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 #include <linux/module.h>
19 #include <linux/kernel.h>
20 #include <linux/sched.h>
22 #include <linux/mman.h>
23 #include <linux/errno.h>
24 #include <linux/signal.h>
25 #include <linux/string.h>
27 #include <linux/file.h>
28 #include <linux/stat.h>
29 #include <linux/fcntl.h>
30 #include <linux/ptrace.h>
31 #include <linux/user.h>
32 #include <linux/slab.h>
33 #include <linux/binfmts.h>
34 #include <linux/personality.h>
35 #include <linux/init.h>
36 #include <linux/flat.h>
37 #include <linux/syscalls.h>
39 #include <asm/byteorder.h>
40 #include <asm/system.h>
41 #include <asm/uaccess.h>
42 #include <asm/unaligned.h>
43 #include <asm/cacheflush.h>
46 /****************************************************************************/
53 #define DBG_FLT(a...) printk(a)
59 * User data (stack, data section and bss) needs to be aligned
60 * for the same reasons as SLAB memory is, and to the same amount.
61 * Avoid duplicating architecture specific code by using the same
62 * macro as with SLAB allocation:
64 #ifdef ARCH_SLAB_MINALIGN
65 #define FLAT_DATA_ALIGN (ARCH_SLAB_MINALIGN)
67 #define FLAT_DATA_ALIGN (sizeof(void *))
70 #define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */
71 #define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */
75 unsigned long start_code
; /* Start of text segment */
76 unsigned long start_data
; /* Start of data segment */
77 unsigned long start_brk
; /* End of data segment */
78 unsigned long text_len
; /* Length of text segment */
79 unsigned long entry
; /* Start address for this module */
80 unsigned long build_date
; /* When this one was compiled */
81 short loaded
; /* Has this library been loaded? */
82 } lib_list
[MAX_SHARED_LIBS
];
85 #ifdef CONFIG_BINFMT_SHARED_FLAT
86 static int load_flat_shared_library(int id
, struct lib_info
*p
);
89 static int load_flat_binary(struct linux_binprm
*, struct pt_regs
* regs
);
90 static int flat_core_dump(long signr
, struct pt_regs
*regs
, struct file
*file
, unsigned long limit
);
92 static struct linux_binfmt flat_format
= {
93 .module
= THIS_MODULE
,
94 .load_binary
= load_flat_binary
,
95 .core_dump
= flat_core_dump
,
96 .min_coredump
= PAGE_SIZE
99 /****************************************************************************/
101 * Routine writes a core dump image in the current directory.
102 * Currently only a stub-function.
105 static int flat_core_dump(long signr
, struct pt_regs
*regs
, struct file
*file
, unsigned long limit
)
107 printk("Process %s:%d received signr %d and should have core dumped\n",
108 current
->comm
, current
->pid
, (int) signr
);
112 /****************************************************************************/
114 * create_flat_tables() parses the env- and arg-strings in new user
115 * memory and creates the pointer tables from them, and puts their
116 * addresses on the "stack", returning the new stack pointer value.
119 static unsigned long create_flat_tables(
121 struct linux_binprm
* bprm
)
123 unsigned long *argv
,*envp
;
125 char * p
= (char*)pp
;
126 int argc
= bprm
->argc
;
127 int envc
= bprm
->envc
;
128 char uninitialized_var(dummy
);
130 sp
= (unsigned long *)p
;
131 sp
-= (envc
+ argc
+ 2) + 1 + (flat_argvp_envp_on_stack() ? 2 : 0);
132 sp
= (unsigned long *) ((unsigned long)sp
& -FLAT_DATA_ALIGN
);
133 argv
= sp
+ 1 + (flat_argvp_envp_on_stack() ? 2 : 0);
134 envp
= argv
+ (argc
+ 1);
136 if (flat_argvp_envp_on_stack()) {
137 put_user((unsigned long) envp
, sp
+ 2);
138 put_user((unsigned long) argv
, sp
+ 1);
142 current
->mm
->arg_start
