2 * linux/fs/binfmt_aout.c
4 * Copyright (C) 1991, 1992, 1996 Linus Torvalds
6 * Hacked a bit by DaveM to make it work with 32-bit SunOS
7 * binaries on the sparc64 port.
10 #include <linux/module.h>
12 #include <linux/sched.h>
13 #include <linux/kernel.h>
15 #include <linux/mman.h>
16 #include <linux/a.out.h>
17 #include <linux/errno.h>
18 #include <linux/signal.h>
19 #include <linux/string.h>
21 #include <linux/file.h>
22 #include <linux/stat.h>
23 #include <linux/fcntl.h>
24 #include <linux/ptrace.h>
25 #include <linux/user.h>
26 #include <linux/slab.h>
27 #include <linux/binfmts.h>
28 #include <linux/personality.h>
29 #include <linux/init.h>
31 #include <asm/system.h>
32 #include <asm/uaccess.h>
33 #include <asm/pgalloc.h>
34 #include <asm/mmu_context.h>
36 static int load_aout32_binary(struct linux_binprm
*, struct pt_regs
* regs
);
37 static int load_aout32_library(struct file
*);
38 static int aout32_core_dump(long signr
, struct pt_regs
*regs
, struct file
*file
, unsigned long limit
);
40 static struct linux_binfmt aout32_format
= {
41 .module
= THIS_MODULE
,
42 .load_binary
= load_aout32_binary
,
43 .load_shlib
= load_aout32_library
,
44 .core_dump
= aout32_core_dump
,
45 .min_coredump
= PAGE_SIZE
,
48 static void set_brk(unsigned long start
, unsigned long end
)
50 start
= PAGE_ALIGN(start
);
51 end
= PAGE_ALIGN(end
);
54 down_write(¤t
->mm
->mmap_sem
);
55 do_brk(start
, end
- start
);
56 up_write(¤t
->mm
->mmap_sem
);
60 * These are the only things you should do on a core-file: use only these
61 * macros to write out all the necessary info.
64 static int dump_write(struct file
*file
, const void *addr
, int nr
)
66 return file
->f_op
->write(file
, addr
, nr
, &file
->f_pos
) == nr
;
69 #define DUMP_WRITE(addr, nr) \
70 if (!dump_write(file, (void *)(addr), (nr))) \
73 #define DUMP_SEEK(offset) \
74 if (file->f_op->llseek) { \
75 if (file->f_op->llseek(file,(offset),0) != (offset)) \
77 } else file->f_pos = (offset)
80 * Routine writes a core dump image in the current directory.
81 * Currently only a stub-function.
83 * Note that setuid/setgid files won't make a core-dump if the uid/gid
84 * changed due to the set[u|g]id. It's enforced by the "current->mm->dumpable"
85 * field, which also makes sure the core-dumps won't be recursive if the
86 * dumping of the process results in another error..
89 static int aout32_core_dump(long signr
, struct pt_regs
*regs
, struct file
*file
, unsigned long limit
)
93 unsigned long dump_start
, dump_size
;
95 # define START_DATA(u) (u.u_tsize)
96 # define START_STACK(u) ((regs->u_regs[UREG_FP]) & ~(PAGE_SIZE - 1))
101 current
->flags
|= PF_DUMPCORE
;
102 strncpy(dump
.u_comm
, current
->comm
, sizeof(dump
.u_comm
));
104 dump_thread(regs
, &dump
);
106 /* If the size of the dump file exceeds the rlimit, then see what would happen
107 if we wrote the stack, but not the data area. */
108 if (dump
.u_dsize
+ dump
.u_ssize
> limit
)
111 /* Make sure we have enough room to write the stack and data areas. */
112 if (dump
.u_ssize
> limit
)
115 /* make sure we actually have a data and stack area to dump */
117 if (!access_ok(VERIFY_READ
, (void __user
*) START_DATA(dump
), dump
.u_dsize
))
119 if (!access_ok(VERIFY_READ
, (void __user
*) START_STACK(dump
), dump
.u_ssize
))
124 DUMP_WRITE(&dump
,sizeof(dump
));
125 /* now we start writing out the user space info */
127 /* Dump the data area */
128 if (dump
.u_dsize
!= 0) {
129 dump_start
= START_DATA(dump
);
130 dump_size
= dump
.u_dsize
;
131 DUMP_WRITE(dump_start
,dump_size
);
133 /* Now prepare to dump the stack area */
134 if (dump
.u_ssize
!= 0) {
135 dump_start
= START_STACK(dump
);
136 dump_size
= dump
.u_ssize
;
137 DUMP_WRITE(dump_start
,dump_size
);
139 /* Finally dump the task struct. Not be used by gdb, but could be useful */
141 DUMP_WRITE(current
,sizeof(*current
));
148 * create_aout32_tables() parses the env- and arg-strings in new user
149 * memory and creates the pointer tables from them, and puts their
150 * addresses on the "stack", returning the new stack pointer value.
