1 /****************************************************************************/
3 * linux/fs/binfmt_flat.c
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>
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)
18 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
20 #include <linux/kernel.h>
21 #include <linux/sched.h>
23 #include <linux/mman.h>
24 #include <linux/errno.h>
25 #include <linux/signal.h>
26 #include <linux/string.h>
28 #include <linux/file.h>
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>
36 #include <linux/uaccess.h>
38 #include <asm/byteorder.h>
39 #include <asm/unaligned.h>
40 #include <asm/cacheflush.h>
43 /****************************************************************************/
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.
51 #define FLAT_DATA_ALIGN (0x20)
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.
58 #define FLAT_STACK_ALIGN max_t(unsigned long, sizeof(void *), ARCH_SLAB_MINALIGN)
60 #define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */
61 #define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */
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 */
71 bool loaded
; /* Has this library been loaded? */
72 } lib_list
[MAX_SHARED_LIBS
];
75 #ifdef CONFIG_BINFMT_SHARED_FLAT
76 static int load_flat_shared_library(int id
, struct lib_info
*p
);
79 static int load_flat_binary(struct linux_binprm
*);
80 static int flat_core_dump(struct coredump_params
*cprm
);
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
89 /****************************************************************************/
91 * Routine writes a core dump image in the current directory.
92 * Currently only a stub-function.
95 static int flat_core_dump(struct coredump_params
*cprm
)
97 pr_warn("Process %s:%d received signr %d and should have core dumped\n",
98 current
->comm
, current
->pid
, cprm
->siginfo
->si_signo
);
102 /****************************************************************************/
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
106 * addresses on the "stack", recording the new stack pointer value.
109 static int create_flat_tables(struct linux_binprm
*bprm
, unsigned long arg_start
)
112 unsigned long __user
*sp
;
115 p
= (char __user
*)arg_start
;
116 sp
= (unsigned long __user
*)current
->mm
->start_stack
;
118 sp
-= bprm
->envc
+ 1;
119 sp
-= bprm
->argc
+ 1;
120 sp
-= flat_argvp_envp_on_stack() ? 2 : 0;
123 current
->mm
->start_stack
= (unsigned long)sp
& -FLAT_STACK_ALIGN
;
124 sp
= (unsigned long __user
*)current
->mm
->start_stack
;
126 __put_user(bprm
->argc
, sp
++);
127 if (flat_argvp_envp_on_stack()) {
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
++);
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
)
144 current
->mm
->arg_end
= (unsigned long)p
;
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
)
155 current
->mm
->env_end
= (unsigned long)p
;
160 /****************************************************************************/
162 #ifdef CONFIG_BINFMT_ZFLAT
164 #include <linux/zlib.h>
166 #define LBUFSIZE 4000
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 */
177 static int decompress_exec(
178 struct linux_binprm
*bprm
,
179 unsigned long offset
,
189 pr_debug("decompress_exec(offset=%lx,buf=%p,len=%lx)\n", offset
, dst
, len
);
191 memset(&strm
, 0, sizeof(strm
));
192 strm
.workspace
= kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL
);
193 if (strm
.workspace
== NULL
) {
194 pr_debug("no memory for decompress workspace\n");
197 buf
= kmalloc(LBUFSIZE
, GFP_KERNEL
);
199 pr_debug("no memory for read buffer\n");
204 /* Read in first chunk of data and parse gzip header. */
206 ret
= kernel_read(bprm
->file
, offset
, buf
, LBUFSIZE
);
215 /* Check minimum size -- gzip header */
217 pr_debug("file too small?\n");
221 /* Check gzip magic number */
222 if ((buf
[0] != 037) || ((buf
[1] != 0213) && (buf
[1] != 0236))) {
223 pr_debug("unknown compression magic?\n");
227 /* Check gzip method */
229 pr_debug("unknown compression method?\n");
232 /* Check gzip flags */
