1 /* binfmt_elf_fdpic.c: FDPIC ELF binary format
3 * Copyright (C) 2003, 2004 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 * Derived from binfmt_elf.c
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
13 #include <linux/module.h>
16 #include <linux/stat.h>
17 #include <linux/sched.h>
19 #include <linux/mman.h>
20 #include <linux/errno.h>
21 #include <linux/signal.h>
22 #include <linux/binfmts.h>
23 #include <linux/string.h>
24 #include <linux/file.h>
25 #include <linux/fcntl.h>
26 #include <linux/slab.h>
27 #include <linux/highmem.h>
28 #include <linux/personality.h>
29 #include <linux/ptrace.h>
30 #include <linux/init.h>
31 #include <linux/smp_lock.h>
32 #include <linux/elf.h>
33 #include <linux/elf-fdpic.h>
34 #include <linux/elfcore.h>
36 #include <asm/uaccess.h>
37 #include <asm/param.h>
38 #include <asm/pgalloc.h>
40 typedef char *elf_caddr_t
;
42 #define elf_addr_t unsigned long
46 #define kdebug(fmt, ...) printk("FDPIC "fmt"\n" ,##__VA_ARGS__ )
48 #define kdebug(fmt, ...) do {} while(0)
51 MODULE_LICENSE("GPL");
53 static int load_elf_fdpic_binary(struct linux_binprm
*bprm
, struct pt_regs
*regs
);
54 //static int load_elf_fdpic_library(struct file *);
55 static int elf_fdpic_fetch_phdrs(struct elf_fdpic_params
*params
, struct file
*file
);
56 static int elf_fdpic_map_file(struct elf_fdpic_params
*params
,
61 static int create_elf_fdpic_tables(struct linux_binprm
*bprm
,
63 struct elf_fdpic_params
*exec_params
,
64 struct elf_fdpic_params
*interp_params
);
67 static int elf_fdpic_transfer_args_to_stack(struct linux_binprm
*bprm
, unsigned long *_sp
);
68 static int elf_fdpic_map_file_constdisp_on_uclinux(struct elf_fdpic_params
*params
,
70 struct mm_struct
*mm
);
73 static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params
*params
,
75 struct mm_struct
*mm
);
77 static struct linux_binfmt elf_fdpic_format
= {
78 .module
= THIS_MODULE
,
79 .load_binary
= load_elf_fdpic_binary
,
80 // .load_shlib = load_elf_fdpic_library,
81 // .core_dump = elf_fdpic_core_dump,
82 .min_coredump
= ELF_EXEC_PAGESIZE
,
85 static int __init
init_elf_fdpic_binfmt(void) { return register_binfmt(&elf_fdpic_format
); }
86 static void __exit
exit_elf_fdpic_binfmt(void) { unregister_binfmt(&elf_fdpic_format
); }
88 module_init(init_elf_fdpic_binfmt
)
89 module_exit(exit_elf_fdpic_binfmt
)
91 static int is_elf_fdpic(struct elfhdr
*hdr
, struct file
*file
)
93 if (memcmp(hdr
->e_ident
, ELFMAG
, SELFMAG
) != 0)
95 if (hdr
->e_type
!= ET_EXEC
&& hdr
->e_type
!= ET_DYN
)
97 if (!elf_check_arch(hdr
) || !elf_check_fdpic(hdr
))
99 if (!file
->f_op
|| !file
->f_op
->mmap
)
104 /*****************************************************************************/
106 * read the program headers table into memory
108 static int elf_fdpic_fetch_phdrs(struct elf_fdpic_params
*params
, struct file
*file
)
110 struct elf32_phdr
*phdr
;
114 if (params
->hdr
.e_phentsize
!= sizeof(struct elf_phdr
))
116 if (params
->hdr
.e_phnum
> 65536U / sizeof(struct elf_phdr
))
119 size
= params
->hdr
.e_phnum
* sizeof(struct elf_phdr
);
120 params
->phdrs
= kmalloc(size
, GFP_KERNEL
);
124 retval
= kernel_read(file
, params
->hdr
.e_phoff
, (char *) params
->phdrs
, size
);
128 /* determine stack size for this binary */
129 phdr
= params
->phdrs
;
130 for (loop
= 0; loop
< params
->hdr
.e_phnum
; loop
++, phdr
++) {
131 if (phdr
->p_type
!= PT_GNU_STACK
)
134 if (phdr
->p_flags
& PF_X
)
135 params
->flags
|= ELF_FDPIC_FLAG_EXEC_STACK
;
137 params
->flags
|= ELF_FDPIC_FLAG_NOEXEC_STACK
;
139 params
->stack_size
= phdr
->p_memsz
;
144 } /* end elf_fdpic_fetch_phdrs() */
146 /*****************************************************************************/
148 * load an fdpic binary into various bits of memory
150 static int load_elf_fdpic_binary(struct linux_binprm
*bprm
, struct pt_regs
*regs
)
152 struct elf_fdpic_params exec_params
, interp_params
;
153 struct elf_phdr
