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/slab.h>
25 #include <linux/binfmts.h>
26 #include <linux/personality.h>
27 #include <linux/init.h>
28 #include <linux/vs_memory.h>
30 #include <asm/system.h>
31 #include <asm/uaccess.h>
32 #include <asm/pgalloc.h>
33 #include <asm/cacheflush.h>
34 #include <asm/user32.h>
38 #undef CORE_DUMP /* probably broken */
40 extern int ia32_setup_arg_pages(struct linux_binprm *bprm,
41 unsigned long stack_top, int exec_stack);
43 static int load_aout_binary(struct linux_binprm *, struct pt_regs * regs);
44 static int load_aout_library(struct file*);
47 static int aout_core_dump(long signr, struct pt_regs * regs, struct file *file);
50 * fill in the user structure for a core dump..
52 static void dump_thread32(struct pt_regs * regs, struct user32 * dump)
56 /* changed the size calculations - should hopefully work better. lbt */
59 dump->start_stack = regs->rsp & ~(PAGE_SIZE - 1);
60 dump->u_tsize = ((unsigned long) current->mm->end_code) >> PAGE_SHIFT;
61 dump->u_dsize = ((unsigned long) (current->mm->brk + (PAGE_SIZE-1))) >> PAGE_SHIFT;
62 dump->u_dsize -= dump->u_tsize;
64 dump->u_debugreg[0] = current->thread.debugreg0;
65 dump->u_debugreg[1] = current->thread.debugreg1;
66 dump->u_debugreg[2] = current->thread.debugreg2;
67 dump->u_debugreg[3] = current->thread.debugreg3;
68 dump->u_debugreg[4] = 0;
69 dump->u_debugreg[5] = 0;
70 dump->u_debugreg[6] = current->thread.debugreg6;
71 dump->u_debugreg[7] = current->thread.debugreg7;
73 if (dump->start_stack < 0xc0000000)
74 dump->u_ssize = ((unsigned long) (0xc0000000 - dump->start_stack)) >> PAGE_SHIFT;
76 dump->regs.ebx = regs->rbx;
77 dump->regs.ecx = regs->rcx;
78 dump->regs.edx = regs->rdx;
79 dump->regs.esi = regs->rsi;
80 dump->regs.edi = regs->rdi;
81 dump->regs.ebp = regs->rbp;
82 dump->regs.eax = regs->rax;
83 dump->regs.ds = current->thread.ds;
84 dump->regs.es = current->thread.es;
85 asm("movl %%fs,%0" : "=r" (fs)); dump->regs.fs = fs;
86 asm("movl %%gs,%0" : "=r" (gs)); dump->regs.gs = gs;
87 dump->regs.orig_eax = regs->orig_rax;
88 dump->regs.eip = regs->rip;
89 dump->regs.cs = regs->cs;
90 dump->regs.eflags = regs->eflags;
91 dump->regs.esp = regs->rsp;
92 dump->regs.ss = regs->ss;
97 dump->u_fpvalid = dump_fpu (regs, &dump->i387);
103 static struct linux_binfmt aout_format = {
104 .module = THIS_MODULE,
105 .load_binary = load_aout_binary,
106 .load_shlib = load_aout_library,
108 .core_dump = aout_core_dump,
110 .min_coredump = PAGE_SIZE
113 static void set_brk(unsigned long start, unsigned long end)
115 start = PAGE_ALIGN(start);
116 end = PAGE_ALIGN(end);
119 down_write(¤t->mm->mmap_sem);
120 do_brk(start, end - start);
121 up_write(¤t->mm->mmap_sem);
126 * These are the only things you should do on a core-file: use only these
127 * macros to write out all the necessary info.
130 static int dump_write(struct file *file, const void *addr, int nr)
132 return file->f_op->write(file, addr, nr, &file->f_pos) == nr;
135 #define DUMP_WRITE(addr, nr) \
136 if (!dump_write(file, (void *)(addr), (nr))) \
139 #define DUMP_SEEK(offset) \
140 if (file->f_op->llseek) { \
141 if (file->f_op->llseek(file,(offset),0) != (offset)) \
143 } else file->f_pos = (offset)
146 * Routine writes a core dump image in the current directory.
147 * Currently only a stub-function.
149 * Note that setuid/setgid files won't make a core-dump if the uid/gid
150 * changed due to the set[u|g]id. It's enforced by the "current->mm->dumpable"
151 * field, which also makes sure the core-dumps won't be recursive if the
152 * dumping of the process results in another error..