233 if ((buf
[3] & ENCRYPTED
) || (buf
[3] & CONTINUATION
) ||
234 (buf
[3] & RESERVED
)) {
235 pr_debug("unknown flags?\n");
240 if (buf
[3] & EXTRA_FIELD
) {
241 ret
+= 2 + buf
[10] + (buf
[11] << 8);
242 if (unlikely(ret
>= LBUFSIZE
)) {
243 pr_debug("buffer overflow (EXTRA)?\n");
247 if (buf
[3] & ORIG_NAME
) {
248 while (ret
< LBUFSIZE
&& buf
[ret
++] != 0)
250 if (unlikely(ret
== LBUFSIZE
)) {
251 pr_debug("buffer overflow (ORIG_NAME)?\n");
255 if (buf
[3] & COMMENT
) {
256 while (ret
< LBUFSIZE
&& buf
[ret
++] != 0)
258 if (unlikely(ret
== LBUFSIZE
)) {
259 pr_debug("buffer overflow (COMMENT)?\n");
265 strm
.avail_in
-= ret
;
268 strm
.avail_out
= len
;
271 if (zlib_inflateInit2(&strm
, -MAX_WBITS
) != Z_OK
) {
272 pr_debug("zlib init failed?\n");
276 while ((ret
= zlib_inflate(&strm
, Z_NO_FLUSH
)) == Z_OK
) {
277 ret
= kernel_read(bprm
->file
, fpos
, buf
, LBUFSIZE
);
289 pr_debug("decompression failed (%d), %s\n",
296 zlib_inflateEnd(&strm
);
300 kfree(strm
.workspace
);
304 #endif /* CONFIG_BINFMT_ZFLAT */
306 /****************************************************************************/
309 calc_reloc(unsigned long r
, struct lib_info
*p
, int curid
, int internalp
)
313 unsigned long start_brk
;
314 unsigned long start_data
;
315 unsigned long text_len
;
316 unsigned long start_code
;
318 #ifdef CONFIG_BINFMT_SHARED_FLAT
320 id
= curid
; /* Relocs of 0 are always self referring */
322 id
= (r
>> 24) & 0xff; /* Find ID for this reloc */
323 r
&= 0x00ffffff; /* Trim ID off here */
325 if (id
>= MAX_SHARED_LIBS
) {
326 pr_err("reference 0x%lx to shared library %d", r
, id
);
331 pr_err("reloc address 0x%lx not in same module "
332 "(%d != %d)", r
, curid
, id
);
334 } else if (!p
->lib_list
[id
].loaded
&&
335 load_flat_shared_library(id
, p
) < 0) {
336 pr_err("failed to load library %d", id
);
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
) {
342 pr_err("library %d is younger than %d", id
, curid
);
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
;
355 if (!flat_reloc_valid(r
, start_brk
- start_data
+ text_len
)) {
356 pr_err("reloc outside program 0x%lx (0 - 0x%lx/0x%lx)",
357 r
, start_brk
-start_data
+text_len
, text_len
);
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
;
366 /* Range checked already above so doing the range tests is redundant...*/
370 pr_cont(", killing %s!\n", current
->comm
);
371 send_sig(SIGSEGV
, current
, 0);
376 /****************************************************************************/
378 static void old_reloc(unsigned long rl
)
380 static const char *segment
[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
385 #if defined(CONFIG_COLDFIRE)
386 ptr
= (unsigned long *) (current
->mm
->start_code
+ r
.reloc
.offset
);
388 ptr
= (unsigned long *) (current
->mm
->start_data
+ r
.reloc
.offset
);
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
]);
395 switch (r
.reloc
.type
) {
396 case OLD_FLAT_RELOC_TYPE_TEXT
:
397 *ptr
+= current
->mm
->start_code
;
399 case OLD_FLAT_RELOC_TYPE_DATA
:
400 *ptr
+= current
->mm
->start_data
;
402 case OLD_FLAT_RELOC_TYPE_BSS
:
403 *ptr
+= current
->mm
->end_data
;
406 pr_err("Unknown relocation type=%x\n", r
.reloc
.type
);
410 pr_debug("Relocation became %lx\n", *ptr
);
413 /****************************************************************************/
415 static int load_flat_file(struct linux_binprm
*bprm
,
416 struct lib_info
*libinfo
, int id
, unsigned long *extra_stack
)
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
;
426 unsigned long start_code
, end_code
;
430 hdr
= ((struct flat_hdr
*) bprm
->buf
); /* exec-header */
431 inode
= file_inode(bprm
->file
);
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
);
438 stack_len
+= *extra_stack
;
439 *extra_stack
= stack_len
;
441 relocs
= ntohl(hdr
->reloc_count
);
442 flags
= ntohl(hdr
->flags
);
443 rev
= ntohl(hdr
->rev
);
444 full_data
= data_len
+ relocs
* sizeof(unsigned long);
446 if (strncmp(hdr
->magic
, "bFLT", 4)) {
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.
