user(p, MAX_ARG_STRLEN);
140 if (!len || len > MAX_ARG_STRLEN)
141 return -EINVAL;
142 p += len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143 }
Nicolas Pitrea97d1572016-07-24 11:30:20 -0400144 __put_user(0, sp++);
145 current->mm->arg_end = (unsigned long)p;
146
147 current->mm->env_start = (unsigned long) p;
148 for (i = bprm->envc; i > 0; i--) {
149 __put_user((unsigned long)p, sp++);
150 len = strnlen_user(p, MAX_ARG_STRLEN);
151 if (!len || len > MAX_ARG_STRLEN)
152 return -EINVAL;
153 p += len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154 }
Nicolas Pitrea97d1572016-07-24 11:30:20 -0400155 __put_user(0, sp++);
156 current->mm->env_end = (unsigned long)p;
157
158 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159}
160
161/****************************************************************************/
162
163#ifdef CONFIG_BINFMT_ZFLAT
164
165#include <linux/zlib.h>
166
167#define LBUFSIZE 4000
168
169/* gzip flag byte */
170#define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */
171#define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
172#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
173#define ORIG_NAME 0x08 /* bit 3 set: original file name present */
174#define COMMENT 0x10 /* bit 4 set: file comment present */
175#define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */
176#define RESERVED 0xC0 /* bit 6,7: reserved */
177
178static int decompress_exec(
179 struct linux_binprm *bprm,
180 unsigned long offset,
181 char *dst,
182 long len,
183 int fd)
184{
185 unsigned char *buf;
186 z_stream strm;
187 loff_t fpos;
188 int ret, retval;
189
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400190 pr_debug("decompress_exec(offset=%lx,buf=%p,len=%lx)\n", offset, dst, len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191
192 memset(&strm, 0, sizeof(strm));
193 strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
194 if (strm.workspace == NULL) {
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400195 pr_debug("no memory for decompress workspace\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196 return -ENOMEM;
197 }
198 buf = kmalloc(LBUFSIZE, GFP_KERNEL);
199 if (buf == NULL) {
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400200 pr_debug("no memory for read buffer\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201 retval = -ENOMEM;
202 goto out_free;
203 }
204
205 /* Read in first chunk of data and parse gzip header. */
206 fpos = offset;
Al Viro3dc20cb2013-04-13 20:31:37 -0400207 ret = kernel_read(bprm->file, offset, buf, LBUFSIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208
209 strm.next_in = buf;
210 strm.avail_in = ret;
211 strm.total_in = 0;
Al Viro3dc20cb2013-04-13 20:31:37 -0400212 fpos += ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700213
214 retval = -ENOEXEC;
215
216 /* Check minimum size -- gzip header */
217 if (ret < 10) {
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400218 pr_debug("file too small?\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700219 goto out_free_buf;
220 }
221
222 /* Check gzip magic number */
223 if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) {
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400224 pr_debug("unknown compression magic?\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225 goto out_free_buf;
226 }
227
228 /* Check gzip method */
229 if (buf[2] != 8) {
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400230 pr_debug("unknown compression method?\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231 goto out_free_buf;
232 }
233 /* Check gzip flags */
234 if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) ||
235 (buf[3] & RESERVED)) {
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400236 pr_debug("unknown flags?\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237 goto out_free_buf;
238 }
239
240 ret = 10;
241 if (buf[3] & EXTRA_FIELD) {
242 ret += 2 + buf[10] + (buf[11] << 8);
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400243 if (unlikely(ret >= LBUFSIZE)) {
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400244 pr_debug("buffer overflow (EXTRA)?\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700245 goto out_free_buf;
246 }
247 }
248 if (buf[3] & ORIG_NAME) {
Volodymyr G. Lukiianykf4cfb182008-10-15 22:01:15 -0700249 while (ret < LBUFSIZE && buf[ret++] != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250 ;
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400251 if (unlikely(ret == LBUFSIZE)) {
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400252 pr_debug("buffer overflow (ORIG_NAME)?\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253 goto out_free_buf;
254 }
255 }
256 if (buf[3] & COMMENT) {
Volodymyr G. Lukiianykf4cfb182008-10-15 22:01:15 -0700257 while (ret < LBUFSIZE && buf[ret++] != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258 ;
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400259 if (unlikely(ret == LBUFSIZE)) {
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400260 pr_debug("buffer overflow (COMMENT)?\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261 goto out_free_buf;
262 }
263 }
264
265 strm.next_in += ret;
266 strm.avail_in -= ret;
267
268 strm.next_out = dst;
269 strm.avail_out = len;
270 strm.total_out = 0;
271
272 if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) {
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400273 pr_debug("zlib init failed?\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700274 goto out_free_buf;
275 }
276
277 while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) {