*phdr
;
154 unsigned long stack_size
;
155 struct file
*interpreter
= NULL
; /* to shut gcc up */
156 char *interpreter_name
= NULL
;
157 int executable_stack
;
160 memset(&exec_params
, 0, sizeof(exec_params
));
161 memset(&interp_params
, 0, sizeof(interp_params
));
163 exec_params
.hdr
= *(struct elfhdr
*) bprm
->buf
;
164 exec_params
.flags
= ELF_FDPIC_FLAG_PRESENT
| ELF_FDPIC_FLAG_EXECUTABLE
;
166 /* check that this is a binary we know how to deal with */
168 if (!is_elf_fdpic(&exec_params
.hdr
, bprm
->file
))
171 /* read the program header table */
172 retval
= elf_fdpic_fetch_phdrs(&exec_params
, bprm
->file
);
176 /* scan for a program header that specifies an interpreter */
177 phdr
= exec_params
.phdrs
;
179 for (i
= 0; i
< exec_params
.hdr
.e_phnum
; i
++, phdr
++) {
180 switch (phdr
->p_type
) {
183 if (phdr
->p_filesz
> PATH_MAX
)
186 if (phdr
->p_filesz
< 2)
189 /* read the name of the interpreter into memory */
190 interpreter_name
= kmalloc(phdr
->p_filesz
, GFP_KERNEL
);
191 if (!interpreter_name
)
194 retval
= kernel_read(bprm
->file
,
202 if (interpreter_name
[phdr
->p_filesz
- 1] != '\0')
205 kdebug("Using ELF interpreter %s", interpreter_name
);
207 /* replace the program with the interpreter */
208 interpreter
= open_exec(interpreter_name
);
209 retval
= PTR_ERR(interpreter
);
210 if (IS_ERR(interpreter
)) {
215 retval
= kernel_read(interpreter
, 0, bprm
->buf
, BINPRM_BUF_SIZE
);
219 interp_params
.hdr
= *((struct elfhdr
*) bprm
->buf
);
224 if (exec_params
.load_addr
== 0)
225 exec_params
.load_addr
= phdr
->p_vaddr
;
232 if (elf_check_const_displacement(&exec_params
.hdr
))
233 exec_params
.flags
|= ELF_FDPIC_FLAG_CONSTDISP
;
235 /* perform insanity checks on the interpreter */
236 if (interpreter_name
) {
238 if (!is_elf_fdpic(&interp_params
.hdr
, interpreter
))
241 interp_params
.flags
= ELF_FDPIC_FLAG_PRESENT
;
243 /* read the interpreter's program header table */
244 retval
= elf_fdpic_fetch_phdrs(&interp_params
, interpreter
);
249 stack_size
= exec_params
.stack_size
;
250 if (stack_size
< interp_params
.stack_size
)
251 stack_size
= interp_params
.stack_size
;
253 if (exec_params
.flags
& ELF_FDPIC_FLAG_EXEC_STACK
)
254 executable_stack
= EXSTACK_ENABLE_X
;
255 else if (exec_params
.flags
& ELF_FDPIC_FLAG_NOEXEC_STACK
)
256 executable_stack
= EXSTACK_DISABLE_X
;
257 else if (interp_params
.flags
& ELF_FDPIC_FLAG_EXEC_STACK
)
258 executable_stack
= EXSTACK_ENABLE_X
;
259 else if (interp_params
.flags
& ELF_FDPIC_FLAG_NOEXEC_STACK
)
260 executable_stack
= EXSTACK_DISABLE_X
;
262 executable_stack
= EXSTACK_DEFAULT
;
268 if (elf_check_const_displacement(&interp_params
.hdr
))
269 interp_params
.flags
|= ELF_FDPIC_FLAG_CONSTDISP
;
271 /* flush all traces of the currently running executable */
272 retval
= flush_old_exec(bprm
);
276 /* there's now no turning back... the old userspace image is dead,
277 * defunct, deceased, etc. after this point we have to exit via
279 set_personality(PER_LINUX_FDPIC
);
280 set_binfmt(&elf_fdpic_format
);
282 current
->mm
->start_code
= 0;
283 current
->mm
->end_code
= 0;
284 current
->mm
->start_stack
= 0;
285 current
->mm
->start_data
= 0;
286 current
->mm
->end_data
= 0;
287 current
->mm
->context
.exec_fdpic_loadmap
= 0;
288 current
->mm
->context
.interp_fdpic_loadmap
= 0;
290 current
->flags
&= ~PF_FORKNOEXEC
;
293 elf_fdpic_arch_lay_out_mm(&exec_params
,
295 ¤t
->mm
->start_stack
,
296 ¤t
->mm
->start_brk
);
298 retval
= setup_arg_pages(bprm
, current
->mm
->start_stack
, executable_stack
);
300 send_sig(SIGKILL
, current
, 0);
305 /* load the executable and interpreter into memory */
306 retval
= elf_fdpic_map_file(&exec_params
, bprm
->file
, current
->mm
, "executable");
310 if (interpreter_name
) {
311 retval
= elf_fdpic_map_file(&interp_params
, interpreter
,
312 current
->mm
, "interpreter");
314 printk(KERN_ERR
"Unable to load interpreter\n");