452 * because a lot of people do not manage to produce good
458 if (flags
& FLAT_FLAG_KTRACE
)
459 pr_info("Loading file: %s\n", bprm
->filename
);
461 if (rev
!= FLAT_VERSION
&& rev
!= OLD_FLAT_VERSION
) {
462 pr_err("bad flat file version 0x%x (supported 0x%lx and 0x%lx)\n",
463 rev
, FLAT_VERSION
, OLD_FLAT_VERSION
);
468 /* Don't allow old format executables to use shared libraries */
469 if (rev
== OLD_FLAT_VERSION
&& id
!= 0) {
470 pr_err("shared libraries are not available before rev 0x%lx\n",
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.
481 if ((text_len
| data_len
| bss_len
| stack_len
| full_data
) >> 28) {
482 pr_err("bad header\n");
488 * fix up the flags for the older format, there were all kinds
489 * of endian hacks, this only works for the simple cases
491 if (rev
== OLD_FLAT_VERSION
&& flat_old_ram_flag(flags
))
492 flags
= FLAT_FLAG_RAM
;
494 #ifndef CONFIG_BINFMT_ZFLAT
495 if (flags
& (FLAT_FLAG_GZIP
|FLAT_FLAG_GZDATA
)) {
496 pr_err("Support for ZFLAT executables is not enabled.\n");
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.
507 rlim
= rlimit(RLIMIT_DATA
);
508 if (rlim
>= RLIM_INFINITY
)
510 if (data_len
+ bss_len
> rlim
) {
515 /* Flush all traces of the currently running executable */
517 ret
= flush_old_exec(bprm
);
521 /* OK, This is the point of no return */
522 set_personality(PER_LINUX_32BIT
);
523 setup_new_exec(bprm
);
527 * calculate the extra space we need to map in
529 extra
= max_t(unsigned long, bss_len
+ stack_len
,
530 relocs
* sizeof(unsigned long));
533 * there are a couple of cases here, the separate code/data
534 * case, and then the fully copied to RAM case which lumps
537 if ((flags
& (FLAT_FLAG_RAM
|FLAT_FLAG_GZIP
)) == 0) {
539 * this should give us a ROM ptr, but if it doesn't we don't
542 pr_debug("ROM mapping of file (we hope)\n");
544 textpos
= vm_mmap(bprm
->file
, 0, text_len
, PROT_READ
|PROT_EXEC
,
545 MAP_PRIVATE
|MAP_EXECUTABLE
, 0);
546 if (!textpos
|| IS_ERR_VALUE(textpos
)) {
550 pr_err("Unable to mmap process text, errno %d\n", ret
);
554 len
= data_len
+ extra
+ MAX_SHARED_LIBS
* sizeof(unsigned long);
555 len
= PAGE_ALIGN(len
);
556 realdatastart
= vm_mmap(NULL
, 0, len
,
557 PROT_READ
|PROT_WRITE
|PROT_EXEC
, MAP_PRIVATE
, 0);
559 if (realdatastart
== 0 || IS_ERR_VALUE(realdatastart
)) {
563 pr_err("Unable to allocate RAM for process data, "
565 vm_munmap(textpos
, text_len
);
568 datapos
= ALIGN(realdatastart
+
569 MAX_SHARED_LIBS
* sizeof(unsigned long),
572 pr_debug("Allocated data+bss+stack (%ld bytes): %lx\n",
573 data_len
+ bss_len
+ stack_len
, datapos
);
575 fpos
= ntohl(hdr
->data_start
);
576 #ifdef CONFIG_BINFMT_ZFLAT
577 if (flags
& FLAT_FLAG_GZDATA
) {
578 result
= decompress_exec(bprm
, fpos
, (char *)datapos
,
583 result
= read_code(bprm
->file
, datapos
, fpos
,
586 if (IS_ERR_VALUE(result
