2 * linux/fs/binfmt_aout.c
4 * Copyright (C) 1991, 1992, 1996 Linus Torvalds
7 #include <linux/module.h>
9 #include <linux/sched.h>
10 #include <linux/kernel.h>
12 #include <linux/mman.h>
13 #include <linux/a.out.h>
14 #include <linux/errno.h>
15 #include <linux/signal.h>
16 #include <linux/string.h>
18 #include <linux/file.h>
19 #include <linux/stat.h>
20 #include <linux/fcntl.h>
21 #include <linux/ptrace.h>
22 #include <linux/user.h>
23 #include <linux/malloc.h>
24 #include <linux/binfmts.h>
25 #include <linux/personality.h>
26 #include <linux/init.h>
28 #include <asm/system.h>
29 #include <asm/uaccess.h>
30 #include <asm/pgtable.h>
32 static int load_aout_binary(struct linux_binprm
*, struct pt_regs
* regs
);
33 static int load_aout_library(int fd
);
34 static int aout_core_dump(long signr
, struct pt_regs
* regs
);
36 extern void dump_thread(struct pt_regs
*, struct user
*);
38 static struct linux_binfmt aout_format
= {
40 NULL
, NULL
, load_aout_binary
, load_aout_library
, aout_core_dump
42 NULL
, &__this_module
, load_aout_binary
, load_aout_library
, aout_core_dump
46 static void set_brk(unsigned long start
, unsigned long end
)
48 start
= PAGE_ALIGN(start
);
49 end
= PAGE_ALIGN(end
);
52 do_mmap(NULL
, start
, end
- start
,
53 PROT_READ
| PROT_WRITE
| PROT_EXEC
,
54 MAP_FIXED
| MAP_PRIVATE
, 0);
58 * These are the only things you should do on a core-file: use only these
59 * macros to write out all the necessary info.
61 #define DUMP_WRITE(addr,nr) \
62 while (file.f_op->write(&file,(char *)(addr),(nr),&file.f_pos) != (nr)) goto close_coredump
64 #define DUMP_SEEK(offset) \
65 if (file.f_op->llseek) { \
66 if (file.f_op->llseek(&file,(offset),0) != (offset)) \
67 goto close_coredump; \
68 } else file.f_pos = (offset)
71 * Routine writes a core dump image in the current directory.
72 * Currently only a stub-function.
74 * Note that setuid/setgid files won't make a core-dump if the uid/gid
75 * changed due to the set[u|g]id. It's enforced by the "current->dumpable"
76 * field, which also makes sure the core-dumps won't be recursive if the
77 * dumping of the process results in another error..
81 do_aout_core_dump(long signr
, struct pt_regs
* regs
)
83 struct dentry
* dentry
= NULL
;
84 struct inode
* inode
= NULL
;
88 char corefile
[6+sizeof(current
->comm
)];
89 unsigned long dump_start
, dump_size
;
91 #if defined(__alpha__)
92 # define START_DATA(u) (u.start_data)
93 #elif defined(__sparc__)
94 # define START_DATA(u) (u.u_tsize)
95 #elif defined(__i386__) || defined(__mc68000__)
96 # define START_DATA(u) (u.u_tsize << PAGE_SHIFT)
99 # define START_STACK(u) ((regs->u_regs[UREG_FP]) & ~(PAGE_SIZE - 1))
101 # define START_STACK(u) (u.start_stack)
104 if (!current
->dumpable
|| atomic_read(¤t
->mm
->count
) != 1)
106 current
->dumpable
= 0;
108 /* See if we have enough room to write the upage. */
109 if (current
->rlim
[RLIMIT_CORE
].rlim_cur
< PAGE_SIZE
)
113 memcpy(corefile
,"core.",5);
115 memcpy(corefile
+5,current
->comm
,sizeof(current
->comm
));
119 dentry
= open_namei(corefile
,O_CREAT
| 2 | O_TRUNC
| O_NOFOLLOW
, 0600);
120 if (IS_ERR(dentry
)) {
124 inode
= dentry
->d_inode
;
125 if (!S_ISREG(inode
->i_mode
))
127 if (!inode
->i_op
|| !inode
->i_op
->default_file_ops
)
129 if (get_write_access(inode
))
131 if (init_private_file(&file
, dentry
, 3))
132 goto end_coredump_write
;
133 if (!file
.f_op
->write
)
136 current
->flags
|= PF_DUMPCORE
;
137 strncpy(dump
.u_comm
, current
->comm
, sizeof(current
->comm
));
139 dump
.u_ar0
= (void *)(((unsigned long)(&dump
.regs
)) - ((unsigned long)(&dump
)));
142 dump_thread(regs
, &dump
);
144 /* If the size of the dump file exceeds the rlimit, then see what would happen
145 if we wrote the stack, but not the data area. */
147 if ((dump
.u_dsize
+dump
.u_ssize
) >
148 current
->rlim
[RLIMIT_CORE
].rlim_cur
)
151 if ((dump
.u_dsize
+dump
.u_ssize