Al Viro3dc20cb2013-04-13 20:31:37 -0400278 ret = kernel_read(bprm->file, fpos, buf, LBUFSIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279 if (ret <= 0)
280 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281 len -= ret;
282
283 strm.next_in = buf;
284 strm.avail_in = ret;
285 strm.total_in = 0;
Al Viro3dc20cb2013-04-13 20:31:37 -0400286 fpos += ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287 }
288
289 if (ret < 0) {
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400290 pr_debug("decompression failed (%d), %s\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291 ret, strm.msg);
292 goto out_zlib;
293 }
294
295 retval = 0;
296out_zlib:
297 zlib_inflateEnd(&strm);
298out_free_buf:
299 kfree(buf);
300out_free:
301 kfree(strm.workspace);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302 return retval;
303}
304
305#endif /* CONFIG_BINFMT_ZFLAT */
306
307/****************************************************************************/
308
309static unsigned long
310calc_reloc(unsigned long r, struct lib_info *p, int curid, int internalp)
311{
312 unsigned long addr;
313 int id;
314 unsigned long start_brk;
315 unsigned long start_data;
316 unsigned long text_len;
317 unsigned long start_code;
318
319#ifdef CONFIG_BINFMT_SHARED_FLAT
320 if (r == 0)
321 id = curid; /* Relocs of 0 are always self referring */
322 else {
323 id = (r >> 24) & 0xff; /* Find ID for this reloc */
324 r &= 0x00ffffff; /* Trim ID off here */
325 }
326 if (id >= MAX_SHARED_LIBS) {
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400327 pr_err("reference 0x%lx to shared library %d", r, id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 goto failed;
329 }
330 if (curid != id) {
331 if (internalp) {
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400332 pr_err("reloc address 0x%lx not in same module "
333 "(%d != %d)", r, curid, id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334 goto failed;
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400335 } else if (!p->lib_list[id].loaded &&
336 load_flat_shared_library(id, p) < 0) {
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400337 pr_err("failed to load library %d", id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338 goto failed;
339 }
340 /* Check versioning information (i.e. time stamps) */
341 if (p->lib_list[id].build_date && p->lib_list[curid].build_date &&
342 p->lib_list[curid].build_date < p->lib_list[id].build_date) {
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400343 pr_err("library %d is younger than %d", id, curid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344 goto failed;
345 }
346 }
347#else
348 id = 0;
349#endif
350
351 start_brk = p->lib_list[id].start_brk;
352 start_data = p->lib_list[id].start_data;
353 start_code = p->lib_list[id].start_code;
354 text_len = p->lib_list[id].text_len;
355
356 if (!flat_reloc_valid(r, start_brk - start_data + text_len)) {
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400357 pr_err("reloc outside program 0x%lx (0 - 0x%lx/0x%lx)",
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400358 r, start_brk-start_data+text_len, text_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359 goto failed;
360 }
361
362 if (r < text_len) /* In text segment */
363 addr = r + start_code;
364 else /* In data segment */
365 addr = r - text_len + start_data;
366
367 /* Range checked already above so doing the range tests is redundant...*/
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400368 return addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700369
370failed:
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400371 pr_cont(", killing %s!\n", current->comm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700372 send_sig(SIGSEGV, current, 0);
373
374 return RELOC_FAILED;
375}
376
377/****************************************************************************/
378
Axel Lin34303432014-06-04 16:12:15 -0700379static void old_reloc(unsigned long rl)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380{
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400381 static const char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382 flat_v2_reloc_t r;
Nicolas Pitre1b2ce442016-07-24 11:30:22 -0400383 unsigned long __user *ptr;
384 unsigned long val;
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400385
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386 r.value = rl;
387#if defined(CONFIG_COLDFIRE)
Nicolas Pitre1b2ce442016-07-24 11:30:22 -0400388 ptr = (unsigned long __user *)(current->mm->start_code + r.reloc.offset);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389#else
Nicolas Pitre1b2ce442016-07-24 11:30:22 -0400390 ptr = (unsigned long __user *)(current->mm->start_data + r.reloc.offset);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391#endif
Nicolas Pitre1b2ce442016-07-24 11:30:22 -0400392 get_user(val, ptr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400394 pr_debug("Relocation of variable at DATASEG+%x "
395 "(address %p, currently %lx) into segment %s\n",
Nicolas Pitre1b2ce442016-07-24 11:30:22 -0400396 r.reloc.offset, ptr, val, segment[r.reloc.type]);
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400397
Linus Torvalds1da177e2005-04-16 15:20:36 -0700398 switch (r.reloc.type) {
399 case OLD_FLAT_RELOC_TYPE_TEXT:
Nicolas Pitre1b2ce442016-07-24 11:30:22 -0400400 val += current->mm->start_code;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700401 break;
402 case OLD_FLAT_RELOC_TYPE_DATA:
Nicolas Pitre1b2ce442016-07-24 11:30:22 -0400403 val += current->mm->start_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700404 break;