318 allow_write_access(interpreter
);
324 if (!current
->mm
->start_brk
)
325 current
->mm
->start_brk
= current
->mm
->end_data
;
327 current
->mm
->brk
= current
->mm
->start_brk
= PAGE_ALIGN(current
->mm
->start_brk
);
330 /* create a stack and brk area big enough for everyone
331 * - the brk heap starts at the bottom and works up
332 * - the stack starts at the top and works down
334 stack_size
= (stack_size
+ PAGE_SIZE
- 1) & PAGE_MASK
;
335 if (stack_size
< PAGE_SIZE
* 2)
336 stack_size
= PAGE_SIZE
* 2;
338 down_write(¤t
->mm
->mmap_sem
);
339 current
->mm
->start_brk
= do_mmap(NULL
,
342 PROT_READ
| PROT_WRITE
| PROT_EXEC
,
343 MAP_PRIVATE
| MAP_ANON
| MAP_GROWSDOWN
,
346 if (IS_ERR((void *) current
->mm
->start_brk
)) {
347 up_write(¤t
->mm
->mmap_sem
);
348 retval
= current
->mm
->start_brk
;
349 current
->mm
->start_brk
= 0;
353 if (do_mremap(current
->mm
->start_brk
,
355 ksize((char *) current
->mm
->start_brk
),
357 ) == current
->mm
->start_brk
359 stack_size
= ksize((char *) current
->mm
->start_brk
);
360 up_write(¤t
->mm
->mmap_sem
);
362 current
->mm
->brk
= current
->mm
->start_brk
;
363 current
->mm
->context
.end_brk
= current
->mm
->start_brk
;
364 current
->mm
->context
.end_brk
+= (stack_size
> PAGE_SIZE
) ? (stack_size
- PAGE_SIZE
) : 0;
365 current
->mm
->start_stack
= current
->mm
->start_brk
+ stack_size
;
369 current
->flags
&= ~PF_FORKNOEXEC
;
370 if (create_elf_fdpic_tables(bprm
, current
->mm
, &exec_params
, &interp_params
) < 0)
373 kdebug("- start_code %lx", (long) current
->mm
->start_code
);
374 kdebug("- end_code %lx", (long) current
->mm
->end_code
);
375 kdebug("- start_data %lx", (long) current
->mm
->start_data
);
376 kdebug("- end_data %lx", (long) current
->mm
->end_data
);
377 kdebug("- start_brk %lx", (long) current
->mm
->start_brk
);
378 kdebug("- brk %lx", (long) current
->mm
->brk
);
379 kdebug("- start_stack %lx", (long) current
->mm
->start_stack
);
381 #ifdef ELF_FDPIC_PLAT_INIT
383 * The ABI may specify that certain registers be set up in special
384 * ways (on i386 %edx is the address of a DT_FINI function, for
385 * example. This macro performs whatever initialization to
386 * the regs structure is required.
388 ELF_FDPIC_PLAT_INIT(regs
,
389 exec_params
.map_addr
,
390 interp_params
.map_addr
,
391 interp_params
.dynamic_addr
?: exec_params
.dynamic_addr
395 /* everything is now ready... get the userspace context ready to roll */
397 interp_params
.entry_addr
?: exec_params
.entry_addr
,
398 current
->mm
->start_stack
);
400 if (unlikely(current
->ptrace
& PT_PTRACED
)) {
401 if (current
->ptrace
& PT_TRACE_EXEC
)
402 ptrace_notify ((PTRACE_EVENT_EXEC
<< 8) | SIGTRAP
);
404 send_sig(SIGTRAP
, current
, 0);
411 allow_write_access(interpreter
);
414 kfree(interpreter_name
);
415 kfree(exec_params
.phdrs
);
416 kfree(exec_params
.loadmap
);
417 kfree(interp_params
.phdrs
);
418 kfree(interp_params
.loadmap
);
421 /* unrecoverable error - kill the process */
423 send_sig(SIGSEGV
, current
, 0);
426 } /* end load_elf_fdpic_binary() */
428 /*****************************************************************************/
430 * present useful information to the program
432 static int create_elf_fdpic_tables(struct linux_binprm
*bprm
,
433 struct mm_struct
*mm
,
434 struct elf_fdpic_params
*exec_params
,
435 struct elf_fdpic_params
*interp_params
)
437 unsigned long sp
, csp
, nitems
;
438 elf_caddr_t
*argv
, *envp
;
439 size_t platform_len
= 0, len
;
440 char *k_platform
, *u_platform
, *p
;
444 /* we're going to shovel a whole load of stuff onto the stack */
448 sp
= mm
->start_stack
;
450 /* stack the program arguments and environment */
451 if (elf_fdpic_transfer_args_to_stack(bprm
, &sp
) < 0)
455 /* get hold of platform and hardware capabilities masks for the machine
456 * we are running on. In some cases (Sparc), this info is impossible
457 * to get, in others (i386) it is merely difficult.
