2 * a.out loader for x86-64
4 * Copyright (C) 1991, 1992, 1996 Linus Torvalds
5 * Hacked together by Andi Kleen
8 #include <linux/module.h>
10 #include <linux/time.h>
11 #include <linux/kernel.h>
13 #include <linux/mman.h>
14 #include <linux/a.out.h>
15 #include <linux/errno.h>
16 #include <linux/signal.h>
17 #include <linux/string.h>
19 #include <linux/file.h>
20 #include <linux/stat.h>
21 #include <linux/fcntl.h>
22 #include <linux/ptrace.h>
23 #include <linux/user.h>
24 #include <linux/slab.h>
25 #include <linux/binfmts.h>
26 #include <linux/personality.h>
27 #include <linux/init.h>
29 #include <asm/system.h>
30 #include <asm/uaccess.h>
31 #include <asm/pgalloc.h>
32 #include <asm/cacheflush.h>
33 #include <asm/user32.h>
36 #undef CORE_DUMP /* probably broken */
38 extern int ia32_setup_arg_pages(struct linux_binprm
*bprm
, int exec_stack
);
40 static int load_aout_binary(struct linux_binprm
*, struct pt_regs
* regs
);
41 static int load_aout_library(struct file
*);
44 static int aout_core_dump(long signr
, struct pt_regs
* regs
, struct file
*file
);
47 * fill in the user structure for a core dump..
49 static void dump_thread32(struct pt_regs
* regs
, struct user32
* dump
)
53 /* changed the size calculations - should hopefully work better. lbt */
56 dump
->start_stack
= regs
->rsp
& ~(PAGE_SIZE
- 1);
57 dump
->u_tsize
= ((unsigned long) current
->mm
->end_code
) >> PAGE_SHIFT
;
58 dump
->u_dsize
= ((unsigned long) (current
->mm
->brk
+ (PAGE_SIZE
-1))) >> PAGE_SHIFT
;
59 dump
->u_dsize
-= dump
->u_tsize
;
61 dump
->u_debugreg
[0] = current
->thread
.debugreg0
;
62 dump
->u_debugreg
[1] = current
->thread
.debugreg1
;
63 dump
->u_debugreg
[2] = current
->thread
.debugreg2
;
64 dump
->u_debugreg
[3] = current
->thread
.debugreg3
;
65 dump
->u_debugreg
[4] = 0;
66 dump
->u_debugreg
[5] = 0;
67 dump
->u_debugreg
[6] = current
->thread
.debugreg6
;
68 dump
->u_debugreg
[7] = current
->thread
.debugreg7
;
70 if (dump
->start_stack
< 0xc0000000)
71 dump
->u_ssize
= ((unsigned long) (0xc0000000 - dump
->start_stack
)) >> PAGE_SHIFT
;
73 dump
->regs
.ebx
= regs
->rbx
;
74 dump
->regs
.ecx
= regs
->rcx
;
75 dump
->regs
.edx
= regs
->rdx
;
76 dump
->regs
.esi
= regs
->rsi
;
77 dump
->regs
.edi
= regs
->rdi
;
78 dump
->regs
.ebp
= regs
->rbp
;
79 dump
->regs
.eax
= regs
->rax
;
80 dump
->regs
.ds
= current
->thread
.ds
;
81 dump
->regs
.es
= current
->thread
.es
;
82 asm("movl %%fs,%0" : "=r" (fs
)); dump
->regs
.fs
= fs
;
83 asm("movl %%gs,%0" : "=r" (gs
)); dump
->regs
.gs
= gs
;
84 dump
->regs
.orig_eax
= regs
->orig_rax
;
85 dump
->regs
.eip
= regs
->rip
;
86 dump
->regs
.cs
= regs
->cs
;
87 dump
->regs
.eflags
= regs
->eflags
;
88 dump
->regs
.esp
= regs
->rsp
;
89 dump
->regs
.ss
= regs
->ss
;
94 dump
->u_fpvalid
= dump_fpu (regs
, &dump
->i387
);
100 static struct linux_binfmt aout_format
= {
101 .module
= THIS_MODULE
,
102 .load_binary
= load_aout_binary
,
103 .load_shlib
= load_aout_library
,
105 .core_dump
= aout_core_dump
,
107 .min_coredump
= PAGE_SIZE
110 static void set_brk(unsigned long start
, unsigned long end
)
112 start
= PAGE_ALIGN(start
);
113 end
= PAGE_ALIGN(end
);
116 do_brk(start
, end
- start
);
121 * These are the only things you should do on a core-file: use only these
122 * macros to write out all the necessary info.