405 case OLD_FLAT_RELOC_TYPE_BSS:
Nicolas Pitre1b2ce442016-07-24 11:30:22 -0400406 val += current->mm->end_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407 break;
408 default:
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400409 pr_err("Unknown relocation type=%x\n", r.reloc.type);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410 break;
411 }
Nicolas Pitre1b2ce442016-07-24 11:30:22 -0400412 put_user(val, ptr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700413
Nicolas Pitre1b2ce442016-07-24 11:30:22 -0400414 pr_debug("Relocation became %lx\n", val);
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400415}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700416
417/****************************************************************************/
418
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400419static int load_flat_file(struct linux_binprm *bprm,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700420 struct lib_info *libinfo, int id, unsigned long *extra_stack)
421{
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400422 struct flat_hdr *hdr;
423 unsigned long textpos, datapos, realdatastart;
424 unsigned long text_len, data_len, bss_len, stack_len, full_data, flags;
425 unsigned long len, memp, memp_size, extra, rlim;
Nicolas Pitre6e572ff2016-07-24 11:30:21 -0400426 unsigned long __user *reloc, *rp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700427 struct inode *inode;
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400428 int i, rev, relocs;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700429 loff_t fpos;
430 unsigned long start_code, end_code;
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400431 ssize_t result;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800432 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433
434 hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */
Al Viro496ad9a2013-01-23 17:07:38 -0500435 inode = file_inode(bprm->file);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436
437 text_len = ntohl(hdr->data_start);
438 data_len = ntohl(hdr->data_end) - ntohl(hdr->data_start);
439 bss_len = ntohl(hdr->bss_end) - ntohl(hdr->data_end);
440 stack_len = ntohl(hdr->stack_size);
441 if (extra_stack) {
442 stack_len += *extra_stack;
443 *extra_stack = stack_len;
444 }
445 relocs = ntohl(hdr->reloc_count);
446 flags = ntohl(hdr->flags);
447 rev = ntohl(hdr->rev);
Al Viro3dc20cb2013-04-13 20:31:37 -0400448 full_data = data_len + relocs * sizeof(unsigned long);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700449
Greg Ungerer845884d2006-01-10 16:59:37 +1000450 if (strncmp(hdr->magic, "bFLT", 4)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451 /*
Mike Frysingere2a366d2008-02-14 19:31:29 -0800452 * Previously, here was a printk to tell people
453 * "BINFMT_FLAT: bad header magic".
454 * But for the kernel which also use ELF FD-PIC format, this
455 * error message is confusing.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700456 * because a lot of people do not manage to produce good
Linus Torvalds1da177e2005-04-16 15:20:36 -0700457 */
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800458 ret = -ENOEXEC;
459 goto err;
Greg Ungerer845884d2006-01-10 16:59:37 +1000460 }
461
462 if (flags & FLAT_FLAG_KTRACE)
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400463 pr_info("Loading file: %s\n", bprm->filename);
Greg Ungerer845884d2006-01-10 16:59:37 +1000464
465 if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) {
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400466 pr_err("bad flat file version 0x%x (supported 0x%lx and 0x%lx)\n",
467 rev, FLAT_VERSION, OLD_FLAT_VERSION);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800468 ret = -ENOEXEC;
469 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700470 }
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400471
Linus Torvalds1da177e2005-04-16 15:20:36 -0700472 /* Don't allow old format executables to use shared libraries */
473 if (rev == OLD_FLAT_VERSION && id != 0) {
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400474 pr_err("shared libraries are not available before rev 0x%lx\n",
475 FLAT_VERSION);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800476 ret = -ENOEXEC;
477 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700478 }
479
480 /*
Nicolas Pitrec995ee22016-07-24 11:30:17 -0400481 * Make sure the header params are sane.
482 * 28 bits (256 MB) is way more than reasonable in this case.
483 * If some top bits are set we have probable binary corruption.
484 */
485 if ((text_len | data_len | bss_len | stack_len | full_data) >> 28) {
486 pr_err("bad header\n");
487 ret = -ENOEXEC;
488 goto err;
489 }
490
491 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700492 * fix up the flags for the older format, there were all kinds
493 * of endian hacks, this only works for the simple cases
494 */
495 if (rev == OLD_FLAT_VERSION && flat_old_ram_flag(flags))
496 flags = FLAT_FLAG_RAM;
497
498#ifndef CONFIG_BINFMT_ZFLAT
499 if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) {
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400500 pr_err("Support for ZFLAT executables is not enabled.\n");
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800501 ret = -ENOEXEC;
502 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700503 }
504#endif
505
506 /*
507 * Check initial limits. This avoids letting people circumvent
508 * size limits imposed on them by creating programs with large
509 * arrays in the data or bss.
