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
);
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
)
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
) >
109 current
->signal
->rlim
[RLIMIT_CORE
].rlim_cur
)
112 /* Make sure we have enough room to write the stack and data areas. */
114 current
->signal
->rlim
[RLIMIT_CORE
].rlim_cur
)
117 /* make sure we actually have a data and stack area to dump */
119 if (!access_ok(VERIFY_READ
, (void __user
*) START_DATA(dump
), dump
.u_dsize
))
121 if (!access_ok(VERIFY_READ
, (void __user
*) START_STACK(dump
), dump
.u_ssize
))
126 DUMP_WRITE(&dump
,sizeof(dump
));
127 /* now we start writing out the user space info */
129 /* Dump the data area */
130 if (dump
.u_dsize
!= 0) {
131 dump_start
= START_DATA(dump
);
132 dump_size
= dump
.u_dsize
;
133 DUMP_WRITE(dump_start
,dump_size
);
135 /* Now prepare to dump the stack area */
136 if (dump
.u_ssize
!= 0) {
137 dump_start
= START_STACK(dump
);
138 dump_size
= dump
.u_ssize
;
139 DUMP_WRITE(dump_start
,dump_size
);
141 /* Finally dump the task struct. Not be used by gdb, but could be useful */
143 DUMP_WRITE(current
,sizeof(*current
));
150 * create_aout32_tables() parses the env- and arg-strings in new user
151 * memory and creates the pointer tables from them, and puts their
152 * addresses on the "stack", returning the new stack pointer value.
155 static u32 __user
*create_aout32_tables(char __user
*p
, struct linux_binprm
*bprm
)
160 int argc
= bprm
->argc
;
161 int envc
= bprm
->envc
;
163 sp
= (u32 __user
*)((-(unsigned long)sizeof(char *))&(unsigned long)p
);
165 /* This imposes the proper stack alignment for a new process. */
166 sp
= (u32 __user
*) (((unsigned long) sp
) & ~7);
175 current
->mm
->arg_start
= (unsigned long) p
;
178 put_user(((u32
)(unsigned long)(p
)),argv
++);
184 current
->mm
->arg_end
= current
->mm
->env_start
= (unsigned long) p
;
187 put_user(((u32
)(unsigned long)(p
)),envp
++);
193 current
->mm
->env_end
= (unsigned long) p
;
198 * These are the functions used to load a.out style executables and shared
199 * libraries. There is no binary dependent code anywhere else.
202 static int load_aout32_binary(struct linux_binprm
* bprm
, struct pt_regs
* regs
)
206 unsigned long fd_offset
;
208 unsigned long orig_thr_flags
;
211 ex
= *((struct exec
*) bprm
->buf
); /* exec-header */
212 if ((N_MAGIC(ex
) != ZMAGIC
&& N_MAGIC(ex
) != OMAGIC
&&
213 N_MAGIC(ex
) != QMAGIC
&& N_MAGIC(ex
) != NMAGIC
) ||
214 N_TRSIZE(ex
) || N_DRSIZE(ex
) ||
215 bprm
->file
->f_path
.dentry
->d_inode
->i_size
< ex
.a_text
+ex
.a_data
+N_SYMSIZE(ex
)+N_TXTOFF(ex
)) {
219 fd_offset
= N_TXTOFF(ex
);
221 /* Check initial limits. This avoids letting people circumvent
222 * size limits imposed on them by creating programs with large
223 * arrays in the data or bss.
225 rlim
= current
->signal
->rlim
[RLIMIT_DATA
].rlim_cur
;
226 if (rlim
>= RLIM_INFINITY
)
228 if (ex
.a_data
+ ex
.a_bss
> rlim
)
231 /* Flush all traces of the currently running executable */
232 retval
= flush_old_exec(bprm
);
236 /* OK, This is the point of no return */
237 set_personality(PER_SUNOS
);
239 current
->mm
->end_code
= ex
.a_text
+
240 (current
->mm
->start_code
= N_TXTADDR(ex
));
241 current
->mm
->end_data
= ex
.a_data
+
242 (current
->mm
->start_data
= N_DATADDR(ex
));
243 current
->mm
->brk
= ex
.a_bss
+
244 (current
->mm
->start_brk
= N_BSSADDR(ex
));
245 current
->mm
->free_area_cache
= current
->mm
->mmap_base
;
246 current
->mm
->cached_hole_size
= 0;
248 current
->mm
->mmap
= NULL
;
250 current
->flags
&= ~PF_FORKNOEXEC
;
251 if (N_MAGIC(ex
) == NMAGIC
) {
252 loff_t pos
= fd_offset
;
253 /* Fuck me plenty... */
254 down_write(¤t
->mm
->mmap_sem
);
255 error
= do_brk(N_TXTADDR(ex
), ex
.a_text
);
256 up_write(¤t
->mm
->mmap_sem
);
257 bprm
->file
->f_op
->read(bprm
->file
, (char __user
*)N_TXTADDR(ex
),
259 down_write(¤t
->mm
->mmap_sem
);
260 error
= do_brk(N_DATADDR(ex
), ex
.a_data
);
261 up_write(¤t
->mm
->mmap_sem
);
262 bprm
->file
->f_op
->read(bprm
->file
, (char __user
*)N_DATADDR(ex