155 static int aout_core_dump(long signr, struct pt_regs * regs, struct file *file)
159 unsigned long dump_start, dump_size;
161 # define START_DATA(u) (u.u_tsize << PAGE_SHIFT)
162 # define START_STACK(u) (u.start_stack)
167 current->flags |= PF_DUMPCORE;
168 strncpy(dump.u_comm, current->comm, sizeof(current->comm));
169 dump.u_ar0 = (u32)(((unsigned long)(&dump.regs)) - ((unsigned long)(&dump)));
171 dump_thread32(regs, &dump);
173 /* If the size of the dump file exceeds the rlimit, then see what would happen
174 if we wrote the stack, but not the data area. */
175 if ((dump.u_dsize+dump.u_ssize+1) * PAGE_SIZE >
176 current->signal->rlim[RLIMIT_CORE].rlim_cur)
179 /* Make sure we have enough room to write the stack and data areas. */
180 if ((dump.u_ssize+1) * PAGE_SIZE >
181 current->signal->rlim[RLIMIT_CORE].rlim_cur)
184 /* make sure we actually have a data and stack area to dump */
186 if (verify_area(VERIFY_READ, (void *) (unsigned long)START_DATA(dump), dump.u_dsize << PAGE_SHIFT))
188 if (verify_area(VERIFY_READ, (void *) (unsigned long)START_STACK(dump), dump.u_ssize << PAGE_SHIFT))
193 DUMP_WRITE(&dump,sizeof(dump));
194 /* Now dump all of the user data. Include malloced stuff as well */
195 DUMP_SEEK(PAGE_SIZE);
196 /* now we start writing out the user space info */
198 /* Dump the data area */
199 if (dump.u_dsize != 0) {
200 dump_start = START_DATA(dump);
201 dump_size = dump.u_dsize << PAGE_SHIFT;
202 DUMP_WRITE(dump_start,dump_size);
204 /* Now prepare to dump the stack area */
205 if (dump.u_ssize != 0) {
206 dump_start = START_STACK(dump);
207 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));
220 * create_aout_tables() parses the env- and arg-strings in new user
221 * memory and creates the pointer tables from them, and puts their
222 * addresses on the "stack", returning the new stack pointer value.
224 static u32 __user *create_aout_tables(char __user *p, struct linux_binprm *bprm)
229 int argc = bprm->argc;
230 int envc = bprm->envc;
232 sp = (u32 __user *) ((-(unsigned long)sizeof(u32)) & (unsigned long) p);
237 put_user((unsigned long) envp,--sp);
238 put_user((unsigned long) argv,--sp);
240 current->mm->arg_start = (unsigned long) p;
243 put_user((u32)(unsigned long)p,argv++);
249 current->mm->arg_end = current->mm->env_start = (unsigned long) p;
252 put_user((u32)(unsigned long)p,envp++);
258 current->mm->env_end = (unsigned long) p;
263 * These are the functions used to load a.out style executables and shared
264 * libraries. There is no binary dependent code anywhere else.
267 static int load_aout_binary(struct linux_binprm * bprm, struct pt_regs * regs)
271 unsigned long fd_offset;
275 ex = *((struct exec *) bprm->buf); /* exec-header */
276 if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != OMAGIC &&
277 N_MAGIC(ex) != QMAGIC && N_MAGIC(ex) != NMAGIC) ||
278 N_TRSIZE(ex) || N_DRSIZE(ex) ||
279 i_size_read(bprm->file->f_dentry->d_inode) < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
283 fd_offset = N_TXTOFF(ex);
285 /* Check initial limits. This avoids letting people circumvent
286 * size limits imposed on them by creating programs with large
287 * arrays in the data or bss.
289 rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
290 if (rlim >= RLIM_INFINITY)
292 if (ex.a_data + ex.a_bss > rlim)
295 /* Flush all traces of the currently running executable */
296 retval = flush_old_exec(bprm);
300 regs->cs = __USER32_CS;
301 regs->r8 = regs->r9 = regs->r10 = regs->r11 = regs->r12 =
302 regs->r13 = regs->r14 = regs->r15 = 0;
304 /* OK, This is the point of no return */
305 set_personality(PER_LINUX);
306 set_thread_flag(TIF_IA32);
307 clear_thread_flag(TIF_ABI_PENDING);
309 current->mm->end_code = ex.a_text +
310 (current->mm->start_code = N_TXTADDR(ex));
311 current->mm->end_data = ex.a_data +
312 (current->mm->start_data = N_DATADDR(ex));
313 current->mm->brk = ex.a_bss +
314 (current->mm->start_brk = N_BSSADDR(ex));
315 current->mm->free_area_cache = TASK_UNMAPPED_BASE;
317 // current->mm->rss = 0;
318 vx_rsspages_sub(current->mm, current->mm->rss);
319 current->mm->mmap = NULL;
321 current->flags &= ~PF_FORKNOEXEC;