510 */
Jiri Slabyd554ed892010-03-05 13:42:42 -0800511 rlim = rlimit(RLIMIT_DATA);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700512 if (rlim >= RLIM_INFINITY)
513 rlim = ~0;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800514 if (data_len + bss_len > rlim) {
515 ret = -ENOMEM;
516 goto err;
517 }
518
Linus Torvalds1da177e2005-04-16 15:20:36 -0700519 /* Flush all traces of the currently running executable */
520 if (id == 0) {
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400521 ret = flush_old_exec(bprm);
522 if (ret)
Andrew Mortondf889122006-05-20 15:00:01 -0700523 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524
525 /* OK, This is the point of no return */
Malcolm Parsonsfcc18e82006-06-26 11:49:41 +1000526 set_personality(PER_LINUX_32BIT);
Linus Torvalds221af7f2010-01-28 22:14:42 -0800527 setup_new_exec(bprm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700528 }
529
530 /*
531 * calculate the extra space we need to map in
532 */
Andrew Morton0e647c02007-10-16 23:27:26 -0700533 extra = max_t(unsigned long, bss_len + stack_len,
534 relocs * sizeof(unsigned long));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700535
536 /*
537 * there are a couple of cases here, the separate code/data
538 * case, and then the fully copied to RAM case which lumps
539 * it all together.
540 */
Nicolas Pitre015feac2016-07-24 11:30:25 -0400541 if (!IS_ENABLED(CONFIG_MMU) && !(flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542 /*
543 * this should give us a ROM ptr, but if it doesn't we don't
544 * really care
545 */
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400546 pr_debug("ROM mapping of file (we hope)\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700547
Linus Torvalds6be5ceb2012-04-20 17:13:58 -0700548 textpos = vm_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC,
Matt Helsley925d1c42008-04-29 01:01:36 -0700549 MAP_PRIVATE|MAP_EXECUTABLE, 0);
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700550 if (!textpos || IS_ERR_VALUE(textpos)) {
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800551 ret = textpos;
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400552 if (!textpos)
553 ret = -ENOMEM;
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400554 pr_err("Unable to mmap process text, errno %d\n", ret);
Andrew Mortondf889122006-05-20 15:00:01 -0700555 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556 }
557
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000558 len = data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
David Howells0f3e4422009-01-08 12:04:47 +0000559 len = PAGE_ALIGN(len);
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400560 realdatastart = vm_mmap(NULL, 0, len,
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000561 PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700562
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700563 if (realdatastart == 0 || IS_ERR_VALUE(realdatastart)) {
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800564 ret = realdatastart;
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400565 if (!realdatastart)
566 ret = -ENOMEM;
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400567 pr_err("Unable to allocate RAM for process data, "
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400568 "errno %d\n", ret);
569 vm_munmap(textpos, text_len);
Andrew Mortondf889122006-05-20 15:00:01 -0700570 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700571 }
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -0700572 datapos = ALIGN(realdatastart +
573 MAX_SHARED_LIBS * sizeof(unsigned long),
574 FLAT_DATA_ALIGN);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700575
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400576 pr_debug("Allocated data+bss+stack (%ld bytes): %lx\n",
577 data_len + bss_len + stack_len, datapos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700578
579 fpos = ntohl(hdr->data_start);
580#ifdef CONFIG_BINFMT_ZFLAT
581 if (flags & FLAT_FLAG_GZDATA) {
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400582 result = decompress_exec(bprm, fpos, (char *)datapos,
Al Viro3dc20cb2013-04-13 20:31:37 -0400583 full_data, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584 } else
585#endif
586 {
Al Viro3dc20cb2013-04-13 20:31:37 -0400587 result = read_code(bprm->file, datapos, fpos,
588 full_data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589 }
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700590 if (IS_ERR_VALUE(result)) {
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400591 ret = result;
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400592 pr_err("Unable to read data+bss, errno %d\n", ret);
Al Viro7696e0c2012-05-30 01:56:23 -0400593 vm_munmap(textpos, text_len);
594 vm_munmap(realdatastart, len);
Andrew Mortondf889122006-05-20 15:00:01 -0700595 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596 }
597
Nicolas Pitre6e572ff2016-07-24 11:30:21 -0400598 reloc = (unsigned long __user *)
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400599 (datapos + (ntohl(hdr->reloc_start) - text_len));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700600 memp = realdatastart;
David Howells0f3e4422009-01-08 12:04:47 +0000601 memp_size = len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602 } else {
603
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000604 len = text_len + data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
David Howells0f3e4422009-01-08 12:04:47 +0000605 len = PAGE_ALIGN(len);