+1) * PAGE_SIZE
>
152 current
->rlim
[RLIMIT_CORE
].rlim_cur
)
156 /* Make sure we have enough room to write the stack and data areas. */
159 current
->rlim
[RLIMIT_CORE
].rlim_cur
)
162 if ((dump
.u_ssize
+1) * PAGE_SIZE
>
163 current
->rlim
[RLIMIT_CORE
].rlim_cur
)
167 /* make sure we actually have a data and stack area to dump */
170 if (verify_area(VERIFY_READ
, (void *) START_DATA(dump
), dump
.u_dsize
))
172 if (verify_area(VERIFY_READ
, (void *) START_STACK(dump
), dump
.u_ssize
))
175 if (verify_area(VERIFY_READ
, (void *) START_DATA(dump
), dump
.u_dsize
<< PAGE_SHIFT
))
177 if (verify_area(VERIFY_READ
, (void *) START_STACK(dump
), dump
.u_ssize
<< PAGE_SHIFT
))
183 DUMP_WRITE(&dump
,sizeof(dump
));
184 /* Now dump all of the user data. Include malloced stuff as well */
186 DUMP_SEEK(PAGE_SIZE
);
188 /* now we start writing out the user space info */
190 /* Dump the data area */
191 if (dump
.u_dsize
!= 0) {
192 dump_start
= START_DATA(dump
);
194 dump_size
= dump
.u_dsize
;
196 dump_size
= dump
.u_dsize
<< PAGE_SHIFT
;
198 DUMP_WRITE(dump_start
,dump_size
);
200 /* Now prepare to dump the stack area */
201 if (dump
.u_ssize
!= 0) {
202 dump_start
= START_STACK(dump
);
204 dump_size
= dump
.u_ssize
;
206 dump_size
= dump
.u_ssize
<< PAGE_SHIFT
;
208 DUMP_WRITE(dump_start
,dump_size
);
210 /* Finally dump the task struct. Not be used by gdb, but could be useful */
212 DUMP_WRITE(current
,sizeof(*current
));
214 if (file
.f_op
->release
)
215 file
.f_op
->release(inode
,&file
);
217 put_write_access(inode
);
225 aout_core_dump(long signr
, struct pt_regs
* regs
)
230 retval
= do_aout_core_dump(signr
, regs
);
236 * create_aout_tables() parses the env- and arg-strings in new user
237 * memory and creates the pointer tables from them, and puts their
238 * addresses on the "stack", returning the new stack pointer value.
240 static unsigned long * create_aout_tables(char * p
, struct linux_binprm
* bprm
)
244 int argc
= bprm
->argc
;
245 int envc
= bprm
->envc
;
247 sp
= (unsigned long *) ((-(unsigned long)sizeof(char *)) & (unsigned long) p
);
249 /* This imposes the proper stack alignment for a new process. */
250 sp
= (unsigned long *) (((unsigned long) sp
) & ~7);
251 if ((envc
+argc
+3)&1) --sp
;
254 /* whee.. test-programs are so much fun. */
259 put_user(0x3eb, --sp
);
260 put_user(bprm
->loader
, --sp
);
261 put_user(0x3ea, --sp
);
263 put_user(bprm
->exec
, --sp
);
264 put_user(0x3e9, --sp
);
270 #if defined(__i386__) || defined(__mc68000__)
271 put_user((unsigned long) envp
,--sp
);
272 put_user((unsigned long) argv
,--sp
);
275 current
->mm
->arg_start
= (unsigned long) p
;
284 current
->mm
->arg_end
= current
->mm
->env_start
= (unsigned long) p
;
293 current
->mm
->env_end
= (unsigned long) p
;
298 * These are the functions used to load a.out style executables and shared
299 * libraries. There is no binary dependent code anywhere else.
302 static inline int do_load_aout_binary(struct linux_binprm
* bprm
, struct pt_regs
* regs
)
308 unsigned long p
= bprm
->p
;
309 unsigned long fd_offset
;
313 ex
= *((struct exec
*) bprm
->buf
); /* exec-header */
314 if ((N_MAGIC(ex
) != ZMAGIC
&& N_MAGIC(ex
) != OMAGIC
&&
315 N_MAGIC(ex
) != QMAGIC
&& N_MAGIC(ex
) != NMAGIC
) ||
316 N_TRSIZE(ex
) || N_DRSIZE(ex
) ||
317 bprm
->dentry
->d_inode
->i_size
< ex
.a_text
+ex
.a_data
+N_SYMSIZE(ex
)+N_TXTOFF(ex
)) {
321 fd_offset
= N_TXTOFF(ex
);
324 if (N_MAGIC(ex
) == ZMAGIC
&& fd_offset
!= BLOCK_SIZE
) {
325 printk(KERN_NOTICE
"N_TXTOFF != BLOCK_SIZE. See a.out.h.\n");
329 if (N_MAGIC(ex
) == ZMAGIC
&& ex
.a_text
&&
330 (fd_offset
< bprm
->dentry
->d_inode
->i_sb
->s_blocksize
)) {
331 printk(KERN_NOTICE
"N_TXTOFF < BLOCK_SIZE. Please convert binary.\n");
336 /* Check initial limits. This avoids letting people circumvent
337 * size limits imposed on them by creating programs with large
338 * arrays in the data or bss.