= (unsigned long) p
;
144 put_user((unsigned long) p
, argv
++);
146 get_user(dummy
, p
); p
++;
149 put_user((unsigned long) NULL
, argv
);
150 current
->mm
->arg_end
= current
->mm
->env_start
= (unsigned long) p
;
152 put_user((unsigned long)p
, envp
); envp
++;
154 get_user(dummy
, p
); p
++;
157 put_user((unsigned long) NULL
, envp
);
158 current
->mm
->env_end
= (unsigned long) p
;
159 return (unsigned long)sp
;
162 /****************************************************************************/
164 #ifdef CONFIG_BINFMT_ZFLAT
166 #include <linux/zlib.h>
168 #define LBUFSIZE 4000
171 #define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */
172 #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
173 #define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
174 #define ORIG_NAME 0x08 /* bit 3 set: original file name present */
175 #define COMMENT 0x10 /* bit 4 set: file comment present */
176 #define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */
177 #define RESERVED 0xC0 /* bit 6,7: reserved */
179 static int decompress_exec(
180 struct linux_binprm
*bprm
,
181 unsigned long offset
,
191 DBG_FLT("decompress_exec(offset=%x,buf=%x,len=%x)\n",(int)offset
, (int)dst
, (int)len
);
193 memset(&strm
, 0, sizeof(strm
));
194 strm
.workspace
= kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL
);
195 if (strm
.workspace
== NULL
) {
196 DBG_FLT("binfmt_flat: no memory for decompress workspace\n");
199 buf
= kmalloc(LBUFSIZE
, GFP_KERNEL
);
201 DBG_FLT("binfmt_flat: no memory for read buffer\n");
206 /* Read in first chunk of data and parse gzip header. */
208 ret
= bprm
->file
->f_op
->read(bprm
->file
, buf
, LBUFSIZE
, &fpos
);
216 /* Check minimum size -- gzip header */
218 DBG_FLT("binfmt_flat: file too small?\n");
222 /* Check gzip magic number */
223 if ((buf
[0] != 037) || ((buf
[1] != 0213) && (buf
[1] != 0236))) {
224 DBG_FLT("binfmt_flat: unknown compression magic?\n");
228 /* Check gzip method */
230 DBG_FLT("binfmt_flat: unknown compression method?\n");
233 /* Check gzip flags */
234 if ((buf
[3] & ENCRYPTED
) || (buf
[3] & CONTINUATION
) ||
235 (buf
[3] & RESERVED
)) {
236 DBG_FLT("binfmt_flat: unknown flags?\n");
241 if (buf
[3] & EXTRA_FIELD
) {
242 ret
+= 2 + buf
[10] + (buf
[11] << 8);
243 if (unlikely(LBUFSIZE
<= ret
)) {
244 DBG_FLT("binfmt_flat: buffer overflow (EXTRA)?\n");
248 if (buf
[3] & ORIG_NAME
) {
249 while (ret
< LBUFSIZE
&& buf
[ret
++] != 0)
251 if (unlikely(LBUFSIZE
== ret
)) {
252 DBG_FLT("binfmt_flat: buffer overflow (ORIG_NAME)?\n");
256 if (buf
[3] & COMMENT
) {
257 while (ret
< LBUFSIZE
&& buf
[ret
++] != 0)
259 if (unlikely(LBUFSIZE
== ret
)) {
260 DBG_FLT("binfmt_flat: buffer overflow (COMMENT)?\n");
266 strm
.avail_in
-= ret
;
269 strm
.avail_out
= len
;
272 if (zlib_inflateInit2(&strm
, -MAX_WBITS
) != Z_OK
) {
273 DBG_FLT("binfmt_flat: zlib init failed?\n");
277 while ((ret
= zlib_inflate(&strm
, Z_NO_FLUSH
)) == Z_OK
) {
278 ret
= bprm
->file
->f_op
->read(bprm
->file
, buf
, LBUFSIZE
, &fpos
);
281 if (ret
>= (unsigned long) -4096)
291 DBG_FLT("binfmt_flat: decompression failed (%d), %s\n",
298 zlib_inflateEnd(&strm
);
302 kfree(strm
.workspace
);
306 #endif /* CONFIG_BINFMT_ZFLAT */
308 /****************************************************************************/
311 calc_reloc(unsigned long r
, struct lib_info
*p
, int curid
, int internalp
)
315 unsigned long start_brk
;
316 unsigned long start_data
;
317 unsigned long text_len
;
318 unsigned long start_code
;
320 #ifdef CONFIG_BINFMT_SHARED_FLAT
322 id
= curid
; /* Relocs of 0 are always self referring */
324 id