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400606 textpos = vm_mmap(NULL, 0, len,
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000607 PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0);
Greg Ungerer72613e5f2007-02-07 12:03:08 +1000608
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700609 if (!textpos || IS_ERR_VALUE(textpos)) {
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800610 ret = textpos;
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400611 if (!textpos)
612 ret = -ENOMEM;
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400613 pr_err("Unable to allocate RAM for process text/data, "
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400614 "errno %d\n", ret);
Andrew Mortondf889122006-05-20 15:00:01 -0700615 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616 }
617
618 realdatastart = textpos + ntohl(hdr->data_start);
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -0700619 datapos = ALIGN(realdatastart +
620 MAX_SHARED_LIBS * sizeof(unsigned long),
621 FLAT_DATA_ALIGN);
622
Nicolas Pitre6e572ff2016-07-24 11:30:21 -0400623 reloc = (unsigned long __user *)
Oskar Schirmerc3dc5be2009-05-28 14:34:31 -0700624 (datapos + (ntohl(hdr->reloc_start) - text_len));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625 memp = textpos;
David Howells0f3e4422009-01-08 12:04:47 +0000626 memp_size = len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700627#ifdef CONFIG_BINFMT_ZFLAT
628 /*
629 * load it all in and treat it like a RAM load from now on
630 */
631 if (flags & FLAT_FLAG_GZIP) {
Nicolas Pitre472f95f2016-07-24 11:30:26 -0400632#ifndef CONFIG_MMU
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400633 result = decompress_exec(bprm, sizeof(struct flat_hdr),
634 (((char *)textpos) + sizeof(struct flat_hdr)),
Al Viro3dc20cb2013-04-13 20:31:37 -0400635 (text_len + full_data
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400636 - sizeof(struct flat_hdr)),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637 0);
638 memmove((void *) datapos, (void *) realdatastart,
Al Viro3dc20cb2013-04-13 20:31:37 -0400639 full_data);
Nicolas Pitre472f95f2016-07-24 11:30:26 -0400640#else
641 /*
642 * This is used on MMU systems mainly for testing.
643 * Let's use a kernel buffer to simplify things.
644 */
645 long unz_text_len = text_len - sizeof(struct flat_hdr);
646 long unz_len = unz_text_len + full_data;
647 char *unz_data = vmalloc(unz_len);
648 if (!unz_data) {
649 result = -ENOMEM;
650 } else {
651 result = decompress_exec(bprm, sizeof(struct flat_hdr),
652 unz_data, unz_len, 0);
653 if (result == 0 &&
654 (copy_to_user((void __user *)textpos + sizeof(struct flat_hdr),
655 unz_data, unz_text_len) ||
656 copy_to_user((void __user *)datapos,
657 unz_data + unz_text_len, full_data)))
658 result = -EFAULT;
659 vfree(unz_data);
660 }
661#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700662 } else if (flags & FLAT_FLAG_GZDATA) {
Al Viro3dc20cb2013-04-13 20:31:37 -0400663 result = read_code(bprm->file, textpos, 0, text_len);
Nicolas Pitre472f95f2016-07-24 11:30:26 -0400664 if (!IS_ERR_VALUE(result)) {
665#ifndef CONFIG_MMU
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666 result = decompress_exec(bprm, text_len, (char *) datapos,
Al Viro3dc20cb2013-04-13 20:31:37 -0400667 full_data, 0);
Nicolas Pitre472f95f2016-07-24 11:30:26 -0400668#else
669 char *unz_data = vmalloc(full_data);
670 if (!unz_data) {
671 result = -ENOMEM;
672 } else {
673 result = decompress_exec(bprm, text_len,
674 unz_data, full_data, 0);
675 if (result == 0 &&
676 copy_to_user((void __user *)datapos,
677 unz_data, full_data))
678 result = -EFAULT;
679 vfree(unz_data);
680 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700681#endif
Nicolas Pitre472f95f2016-07-24 11:30:26 -0400682 }
683 } else
684#endif /* CONFIG_BINFMT_ZFLAT */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700685 {
Al Viro3dc20cb2013-04-13 20:31:37 -0400686 result = read_code(bprm->file, textpos, 0, text_len);
687 if (!IS_ERR_VALUE(result))
688 result = read_code(bprm->file, datapos,
689 ntohl(hdr->data_start),
690 full_data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700691 }
Mike Frysinger0b8c78f2009-09-23 15:57:07 -0700692 if (IS_ERR_VALUE(result)) {
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400693 ret = result;
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400694 pr_err("Unable to read code+data+bss, errno %d\n", ret);
Al Viro7696e0c2012-05-30 01:56:23 -0400695 vm_munmap(textpos, text_len + data_len + extra +
Linus Torvalds1da177e2005-04-16 15:20:36 -0700696 MAX_SHARED_LIBS * sizeof(unsigned long));
Andrew Mortondf889122006-05-20 15:00:01 -0700697 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700698 }
699 }
700
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400701 start_code = textpos + sizeof(struct flat_hdr);
702 end_code = textpos + text_len;
703 text_len -= sizeof(struct flat_hdr); /* the real code len */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700704
705 /* The main program needs a little extra setup in the task structure */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700706 if (id == 0) {
707 current->mm->start_code = start_code;
708 current->mm->end_code = end_code;
709 current->mm->start_data = datapos;
710 current->mm->end_data = datapos + data_len;
711 /*
712 * set up the brk stuff, uses any slack left in data/bss/stack
713 * allocation. We put the brk after the bss (between the bss
714 * and stack) like other platforms.