340 rlim
= current
->rlim
[RLIMIT_DATA
].rlim_cur
;
341 if (rlim
>= RLIM_INFINITY
)
343 if (ex
.a_data
+ ex
.a_bss
> rlim
)
346 /* Flush all traces of the currently running executable */
347 retval
= flush_old_exec(bprm
);
351 /* OK, This is the point of no return */
352 current
->personality
= PER_LINUX
;
354 #if defined(__sparc__) && !defined(__sparc_v9__)
355 memcpy(¤t
->tss
.core_exec
, &ex
, sizeof(struct exec
));
358 current
->mm
->end_code
= ex
.a_text
+
359 (current
->mm
->start_code
= N_TXTADDR(ex
));
360 current
->mm
->end_data
= ex
.a_data
+
361 (current
->mm
->start_data
= N_DATADDR(ex
));
362 current
->mm
->brk
= ex
.a_bss
+
363 (current
->mm
->start_brk
= N_BSSADDR(ex
));
365 current
->mm
->rss
= 0;
366 current
->mm
->mmap
= NULL
;
368 current
->flags
&= ~PF_FORKNOEXEC
;
370 if (N_MAGIC(ex
) == NMAGIC
) {
371 /* Fuck me plenty... */
372 error
= do_mmap(NULL
, N_TXTADDR(ex
), ex
.a_text
,
373 PROT_READ
|PROT_WRITE
|PROT_EXEC
,
374 MAP_FIXED
|MAP_PRIVATE
, 0);
375 read_exec(bprm
->dentry
, fd_offset
, (char *) N_TXTADDR(ex
),
377 error
= do_mmap(NULL
, N_DATADDR(ex
), ex
.a_data
,
378 PROT_READ
|PROT_WRITE
|PROT_EXEC
,
379 MAP_FIXED
|MAP_PRIVATE
, 0);
380 read_exec(bprm
->dentry
, fd_offset
+ ex
.a_text
, (char *) N_DATADDR(ex
),
386 if (N_MAGIC(ex
) == OMAGIC
) {
387 #if defined(__alpha__) || defined(__sparc__)
388 do_mmap(NULL
, N_TXTADDR(ex
) & PAGE_MASK
,
389 ex
.a_text
+ex
.a_data
+ PAGE_SIZE
- 1,
390 PROT_READ
|PROT_WRITE
|PROT_EXEC
,
391 MAP_FIXED
|MAP_PRIVATE
, 0);
392 read_exec(bprm
->dentry
, fd_offset
, (char *) N_TXTADDR(ex
),
393 ex
.a_text
+ex
.a_data
, 0);
395 do_mmap(NULL
, 0, ex
.a_text
+ex
.a_data
,
396 PROT_READ
|PROT_WRITE
|PROT_EXEC
,
397 MAP_FIXED
|MAP_PRIVATE
, 0);
398 read_exec(bprm
->dentry
, 32, (char *) 0, ex
.a_text
+ex
.a_data
, 0);
400 flush_icache_range((unsigned long) 0,
401 (unsigned long) ex
.a_text
+ex
.a_data
);
403 if ((ex
.a_text
& 0xfff || ex
.a_data
& 0xfff) &&
404 (N_MAGIC(ex
) != NMAGIC
))
405 printk(KERN_NOTICE
"executable not page aligned\n");
407 fd
= open_dentry(bprm
->dentry
, O_RDONLY
);
412 if (!file
->f_op
|| !file
->f_op
->mmap
) {
414 do_mmap(NULL
, 0, ex
.a_text
+ex
.a_data
,
415 PROT_READ
|PROT_WRITE
|PROT_EXEC
,
416 MAP_FIXED
|MAP_PRIVATE
, 0);
417 read_exec(bprm
->dentry
, fd_offset
,
418 (char *) N_TXTADDR(ex
), ex
.a_text
+ex
.a_data
, 0);
419 flush_icache_range((unsigned long) N_TXTADDR(ex
),
420 (unsigned long) N_TXTADDR(ex
) +
421 ex
.a_text
+ex
.a_data
);
425 error
= do_mmap(file
, N_TXTADDR(ex
), ex
.a_text
,
426 PROT_READ
| PROT_EXEC
,
427 MAP_FIXED
| MAP_PRIVATE
| MAP_DENYWRITE
| MAP_EXECUTABLE
,
430 if (error
!= N_TXTADDR(ex
)) {
432 send_sig(SIGKILL
, current
, 0);
436 error
= do_mmap(file
, N_DATADDR(ex
), ex
.a_data
,
437 PROT_READ
| PROT_WRITE
| PROT_EXEC
,
438 MAP_FIXED
| MAP_PRIVATE
| MAP_DENYWRITE
| MAP_EXECUTABLE
,