460 k_platform
= ELF_PLATFORM
;
463 platform_len
= strlen(k_platform
) + 1;
465 if (__copy_to_user(u_platform
, k_platform
, platform_len
) != 0)
469 u_platform
= (char *) sp
;
471 #if defined(__i386__) && defined(CONFIG_SMP)
472 /* in some cases (e.g. Hyper-Threading), we want to avoid L1 evictions
473 * by the processes running on the same package. One thing we can do
474 * is to shuffle the initial stack for them.
476 * the conditionals here are unneeded, but kept in to make the
477 * code behaviour the same as pre change unless we have hyperthreaded
478 * processors. This keeps Mr Marcelo Person happier but should be
481 if (smp_num_siblings
> 1)
482 sp
= sp
- ((current
->pid
% 64) << 7);
487 /* stack the load map(s) */
488 len
= sizeof(struct elf32_fdpic_loadmap
);
489 len
+= sizeof(struct elf32_fdpic_loadseg
) * exec_params
->loadmap
->nsegs
;
490 sp
= (sp
- len
) & ~7UL;
491 exec_params
->map_addr
= sp
;
493 if (copy_to_user((void *) sp
, exec_params
->loadmap
, len
) != 0)
496 current
->mm
->context
.exec_fdpic_loadmap
= (unsigned long) sp
;
498 if (interp_params
->loadmap
) {
499 len
= sizeof(struct elf32_fdpic_loadmap
);
500 len
+= sizeof(struct elf32_fdpic_loadseg
) * interp_params
->loadmap
->nsegs
;
501 sp
= (sp
- len
) & ~7UL;
502 interp_params
->map_addr
= sp
;
504 if (copy_to_user((void *) sp
, interp_params
->loadmap
, len
) != 0)
507 current
->mm
->context
.interp_fdpic_loadmap
= (unsigned long) sp
;
510 /* force 16 byte _final_ alignment here for generality */
511 #define DLINFO_ITEMS 13
513 nitems
= 1 + DLINFO_ITEMS
+ (k_platform
? 1 : 0);
514 #ifdef DLINFO_ARCH_ITEMS
515 nitems
+= DLINFO_ARCH_ITEMS
;
519 sp
-= nitems
* 2 * sizeof(unsigned long);
520 sp
-= (bprm
->envc
+ 1) * sizeof(char *); /* envv[] */
521 sp
-= (bprm
->argc
+ 1) * sizeof(char *); /* argv[] */
522 sp
-= 1 * sizeof(unsigned long); /* argc */
527 /* put the ELF interpreter info on the stack */
528 #define NEW_AUX_ENT(nr, id, val) \
530 struct { unsigned long _id, _val; } *ent = (void *) csp; \
531 __put_user((id), &ent[nr]._id); \
532 __put_user((val), &ent[nr]._val); \
535 csp
-= 2 * sizeof(unsigned long);
536 NEW_AUX_ENT(0, AT_NULL
, 0);
538 csp
-= 2 * sizeof(unsigned long);
539 NEW_AUX_ENT(0, AT_PLATFORM
, (elf_addr_t
)(unsigned long) u_platform
);
542 csp
-= DLINFO_ITEMS
* 2 * sizeof(unsigned long);
543 NEW_AUX_ENT( 0, AT_HWCAP
, hwcap
);
544 NEW_AUX_ENT( 1, AT_PAGESZ
, PAGE_SIZE
);
545 NEW_AUX_ENT( 2, AT_CLKTCK
, CLOCKS_PER_SEC
);
546 NEW_AUX_ENT( 3, AT_PHDR
, exec_params
->ph_addr
);
547 NEW_AUX_ENT( 4, AT_PHENT
, sizeof(struct elf_phdr
));
548 NEW_AUX_ENT( 5, AT_PHNUM
, exec_params
->hdr
.e_phnum
);
549 NEW_AUX_ENT( 6, AT_BASE
, interp_params
->elfhdr_addr
);
550 NEW_AUX_ENT( 7, AT_FLAGS
, 0);
551 NEW_AUX_ENT( 8, AT_ENTRY
, exec_params
->entry_addr
);
552 NEW_AUX_ENT( 9, AT_UID
, (elf_addr_t
) current
->uid
);
553 NEW_AUX_ENT(10, AT_EUID
, (elf_addr_t
) current
->euid
);
554 NEW_AUX_ENT(11, AT_GID
, (elf_addr_t
) current
->gid
);
555 NEW_AUX_ENT(12, AT_EGID
, (elf_addr_t
) current
->egid
);
558 /* ARCH_DLINFO must come last so platform specific code can enforce
559 * special alignment requirements on the AUXV if necessary (eg. PPC).