David Howells0f3e4422009-01-08 12:04:47 +0000715 * Userspace code relies on the stack pointer starting out at
716 * an address right at the end of a page.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700717 */
718 current->mm->start_brk = datapos + data_len + bss_len;
719 current->mm->brk = (current->mm->start_brk + 3) & ~3;
Nicolas Pitre015feac2016-07-24 11:30:25 -0400720#ifndef CONFIG_MMU
David Howells0f3e4422009-01-08 12:04:47 +0000721 current->mm->context.end_brk = memp + memp_size - stack_len;
Nicolas Pitre015feac2016-07-24 11:30:25 -0400722#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700723 }
724
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400725 if (flags & FLAT_FLAG_KTRACE) {
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -0400726 pr_info("Mapping is %lx, Entry point is %x, data_start is %x\n",
727 textpos, 0x00ffffff&ntohl(hdr->entry), ntohl(hdr->data_start));
728 pr_info("%s %s: TEXT=%lx-%lx DATA=%lx-%lx BSS=%lx-%lx\n",
729 id ? "Lib" : "Load", bprm->filename,
730 start_code, end_code, datapos, datapos + data_len,
731 datapos + data_len, (datapos + data_len + bss_len + 3) & ~3);
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400732 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700733
734 /* Store the current module values into the global library structure */
735 libinfo->lib_list[id].start_code = start_code;
736 libinfo->lib_list[id].start_data = datapos;
737 libinfo->lib_list[id].start_brk = datapos + data_len + bss_len;
738 libinfo->lib_list[id].text_len = text_len;
739 libinfo->lib_list[id].loaded = 1;
740 libinfo->lib_list[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos;
741 libinfo->lib_list[id].build_date = ntohl(hdr->build_date);
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400742
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743 /*
744 * We just load the allocations into some temporary memory to
745 * help simplify all this mumbo jumbo
746 *
747 * We've got two different sections of relocation entries.
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300748 * The first is the GOT which resides at the beginning of the data segment
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749 * and is terminated with a -1. This one can be relocated in place.
750 * The second is the extra relocation entries tacked after the image's
751 * data segment. These require a little more processing as the entry is
752 * really an offset into the image which contains an offset into the
753 * image.
754 */
755 if (flags & FLAT_FLAG_GOTPIC) {
Nicolas Pitre6e572ff2016-07-24 11:30:21 -0400756 for (rp = (unsigned long __user *)datapos; ; rp++) {
757 unsigned long addr, rp_val;
758 if (get_user(rp_val, rp))
759 return -EFAULT;
760 if (rp_val == 0xffffffff)
761 break;
762 if (rp_val) {
763 addr = calc_reloc(rp_val, libinfo, id, 0);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800764 if (addr == RELOC_FAILED) {
765 ret = -ENOEXEC;
Andrew Mortondf889122006-05-20 15:00:01 -0700766 goto err;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800767 }
Nicolas Pitre6e572ff2016-07-24 11:30:21 -0400768 if (put_user(addr, rp))
769 return -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700770 }
771 }
772 }
773
774 /*
775 * Now run through the relocation entries.
776 * We've got to be careful here as C++ produces relocatable zero
777 * entries in the constructor and destructor tables which are then
778 * tested for being not zero (which will always occur unless we're
779 * based from address zero). This causes an endless loop as __start
780 * is at zero. The solution used is to not relocate zero addresses.
781 * This has the negative side effect of not allowing a global data
782 * reference to be statically initialised to _stext (I've moved
783 * __start to address 4 so that is okay).
784 */
785 if (rev > OLD_FLAT_VERSION) {
Nicolas Pitre6e572ff2016-07-24 11:30:21 -0400786 unsigned long __maybe_unused persistent = 0;
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400787 for (i = 0; i < relocs; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700788 unsigned long addr, relval;
789
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400790 /*
791 * Get the address of the pointer to be
792 * relocated (of course, the address has to be
793 * relocated first).