)) {
588 pr_err("Unable to read data+bss, errno %d\n", ret
);
589 vm_munmap(textpos
, text_len
);
590 vm_munmap(realdatastart
, len
);
594 reloc
= (unsigned long *)
595 (datapos
+ (ntohl(hdr
->reloc_start
) - text_len
));
596 memp
= realdatastart
;
600 len
= text_len
+ data_len
+ extra
+ MAX_SHARED_LIBS
* sizeof(unsigned long);
601 len
= PAGE_ALIGN(len
);
602 textpos
= vm_mmap(NULL
, 0, len
,
603 PROT_READ
| PROT_EXEC
| PROT_WRITE
, MAP_PRIVATE
, 0);
605 if (!textpos
|| IS_ERR_VALUE(textpos
)) {
609 pr_err("Unable to allocate RAM for process text/data, "
614 realdatastart
= textpos
+ ntohl(hdr
->data_start
);
615 datapos
= ALIGN(realdatastart
+
616 MAX_SHARED_LIBS
* sizeof(unsigned long),
619 reloc
= (unsigned long *)
620 (datapos
+ (ntohl(hdr
->reloc_start
) - text_len
));
623 #ifdef CONFIG_BINFMT_ZFLAT
625 * load it all in and treat it like a RAM load from now on
627 if (flags
& FLAT_FLAG_GZIP
) {
628 result
= decompress_exec(bprm
, sizeof(struct flat_hdr
),
629 (((char *)textpos
) + sizeof(struct flat_hdr
)),
630 (text_len
+ full_data
631 - sizeof(struct flat_hdr
)),
633 memmove((void *) datapos
, (void *) realdatastart
,
635 } else if (flags
& FLAT_FLAG_GZDATA
) {
636 result
= read_code(bprm
->file
, textpos
, 0, text_len
);
637 if (!IS_ERR_VALUE(result
))
638 result
= decompress_exec(bprm
, text_len
, (char *) datapos
,
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
),
649 if (IS_ERR_VALUE(result
)) {
651 pr_err("Unable to read code+data+bss, errno %d\n", ret
);
652 vm_munmap(textpos
, text_len
+ data_len
+ extra
+
653 MAX_SHARED_LIBS
* sizeof(unsigned long));
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 */
662 /* The main program needs a little extra setup in the task structure */
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
;
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.
672 * Userspace code relies on the stack pointer starting out at
673 * an address right at the end of a page.
675 current
->mm
->start_brk
= datapos
+ data_len
+ bss_len
;
676 current
->mm
->brk
= (current
->mm
->start_brk
+ 3) & ~3;
677 current
->mm
->context
.end_brk
= memp
+ memp_size
- stack_len
;
680 if (flags
& FLAT_FLAG_KTRACE
) {
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);
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
);
699 * We just load the allocations into some temporary memory to
700 * help simplify all this mumbo jumbo
702 * We've got two different sections of relocation entries.
703 * The first is the GOT which resides at the beginning of the data segment
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
710 if (flags
& FLAT_FLAG_GOTPIC
) {
711 for (rp
= (unsigned long *)datapos
; *rp
!= 0xffffffff; rp
++) {
714 addr
= calc_reloc(*rp
, libinfo
, id
, 0);
715 if (addr
== RELOC_FAILED
) {
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).