125 static int dump_write(struct file
*file
, const void *addr
, int nr
)
127 return file
->f_op
->write(file
, addr
, nr
, &file
->f_pos
) == nr
;
130 #define DUMP_WRITE(addr, nr) \
131 if (!dump_write(file, (void *)(addr), (nr))) \
134 #define DUMP_SEEK(offset) \
135 if (file->f_op->llseek) { \
136 if (file->f_op->llseek(file,(offset),0) != (offset)) \
138 } else file->f_pos = (offset)
141 * Routine writes a core dump image in the current directory.
142 * Currently only a stub-function.
144 * Note that setuid/setgid files won't make a core-dump if the uid/gid
145 * changed due to the set[u|g]id. It's enforced by the "current->mm->dumpable"
146 * field, which also makes sure the core-dumps won't be recursive if the
147 * dumping of the process results in another error..
150 static int aout_core_dump(long signr
, struct pt_regs
* regs
, struct file
*file
)
154 unsigned long dump_start
, dump_size
;
156 # define START_DATA(u) (u.u_tsize << PAGE_SHIFT)
157 # define START_STACK(u) (u.start_stack)
162 current
->flags
|= PF_DUMPCORE
;
163 strncpy(dump
.u_comm
, current
->comm
, sizeof(current
->comm
));
164 dump
.u_ar0
= (u32
)(((unsigned long)(&dump
.regs
)) - ((unsigned long)(&dump
)));
166 dump_thread32(regs
, &dump
);
168 /* If the size of the dump file exceeds the rlimit, then see what would happen
169 if we wrote the stack, but not the data area. */
170 if ((dump
.u_dsize
+dump
.u_ssize
+1) * PAGE_SIZE
>
171 current
->rlim
[RLIMIT_CORE
].rlim_cur
)
174 /* Make sure we have enough room to write the stack and data areas. */
175 if ((dump
.u_ssize
+1) * PAGE_SIZE
>
176 current
->rlim
[RLIMIT_CORE
].rlim_cur
)
179 /* make sure we actually have a data and stack area to dump */
181 if (verify_area(VERIFY_READ
, (void *) (unsigned long)START_DATA(dump
), dump
.u_dsize
<< PAGE_SHIFT
))
183 if (verify_area(VERIFY_READ
, (void *) (unsigned long)START_STACK(dump
), dump
.u_ssize
<< PAGE_SHIFT
))
188 DUMP_WRITE(&dump
,sizeof(dump
));
189 /* Now dump all of the user data. Include malloced stuff as well */
190 DUMP_SEEK(PAGE_SIZE
);
191 /* now we start writing out the user space info */
193 /* Dump the data area */
194 if (dump
.u_dsize
!= 0) {
195 dump_start
= START_DATA(dump
);
196 dump_size
= dump
.u_dsize
<< PAGE_SHIFT
;
197 DUMP_WRITE(dump_start
,dump_size
);
199 /* Now prepare to dump the stack area */
200 if (dump
.u_ssize
!= 0) {
201 dump_start
= START_STACK(dump
);
202 dump_size
= dump
.u_ssize
<< PAGE_SHIFT
;
203 DUMP_WRITE(dump_start
,dump_size
);
205 /* Finally dump the task struct. Not be used by gdb, but could be useful */
207 DUMP_WRITE(current
,sizeof(*current
));
215 * create_aout_tables() parses the env- and arg-strings in new user
216 * memory and creates the pointer tables from them, and puts their
217 * addresses on the "stack", returning the new stack pointer value.
219 static u32 __user
*create_aout_tables(char __user
*p
, struct linux_binprm
*bprm
)
224 int argc
= bprm
->argc
;
225 int envc
= bprm
->envc
;
227 sp
= (u32 __user
*) ((-(unsigned long)sizeof(u32
)) & (unsigned long) p
);
232 put_user((unsigned long) envp
,--sp
);
233 put_user((unsigned long) argv
,--sp
);
235 current
->mm
->arg_start
= (unsigned long) p
;
238 put_user((u32
)(unsigned long)p
,argv
++);
244 current
->mm
->arg_end
= current
->mm
->env_start
= (unsigned long) p
;
247 put_user((u32
)(unsigned long)p
,envp
++);
253 current
->mm
->env_end
= (unsigned long) p
;
258 * These are the functions used to load a.out style executables and shared
259 * libraries. There is no binary dependent code anywhere else.