565 /* allocate room for argv[] and envv[] */
566 csp
-= (bprm
->envc
+ 1) * sizeof(elf_caddr_t
);
567 envp
= (elf_caddr_t
*) csp
;
568 csp
-= (bprm
->argc
+ 1) * sizeof(elf_caddr_t
);
569 argv
= (elf_caddr_t
*) csp
;
572 csp
-= sizeof(unsigned long);
573 __put_user(bprm
->argc
, (unsigned long *) csp
);
578 /* fill in the argv[] array */
580 current
->mm
->arg_start
= bprm
->p
;
582 current
->mm
->arg_start
= current
->mm
->start_stack
- (MAX_ARG_PAGES
* PAGE_SIZE
- bprm
->p
);
585 p
= (char *) current
->mm
->arg_start
;
586 for (loop
= bprm
->argc
; loop
> 0; loop
--) {
587 __put_user((elf_caddr_t
) p
, argv
++);
588 len
= strnlen_user(p
, PAGE_SIZE
* MAX_ARG_PAGES
);
589 if (!len
|| len
> PAGE_SIZE
* MAX_ARG_PAGES
)
593 __put_user(NULL
, argv
);
594 current
->mm
->arg_end
= (unsigned long) p
;
596 /* fill in the envv[] array */
597 current
->mm
->env_start
= (unsigned long) p
;
598 for (loop
= bprm
->envc
; loop
> 0; loop
--) {
599 __put_user((elf_caddr_t
)(unsigned long) p
, envp
++);
600 len
= strnlen_user(p
, PAGE_SIZE
* MAX_ARG_PAGES
);
601 if (!len
|| len
> PAGE_SIZE
* MAX_ARG_PAGES
)
605 __put_user(NULL
, envp
);
606 current
->mm
->env_end
= (unsigned long) p
;
608 mm
->start_stack
= (unsigned long) sp
;
610 } /* end create_elf_fdpic_tables() */
612 /*****************************************************************************/
614 * transfer the program arguments and environment from the holding pages onto
618 static int elf_fdpic_transfer_args_to_stack(struct linux_binprm
*bprm
, unsigned long *_sp
)
620 unsigned long index
, stop
, sp
;
624 stop
= bprm
->p
>> PAGE_SHIFT
;
627 for (index
= MAX_ARG_PAGES
- 1; index
>= stop
; index
--) {
628 src
= kmap(bprm
->page
[index
]);
630 if (copy_to_user((void *) sp
, src
, PAGE_SIZE
) != 0)
632 kunmap(bprm
->page
[index
]);
637 *_sp
= (*_sp
- (MAX_ARG_PAGES
* PAGE_SIZE
- bprm
->p
)) & ~15;
641 } /* end elf_fdpic_transfer_args_to_stack() */
644 /*****************************************************************************/
646 * load the appropriate binary image (executable or interpreter) into memory
647 * - we assume no MMU is available
648 * - if no other PIC bits are set in params->hdr->e_flags
649 * - we assume that the LOADable segments in the binary are independently relocatable
650 * - we assume R/O executable segments are shareable
652 * - we assume the loadable parts of the image to require fixed displacement
653 * - the image is not shareable
655 static int elf_fdpic_map_file(struct elf_fdpic_params
*params
,
657 struct mm_struct
*mm
,
660 struct elf32_fdpic_loadmap
*loadmap
;
662 struct elf32_fdpic_loadseg
*mseg
;
664 struct elf32_fdpic_loadseg
*seg
;
665 struct elf32_phdr
*phdr
;
666 unsigned long load_addr
, stop
;
667 unsigned nloads
, tmp
;
671 /* allocate a load map table */
673 for (loop
= 0; loop
< params
->hdr
.e_phnum
; loop
++)
674 if (params
->phdrs
[loop
].p_type
== PT_LOAD
)
680 size
= sizeof(*loadmap
) + nloads
* sizeof(*seg
);
681 loadmap
= kmalloc(size
, GFP_KERNEL
);
685 params
->loadmap
= loadmap
;
686 memset(loadmap
, 0, size
);
688 loadmap
->version
= ELF32_FDPIC_LOADMAP_VERSION
;
689 loadmap
->nsegs
= nloads
;
691 load_addr
= params
->load_addr
;
694 /* map the requested LOADs into the memory space */
695 switch (params
->flags