),
267 if (N_MAGIC(ex
) == OMAGIC
) {
268 loff_t pos
= fd_offset
;
269 down_write(¤t
->mm
->mmap_sem
);
270 do_brk(N_TXTADDR(ex
) & PAGE_MASK
,
271 ex
.a_text
+ex
.a_data
+ PAGE_SIZE
- 1);
272 up_write(¤t
->mm
->mmap_sem
);
273 bprm
->file
->f_op
->read(bprm
->file
, (char __user
*)N_TXTADDR(ex
),
274 ex
.a_text
+ex
.a_data
, &pos
);
276 static unsigned long error_time
;
277 if ((ex
.a_text
& 0xfff || ex
.a_data
& 0xfff) &&
278 (N_MAGIC(ex
) != NMAGIC
) && (jiffies
-error_time
) > 5*HZ
)
280 printk(KERN_NOTICE
"executable not page aligned\n");
281 error_time
= jiffies
;
284 if (!bprm
->file
->f_op
->mmap
) {
285 loff_t pos
= fd_offset
;
286 down_write(¤t
->mm
->mmap_sem
);
287 do_brk(0, ex
.a_text
+ex
.a_data
);
288 up_write(¤t
->mm
->mmap_sem
);
289 bprm
->file
->f_op
->read(bprm
->file
,
290 (char __user
*)N_TXTADDR(ex
),
291 ex
.a_text
+ex
.a_data
, &pos
);
295 down_write(¤t
->mm
->mmap_sem
);
296 error
= do_mmap(bprm
->file
, N_TXTADDR(ex
), ex
.a_text
,
297 PROT_READ
| PROT_EXEC
,
298 MAP_FIXED
| MAP_PRIVATE
| MAP_DENYWRITE
| MAP_EXECUTABLE
,
300 up_write(¤t
->mm
->mmap_sem
);
302 if (error
!= N_TXTADDR(ex
)) {
303 send_sig(SIGKILL
, current
, 0);
307 down_write(¤t
->mm
->mmap_sem
);
308 error
= do_mmap(bprm
->file
, N_DATADDR(ex
), ex
.a_data
,
309 PROT_READ
| PROT_WRITE
| PROT_EXEC
,
310 MAP_FIXED
| MAP_PRIVATE
| MAP_DENYWRITE
| MAP_EXECUTABLE
,
311 fd_offset
+ ex
.a_text
);
312 up_write(¤t
->mm
->mmap_sem
);
313 if (error
!= N_DATADDR(ex
)) {
314 send_sig(SIGKILL
, current
, 0);
319 set_binfmt(&aout32_format
);
321 set_brk(current
->mm
->start_brk
, current
->mm
->brk
);
323 /* Make sure STACK_TOP returns the right thing. */
324 orig_thr_flags
= current_thread_info()->flags
;
325 current_thread_info()->flags
|= _TIF_32BIT
;
327 retval
= setup_arg_pages(bprm
, STACK_TOP
, EXSTACK_DEFAULT
);
329 current_thread_info()->flags
= orig_thr_flags
;
331 /* Someone check-me: is this error path enough? */
332 send_sig(SIGKILL
, current
, 0);
336 current
->mm
->start_stack
=
337 (unsigned long) create_aout32_tables((char __user
*)bprm
->p
, bprm
);
338 tsb_context_switch(current
->mm
);
340 start_thread32(regs
, ex
.a_entry
, current
->mm
->start_stack
);
341 if (current
->ptrace
& PT_PTRACED
)
342 send_sig(SIGTRAP
, current
, 0);
346 /* N.B. Move to .h file and use code in fs/binfmt_aout.c? */
347 static int load_aout32_library(struct file
*file
)
349 struct inode
* inode
;
350 unsigned long bss
, start_addr
, len
;
355 inode
= file
->f_path
.dentry
->d_inode
;
358 error
= kernel_read(file
, 0, (char *) &ex
, sizeof(ex
));
359 if (error
!= sizeof(ex
))
362 /* We come in here for the regular a.out style of shared libraries */
363 if ((N_MAGIC(ex
) != ZMAGIC
&& N_MAGIC(ex
) != QMAGIC
) || N_TRSIZE(ex
) ||
364 N_DRSIZE(ex
) || ((ex
.a_entry
& 0xfff) && N_MAGIC(ex
) == ZMAGIC
) ||
365 inode
->i_size
< ex
.a_text
+ex
.a_data
+N_SYMSIZE(ex
)+N_TXTOFF(ex
)) {
369 if (N_MAGIC(ex
) == ZMAGIC
&& N_TXTOFF(ex
) &&
370 (N_TXTOFF(ex
) < inode
->i_sb
->s_blocksize
)) {
371 printk("N_TXTOFF < BLOCK_SIZE. Please convert library\n");
378 /* For QMAGIC, the starting address is 0x20 into the page. We mask
379 this off to get the starting address for the page */
381 start_addr
= ex
.a_entry
& 0xfffff000;
383 /* Now use mmap to map the library into memory. */
384 down_write(¤t
->mm
->mmap_sem
);
385 error
= do_mmap(file
, start_addr
, ex
.a_text
+ ex
.a_data
,
386 PROT_READ
| PROT_WRITE
| PROT_EXEC
,
387 MAP_FIXED
| MAP_PRIVATE
| MAP_DENYWRITE
,
389 up_write(¤t
->mm
->mmap_sem
);
391 if (error
!= start_addr
)
394 len
= PAGE_ALIGN(ex
.a_text
+ ex
.a_data
);
395 bss
= ex
.a_text
+ ex
.a_data
+ ex
.a_bss
;
397 down_write(¤t
->mm
->mmap_sem
);
398 error
= do_brk(start_addr
+ len
, bss
- len
);
399 up_write(¤t
->mm
->mmap_sem
);
401 if (error
!= start_addr
+ len
)
409 static int __init
init_aout32_binfmt(void)
411 return register_binfmt(&aout32_format
);
414 static void __exit
exit_aout32_binfmt(void)
416 unregister_binfmt(&aout32_format
);
419 module_init(init_aout32_binfmt
);
420 module_exit(exit_aout32_binfmt
);