439 fd_offset
+ ex
.a_text
);
441 if (error
!= N_DATADDR(ex
)) {
442 send_sig(SIGKILL
, current
, 0);
447 if (current
->exec_domain
&& current
->exec_domain
->module
)
448 __MOD_DEC_USE_COUNT(current
->exec_domain
->module
);
449 if (current
->binfmt
&& current
->binfmt
->module
)
450 __MOD_DEC_USE_COUNT(current
->binfmt
->module
);
451 current
->exec_domain
= lookup_exec_domain(current
->personality
);
452 current
->binfmt
= &aout_format
;
453 if (current
->exec_domain
&& current
->exec_domain
->module
)
454 __MOD_INC_USE_COUNT(current
->exec_domain
->module
);
455 if (current
->binfmt
&& current
->binfmt
->module
)
456 __MOD_INC_USE_COUNT(current
->binfmt
->module
);
458 set_brk(current
->mm
->start_brk
, current
->mm
->brk
);
460 p
= setup_arg_pages(p
, bprm
);
462 p
= (unsigned long) create_aout_tables((char *)p
, bprm
);
463 current
->mm
->start_stack
= p
;
465 regs
->gp
= ex
.a_gpvalue
;
467 start_thread(regs
, ex
.a_entry
, p
);
468 if (current
->flags
& PF_PTRACED
)
469 send_sig(SIGTRAP
, current
, 0);
475 load_aout_binary(struct linux_binprm
* bprm
, struct pt_regs
* regs
)
480 retval
= do_load_aout_binary(bprm
, regs
);
486 do_load_aout_library(int fd
)
489 struct inode
* inode
;
490 unsigned long bss
, start_addr
, len
;
502 inode
= file
->f_dentry
->d_inode
;
505 /* N.B. Save current fs? */
507 error
= file
->f_op
->read(file
, (char *) &ex
, sizeof(ex
), &offset
);
509 if (error
!= sizeof(ex
))
512 /* We come in here for the regular a.out style of shared libraries */
513 if ((N_MAGIC(ex
) != ZMAGIC
&& N_MAGIC(ex
) != QMAGIC
) || N_TRSIZE(ex
) ||
514 N_DRSIZE(ex
) || ((ex
.a_entry
& 0xfff) && N_MAGIC(ex
) == ZMAGIC
) ||
515 inode
->i_size
< ex
.a_text
+ex
.a_data
+N_SYMSIZE(ex
)+N_TXTOFF(ex
)) {
519 if (N_MAGIC(ex
) == ZMAGIC
&& N_TXTOFF(ex
) &&
520 (N_TXTOFF(ex
) < inode
->i_sb
->s_blocksize
)) {
521 printk("N_TXTOFF < BLOCK_SIZE. Please convert library\n");
528 /* For QMAGIC, the starting address is 0x20 into the page. We mask
529 this off to get the starting address for the page */
531 start_addr
= ex
.a_entry
& 0xfffff000;
533 /* Now use mmap to map the library into memory. */
534 error
= do_mmap(file
, start_addr
, ex
.a_text
+ ex
.a_data
,
535 PROT_READ
| PROT_WRITE
| PROT_EXEC
,
536 MAP_FIXED
| MAP_PRIVATE
| MAP_DENYWRITE
,
539 if (error
!= start_addr
)
542 len
= PAGE_ALIGN(ex
.a_text
+ ex
.a_data
);
543 bss
= ex
.a_text
+ ex
.a_data
+ ex
.a_bss
;
545 error
= do_mmap(NULL
, start_addr
+ len
, bss
- len
,
546 PROT_READ
| PROT_WRITE
| PROT_EXEC
,
547 MAP_PRIVATE
| MAP_FIXED
, 0);
549 if (error
!= start_addr
+ len
)
561 load_aout_library(int fd
)
566 retval
= do_load_aout_library(fd
);
572 int __init
init_aout_binfmt(void)
574 return register_binfmt(&aout_format
);
578 int init_module(void) {
579 return init_aout_binfmt();
582 void cleanup_module( void) {
583 unregister_binfmt(&aout_format
);