735 if (rev
> OLD_FLAT_VERSION
) {
736 unsigned long persistent
= 0;
737 for (i
= 0; i
< relocs
; i
++) {
738 unsigned long addr
, relval
;
741 * Get the address of the pointer to be
742 * relocated (of course, the address has to be
745 relval
= ntohl(reloc
[i
]);
746 if (flat_set_persistent(relval
, &persistent
))
748 addr
= flat_get_relocate_addr(relval
);
749 rp
= (unsigned long *) calc_reloc(addr
, libinfo
, id
, 1);
750 if (rp
== (unsigned long *)RELOC_FAILED
) {
755 /* Get the pointer's value. */
756 addr
= flat_get_addr_from_rp(rp
, relval
, flags
,
760 * Do the relocation. PIC relocs in the data section are
761 * already in target order
763 if ((flags
& FLAT_FLAG_GOTPIC
) == 0)
765 addr
= calc_reloc(addr
, libinfo
, id
, 0);
766 if (addr
== RELOC_FAILED
) {
771 /* Write back the relocated pointer. */
772 flat_put_addr_at_rp(rp
, addr
, relval
);
776 for (i
= 0; i
< relocs
; i
++)
777 old_reloc(ntohl(reloc
[i
]));
780 flush_icache_range(start_code
, end_code
);
782 /* zero the BSS, BRK and stack areas */
783 memset((void *)(datapos
+ data_len
), 0, bss_len
+
784 (memp
+ memp_size
- stack_len
- /* end brk */
785 libinfo
->lib_list
[id
].start_brk
) + /* start brk */
794 /****************************************************************************/
795 #ifdef CONFIG_BINFMT_SHARED_FLAT
798 * Load a shared library into memory. The library gets its own data
799 * segment (including bss) but not argv/argc/environ.
802 static int load_flat_shared_library(int id
, struct lib_info
*libs
)
804 struct linux_binprm bprm
;
808 memset(&bprm
, 0, sizeof(bprm
));
810 /* Create the file name */
811 sprintf(buf
, "/lib/lib%d.so", id
);
813 /* Open the file up */
815 bprm
.file
= open_exec(bprm
.filename
);
816 res
= PTR_ERR(bprm
.file
);
817 if (IS_ERR(bprm
.file
))
820 bprm
.cred
= prepare_exec_creds();
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
829 bprm
.cred_prepared
= 1;
831 res
= prepare_binprm(&bprm
);
834 res
= load_flat_file(&bprm
, libs
, id
, NULL
);
836 abort_creds(bprm
.cred
);
839 allow_write_access(bprm
.file
);
845 #endif /* CONFIG_BINFMT_SHARED_FLAT */
846 /****************************************************************************/
849 * These are the functions used to load flat style executables and shared
850 * libraries. There is no binary dependent code anywhere else.
853 static int load_flat_binary(struct linux_binprm
*bprm
)
855 struct lib_info libinfo
;
856 struct pt_regs
*regs
= current_pt_regs();
857 unsigned long stack_len
;
858 unsigned long start_addr
;
862 memset(&libinfo
, 0, sizeof(libinfo
));
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
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
);
876 res
= load_flat_file(bprm
, &libinfo
, 0, &stack_len
);
880 /* Update data segment pointers for all libraries */
881 for (i
= 0; i
< MAX_SHARED_LIBS
; i
++)
882 if (libinfo
.lib_list
[i
].loaded
)
883 for (j
= 0; j
< MAX_SHARED_LIBS
; j
++)
884 (-(j
+1))[(unsigned long *)(libinfo
.lib_list
[i
].start_data
)] =
885 (libinfo
.lib_list
[j
].loaded
) ?
886 libinfo
.lib_list
[j
].start_data
: UNLOADED_LIB
;
888 install_exec_creds(bprm
);
890 set_binfmt(&flat_format
);
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
);
897 /* copy the arg pages onto the stack */
898 res
= transfer_args_to_stack(bprm
, ¤t
->mm
->start_stack
);
900 res
= create_flat_tables(bprm
, current
->mm
->start_stack
);
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).
908 start_addr
= libinfo
.lib_list
[0].entry
;
910 #ifdef CONFIG_BINFMT_SHARED_FLAT
911 for (i
= MAX_SHARED_LIBS
-1; i
> 0; i
--) {
912 if (libinfo
.lib_list
[i
].loaded
) {
913 /* Push previos first to call address */
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
);
918 start_addr
= libinfo
.lib_list
[i
].entry
;
923 #ifdef FLAT_PLAT_INIT
924 FLAT_PLAT_INIT(regs
);
927 pr_debug("start_thread(regs=0x%p, entry=0x%lx, start_stack=0x%lx)\n",
928 regs
, start_addr
, current
->mm
->start_stack
);
929 start_thread(regs
, start_addr
, current
->mm
->start_stack
);
934 /****************************************************************************/
936 static int __init
init_flat_binfmt(void)
938 register_binfmt(&flat_format
);
941 core_initcall(init_flat_binfmt
);
943 /****************************************************************************/
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