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/binfmts.h>
25 #include <linux/personality.h>
26 #include <linux/init.h>
27 #include <linux/jiffies.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>
37 #undef CORE_DUMP /* probably broken */
39 static int load_aout_binary(struct linux_binprm *, struct pt_regs *regs);
40 static int load_aout_library(struct file *);
43 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->sp & ~(PAGE_SIZE - 1);
57 dump->u_tsize = ((unsigned long) current->mm->end_code) >> PAGE_SHIFT;
58 dump->u_dsize = ((unsigned long)
59 (current->mm->brk + (PAGE_SIZE-1))) >> PAGE_SHIFT;
60 dump->u_dsize -= dump->u_tsize;
62 dump->u_debugreg[0] = current->thread.debugreg0;
63 dump->u_debugreg[1] = current->thread.debugreg1;
64 dump->u_debugreg[2] = current->thread.debugreg2;
65 dump->u_debugreg[3] = current->thread.debugreg3;
66 dump->u_debugreg[4] = 0;
67 dump->u_debugreg[5] = 0;
68 dump->u_debugreg[6] = current->thread.debugreg6;
69 dump->u_debugreg[7] = current->thread.debugreg7;
71 if (dump->start_stack < 0xc0000000) {
74 tmp = (unsigned long) (0xc0000000 - dump->start_stack);
75 dump->u_ssize = tmp >> PAGE_SHIFT;
78 dump->regs.bx = regs->bx;
79 dump->regs.cx = regs->cx;
80 dump->regs.dx = regs->dx;
81 dump->regs.si = regs->si;
82 dump->regs.di = regs->di;
83 dump->regs.bp = regs->bp;
84 dump->regs.ax = regs->ax;
85 dump->regs.ds = current->thread.ds;
86 dump->regs.es = current->thread.es;
91 dump->regs.orig_ax = regs->orig_ax;
92 dump->regs.ip = regs->ip;
93 dump->regs.cs = regs->cs;
94 dump->regs.flags = regs->flags;
95 dump->regs.sp = regs->sp;
96 dump->regs.ss = regs->ss;
101 dump->u_fpvalid = dump_fpu(regs, &dump->i387);
107 static struct linux_binfmt aout_format = {
108 .module = THIS_MODULE,
109 .load_binary = load_aout_binary,
110 .load_shlib = load_aout_library,
112 .core_dump = aout_core_dump,
114 .min_coredump = PAGE_SIZE
117 static void set_brk(unsigned long start, unsigned long end)
119 start = PAGE_ALIGN(start);
120 end = PAGE_ALIGN(end);
123 down_write(¤t->mm->mmap_sem);
124 do_brk(start, end - start);
125 up_write(¤t->mm->mmap_sem);
130 * These are the only things you should do on a core-file: use only these
131 * macros to write out all the necessary info.
134 static int dump_write(struct file *file, const void *addr, int nr)
136 return file->f_op->write(file, addr, nr, &file->f_pos) == nr;
139 #define DUMP_WRITE(addr, nr) \
140 if (!dump_write(file, (void *)(addr), (nr))) \
143 #define DUMP_SEEK(offset) \
144 if (file->f_op->llseek) { \
145 if (file->f_op->llseek(file, (offset), 0) != (offset)) \
148 file->f_pos = (offset)
150 #define START_DATA() (u.u_tsize << PAGE_SHIFT)
151 #define START_STACK(u) (u.start_stack)
154 * Routine writes a core dump image in the current directory.
155 * Currently only a stub-function.
157 * Note that setuid/setgid files won't make a core-dump if the uid/gid
158 * changed due to the set[u|g]id. It's enforced by the "current->mm->dumpable"
159 * field, which also makes sure the core-dumps won't be recursive if the
160 * dumping of the process results in another error..
163 static int aout_core_dump(long signr, struct pt_regs *regs, struct file *file,
168 unsigned long dump_start, dump_size;
174 current->flags |= PF_DUMPCORE;
175 strncpy(dump.u_comm, current->comm, sizeof(current->comm));
176 dump.u_ar0 = offsetof(struct user32, regs);
178 dump_thread32(regs, &dump);
181 * If the size of the dump file exceeds the rlimit, then see
182 * what would happen if we wrote the stack, but not the data
185 if ((dump.u_dsize + dump.u_ssize + 1) * PAGE_SIZE > limit)
188 /* Make sure we have enough room to write the stack and data areas. */
189 if ((dump.u_ssize + 1) * PAGE_SIZE > limit)
192 /* make sure we actually have a data and stack area to dump */
194 if (!access_ok(VERIFY_READ, (void *) (unsigned long)START_DATA(dump),
195 dump.u_dsize << PAGE_SHIFT))
197 if (!access_ok(VERIFY_READ, (void *) (unsigned long)START_STACK(dump),
198 dump.u_ssize << PAGE_SHIFT))
203 DUMP_WRITE(&dump, sizeof(dump));
204 /* Now dump all of the user data. Include malloced stuff as well */
205 DUMP_SEEK(PAGE_SIZE);
206 /* now we start writing out the user space info */
208 /* Dump the data area */
209 if (dump.u_dsize != 0) {
210 dump_start = START_DATA(dump);
211 dump_size = dump.u_dsize << PAGE_SHIFT;
212 DUMP_WRITE(dump_start, dump_size);
214 /* Now prepare to dump the stack area */
215 if (dump.u_ssize != 0) {
216 dump_start = START_STACK(dump);
217 dump_size = dump.u_ssize << PAGE_SHIFT;
218 DUMP_WRITE(dump_start, dump_size);
221 * Finally dump the task struct. Not be used by gdb, but
225 DUMP_WRITE(current, sizeof(*current));
233 * create_aout_tables() parses the env- and arg-strings in new user
234 * memory and creates the pointer tables from them, and puts their
235 * addresses on the "stack", returning the new stack pointer value.