& ELF_FDPIC_FLAG_ARRANGEMENT
) {
696 case ELF_FDPIC_FLAG_CONSTDISP
:
697 case ELF_FDPIC_FLAG_CONTIGUOUS
:
699 ret
= elf_fdpic_map_file_constdisp_on_uclinux(params
, file
, mm
);
705 ret
= elf_fdpic_map_file_by_direct_mmap(params
, file
, mm
);
711 /* map the entry point */
712 if (params
->hdr
.e_entry
) {
714 for (loop
= loadmap
->nsegs
; loop
> 0; loop
--, seg
++) {
715 if (params
->hdr
.e_entry
>= seg
->p_vaddr
&&
716 params
->hdr
.e_entry
< seg
->p_vaddr
+ seg
->p_memsz
719 (params
->hdr
.e_entry
- seg
->p_vaddr
) + seg
->addr
;
725 /* determine where the program header table has wound up if mapped */
726 stop
= params
->hdr
.e_phoff
+ params
->hdr
.e_phnum
* sizeof (struct elf_phdr
);
727 phdr
= params
->phdrs
;
729 for (loop
= 0; loop
< params
->hdr
.e_phnum
; loop
++, phdr
++) {
730 if (phdr
->p_type
!= PT_LOAD
)
733 if (phdr
->p_offset
> params
->hdr
.e_phoff
||
734 phdr
->p_offset
+ phdr
->p_filesz
< stop
)
738 for (loop
= loadmap
->nsegs
; loop
> 0; loop
--, seg
++) {
739 if (phdr
->p_vaddr
>= seg
->p_vaddr
&&
740 phdr
->p_vaddr
+ phdr
->p_filesz
<= seg
->p_vaddr
+ seg
->p_memsz
742 params
->ph_addr
= (phdr
->p_vaddr
- seg
->p_vaddr
) + seg
->addr
+
743 params
->hdr
.e_phoff
- phdr
->p_offset
;
750 /* determine where the dynamic section has wound up if there is one */
751 phdr
= params
->phdrs
;
752 for (loop
= 0; loop
< params
->hdr
.e_phnum
; loop
++, phdr
++) {
753 if (phdr
->p_type
!= PT_DYNAMIC
)
757 for (loop
= loadmap
->nsegs
; loop
> 0; loop
--, seg
++) {
758 if (phdr
->p_vaddr
>= seg
->p_vaddr
&&
759 phdr
->p_vaddr
+ phdr
->p_memsz
<= seg
->p_vaddr
+ seg
->p_memsz
761 params
->dynamic_addr
= (phdr
->p_vaddr
- seg
->p_vaddr
) + seg
->addr
;
763 /* check the dynamic section contains at least one item, and that
764 * the last item is a NULL entry */
765 if (phdr
->p_memsz
== 0 ||
766 phdr
->p_memsz
% sizeof(Elf32_Dyn
) != 0)
769 tmp
= phdr
->p_memsz
/ sizeof(Elf32_Dyn
);
770 if (((Elf32_Dyn
*) params
->dynamic_addr
)[tmp
- 1].d_tag
!= 0)
778 /* now elide adjacent segments in the load map on MMU linux
779 * - on uClinux the holes between may actually be filled with system stuff or stuff from
783 nloads
= loadmap
->nsegs
;
784 mseg
= loadmap
->segs
;
786 for (loop
= 1; loop
< nloads
; loop
++) {
787 /* see if we have a candidate for merging */
788 if (seg
->p_vaddr
- mseg
->p_vaddr
== seg
->addr
- mseg
->addr
) {
789 load_addr
= PAGE_ALIGN(mseg
->addr
+ mseg
->p_memsz
);
790 if (load_addr
== (seg
->addr
& PAGE_MASK
)) {
791 mseg
->p_memsz
+= load_addr
- (mseg
->addr
+ mseg
->p_memsz
);
792 mseg
->p_memsz
+= seg
->addr
& ~PAGE_MASK
;
793 mseg
->p_memsz
+= seg
->p_memsz
;
805 kdebug("Mapped Object [%s]:", what
);
806 kdebug("- elfhdr : %lx", params
->elfhdr_addr
);
807 kdebug("- entry : %lx", params
->entry_addr
);
808 kdebug("- PHDR[] : %lx", params
->ph_addr
);
809 kdebug("- DYNAMIC[]: %lx", params
->dynamic_addr
);
811 for (loop
= 0; loop
< loadmap
->nsegs
; loop
++, seg
++)
812 kdebug("- LOAD[%d] : %08x-%08x [va=%x ms=%x]",
814 seg
->addr
, seg
->addr
+ seg
->p_memsz
- 1,
815 seg
->p_vaddr
, seg
->p_memsz
);
820 printk("ELF FDPIC %s with invalid DYNAMIC section (inode=%lu)\n",
821 what
, file
->f_dentry
->d_inode
->i_ino
);
823 } /* end elf_fdpic_map_file() */
825 /*****************************************************************************/