794 */
Nicolas Pitre6e572ff2016-07-24 11:30:21 -0400795 if (get_user(relval, reloc + i))
796 return -EFAULT;
797 relval = ntohl(relval);
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400798 if (flat_set_persistent(relval, &persistent))
Bernd Schmidtf9720202007-10-03 23:41:43 +0800799 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700800 addr = flat_get_relocate_addr(relval);
Nicolas Pitre6e572ff2016-07-24 11:30:21 -0400801 rp = (unsigned long __user *)calc_reloc(addr, libinfo, id, 1);
802 if (rp == (unsigned long __user *)RELOC_FAILED) {
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800803 ret = -ENOEXEC;
Andrew Mortondf889122006-05-20 15:00:01 -0700804 goto err;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800805 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700806
807 /* Get the pointer's value. */
Andrew Morton576bb9c2007-10-03 23:43:57 +0800808 addr = flat_get_addr_from_rp(rp, relval, flags,
809 &persistent);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700810 if (addr != 0) {
811 /*
812 * Do the relocation. PIC relocs in the data section are
813 * already in target order
814 */
815 if ((flags & FLAT_FLAG_GOTPIC) == 0)
816 addr = ntohl(addr);
817 addr = calc_reloc(addr, libinfo, id, 0);
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800818 if (addr == RELOC_FAILED) {
819 ret = -ENOEXEC;
Andrew Mortondf889122006-05-20 15:00:01 -0700820 goto err;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800821 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700822
823 /* Write back the relocated pointer. */
824 flat_put_addr_at_rp(rp, addr, relval);
825 }
826 }
827 } else {
Nicolas Pitre1b2ce442016-07-24 11:30:22 -0400828 for (i = 0; i < relocs; i++) {
829 unsigned long relval;
830 if (get_user(relval, reloc + i))
831 return -EFAULT;
832 relval = ntohl(relval);
833 old_reloc(relval);
834 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700835 }
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400836
Linus Torvalds1da177e2005-04-16 15:20:36 -0700837 flush_icache_range(start_code, end_code);
838
839 /* zero the BSS, BRK and stack areas */
Nicolas Pitre467aa142016-07-24 11:30:23 -0400840 if (clear_user((void __user *)(datapos + data_len), bss_len +
841 (memp + memp_size - stack_len - /* end brk */
842 libinfo->lib_list[id].start_brk) + /* start brk */
843 stack_len))
844 return -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700845
846 return 0;
Luke Yang1ad3dcc2006-03-25 03:08:24 -0800847err:
848 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700849}
850
851
852/****************************************************************************/
853#ifdef CONFIG_BINFMT_SHARED_FLAT
854
855/*
856 * Load a shared library into memory. The library gets its own data
857 * segment (including bss) but not argv/argc/environ.
858 */
859
860static int load_flat_shared_library(int id, struct lib_info *libs)
861{
862 struct linux_binprm bprm;
863 int res;
864 char buf[16];
865
David Howells3a852d32011-04-28 16:26:38 +0100866 memset(&bprm, 0, sizeof(bprm));
867
Linus Torvalds1da177e2005-04-16 15:20:36 -0700868 /* Create the file name */
869 sprintf(buf, "/lib/lib%d.so", id);
870
871 /* Open the file up */
872 bprm.filename = buf;
873 bprm.file = open_exec(bprm.filename);
874 res = PTR_ERR(bprm.file);
875 if (IS_ERR(bprm.file))
876 return res;
877
Linus Torvalds34406252009-08-06 15:09:34 -0700878 bprm.cred = prepare_exec_creds();
879 res = -ENOMEM;
880 if (!bprm.cred)
881 goto out;
882
David Howells3a852d32011-04-28 16:26:38 +0100883 /* We don't really care about recalculating credentials at this point
884 * as we're past the point of no return and are dealing with shared
885 * libraries.
886 */
887 bprm.cred_prepared = 1;
888
Linus Torvalds1da177e2005-04-16 15:20:36 -0700889 res = prepare_binprm(&bprm);
890
Arnd Bergmann287980e2016-05-27 23:23:25 +0200891 if (!res)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700892 res = load_flat_file(&bprm, libs, id, NULL);
Linus Torvalds34406252009-08-06 15:09:34 -0700893
894 abort_creds(bprm.cred);
895
896out:
897 allow_write_access(bprm.file);
898 fput(bprm.file);
899
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400900 return res;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700901}
902
903#endif /* CONFIG_BINFMT_SHARED_FLAT */
904/****************************************************************************/
905
906/*
907 * These are the functions used to load flat style executables and shared
908 * libraries. There is no binary dependent code anywhere else.
909 */
910
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400911static int load_flat_binary(struct linux_binprm *bprm)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700912{
913 struct lib_info libinfo;
Al Viro71613c32012-10-20 22:00:48 -0400914 struct pt_regs *regs = current_pt_regs();
Nicolas Pitre015feac2016-07-24 11:30:25 -0400915 unsigned long stack_len = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700916 unsigned long start_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700917 int res;
918 int i, j;
919
920 memset(&libinfo, 0, sizeof(libinfo));
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400921
Linus Torvalds1da177e2005-04-16 15:20:36 -0700922 /*
923 * We have to add the size of our arguments to our stack size
924 * otherwise it's too easy for users to create stack overflows
925 * by passing in a huge argument list. And yes, we have to be
926 * pedantic and include space for the argv/envp array as it may have
927 * a lot of entries.