237 static u32 __user *create_aout_tables(char __user *p, struct linux_binprm *bprm)
239 u32 __user *argv, *envp, *sp;
240 int argc = bprm->argc, envc = bprm->envc;
242 sp = (u32 __user *) ((-(unsigned long)sizeof(u32)) & (unsigned long) p);
247 put_user((unsigned long) envp, --sp);
248 put_user((unsigned long) argv, --sp);
249 put_user(argc, --sp);
250 current->mm->arg_start = (unsigned long) p;
254 put_user((u32)(unsigned long)p, argv++);
260 current->mm->arg_end = current->mm->env_start = (unsigned long) p;
264 put_user((u32)(unsigned long)p, envp++);
270 current->mm->env_end = (unsigned long) p;
275 * These are the functions used to load a.out style executables and shared
276 * libraries. There is no binary dependent code anywhere else.
278 static int load_aout_binary(struct linux_binprm *bprm, struct pt_regs *regs)
280 unsigned long error, fd_offset, rlim;
284 ex = *((struct exec *) bprm->buf); /* exec-header */
285 if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != OMAGIC &&
286 N_MAGIC(ex) != QMAGIC && N_MAGIC(ex) != NMAGIC) ||
287 N_TRSIZE(ex) || N_DRSIZE(ex) ||
288 i_size_read(bprm->file->f_path.dentry->d_inode) <
289 ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
293 fd_offset = N_TXTOFF(ex);
295 /* Check initial limits. This avoids letting people circumvent
296 * size limits imposed on them by creating programs with large
297 * arrays in the data or bss.
299 rlim = rlimit(RLIMIT_DATA);
300 if (rlim >= RLIM_INFINITY)
302 if (ex.a_data + ex.a_bss > rlim)
305 /* Flush all traces of the currently running executable */
306 retval = flush_old_exec(bprm);
310 /* OK, This is the point of no return */
311 set_personality(PER_LINUX);
312 set_thread_flag(TIF_IA32);
314 setup_new_exec(bprm);
316 regs->cs = __USER32_CS;
317 regs->r8 = regs->r9 = regs->r10 = regs->r11 = regs->r12 =
318 regs->r13 = regs->r14 = regs->r15 = 0;
320 current->mm->end_code = ex.a_text +
321 (current->mm->start_code = N_TXTADDR(ex));
322 current->mm->end_data = ex.a_data +
323 (current->mm->start_data = N_DATADDR(ex));
324 current->mm->brk = ex.a_bss +
325 (current->mm->start_brk = N_BSSADDR(ex));
326 current->mm->free_area_cache = TASK_UNMAPPED_BASE;
327 current->mm->cached_hole_size = 0;
329 install_exec_creds(bprm);
330 current->flags &= ~PF_FORKNOEXEC;
332 if (N_MAGIC(ex) == OMAGIC) {
333 unsigned long text_addr, map_size;
336 text_addr = N_TXTADDR(ex);
339 map_size = ex.a_text+ex.a_data;
341 down_write(¤t->mm->mmap_sem);
342 error = do_brk(text_addr & PAGE_MASK, map_size);
343 up_write(¤t->mm->mmap_sem);
345 if (error != (text_addr & PAGE_MASK)) {
346 send_sig(SIGKILL, current, 0);
350 error = bprm->file->f_op->read(bprm->file,
351 (char __user *)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);
361 static unsigned long error_time, error_time2;
362 if ((ex.a_text & 0xfff || ex.a_data & 0xfff) &&
363 (N_MAGIC(ex) != NMAGIC) &&
364 time_after(jiffies, error_time2 + 5*HZ)) {
365 printk(KERN_NOTICE "executable not page aligned\n");
366 error_time2 = jiffies;
369 if ((fd_offset & ~PAGE_MASK) != 0 &&
370 time_after(jiffies, error_time + 5*HZ)) {
372 "fd_offset is not page aligned. Please convert "
374 bprm->file->f_path.dentry->d_name.name);
375 error_time = jiffies;
379 if (!bprm->file->f_op->mmap || (fd_offset & ~PAGE_MASK) != 0) {
380 loff_t pos = fd_offset;
382 down_write(¤t->mm->mmap_sem);
383 do_brk(N_TXTADDR(ex), ex.a_text+ex.a_data);
384 up_write(¤t->mm->mmap_sem);
385 bprm->file->f_op->read(bprm->file,
386 (char __user *)N_TXTADDR(ex),
387 ex.a_text+ex.a_data, &pos);