= (r
>> 24) & 0xff; /* Find ID for this reloc */
325 r
&= 0x00ffffff; /* Trim ID off here */
327 if (id
>= MAX_SHARED_LIBS
) {
328 printk("BINFMT_FLAT: reference 0x%x to shared library %d",
334 printk("BINFMT_FLAT: reloc address 0x%x not in same module "
335 "(%d != %d)", (unsigned) r
, curid
, id
);
337 } else if ( ! p
->lib_list
[id
].loaded
&&
338 load_flat_shared_library(id
, p
) > (unsigned long) -4096) {
339 printk("BINFMT_FLAT: failed to load library %d", id
);
342 /* Check versioning information (i.e. time stamps) */
343 if (p
->lib_list
[id
].build_date
&& p
->lib_list
[curid
].build_date
&&
344 p
->lib_list
[curid
].build_date
< p
->lib_list
[id
].build_date
) {
345 printk("BINFMT_FLAT: library %d is younger than %d", id
, curid
);
353 start_brk
= p
->lib_list
[id
].start_brk
;
354 start_data
= p
->lib_list
[id
].start_data
;
355 start_code
= p
->lib_list
[id
].start_code
;
356 text_len
= p
->lib_list
[id
].text_len
;
358 if (!flat_reloc_valid(r
, start_brk
- start_data
+ text_len
)) {
359 printk("BINFMT_FLAT: reloc outside program 0x%x (0 - 0x%x/0x%x)",
360 (int) r
,(int)(start_brk
-start_code
),(int)text_len
);
364 if (r
< text_len
) /* In text segment */
365 addr
= r
+ start_code
;
366 else /* In data segment */
367 addr
= r
- text_len
+ start_data
;
369 /* Range checked already above so doing the range tests is redundant...*/
373 printk(", killing %s!\n", current
->comm
);
374 send_sig(SIGSEGV
, current
, 0);
379 /****************************************************************************/
381 void old_reloc(unsigned long rl
)
384 char *segment
[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
390 #if defined(CONFIG_COLDFIRE)
391 ptr
= (unsigned long *) (current
->mm
->start_code
+ r
.reloc
.offset
);
393 ptr
= (unsigned long *) (current
->mm
->start_data
+ r
.reloc
.offset
);
397 printk("Relocation of variable at DATASEG+%x "
398 "(address %p, currently %x) into segment %s\n",
399 r
.reloc
.offset
, ptr
, (int)*ptr
, segment
[r
.reloc
.type
]);
402 switch (r
.reloc
.type
) {
403 case OLD_FLAT_RELOC_TYPE_TEXT
:
404 *ptr
+= current
->mm
->start_code
;
406 case OLD_FLAT_RELOC_TYPE_DATA
:
407 *ptr
+= current
->mm
->start_data
;
409 case OLD_FLAT_RELOC_TYPE_BSS
:
410 *ptr
+= current
->mm
->end_data
;
413 printk("BINFMT_FLAT: Unknown relocation type=%x\n", r
.reloc
.type
);
418 printk("Relocation became %x\n", (int)*ptr
);
422 /****************************************************************************/
424 static int load_flat_file(struct linux_binprm
* bprm
,
425 struct lib_info
*libinfo
, int id
, unsigned long *extra_stack
)
427 struct flat_hdr
* hdr
;
428 unsigned long textpos
= 0, datapos
= 0, result
;
429 unsigned long realdatastart
= 0;
430 unsigned long text_len
, data_len
, bss_len
, stack_len
, flags
;
431 unsigned long len
, memp
= 0;
432 unsigned long memp_size
, extra
, rlim
;
433 unsigned long *reloc
= 0, *rp
;
435 int i
, rev
, relocs
= 0;
437 unsigned long start_code
, end_code
;
440 hdr
= ((struct flat_hdr
*) bprm
->buf
); /* exec-header */
441 inode
= bprm
->file
->f_path
.dentry
->d_inode
;
443 text_len
= ntohl(hdr
->data_start
);
444 data_len
= ntohl(hdr
->data_end
) - ntohl(hdr
->data_start
);
445 bss_len
= ntohl(hdr
->bss_end
) - ntohl(hdr
->data_end
);
446 stack_len
= ntohl(hdr
->stack_size
);
448 stack_len
+= *extra_stack
;
449 *extra_stack
= stack_len
;
451 relocs
= ntohl(hdr
->reloc_count
);
452 flags
= ntohl(hdr
->flags
);
453 rev
= ntohl(hdr
->rev
);
455 if (strncmp(hdr
->magic
, "bFLT", 4)) {
457 * Previously, here was a printk to tell people
458 * "BINFMT_FLAT: bad header magic".