262 static int load_aout_binary(struct linux_binprm
* bprm
, struct pt_regs
* regs
)
266 unsigned long fd_offset
;
270 ex
= *((struct exec
*) bprm
->buf
); /* exec-header */
271 if ((N_MAGIC(ex
) != ZMAGIC
&& N_MAGIC(ex
) != OMAGIC
&&
272 N_MAGIC(ex
) != QMAGIC
&& N_MAGIC(ex
) != NMAGIC
) ||
273 N_TRSIZE(ex
) || N_DRSIZE(ex
) ||
274 i_size_read(bprm
->file
->f_dentry
->d_inode
) < ex
.a_text
+ex
.a_data
+N_SYMSIZE(ex
)+N_TXTOFF(ex
)) {
278 fd_offset
= N_TXTOFF(ex
);
280 /* Check initial limits. This avoids letting people circumvent
281 * size limits imposed on them by creating programs with large
282 * arrays in the data or bss.
284 rlim
= current
->rlim
[RLIMIT_DATA
].rlim_cur
;
285 if (rlim
>= RLIM_INFINITY
)
287 if (ex
.a_data
+ ex
.a_bss
> rlim
)
290 /* Flush all traces of the currently running executable */
291 retval
= flush_old_exec(bprm
);
295 regs
->cs
= __USER32_CS
;
296 regs
->r8
= regs
->r9
= regs
->r10
= regs
->r11
= regs
->r12
=
297 regs
->r13
= regs
->r14
= regs
->r15
= 0;
299 /* OK, This is the point of no return */
300 set_personality(PER_LINUX
);
301 set_thread_flag(TIF_IA32
);
302 clear_thread_flag(TIF_ABI_PENDING
);
304 current
->mm
->end_code
= ex
.a_text
+
305 (current
->mm
->start_code
= N_TXTADDR(ex
));
306 current
->mm
->end_data
= ex
.a_data
+
307 (current
->mm
->start_data
= N_DATADDR(ex
));
308 current
->mm
->brk
= ex
.a_bss
+
309 (current
->mm
->start_brk
= N_BSSADDR(ex
));
310 current
->mm
->free_area_cache
= TASK_UNMAPPED_BASE
;
312 current
->mm
->rss
= 0;
313 current
->mm
->mmap
= NULL
;
315 current
->flags
&= ~PF_FORKNOEXEC
;
317 if (N_MAGIC(ex
) == OMAGIC
) {
318 unsigned long text_addr
, map_size
;
321 text_addr
= N_TXTADDR(ex
);
324 map_size
= ex
.a_text
+ex
.a_data
;
326 error
= do_brk(text_addr
& PAGE_MASK
, map_size
);
327 if (error
!= (text_addr
& PAGE_MASK
)) {
328 send_sig(SIGKILL
, current
, 0);
332 error
= bprm
->file
->f_op
->read(bprm
->file
, (char *)text_addr
,
333 ex
.a_text
+ex
.a_data
, &pos
);
334 if ((signed long)error
< 0) {
335 send_sig(SIGKILL
, current
, 0);
339 flush_icache_range(text_addr
, text_addr
+ex
.a_text
+ex
.a_data
);
342 static unsigned long error_time
, error_time2
;
343 if ((ex
.a_text
& 0xfff || ex
.a_data
& 0xfff) &&
344 (N_MAGIC(ex
) != NMAGIC
) && (jiffies
-error_time2
) > 5*HZ
)
346 printk(KERN_NOTICE
"executable not page aligned\n");
347 error_time2
= jiffies
;
350 if ((fd_offset
& ~PAGE_MASK
) != 0 &&
351 (jiffies
-error_time
) > 5*HZ
)
354 "fd_offset is not page aligned. Please convert program: %s\n",
355 bprm
->file
->f_dentry
->d_name
.name
);
356 error_time
= jiffies
;
360 if (!bprm
->file
->f_op
->mmap
||((fd_offset
& ~PAGE_MASK
) != 0)) {
361 loff_t pos
= fd_offset
;
362 do_brk(N_TXTADDR(ex
), ex
.a_text
+ex
.a_data
);
363 bprm
->file
->f_op
->read(bprm
->file
,(char *)N_TXTADDR(ex
),
364 ex
.a_text
+ex
.a_data
, &pos
);
365 flush_icache_range((unsigned long) N_TXTADDR(ex
),
366 (unsigned long) N_TXTADDR(ex
) +
367 ex
.a_text
+ex
.a_data
);
371 down_write(¤t
->mm
->mmap_sem
);
372 error
= do_mmap(bprm
->file
, N_TXTADDR(ex
), ex
.a_text
,
373 PROT_READ
| PROT_EXEC
,
374 MAP_FIXED
| MAP_PRIVATE
| MAP_DENYWRITE
| MAP_EXECUTABLE
| MAP_32BIT
,
376 up_write(¤t
->mm
->mmap_sem
);
378 if (error
!= N_TXTADDR(ex
)) {
379 send_sig(SIGKILL