388 flush_icache_range((unsigned long) N_TXTADDR(ex),
389 (unsigned long) N_TXTADDR(ex) +
390 ex.a_text+ex.a_data);
394 down_write(¤t->mm->mmap_sem);
395 error = do_mmap(bprm->file, N_TXTADDR(ex), ex.a_text,
396 PROT_READ | PROT_EXEC,
397 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE |
398 MAP_EXECUTABLE | MAP_32BIT,
400 up_write(¤t->mm->mmap_sem);
402 if (error != N_TXTADDR(ex)) {
403 send_sig(SIGKILL, current, 0);
407 down_write(¤t->mm->mmap_sem);
408 error = do_mmap(bprm->file, N_DATADDR(ex), ex.a_data,
409 PROT_READ | PROT_WRITE | PROT_EXEC,
410 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE |
411 MAP_EXECUTABLE | MAP_32BIT,
412 fd_offset + ex.a_text);
413 up_write(¤t->mm->mmap_sem);
414 if (error != N_DATADDR(ex)) {
415 send_sig(SIGKILL, current, 0);
420 set_binfmt(&aout_format);
422 set_brk(current->mm->start_brk, current->mm->brk);
424 retval = setup_arg_pages(bprm, IA32_STACK_TOP, EXSTACK_DEFAULT);
426 /* Someone check-me: is this error path enough? */
427 send_sig(SIGKILL, current, 0);
431 current->mm->start_stack =
432 (unsigned long)create_aout_tables((char __user *)bprm->p, bprm);
435 loadsegment(ds, __USER32_DS);
436 loadsegment(es, __USER32_DS);
438 (regs)->ip = ex.a_entry;
439 (regs)->sp = current->mm->start_stack;
440 (regs)->flags = 0x200;
441 (regs)->cs = __USER32_CS;
442 (regs)->ss = __USER32_DS;
443 regs->r8 = regs->r9 = regs->r10 = regs->r11 =
444 regs->r12 = regs->r13 = regs->r14 = regs->r15 = 0;
449 static int load_aout_library(struct file *file)
452 unsigned long bss, start_addr, len, error;
456 inode = file->f_path.dentry->d_inode;
459 error = kernel_read(file, 0, (char *) &ex, sizeof(ex));
460 if (error != sizeof(ex))
463 /* We come in here for the regular a.out style of shared libraries */
464 if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != QMAGIC) || N_TRSIZE(ex) ||
465 N_DRSIZE(ex) || ((ex.a_entry & 0xfff) && N_MAGIC(ex) == ZMAGIC) ||
467 ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
474 /* For QMAGIC, the starting address is 0x20 into the page. We mask
475 this off to get the starting address for the page */
477 start_addr = ex.a_entry & 0xfffff000;
479 if ((N_TXTOFF(ex) & ~PAGE_MASK) != 0) {
480 loff_t pos = N_TXTOFF(ex);
483 static unsigned long error_time;
484 if (time_after(jiffies, error_time + 5*HZ)) {
486 "N_TXTOFF is not page aligned. Please convert "
488 file->f_path.dentry->d_name.name);
489 error_time = jiffies;
492 down_write(¤t->mm->mmap_sem);
493 do_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);
494 up_write(¤t->mm->mmap_sem);
496 file->f_op->read(file, (char __user *)start_addr,
497 ex.a_text + ex.a_data, &pos);
498 flush_icache_range((unsigned long) start_addr,
499 (unsigned long) start_addr + ex.a_text +
505 /* Now use mmap to map the library into memory. */
506 down_write(¤t->mm->mmap_sem);
507 error = do_mmap(file, start_addr, ex.a_text + ex.a_data,
508 PROT_READ | PROT_WRITE | PROT_EXEC,
509 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_32BIT,
511 up_write(¤t->mm->mmap_sem);
513 if (error != start_addr)
516 len = PAGE_ALIGN(ex.a_text + ex.a_data);
517 bss = ex.a_text + ex.a_data + ex.a_bss;
519 down_write(¤t->mm->mmap_sem);
520 error = do_brk(start_addr + len, bss - len);
521 up_write(¤t->mm->mmap_sem);
523 if (error != start_addr + len)
531 static int __init init_aout_binfmt(void)
533 return register_binfmt(&aout_format);
536 static void __exit exit_aout_binfmt(void)
538 unregister_binfmt(&aout_format);
541 module_init(init_aout_binfmt);
542 module_exit(exit_aout_binfmt);
543 MODULE_LICENSE("GPL");