827 * map a file with constant displacement under uClinux
830 static int elf_fdpic_map_file_constdisp_on_uclinux(struct elf_fdpic_params
*params
,
832 struct mm_struct
*mm
)
834 struct elf32_fdpic_loadseg
*seg
;
835 struct elf32_phdr
*phdr
;
836 unsigned long load_addr
, base
= ULONG_MAX
, top
= 0, maddr
= 0, mflags
;
840 load_addr
= params
->load_addr
;
841 seg
= params
->loadmap
->segs
;
843 /* determine the bounds of the contiguous overall allocation we must make */
844 phdr
= params
->phdrs
;
845 for (loop
= 0; loop
< params
->hdr
.e_phnum
; loop
++, phdr
++) {
846 if (params
->phdrs
[loop
].p_type
!= PT_LOAD
)
849 if (base
> phdr
->p_vaddr
)
850 base
= phdr
->p_vaddr
;
851 if (top
< phdr
->p_vaddr
+ phdr
->p_memsz
)
852 top
= phdr
->p_vaddr
+ phdr
->p_memsz
;
855 /* allocate one big anon block for everything */
856 mflags
= MAP_PRIVATE
;
857 if (params
->flags
& ELF_FDPIC_FLAG_EXECUTABLE
)
858 mflags
|= MAP_EXECUTABLE
;
860 down_write(&mm
->mmap_sem
);
861 maddr
= do_mmap(NULL
, load_addr
, top
- base
,
862 PROT_READ
| PROT_WRITE
| PROT_EXEC
, mflags
, 0);
863 up_write(&mm
->mmap_sem
);
864 if (IS_ERR((void *) maddr
))
868 load_addr
+= PAGE_ALIGN(top
- base
);
870 /* and then load the file segments into it */
871 phdr
= params
->phdrs
;
872 for (loop
= 0; loop
< params
->hdr
.e_phnum
; loop
++, phdr
++) {
873 if (params
->phdrs
[loop
].p_type
!= PT_LOAD
)
876 fpos
= phdr
->p_offset
;
878 seg
->addr
= maddr
+ (phdr
->p_vaddr
- base
);
879 seg
->p_vaddr
= phdr
->p_vaddr
;
880 seg
->p_memsz
= phdr
->p_memsz
;
882 ret
= file
->f_op
->read(file
, (void *) seg
->addr
, phdr
->p_filesz
, &fpos
);
886 /* map the ELF header address if in this segment */
887 if (phdr
->p_offset
== 0)
888 params
->elfhdr_addr
= seg
->addr
;
890 /* clear any space allocated but not loaded */
891 if (phdr
->p_filesz
< phdr
->p_memsz
)
892 clear_user((void *) (seg
->addr
+ phdr
->p_filesz
),
893 phdr
->p_memsz
- phdr
->p_filesz
);
896 if (phdr
->p_flags
& PF_X
) {
897 mm
->start_code
= seg
->addr
;
898 mm
->end_code
= seg
->addr
+ phdr
->p_memsz
;
900 else if (!mm
->start_data
) {
901 mm
->start_data
= seg
->addr
;
903 mm
->end_data
= seg
->addr
+ phdr
->p_memsz
;
908 if (seg
->addr
+ phdr
->p_memsz
> mm
->end_data
)
909 mm
->end_data
= seg
->addr
+ phdr
->p_memsz
;
917 } /* end elf_fdpic_map_file_constdisp_on_uclinux() */
920 /*****************************************************************************/
922 * map a binary by direct mmap() of the individual PT_LOAD segments
924 static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params
*params
,
926 struct mm_struct
*mm
)
928 struct elf32_fdpic_loadseg
*seg
;
929 struct elf32_phdr
*phdr
;
930 unsigned long load_addr
, delta_vaddr
;
933 load_addr
= params
->load_addr
;
937 seg
= params
->loadmap
->segs
;
939 /* deal with each load segment separately */
940 phdr
= params
->phdrs
;
941 for (loop
= 0; loop
< params
->hdr
.e_phnum
; loop
++, phdr
++) {
942 unsigned long maddr
, disp
, excess
, excess1
;
945 if (phdr
->p_type
!= PT_LOAD
)
948 kdebug("[LOAD] va=%lx of=%lx fs=%lx ms=%lx",
949 (unsigned long) phdr
->p_vaddr
,
950 (unsigned long) phdr
->p_offset
,
951 (unsigned long) phdr
->p_filesz
,
952 (unsigned long) phdr
->p_memsz
);
954 /* determine the mapping parameters */
