2 * linux/fs/binfmt_aout.c
4 * Copyright (C) 1991, 1992, 1996 Linus Torvalds
7 #include <linux/module.h>
9 #include <linux/time.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/slab.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/pgalloc.h>
31 #include <asm/cacheflush.h>
33 static int load_aout_binary(struct linux_binprm *, struct pt_regs * regs);
34 static int load_aout_library(struct file*);
35 static int aout_core_dump(long signr, struct pt_regs * regs, struct file *file);
37 extern void dump_thread(struct pt_regs *, struct user *);
39 static struct linux_binfmt aout_format = {
40 .module = THIS_MODULE,
41 .load_binary = load_aout_binary,
42 .load_shlib = load_aout_library,
43 .core_dump = aout_core_dump,
44 .min_coredump = PAGE_SIZE
47 static void set_brk(unsigned long start, unsigned long end)
49 start = PAGE_ALIGN(start);
50 end = PAGE_ALIGN(end);
53 do_brk(start, end - start);
57 * These are the only things you should do on a core-file: use only these
58 * macros to write out all the necessary info.
61 static int dump_write(struct file *file, const void *addr, int nr)
63 return file->f_op->write(file, addr, nr, &file->f_pos) == nr;
66 #define DUMP_WRITE(addr, nr) \
67 if (!dump_write(file, (void *)(addr), (nr))) \
70 #define DUMP_SEEK(offset) \
71 if (file->f_op->llseek) { \
72 if (file->f_op->llseek(file,(offset),0) != (offset)) \
74 } else file->f_pos = (offset)
77 * Routine writes a core dump image in the current directory.
78 * Currently only a stub-function.
80 * Note that setuid/setgid files won't make a core-dump if the uid/gid
81 * changed due to the set[u|g]id. It's enforced by the "current->mm->dumpable"
82 * field, which also makes sure the core-dumps won't be recursive if the
83 * dumping of the process results in another error..
86 static int aout_core_dump(long signr, struct pt_regs * regs, struct file *file)
90 unsigned long dump_start, dump_size;
92 #if defined(__alpha__)
93 # define START_DATA(u) (u.start_data)
94 #elif defined(__arm__)
95 # define START_DATA(u) ((u.u_tsize << PAGE_SHIFT) + u.start_code)
96 #elif defined(__sparc__)
97 # define START_DATA(u) (u.u_tsize)
98 #elif defined(__i386__) || defined(__mc68000__) || defined(__arch_um__)
99 # define START_DATA(u) (u.u_tsize << PAGE_SHIFT)
102 # define START_STACK(u) ((regs->u_regs[UREG_FP]) & ~(PAGE_SIZE - 1))
104 # define START_STACK(u) (u.start_stack)
110 current->flags |= PF_DUMPCORE;
111 strncpy(dump.u_comm, current->comm, sizeof(current->comm));
113 dump.u_ar0 = (void *)(((unsigned long)(&dump.regs)) - ((unsigned long)(&dump)));
116 dump_thread(regs, &dump);
118 /* If the size of the dump file exceeds the rlimit, then see what would happen
119 if we wrote the stack, but not the data area. */
121 if ((dump.u_dsize+dump.u_ssize) >
122 current->rlim[RLIMIT_CORE].rlim_cur)
125 if ((dump.u_dsize+dump.u_ssize+1) * PAGE_SIZE >
126 current->rlim[RLIMIT_CORE].rlim_cur)
130 /* Make sure we have enough room to write the stack and data areas. */
133 current->rlim[RLIMIT_CORE].rlim_cur)
136 if ((dump.u_ssize+1) * PAGE_SIZE >
137 current->rlim[RLIMIT_CORE].rlim_cur)
141 /* make sure we actually have a data and stack area to dump */
144 if (verify_area(VERIFY_READ, (void *) START_DATA(dump), dump.u_dsize))
146 if (verify_area(VERIFY_READ, (void *) START_STACK(dump), dump.u_ssize))
149 if (verify_area(VERIFY_READ, (void *) START_DATA(dump), dump.u_dsize << PAGE_SHIFT))
151 if (verify_area(VERIFY_READ, (void *) START_STACK(dump), dump.u_ssize << PAGE_SHIFT))
157 DUMP_WRITE(&dump,sizeof(dump));
158 /* Now dump all of the user data. Include malloced stuff as well */
160 DUMP_SEEK(PAGE_SIZE);
162 /* now we start writing out the user space info */
164 /* Dump the data area */
165 if (dump.u_dsize != 0) {
166 dump_start = START_DATA(dump);
168 dump_size = dump.u_dsize;
170 dump_size = dump.u_dsize << PAGE_SHIFT;
172 DUMP_WRITE(dump_start,dump_size);
174 /* Now prepare to dump the stack area */
175 if (dump.u_ssize != 0) {
176 dump_start = START_STACK(dump);
178 dump_size = dump.u_ssize;
180 dump_size = dump.u_ssize << PAGE_SHIFT;
182 DUMP_WRITE(dump_start,dump_size);
184 /* Finally dump the task struct. Not be used by gdb, but could be useful */
186 DUMP_WRITE(current,sizeof(*current));
193 * create_aout_tables() parses the env- and arg-strings in new user
194 * memory and creates the pointer tables from them, and puts their
195 * addresses on the "stack", returning the new stack pointer value.