153 static u32 __user
*create_aout32_tables(char __user
*p
, struct linux_binprm
*bprm
)
158 int argc
= bprm
->argc
;
159 int envc
= bprm
->envc
;
161 sp
= (u32 __user
*)((-(unsigned long)sizeof(char *))&(unsigned long)p
);
163 /* This imposes the proper stack alignment for a new process. */
164 sp
= (u32 __user
*) (((unsigned long) sp
) & ~7);
173 current
->mm
->arg_start
= (unsigned long) p
;
176 put_user(((u32
)(unsigned long)(p
)),argv
++);
182 current
->mm
->arg_end
= current
->mm
->env_start
= (unsigned long) p
;
185 put_user(((u32
)(unsigned long)(p
)),envp
++);
191 current
->mm
->env_end
= (unsigned long) p
;
196 * These are the functions used to load a.out style executables and shared
197 * libraries. There is no binary dependent code anywhere else.
200 static int load_aout32_binary(struct linux_binprm
* bprm
, struct pt_regs
* regs
)
204 unsigned long fd_offset
;
206 unsigned long orig_thr_flags
;
209 ex
= *((struct exec
*) bprm
->buf
); /* exec-header */
210 if ((N_MAGIC(ex
) != ZMAGIC
&& N_MAGIC(ex
) != OMAGIC
&&
211 N_MAGIC(ex
) != QMAGIC
&& N_MAGIC(ex
) != NMAGIC
) ||
212 N_TRSIZE(ex
) || N_DRSIZE(ex
) ||
213 bprm
->file
->f_path
.dentry
->d_inode
->i_size
< ex
.a_text
+ex
.a_data
+N_SYMSIZE(ex
)+N_TXTOFF(ex
)) {
217 fd_offset
= N_TXTOFF(ex
);
219 /* Check initial limits. This avoids letting people circumvent
220 * size limits imposed on them by creating programs with large
221 * arrays in the data or bss.
223 rlim
= current
->signal
->rlim
[RLIMIT_DATA
].rlim_cur
;
224 if (rlim
>= RLIM_INFINITY
)
226 if (ex
.a_data
+ ex
.a_bss
> rlim
)
229 /* Flush all traces of the currently running executable */
230 retval
= flush_old_exec(bprm
);
234 /* OK, This is the point of no return */
235 set_personality(PER_SUNOS
);
237 current
->mm
->end_code
= ex
.a_text
+
238 (current
->mm
->start_code
= N_TXTADDR(ex
));
239 current
->mm
->end_data
= ex
.a_data
+
240 (current
->mm
->start_data
= N_DATADDR(ex
));
241 current
->mm
->brk
= ex
.a_bss
+
242 (current
->mm
->start_brk
= N_BSSADDR(ex
));
243 current
->mm
->free_area_cache
= current
->mm
->mmap_base
;
244 current
->mm
->cached_hole_size
= 0;
246 current
->mm
->mmap
= NULL
;
248 current
->flags
&= ~PF_FORKNOEXEC
;
249 if (N_MAGIC(ex
) == NMAGIC
) {
250 loff_t pos
= fd_offset
;
251 /* Fuck me plenty... */
252 down_write(¤t
->mm
->mmap_sem
);
253 error
= do_brk(N_TXTADDR(ex
), ex
.a_text
);
254 up_write(¤t
->mm
->mmap_sem
);
255 bprm
->file
->f_op
->read(bprm
->file
, (char __user
*)N_TXTADDR(ex
),
257 down_write(¤t
->mm
->mmap_sem
);
258 error
= do_brk(N_DATADDR(ex
), ex
.a_data
);
259 up_write(¤t
->mm
->mmap_sem
);
260 bprm
->file
->f_op
->read(bprm
->file
, (char __user
*)N_DATADDR(ex
),
265 if (N_MAGIC(ex
) == OMAGIC
) {
266 loff_t pos
= fd_offset
;
267 down_write(¤t
->mm
->mmap_sem
);
268 do_brk(N_TXTADDR(ex
) & PAGE_MASK
,
269 ex
.a_text
+ex
.a_data
+ PAGE_SIZE
- 1);
270 up_write(¤t
->mm
->mmap_sem
);
271 bprm
->file
->f_op
->read(bprm
->file
, (char __user
*)N_TXTADDR(ex
),
272 ex
.a_text
+ex
.a_data
, &pos
);
274 static unsigned long error_time
;
275 if ((ex
.a_text
& 0xfff || ex
.a_data
& 0xfff) &&
276 (N_MAGIC(ex
) != NMAGIC
) && (jiffies
-error_time
) > 5*HZ
)
278 printk(KERN_NOTICE
"executable not page aligned\n");
279 error_time
= jiffies
;
282 if (!bprm
->file
->f_op
->mmap
) {
283 loff_t pos
= fd_offset
;
284 down_write(¤t
->mm
->mmap_sem
);