459 * But for the kernel which also use ELF FD-PIC format, this
460 * error message is confusing.
461 * because a lot of people do not manage to produce good
467 if (flags
& FLAT_FLAG_KTRACE
)
468 printk("BINFMT_FLAT: Loading file: %s\n", bprm
->filename
);
470 if (rev
!= FLAT_VERSION
&& rev
!= OLD_FLAT_VERSION
) {
471 printk("BINFMT_FLAT: bad flat file version 0x%x (supported "
472 "0x%lx and 0x%lx)\n",
473 rev
, FLAT_VERSION
, OLD_FLAT_VERSION
);
478 /* Don't allow old format executables to use shared libraries */
479 if (rev
== OLD_FLAT_VERSION
&& id
!= 0) {
480 printk("BINFMT_FLAT: shared libraries are not available before rev 0x%x\n",
487 * fix up the flags for the older format, there were all kinds
488 * of endian hacks, this only works for the simple cases
490 if (rev
== OLD_FLAT_VERSION
&& flat_old_ram_flag(flags
))
491 flags
= FLAT_FLAG_RAM
;
493 #ifndef CONFIG_BINFMT_ZFLAT
494 if (flags
& (FLAT_FLAG_GZIP
|FLAT_FLAG_GZDATA
)) {
495 printk("Support for ZFLAT executables is not enabled.\n");
502 * Check initial limits. This avoids letting people circumvent
503 * size limits imposed on them by creating programs with large
504 * arrays in the data or bss.
506 rlim
= current
->signal
->rlim
[RLIMIT_DATA
].rlim_cur
;
507 if (rlim
>= RLIM_INFINITY
)
509 if (data_len
+ bss_len
> rlim
) {
514 /* Flush all traces of the currently running executable */
516 result
= flush_old_exec(bprm
);
522 /* OK, This is the point of no return */
523 set_personality(PER_LINUX_32BIT
);
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 DBG_FLT("BINFMT_FLAT: ROM mapping of file (we hope)\n");
544 down_write(¤t
->mm
->mmap_sem
);
545 textpos
= do_mmap(bprm
->file
, 0, text_len
, PROT_READ
|PROT_EXEC
,
546 MAP_PRIVATE
|MAP_EXECUTABLE
, 0);
547 up_write(¤t
->mm
->mmap_sem
);
548 if (!textpos
|| textpos
>= (unsigned long) -4096) {
550 textpos
= (unsigned long) -ENOMEM
;
551 printk("Unable to mmap process text, errno %d\n", (int)-textpos
);
556 len
= data_len
+ extra
+ MAX_SHARED_LIBS
* sizeof(unsigned long);
557 len
= PAGE_ALIGN(len
);
558 down_write(¤t
->mm
->mmap_sem
);
559 realdatastart
= do_mmap(0, 0, len
,
560 PROT_READ
|PROT_WRITE
|PROT_EXEC
, MAP_PRIVATE
, 0);
561 up_write(¤t
->mm
->mmap_sem
);
563 if (realdatastart
== 0 || realdatastart
>= (unsigned long)-4096) {
565 realdatastart
= (unsigned long) -ENOMEM
;
566 printk("Unable to allocate RAM for process data, errno %d\n",
567 (int)-realdatastart
);
568 do_munmap(current
->mm
, textpos
, text_len
);
572 datapos
= ALIGN(realdatastart
+
573 MAX_SHARED_LIBS
* sizeof(unsigned long),
576 DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n",
577 (int)(data_len
+ bss_len
+ stack_len
), (int)datapos
);
579 fpos
= ntohl(hdr
->data_start
);
580 #ifdef CONFIG_BINFMT_ZFLAT
581 if (flags
& FLAT_FLAG_GZDATA
) {
582 result
= decompress_exec(bprm
, fpos
, (char *) datapos
,
583 data_len
+ (relocs
* sizeof(unsigned long)), 0);
587 result
= bprm
->file
->f_op
->read(bprm
->file
, (char *) datapos
,
588 data_len
+ (relocs
* sizeof(unsigned long)), &fpos
);
590 if (result