955 if (phdr
->p_flags
& PF_R
) prot
|= PROT_READ
;
956 if (phdr
->p_flags
& PF_W
) prot
|= PROT_WRITE
;
957 if (phdr
->p_flags
& PF_X
) prot
|= PROT_EXEC
;
959 flags
= MAP_PRIVATE
| MAP_DENYWRITE
;
960 if (params
->flags
& ELF_FDPIC_FLAG_EXECUTABLE
)
961 flags
|= MAP_EXECUTABLE
;
965 switch (params
->flags
& ELF_FDPIC_FLAG_ARRANGEMENT
) {
966 case ELF_FDPIC_FLAG_INDEPENDENT
:
967 /* PT_LOADs are independently locatable */
970 case ELF_FDPIC_FLAG_HONOURVADDR
:
971 /* the specified virtual address must be honoured */
972 maddr
= phdr
->p_vaddr
;
976 case ELF_FDPIC_FLAG_CONSTDISP
:
977 /* constant displacement
978 * - can be mapped anywhere, but must be mapped as a unit
982 delta_vaddr
= phdr
->p_vaddr
;
986 maddr
= load_addr
+ phdr
->p_vaddr
- delta_vaddr
;
991 case ELF_FDPIC_FLAG_CONTIGUOUS
:
992 /* contiguity handled later */
1001 /* create the mapping */
1002 disp
= phdr
->p_vaddr
& ~PAGE_MASK
;
1003 down_write(&mm
->mmap_sem
);
1004 maddr
= do_mmap(file
, maddr
, phdr
->p_memsz
+ disp
, prot
, flags
,
1005 phdr
->p_offset
- disp
);
1006 up_write(&mm
->mmap_sem
);
1008 kdebug("mmap[%d] <file> sz=%lx pr=%x fl=%x of=%lx --> %08lx",
1009 loop
, phdr
->p_memsz
+ disp
, prot
, flags
, phdr
->p_offset
- disp
,
1012 if (IS_ERR((void *) maddr
))
1015 if ((params
->flags
& ELF_FDPIC_FLAG_ARRANGEMENT
) == ELF_FDPIC_FLAG_CONTIGUOUS
)
1016 load_addr
+= PAGE_ALIGN(phdr
->p_memsz
+ disp
);
1018 seg
->addr
= maddr
+ disp
;
1019 seg
->p_vaddr
= phdr
->p_vaddr
;
1020 seg
->p_memsz
= phdr
->p_memsz
;
1022 /* map the ELF header address if in this segment */
1023 if (phdr
->p_offset
== 0)
1024 params
->elfhdr_addr
= seg
->addr
;
1026 /* clear the bit between beginning of mapping and beginning of PT_LOAD */
1027 if (prot
& PROT_WRITE
&& disp
> 0) {
1028 kdebug("clear[%d] ad=%lx sz=%lx", loop
, maddr
, disp
);
1029 clear_user((void *) maddr
, disp
);
1033 /* clear any space allocated but not loaded
1034 * - on uClinux we can just clear the lot
1035 * - on MMU linux we'll get a SIGBUS beyond the last page
1036 * extant in the file
1038 excess
= phdr
->p_memsz
- phdr
->p_filesz
;
1039 excess1
= PAGE_SIZE
- ((maddr
+ phdr
->p_filesz
) & ~PAGE_MASK
);
1043 if (excess
> excess1
) {
1044 unsigned long xaddr
= maddr
+ phdr
->p_filesz
+ excess1
;
1045 unsigned long xmaddr
;
1047 flags
|= MAP_FIXED
| MAP_ANONYMOUS
;
1048 down_write(&mm
->mmap_sem
);
1049 xmaddr
= do_mmap(NULL
, xaddr
, excess
- excess1
, prot
, flags
, 0);
1050 up_write(&mm
->mmap_sem
);
1052 kdebug("mmap[%d] <anon>"
1053 " ad=%lx sz=%lx pr=%x fl=%x of=0 --> %08lx",
1054 loop
, xaddr
, excess
- excess1
, prot
, flags
, xmaddr
);
1056 if (xmaddr
!= xaddr
)
1060 if (prot
& PROT_WRITE
&& excess1
> 0) {
1061 kdebug("clear[%d] ad=%lx sz=%lx",
1062 loop
, maddr
+ phdr
->p_filesz
, excess1
);
1063 clear_user((void *) maddr
+ phdr
->p_filesz
, excess1
);
1068 kdebug("clear[%d] ad=%lx sz=%lx",
1069 loop
, maddr
+ phdr
->p_filesz
, excess
);
1070 clear_user((void *) maddr
+ phdr
->p_filesz
, excess
);
1075 if (phdr
->p_flags
& PF_X
) {
1076 mm
->start_code
= maddr
;
1077 mm
->end_code
= maddr
+ phdr
->p_memsz
;
1079 else if (!mm
->start_data
) {
1080 mm
->start_data
= maddr
;
1081 mm
->end_data
= maddr
+ phdr
->p_memsz
;
1089 } /* end elf_fdpic_map_file_by_direct_mmap() */