323 if (N_MAGIC(ex) == OMAGIC) {
324 unsigned long text_addr, map_size;
327 text_addr = N_TXTADDR(ex);
330 map_size = ex.a_text+ex.a_data;
332 down_write(¤t->mm->mmap_sem);
333 error = do_brk(text_addr & PAGE_MASK, map_size);
334 up_write(¤t->mm->mmap_sem);
336 if (error != (text_addr & PAGE_MASK)) {
337 send_sig(SIGKILL, current, 0);
341 error = bprm->file->f_op->read(bprm->file, (char *)text_addr,
342 ex.a_text+ex.a_data, &pos);
343 if ((signed long)error < 0) {
344 send_sig(SIGKILL, current, 0);
348 flush_icache_range(text_addr, text_addr+ex.a_text+ex.a_data);
351 static unsigned long error_time, error_time2;
352 if ((ex.a_text & 0xfff || ex.a_data & 0xfff) &&
353 (N_MAGIC(ex) != NMAGIC) && (jiffies-error_time2) > 5*HZ)
355 printk(KERN_NOTICE "executable not page aligned\n");
356 error_time2 = jiffies;
359 if ((fd_offset & ~PAGE_MASK) != 0 &&
360 (jiffies-error_time) > 5*HZ)
363 "fd_offset is not page aligned. Please convert program: %s\n",
364 bprm->file->f_dentry->d_name.name);
365 error_time = jiffies;
369 if (!bprm->file->f_op->mmap||((fd_offset & ~PAGE_MASK) != 0)) {
370 loff_t pos = fd_offset;
371 down_write(¤t->mm->mmap_sem);
372 do_brk(N_TXTADDR(ex), ex.a_text+ex.a_data);
373 up_write(¤t->mm->mmap_sem);
374 bprm->file->f_op->read(bprm->file,(char *)N_TXTADDR(ex),
375 ex.a_text+ex.a_data, &pos);
376 flush_icache_range((unsigned long) N_TXTADDR(ex),
377 (unsigned long) N_TXTADDR(ex) +
378 ex.a_text+ex.a_data);
382 down_write(¤t->mm->mmap_sem);
383 error = do_mmap(bprm->file, N_TXTADDR(ex), ex.a_text,
384 PROT_READ | PROT_EXEC,
385 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE | MAP_32BIT,
387 up_write(¤t->mm->mmap_sem);
389 if (error != N_TXTADDR(ex)) {
390 send_sig(SIGKILL, current, 0);
394 down_write(¤t->mm->mmap_sem);
395 error = do_mmap(bprm->file, N_DATADDR(ex), ex.a_data,
396 PROT_READ | PROT_WRITE | PROT_EXEC,
397 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE | MAP_32BIT,
398 fd_offset + ex.a_text);
399 up_write(¤t->mm->mmap_sem);
400 if (error != N_DATADDR(ex)) {
401 send_sig(SIGKILL, current, 0);
406 set_binfmt(&aout_format);
408 set_brk(current->mm->start_brk, current->mm->brk);
410 retval = ia32_setup_arg_pages(bprm, IA32_STACK_TOP, EXSTACK_DEFAULT);
412 /* Someone check-me: is this error path enough? */
413 send_sig(SIGKILL, current, 0);
417 current->mm->start_stack =
418 (unsigned long)create_aout_tables((char __user *)bprm->p, bprm);
420 asm volatile("movl %0,%%fs" :: "r" (0)); \
421 asm volatile("movl %0,%%es; movl %0,%%ds": :"r" (__USER32_DS));
423 (regs)->rip = ex.a_entry;
424 (regs)->rsp = current->mm->start_stack;
425 (regs)->eflags = 0x200;
426 (regs)->cs = __USER32_CS;
427 (regs)->ss = __USER32_DS;
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 loff_t pos = N_TXTOFF(ex);
472 static unsigned long error_time;
473 if ((jiffies-error_time) > 5*HZ)
476 "N_TXTOFF is not page aligned. Please convert library: %s\n",
477 file->f_dentry->d_name.name);
478 error_time = jiffies;
481 down_write(¤t->mm->mmap_sem);
482 do_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);
483 up_write(¤t->mm->mmap_sem);
485 file->f_op->read(file, (char *)start_addr,
486 ex.a_text + ex.a_data, &pos);
487 flush_icache_range((unsigned long) start_addr,
488 (unsigned long) start_addr + ex.a_text + ex.a_data);
493 /* Now use mmap to map the library into memory. */
494 down_write(¤t->mm->mmap_sem);
495 error = do_mmap(file, start_addr, ex.a_text + ex.a_data,
496 PROT_READ | PROT_WRITE | PROT_EXEC,
497 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_32BIT,
499 up_write(¤t->mm->mmap_sem);
501 if (error != start_addr)
504 len = PAGE_ALIGN(ex.a_text + ex.a_data);
505 bss = ex.a_text + ex.a_data + ex.a_bss;
507 down_write(¤t->mm->mmap_sem);
508 error = do_brk(start_addr + len, bss - len);
509 up_write(¤t->mm->mmap_sem);
511 if (error != start_addr + len)
519 static int __init init_aout_binfmt(void)
521 return register_binfmt(&aout_format);
524 static void __exit exit_aout_binfmt(void)
526 unregister_binfmt(&aout_format);
529 module_init(init_aout_binfmt);
530 module_exit(exit_aout_binfmt);
531 MODULE_LICENSE("GPL");