>= (unsigned long)-4096) {
591 printk("Unable to read data+bss, errno %d\n", (int)-result
);
592 do_munmap(current
->mm
, textpos
, text_len
);
593 do_munmap(current
->mm
, realdatastart
, data_len
+ extra
);
598 reloc
= (unsigned long *) (datapos
+(ntohl(hdr
->reloc_start
)-text_len
));
599 memp
= realdatastart
;
603 len
= text_len
+ data_len
+ extra
+ MAX_SHARED_LIBS
* sizeof(unsigned long);
604 len
= PAGE_ALIGN(len
);
605 down_write(¤t
->mm
->mmap_sem
);
606 textpos
= do_mmap(0, 0, len
,
607 PROT_READ
| PROT_EXEC
| PROT_WRITE
, MAP_PRIVATE
, 0);
608 up_write(¤t
->mm
->mmap_sem
);
610 if (!textpos
|| textpos
>= (unsigned long) -4096) {
612 textpos
= (unsigned long) -ENOMEM
;
613 printk("Unable to allocate RAM for process text/data, errno %d\n",
619 realdatastart
= textpos
+ ntohl(hdr
->data_start
);
620 datapos
= ALIGN(realdatastart
+
621 MAX_SHARED_LIBS
* sizeof(unsigned long),
624 reloc
= (unsigned long *)
625 (datapos
+ (ntohl(hdr
->reloc_start
) - text_len
));
628 #ifdef CONFIG_BINFMT_ZFLAT
630 * load it all in and treat it like a RAM load from now on
632 if (flags
& FLAT_FLAG_GZIP
) {
633 result
= decompress_exec(bprm
, sizeof (struct flat_hdr
),
634 (((char *) textpos
) + sizeof (struct flat_hdr
)),
635 (text_len
+ data_len
+ (relocs
* sizeof(unsigned long))
636 - sizeof (struct flat_hdr
)),
638 memmove((void *) datapos
, (void *) realdatastart
,
639 data_len
+ (relocs
* sizeof(unsigned long)));
640 } else if (flags
& FLAT_FLAG_GZDATA
) {
642 result
= bprm
->file
->f_op
->read(bprm
->file
,
643 (char *) textpos
, text_len
, &fpos
);
644 if (result
< (unsigned long) -4096)
645 result
= decompress_exec(bprm
, text_len
, (char *) datapos
,
646 data_len
+ (relocs
* sizeof(unsigned long)), 0);
652 result
= bprm
->file
->f_op
->read(bprm
->file
,
653 (char *) textpos
, text_len
, &fpos
);
654 if (result
< (unsigned long) -4096) {
655 fpos
= ntohl(hdr
->data_start
);
656 result
= bprm
->file
->f_op
->read(bprm
->file
, (char *) datapos
,
657 data_len
+ (relocs
* sizeof(unsigned long)), &fpos
);
660 if (result
>= (unsigned long)-4096) {
661 printk("Unable to read code+data+bss, errno %d\n",(int)-result
);
662 do_munmap(current
->mm
, textpos
, text_len
+ data_len
+ extra
+
663 MAX_SHARED_LIBS
* sizeof(unsigned long));
669 if (flags
& FLAT_FLAG_KTRACE
)
670 printk("Mapping is %x, Entry point is %x, data_start is %x\n",
671 (int)textpos
, 0x00ffffff&ntohl(hdr
->entry
), ntohl(hdr
->data_start
));
673 /* The main program needs a little extra setup in the task structure */
674 start_code
= textpos
+ sizeof (struct flat_hdr
);
675 end_code
= textpos
+ text_len
;
677 current
->mm
->start_code
= start_code
;
678 current
->mm
->end_code
= end_code
;
679 current
->mm
->start_data
= datapos
;
680 current
->mm
->end_data
= datapos
+ data_len
;
682 * set up the brk stuff, uses any slack left in data/bss/stack
683 * allocation. We put the brk after the bss (between the bss
684 * and stack) like other platforms.
685 * Userspace code relies on the stack pointer starting out at
686 * an address right at the end of a page.