285 do_brk(0, ex
.a_text
+ex
.a_data
);
286 up_write(¤t
->mm
->mmap_sem
);
287 bprm
->file
->f_op
->read(bprm
->file
,
288 (char __user
*)N_TXTADDR(ex
),
289 ex
.a_text
+ex
.a_data
, &pos
);
293 down_write(¤t
->mm
->mmap_sem
);
294 error
= do_mmap(bprm
->file
, N_TXTADDR(ex
), ex
.a_text
,
295 PROT_READ
| PROT_EXEC
,
296 MAP_FIXED
| MAP_PRIVATE
| MAP_DENYWRITE
| MAP_EXECUTABLE
,
298 up_write(¤t
->mm
->mmap_sem
);
300 if (error
!= N_TXTADDR(ex
)) {
301 send_sig(SIGKILL
, current
, 0);
305 down_write(¤t
->mm
->mmap_sem
);
306 error
= do_mmap(bprm
->file
, N_DATADDR(ex
), ex
.a_data
,
307 PROT_READ
| PROT_WRITE
| PROT_EXEC
,
308 MAP_FIXED
| MAP_PRIVATE
| MAP_DENYWRITE
| MAP_EXECUTABLE
,
309 fd_offset
+ ex
.a_text
);
310 up_write(¤t
->mm
->mmap_sem
);
311 if (error
!= N_DATADDR(ex
)) {
312 send_sig(SIGKILL
, current
, 0);
317 set_binfmt(&aout32_format
);
319 set_brk(current
->mm
->start_brk
, current
->mm
->brk
);
321 /* Make sure STACK_TOP returns the right thing. */
322 orig_thr_flags
= current_thread_info()->flags
;
323 current_thread_info()->flags
|= _TIF_32BIT
;
325 retval
= setup_arg_pages(bprm
, STACK_TOP
, EXSTACK_DEFAULT
);
327 current_thread_info()->flags
= orig_thr_flags
;
329 /* Someone check-me: is this error path enough? */
330 send_sig(SIGKILL
, current
, 0);
334 current
->mm
->start_stack
=
335 (unsigned long) create_aout32_tables((char __user
*)bprm
->p
, bprm
);
336 tsb_context_switch(current
->mm
);
338 start_thread32(regs
, ex
.a_entry
, current
->mm
->start_stack
);
339 if (current
->ptrace
& PT_PTRACED
)
340 send_sig(SIGTRAP
, current
, 0);
344 /* N.B. Move to .h file and use code in fs/binfmt_aout.c? */
345 static int load_aout32_library(struct file
*file
)
347 struct inode
* inode
;
348 unsigned long bss
, start_addr
, len
;
353 inode
= file
->f_path
.dentry
->d_inode
;
356 error
= kernel_read(file
, 0, (char *) &ex
, sizeof(ex
));
357 if (error
!= sizeof(ex
))
360 /* We come in here for the regular a.out style of shared libraries */
361 if ((N_MAGIC(ex
) != ZMAGIC
&& N_MAGIC(ex
) != QMAGIC
) || N_TRSIZE(ex
) ||
362 N_DRSIZE(ex
) || ((ex
.a_entry
& 0xfff) && N_MAGIC(ex
) == ZMAGIC
) ||
363 inode
->i_size
< ex
.a_text
+ex
.a_data
+N_SYMSIZE(ex
)+N_TXTOFF(ex
)) {
367 if (N_MAGIC(ex
) == ZMAGIC
&& N_TXTOFF(ex
) &&
368 (N_TXTOFF(ex
) < inode
->i_sb
->s_blocksize
)) {
369 printk("N_TXTOFF < BLOCK_SIZE. Please convert library\n");
376 /* For QMAGIC, the starting address is 0x20 into the page. We mask
377 this off to get the starting address for the page */
379 start_addr
= ex
.a_entry
& 0xfffff000;
381 /* Now use mmap to map the library into memory. */
382 down_write(¤t
->mm
->mmap_sem
);
383 error
= do_mmap(file
, start_addr
, ex
.a_text
+ ex
.a_data
,
384 PROT_READ
| PROT_WRITE
| PROT_EXEC
,
385 MAP_FIXED
| MAP_PRIVATE
| MAP_DENYWRITE
,
387 up_write(¤t
->mm
->mmap_sem
);
389 if (error
!= start_addr
)
392 len
= PAGE_ALIGN(ex
.a_text
+ ex
.a_data
);
393 bss
= ex
.a_text
+ ex
.a_data
+ ex
.a_bss
;
395 down_write(¤t
->mm
->mmap_sem
);
396 error
= do_brk(start_addr
+ len
, bss
- len
);
397 up_write(¤t
->mm
->mmap_sem
);
399 if (error
!= start_addr
+ len
)
407 static int __init
init_aout32_binfmt(void)
409 return register_binfmt(&aout32_format
);
412 static void __exit
exit_aout32_binfmt(void)
414 unregister_binfmt(&aout32_format
);
417 module_init(init_aout32_binfmt
);
418 module_exit(exit_aout32_binfmt
);