197 static unsigned long * create_aout_tables(char * p, struct linux_binprm * bprm)
201 int argc = bprm->argc;
202 int envc = bprm->envc;
204 sp = (unsigned long *) ((-(unsigned long)sizeof(char *)) & (unsigned long) p);
206 /* This imposes the proper stack alignment for a new process. */
207 sp = (unsigned long *) (((unsigned long) sp) & ~7);
208 if ((envc+argc+3)&1) --sp;
211 /* whee.. test-programs are so much fun. */
216 put_user(0x3eb, --sp);
217 put_user(bprm->loader, --sp);
218 put_user(0x3ea, --sp);
220 put_user(bprm->exec, --sp);
221 put_user(0x3e9, --sp);
227 #if defined(__i386__) || defined(__mc68000__) || defined(__arm__) || defined(__arch_um__)
228 put_user((unsigned long) envp,--sp);
229 put_user((unsigned long) argv,--sp);
232 current->mm->arg_start = (unsigned long) p;
241 current->mm->arg_end = current->mm->env_start = (unsigned long) p;
250 current->mm->env_end = (unsigned long) p;
255 * These are the functions used to load a.out style executables and shared
256 * libraries. There is no binary dependent code anywhere else.
259 static int load_aout_binary(struct linux_binprm * bprm, struct pt_regs * regs)
263 unsigned long fd_offset;
267 ex = *((struct exec *) bprm->buf); /* exec-header */
268 if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != OMAGIC &&
269 N_MAGIC(ex) != QMAGIC && N_MAGIC(ex) != NMAGIC) ||
270 N_TRSIZE(ex) || N_DRSIZE(ex) ||
271 i_size_read(bprm->file->f_dentry->d_inode) < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
275 fd_offset = N_TXTOFF(ex);
277 /* Check initial limits. This avoids letting people circumvent
278 * size limits imposed on them by creating programs with large
279 * arrays in the data or bss.
281 rlim = current->rlim[RLIMIT_DATA].rlim_cur;
282 if (rlim >= RLIM_INFINITY)
284 if (ex.a_data + ex.a_bss > rlim)
287 /* Flush all traces of the currently running executable */
288 retval = flush_old_exec(bprm);
292 /* OK, This is the point of no return */
293 #if defined(__alpha__)
294 SET_AOUT_PERSONALITY(bprm, ex);
295 #elif defined(__sparc__)
296 set_personality(PER_SUNOS);
297 #if !defined(__sparc_v9__)
298 memcpy(¤t->thread.core_exec, &ex, sizeof(struct exec));
301 set_personality(PER_LINUX);
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) == NMAGIC) {
318 loff_t pos = fd_offset;
319 /* Fuck me plenty... */
321 error = do_brk(N_TXTADDR(ex), ex.a_text);
322 bprm->file->f_op->read(bprm->file, (char *) N_TXTADDR(ex),
324 error = do_brk(N_DATADDR(ex), ex.a_data);
325 bprm->file->f_op->read(bprm->file, (char *) N_DATADDR(ex),
331 if (N_MAGIC(ex) == OMAGIC) {
332 unsigned long text_addr, map_size;
335 text_addr = N_TXTADDR(ex);
337 #if defined(__alpha__) || defined(__sparc__)
339 map_size = ex.a_text+ex.a_data + PAGE_SIZE - 1;
342 map_size = ex.a_text+ex.a_data;
345 error = do_brk(text_addr & PAGE_MASK, map_size);
346 if (error != (text_addr & PAGE_MASK)) {
347 send_sig(SIGKILL, current, 0);
351 error = bprm->file->f_op->read(bprm->file, (char *)text_addr,
352 ex.a_text+ex.a_data, &pos);
353 if ((signed long)error < 0) {
354 send_sig(SIGKILL, current, 0);
358 flush_icache_range(text_addr, text_addr+ex.a_text+ex.a_data);
360 static unsigned long error_time, error_time2;
361 if ((ex.a_text & 0xfff || ex.a_data & 0xfff) &&
362 (N_MAGIC(ex) != NMAGIC) && (jiffies-error_time2) > 5*HZ)
364 printk(KERN_NOTICE "executable not page aligned\n");
365 error_time2 = jiffies;
368 if ((fd_offset & ~PAGE_MASK) != 0 &&
369 (jiffies-error_time) > 5*HZ)
372 "fd_offset is not page aligned. Please convert program: %s\n",
373 bprm->file->f_dentry->d_name.name);