688 current
->mm
->start_brk
= datapos
+ data_len
+ bss_len
;
689 current
->mm
->brk
= (current
->mm
->start_brk
+ 3) & ~3;
690 current
->mm
->context
.end_brk
= memp
+ memp_size
- stack_len
;
693 if (flags
& FLAT_FLAG_KTRACE
)
694 printk("%s %s: TEXT=%x-%x DATA=%x-%x BSS=%x-%x\n",
695 id
? "Lib" : "Load", bprm
->filename
,
696 (int) start_code
, (int) end_code
,
698 (int) (datapos
+ data_len
),
699 (int) (datapos
+ data_len
),
700 (int) (((datapos
+ data_len
+ bss_len
) + 3) & ~3));
702 text_len
-= sizeof(struct flat_hdr
); /* the real code len */
704 /* Store the current module values into the global library structure */
705 libinfo
->lib_list
[id
].start_code
= start_code
;
706 libinfo
->lib_list
[id
].start_data
= datapos
;
707 libinfo
->lib_list
[id
].start_brk
= datapos
+ data_len
+ bss_len
;
708 libinfo
->lib_list
[id
].text_len
= text_len
;
709 libinfo
->lib_list
[id
].loaded
= 1;
710 libinfo
->lib_list
[id
].entry
= (0x00ffffff & ntohl(hdr
->entry
)) + textpos
;
711 libinfo
->lib_list
[id
].build_date
= ntohl(hdr
->build_date
);
714 * We just load the allocations into some temporary memory to
715 * help simplify all this mumbo jumbo
717 * We've got two different sections of relocation entries.
718 * The first is the GOT which resides at the begining of the data segment
719 * and is terminated with a -1. This one can be relocated in place.
720 * The second is the extra relocation entries tacked after the image's
721 * data segment. These require a little more processing as the entry is
722 * really an offset into the image which contains an offset into the
725 if (flags
& FLAT_FLAG_GOTPIC
) {
726 for (rp
= (unsigned long *)datapos
; *rp
!= 0xffffffff; rp
++) {
729 addr
= calc_reloc(*rp
, libinfo
, id
, 0);
730 if (addr
== RELOC_FAILED
) {
740 * Now run through the relocation entries.
741 * We've got to be careful here as C++ produces relocatable zero
742 * entries in the constructor and destructor tables which are then
743 * tested for being not zero (which will always occur unless we're
744 * based from address zero). This causes an endless loop as __start
745 * is at zero. The solution used is to not relocate zero addresses.
746 * This has the negative side effect of not allowing a global data
747 * reference to be statically initialised to _stext (I've moved
748 * __start to address 4 so that is okay).
750 if (rev
> OLD_FLAT_VERSION
) {
751 unsigned long persistent
= 0;
752 for (i
=0; i
< relocs
; i
++) {
753 unsigned long addr
, relval
;
755 /* Get the address of the pointer to be
756 relocated (of course, the address has to be
758 relval
= ntohl(reloc
[i
]);
759 if (flat_set_persistent (relval
, &persistent
))
761 addr
= flat_get_relocate_addr(relval
);
762 rp
= (unsigned long *) calc_reloc(addr
, libinfo
, id
, 1);
763 if (rp
== (unsigned long *)RELOC_FAILED
) {
768 /* Get the pointer's value. */
769 addr
= flat_get_addr_from_rp(rp
, relval
, flags
,
773 * Do the relocation. PIC relocs in the data section are
774 * already in target order
776 if ((flags
& FLAT_FLAG_GOTPIC
) == 0)
778 addr
= calc_reloc(addr
, libinfo
, id
, 0);
779 if (addr
== RELOC_FAILED
) {
784 /* Write back the relocated pointer. */
785 flat_put_addr_at_rp(rp
, addr
, relval
);
789 for (i
=0; i
< relocs
; i
++)
790 old_reloc(ntohl(reloc
[i
]));
793 flush_icache_range(start_code
, end_code
);
795 /* zero the BSS, BRK and stack areas */
796 memset((void*)(datapos
+ data_len
), 0, bss_len
+
797 (memp
+ memp_size
- stack_len
- /* end brk */
798 libinfo
->lib_list
[id
].start_brk
) + /* start brk */
807 /****************************************************************************/
808 #ifdef CONFIG_BINFMT_SHARED_FLAT
811 * Load a shared library into memory. The library gets its own data
812 * segment (including bss) but not argv/argc/environ.