, current
, 0);
383 down_write(¤t
->mm
->mmap_sem
);
384 error
= do_mmap(bprm
->file
, N_DATADDR(ex
), ex
.a_data
,
385 PROT_READ
| PROT_WRITE
| PROT_EXEC
,
386 MAP_FIXED
| MAP_PRIVATE
| MAP_DENYWRITE
| MAP_EXECUTABLE
| MAP_32BIT
,
387 fd_offset
+ ex
.a_text
);
388 up_write(¤t
->mm
->mmap_sem
);
389 if (error
!= N_DATADDR(ex
)) {
390 send_sig(SIGKILL
, current
, 0);
395 set_binfmt(&aout_format
);
397 set_brk(current
->mm
->start_brk
, current
->mm
->brk
);
399 retval
= ia32_setup_arg_pages(bprm
, EXSTACK_DEFAULT
);
401 /* Someone check-me: is this error path enough? */
402 send_sig(SIGKILL
, current
, 0);
406 current
->mm
->start_stack
=
407 (unsigned long)create_aout_tables((char __user
*)bprm
->p
, bprm
);
409 asm volatile("movl %0,%%fs" :: "r" (0)); \
410 asm volatile("movl %0,%%es; movl %0,%%ds": :"r" (__USER32_DS
));
412 (regs
)->rip
= ex
.a_entry
;
413 (regs
)->rsp
= current
->mm
->start_stack
;
414 (regs
)->eflags
= 0x200;
415 (regs
)->cs
= __USER32_CS
;
416 (regs
)->ss
= __USER32_DS
;
418 if (unlikely(current
->ptrace
& PT_PTRACED
)) {
419 if (current
->ptrace
& PT_TRACE_EXEC
)
420 ptrace_notify ((PTRACE_EVENT_EXEC
<< 8) | SIGTRAP
);
422 send_sig(SIGTRAP
, current
, 0);
427 static int load_aout_library(struct file
*file
)
429 struct inode
* inode
;
430 unsigned long bss
, start_addr
, len
;
435 inode
= file
->f_dentry
->d_inode
;
438 error
= kernel_read(file
, 0, (char *) &ex
, sizeof(ex
));
439 if (error
!= sizeof(ex
))
442 /* We come in here for the regular a.out style of shared libraries */
443 if ((N_MAGIC(ex
) != ZMAGIC
&& N_MAGIC(ex
) != QMAGIC
) || N_TRSIZE(ex
) ||
444 N_DRSIZE(ex
) || ((ex
.a_entry
& 0xfff) && N_MAGIC(ex
) == ZMAGIC
) ||
445 i_size_read(inode
) < ex
.a_text
+ex
.a_data
+N_SYMSIZE(ex
)+N_TXTOFF(ex
)) {
452 /* For QMAGIC, the starting address is 0x20 into the page. We mask
453 this off to get the starting address for the page */
455 start_addr
= ex
.a_entry
& 0xfffff000;
457 if ((N_TXTOFF(ex
) & ~PAGE_MASK
) != 0) {
458 loff_t pos
= N_TXTOFF(ex
);
461 static unsigned long error_time
;
462 if ((jiffies
-error_time
) > 5*HZ
)
465 "N_TXTOFF is not page aligned. Please convert library: %s\n",
466 file
->f_dentry
->d_name
.name
);
467 error_time
= jiffies
;
471 do_brk(start_addr
, ex
.a_text
+ ex
.a_data
+ ex
.a_bss
);
473 file
->f_op
->read(file
, (char *)start_addr
,
474 ex
.a_text
+ ex
.a_data
, &pos
);
475 flush_icache_range((unsigned long) start_addr
,
476 (unsigned long) start_addr
+ ex
.a_text
+ ex
.a_data
);
481 /* Now use mmap to map the library into memory. */
482 down_write(¤t
->mm
->mmap_sem
);
483 error
= do_mmap(file
, start_addr
, ex
.a_text
+ ex
.a_data
,
484 PROT_READ
| PROT_WRITE
| PROT_EXEC
,
485 MAP_FIXED
| MAP_PRIVATE
| MAP_DENYWRITE
| MAP_32BIT
,
487 up_write(¤t
->mm
->mmap_sem
);
489 if (error
!= start_addr
)
492 len
= PAGE_ALIGN(ex
.a_text
+ ex
.a_data
);
493 bss
= ex
.a_text
+ ex
.a_data
+ ex
.a_bss
;
495 error
= do_brk(start_addr
+ len
, bss
- len
);
497 if (error
!= start_addr
+ len
)
505 static int __init
init_aout_binfmt(void)
507 return register_binfmt(&aout_format
);
510 static void __exit
exit_aout_binfmt(void)
512 unregister_binfmt(&aout_format
);
515 module_init(init_aout_binfmt
);
516 module_exit(exit_aout_binfmt
);
517 MODULE_LICENSE("GPL");