928 */
Nicolas Pitre015feac2016-07-24 11:30:25 -0400929#ifndef CONFIG_MMU
930 stack_len += PAGE_SIZE * MAX_ARG_PAGES - bprm->p; /* the strings */
931#endif
Nicolas Pitrea97d1572016-07-24 11:30:20 -0400932 stack_len += (bprm->argc + 1) * sizeof(char *); /* the argv array */
933 stack_len += (bprm->envc + 1) * sizeof(char *); /* the envp array */
934 stack_len = ALIGN(stack_len, FLAT_STACK_ALIGN);
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400935
Linus Torvalds1da177e2005-04-16 15:20:36 -0700936 res = load_flat_file(bprm, &libinfo, 0, &stack_len);
Arnd Bergmann287980e2016-05-27 23:23:25 +0200937 if (res < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700938 return res;
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400939
Linus Torvalds1da177e2005-04-16 15:20:36 -0700940 /* Update data segment pointers for all libraries */
Nicolas Pitreaf521f92016-07-24 11:30:24 -0400941 for (i = 0; i < MAX_SHARED_LIBS; i++) {
942 if (!libinfo.lib_list[i].loaded)
943 continue;
944 for (j = 0; j < MAX_SHARED_LIBS; j++) {
945 unsigned long val = libinfo.lib_list[j].loaded ?
946 libinfo.lib_list[j].start_data : UNLOADED_LIB;
947 unsigned long __user *p = (unsigned long __user *)
948 libinfo.lib_list[i].start_data;
949 p -= j + 1;
950 if (put_user(val, p))
951 return -EFAULT;
952 }
953 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700954
David Howellsa6f76f22008-11-14 10:39:24 +1100955 install_exec_creds(bprm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700956
957 set_binfmt(&flat_format);
958
Nicolas Pitre015feac2016-07-24 11:30:25 -0400959#ifdef CONFIG_MMU
960 res = setup_arg_pages(bprm, STACK_TOP, EXSTACK_DEFAULT);
961 if (!res)
962 res = create_flat_tables(bprm, bprm->p);
963#else
Nicolas Pitrea97d1572016-07-24 11:30:20 -0400964 /* Stash our initial stack pointer into the mm structure */
965 current->mm->start_stack =
966 ((current->mm->context.end_brk + stack_len + 3) & ~3) - 4;
967 pr_debug("sp=%lx\n", current->mm->start_stack);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700968
Nicolas Pitre687fd772016-07-24 11:30:19 -0400969 /* copy the arg pages onto the stack */
Nicolas Pitrea97d1572016-07-24 11:30:20 -0400970 res = transfer_args_to_stack(bprm, &current->mm->start_stack);
971 if (!res)
972 res = create_flat_tables(bprm, current->mm->start_stack);
Nicolas Pitre015feac2016-07-24 11:30:25 -0400973#endif
Nicolas Pitre687fd772016-07-24 11:30:19 -0400974 if (res)
975 return res;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700976
Linus Torvalds1da177e2005-04-16 15:20:36 -0700977 /* Fake some return addresses to ensure the call chain will
978 * initialise library in order for us. We are required to call
979 * lib 1 first, then 2, ... and finally the main program (id 0).
980 */
981 start_addr = libinfo.lib_list[0].entry;
982
983#ifdef CONFIG_BINFMT_SHARED_FLAT
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400984 for (i = MAX_SHARED_LIBS-1; i > 0; i--) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700985 if (libinfo.lib_list[i].loaded) {
986 /* Push previos first to call address */
Nicolas Pitrea97d1572016-07-24 11:30:20 -0400987 unsigned long __user *sp;
988 current->mm->start_stack -= sizeof(unsigned long);
989 sp = (unsigned long __user *)current->mm->start_stack;
990 __put_user(start_addr, sp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700991 start_addr = libinfo.lib_list[i].entry;
992 }
993 }
994#endif
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400995
Takashi YOSHII74c27c42008-08-11 20:10:54 +0900996#ifdef FLAT_PLAT_INIT
997 FLAT_PLAT_INIT(regs);
998#endif
Nicolas Pitre13c3f502016-07-24 11:30:15 -0400999
Nicolas Pitre4adbb6a2016-07-24 11:30:16 -04001000 pr_debug("start_thread(regs=0x%p, entry=0x%lx, start_stack=0x%lx)\n",
1001 regs, start_addr, current->mm->start_stack);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001002 start_thread(regs, start_addr, current->mm->start_stack);
1003
Linus Torvalds1da177e2005-04-16 15:20:36 -07001004 return 0;
1005}
1006
1007/****************************************************************************/
1008
1009static int __init init_flat_binfmt(void)
1010{
Al Viro8fc3dc52012-03-17 03:05:16 -04001011 register_binfmt(&flat_format);
1012 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001013}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001014core_initcall(init_flat_binfmt);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001015
1016/****************************************************************************/