815 static int load_flat_shared_library(int id
, struct lib_info
*libs
)
817 struct linux_binprm bprm
;
821 /* Create the file name */
822 sprintf(buf
, "/lib/lib%d.so", id
);
824 /* Open the file up */
826 bprm
.file
= open_exec(bprm
.filename
);
827 res
= PTR_ERR(bprm
.file
);
828 if (IS_ERR(bprm
.file
))
831 res
= prepare_binprm(&bprm
);
833 if (res
<= (unsigned long)-4096)
834 res
= load_flat_file(&bprm
, libs
, id
, NULL
);
836 allow_write_access(bprm
.file
);
843 #endif /* CONFIG_BINFMT_SHARED_FLAT */
844 /****************************************************************************/
847 * These are the functions used to load flat style executables and shared
848 * libraries. There is no binary dependent code anywhere else.
851 static int load_flat_binary(struct linux_binprm
* bprm
, struct pt_regs
* regs
)
853 struct lib_info libinfo
;
854 unsigned long p
= bprm
->p
;
855 unsigned long stack_len
;
856 unsigned long start_addr
;
861 memset(&libinfo
, 0, sizeof(libinfo
));
863 * We have to add the size of our arguments to our stack size
864 * otherwise it's too easy for users to create stack overflows
865 * by passing in a huge argument list. And yes, we have to be
866 * pedantic and include space for the argv/envp array as it may have
869 #define TOP_OF_ARGS (PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *))
870 stack_len
= TOP_OF_ARGS
- bprm
->p
; /* the strings */
871 stack_len
+= (bprm
->argc
+ 1) * sizeof(char *); /* the argv array */
872 stack_len
+= (bprm
->envc
+ 1) * sizeof(char *); /* the envp array */
873 stack_len
+= FLAT_DATA_ALIGN
- 1; /* reserve for upcoming alignment */
875 res
= load_flat_file(bprm
, &libinfo
, 0, &stack_len
);
876 if (res
> (unsigned long)-4096)
879 /* Update data segment pointers for all libraries */
880 for (i
=0; i
<MAX_SHARED_LIBS
; i
++)
881 if (libinfo
.lib_list
[i
].loaded
)
882 for (j
=0; j
<MAX_SHARED_LIBS
; j
++)
883 (-(j
+1))[(unsigned long *)(libinfo
.lib_list
[i
].start_data
)] =
884 (libinfo
.lib_list
[j
].loaded
)?
885 libinfo
.lib_list
[j
].start_data
:UNLOADED_LIB
;
887 install_exec_creds(bprm
);
888 current
->flags
&= ~PF_FORKNOEXEC
;
890 set_binfmt(&flat_format
);
892 p
= ((current
->mm
->context
.end_brk
+ stack_len
+ 3) & ~3) - 4;
893 DBG_FLT("p=%x\n", (int)p
);
895 /* copy the arg pages onto the stack, this could be more efficient :-) */
896 for (i
= TOP_OF_ARGS
- 1; i
>= bprm
->p
; i
--)
898 ((char *) page_address(bprm
->page
[i
/PAGE_SIZE
]))[i
% PAGE_SIZE
];
900 sp
= (unsigned long *) create_flat_tables(p
, bprm
);
902 /* Fake some return addresses to ensure the call chain will
903 * initialise library in order for us. We are required to call
904 * lib 1 first, then 2, ... and finally the main program (id 0).
906 start_addr
= libinfo
.lib_list
[0].entry
;
908 #ifdef CONFIG_BINFMT_SHARED_FLAT
909 for (i
= MAX_SHARED_LIBS
-1; i
>0; i
--) {
910 if (libinfo
.lib_list
[i
].loaded
) {
911 /* Push previos first to call address */
912 --sp
; put_user(start_addr
, sp
);
913 start_addr
= libinfo
.lib_list
[i
].entry
;
918 /* Stash our initial stack pointer into the mm structure */
919 current
->mm
->start_stack
= (unsigned long )sp
;
921 #ifdef FLAT_PLAT_INIT
922 FLAT_PLAT_INIT(regs
);
924 DBG_FLT("start_thread(regs=0x%x, entry=0x%x, start_stack=0x%x)\n",
925 (int)regs
, (int)start_addr
, (int)current
->mm
->start_stack
);
927 start_thread(regs
, start_addr
, current
->mm
->start_stack
);
932 /****************************************************************************/
934 static int __init
init_flat_binfmt(void)
936 return register_binfmt(&flat_format
);
939 /****************************************************************************/
941 core_initcall(init_flat_binfmt
);
943 /****************************************************************************/
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