374 error_time = jiffies;
377 if (!bprm->file->f_op->mmap||((fd_offset & ~PAGE_MASK) != 0)) {
378 loff_t pos = fd_offset;
379 do_brk(N_TXTADDR(ex), ex.a_text+ex.a_data);
380 bprm->file->f_op->read(bprm->file,(char *)N_TXTADDR(ex),
381 ex.a_text+ex.a_data, &pos);
382 flush_icache_range((unsigned long) N_TXTADDR(ex),
383 (unsigned long) N_TXTADDR(ex) +
384 ex.a_text+ex.a_data);
388 down_write(¤t->mm->mmap_sem);
389 error = do_mmap(bprm->file, N_TXTADDR(ex), ex.a_text,
390 PROT_READ | PROT_EXEC,
391 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE,
393 up_write(¤t->mm->mmap_sem);
395 if (error != N_TXTADDR(ex)) {
396 send_sig(SIGKILL, current, 0);
400 down_write(¤t->mm->mmap_sem);
401 error = do_mmap(bprm->file, N_DATADDR(ex), ex.a_data,
402 PROT_READ | PROT_WRITE | PROT_EXEC,
403 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE,
404 fd_offset + ex.a_text);
405 up_write(¤t->mm->mmap_sem);
406 if (error != N_DATADDR(ex)) {
407 send_sig(SIGKILL, current, 0);
412 set_binfmt(&aout_format);
414 set_brk(current->mm->start_brk, current->mm->brk);
416 retval = setup_arg_pages(bprm, EXSTACK_DEFAULT);
418 /* Someone check-me: is this error path enough? */
419 send_sig(SIGKILL, current, 0);
423 current->mm->start_stack =
424 (unsigned long) create_aout_tables((char *) bprm->p, bprm);
426 regs->gp = ex.a_gpvalue;
428 start_thread(regs, ex.a_entry, current->mm->start_stack);
429 if (unlikely(current->ptrace & PT_PTRACED)) {
430 if (current->ptrace & PT_TRACE_EXEC)
431 ptrace_notify ((PTRACE_EVENT_EXEC << 8) | SIGTRAP);
433 send_sig(SIGTRAP, current, 0);
438 static int load_aout_library(struct file *file)
440 struct inode * inode;
441 unsigned long bss, start_addr, len;
446 inode = file->f_dentry->d_inode;
449 error = kernel_read(file, 0, (char *) &ex, sizeof(ex));
450 if (error != sizeof(ex))
453 /* We come in here for the regular a.out style of shared libraries */
454 if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != QMAGIC) || N_TRSIZE(ex) ||
455 N_DRSIZE(ex) || ((ex.a_entry & 0xfff) && N_MAGIC(ex) == ZMAGIC) ||
456 i_size_read(inode) < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
463 /* For QMAGIC, the starting address is 0x20 into the page. We mask
464 this off to get the starting address for the page */
466 start_addr = ex.a_entry & 0xfffff000;
468 if ((N_TXTOFF(ex) & ~PAGE_MASK) != 0) {
469 static unsigned long error_time;
470 loff_t pos = N_TXTOFF(ex);
472 if ((jiffies-error_time) > 5*HZ)
475 "N_TXTOFF is not page aligned. Please convert library: %s\n",
476 file->f_dentry->d_name.name);
477 error_time = jiffies;
480 do_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);
482 file->f_op->read(file, (char *)start_addr,
483 ex.a_text + ex.a_data, &pos);
484 flush_icache_range((unsigned long) start_addr,
485 (unsigned long) start_addr + ex.a_text + ex.a_data);
490 /* Now use mmap to map the library into memory. */
491 down_write(¤t->mm->mmap_sem);
492 error = do_mmap(file, start_addr, ex.a_text + ex.a_data,
493 PROT_READ | PROT_WRITE | PROT_EXEC,
494 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE,
496 up_write(¤t->mm->mmap_sem);
498 if (error != start_addr)
501 len = PAGE_ALIGN(ex.a_text + ex.a_data);
502 bss = ex.a_text + ex.a_data + ex.a_bss;
504 error = do_brk(start_addr + len, bss - len);
506 if (error != start_addr + len)
514 static int __init init_aout_binfmt(void)
516 return register_binfmt(&aout_format);
519 static void __exit exit_aout_binfmt(void)
521 unregister_binfmt(&aout_format);
524 module_init(init_aout_binfmt);
525 module_exit(exit_aout_binfmt);
526 MODULE_LICENSE("GPL");