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>
35 #include <asm/a.out-core.h>
37 static int load_aout32_binary(struct linux_binprm *, struct pt_regs * regs);
38 static int load_aout32_library(struct file*);
39 static int aout32_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit);
41 static struct linux_binfmt aout32_format = {
42 .module = THIS_MODULE,
43 .load_binary = load_aout32_binary,
44 .load_shlib = load_aout32_library,
45 .core_dump = aout32_core_dump,
46 .min_coredump = PAGE_SIZE,
49 static void set_brk(unsigned long start, unsigned long end)
51 start = PAGE_ALIGN(start);
52 end = PAGE_ALIGN(end);
55 down_write(¤t->mm->mmap_sem);
56 do_brk(start, end - start);
57 up_write(¤t->mm->mmap_sem);
61 * These are the only things you should do on a core-file: use only these
62 * macros to write out all the necessary info.
65 static int dump_write(struct file *file, const void *addr, int nr)
67 return file->f_op->write(file, addr, nr, &file->f_pos) == nr;
70 #define DUMP_WRITE(addr, nr) \
71 if (!dump_write(file, (void *)(addr), (nr))) \
74 #define DUMP_SEEK(offset) \
75 if (file->f_op->llseek) { \
76 if (file->f_op->llseek(file,(offset),0) != (offset)) \
78 } else file->f_pos = (offset)
81 * Routine writes a core dump image in the current directory.
82 * Currently only a stub-function.
84 * Note that setuid/setgid files won't make a core-dump if the uid/gid
85 * changed due to the set[u|g]id. It's enforced by the "current->mm->dumpable"
86 * field, which also makes sure the core-dumps won't be recursive if the
87 * dumping of the process results in another error..
90 static int aout32_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit)
94 unsigned long dump_start, dump_size;
96 # define START_DATA(u) (u.u_tsize)
97 # define START_STACK(u) ((regs->u_regs[UREG_FP]) & ~(PAGE_SIZE - 1))
102 current->flags |= PF_DUMPCORE;
103 strncpy(dump.u_comm, current->comm, sizeof(dump.u_comm));
105 aout_dump_thread(regs, &dump);
107 /* If the size of the dump file exceeds the rlimit, then see what would happen
108 if we wrote the stack, but not the data area. */
109 if (dump.u_dsize + dump.u_ssize > limit)
112 /* Make sure we have enough room to write the stack and data areas. */
113 if (dump.u_ssize > limit)
116 /* make sure we actually have a data and stack area to dump */
118 if (!access_ok(VERIFY_READ, (void __user *) START_DATA(dump), dump.u_dsize))
120 if (!access_ok(VERIFY_READ, (void __user *) START_STACK(dump), dump.u_ssize))
125 DUMP_WRITE(&dump,sizeof(dump));
126 /* now we start writing out the user space info */
128 /* Dump the data area */
129 if (dump.u_dsize != 0) {
130 dump_start = START_DATA(dump);
131 dump_size = dump.u_dsize;
132 DUMP_WRITE(dump_start,dump_size);
134 /* Now prepare to dump the stack area */
135 if (dump.u_ssize != 0) {
136 dump_start = START_STACK(dump);
137 dump_size = dump.u_ssize;
138 DUMP_WRITE(dump_start,dump_size);
140 /* Finally dump the task struct. Not be used by gdb, but could be useful */
142 DUMP_WRITE(current,sizeof(*current));
149 * create_aout32_tables() parses the env- and arg-strings in new user
150 * memory and creates the pointer tables from them, and puts their
151 * addresses on the "stack", returning the new stack pointer value.
154 static u32 __user *create_aout32_tables(char __user *p, struct linux_binprm *bprm)
159 int argc = bprm->argc;
160 int envc = bprm->envc;
162 sp = (u32 __user *)((-(unsigned long)sizeof(char *))&(unsigned long)p);
164 /* This imposes the proper stack alignment for a new process. */
165 sp = (u32 __user *) (((unsigned long) sp) & ~7);
174 current->mm->arg_start = (unsigned long) p;
177 put_user(((u32)(unsigned long)(p)),argv++);
183 current->mm->arg_end = current->mm->env_start = (unsigned long) p;
186 put_user(((u32)(unsigned long)(p)),envp++);
192 current->mm->env_end = (unsigned long) p;
197 * These are the functions used to load a.out style executables and shared
198 * libraries. There is no binary dependent code anywhere else.
201 static int load_aout32_binary(struct linux_binprm * bprm, struct pt_regs * regs)
205 unsigned long fd_offset;
207 unsigned long orig_thr_flags;
210 ex = *((struct exec *) bprm->buf); /* exec-header */
211 if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != OMAGIC &&
212 N_MAGIC(ex) != QMAGIC && N_MAGIC(ex) != NMAGIC) ||
213 N_TRSIZE(ex) || N_DRSIZE(ex) ||
214 bprm->file->f_path.dentry->d_inode->i_size < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
218 fd_offset = N_TXTOFF(ex);
220 /* Check initial limits. This avoids letting people circumvent
221 * size limits imposed on them by creating programs with large
222 * arrays in the data or bss.
224 rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
225 if (rlim >= RLIM_INFINITY)
227 if (ex.a_data + ex.a_bss > rlim)
230 /* Flush all traces of the currently running executable */
231 retval = flush_old_exec(bprm);
235 /* OK, This is the point of no return */
236 set_personality(PER_SUNOS);
238 current->mm->end_code = ex.a_text +
239 (current->mm->start_code = N_TXTADDR(ex));
240 current->mm->end_data = ex.a_data +
241 (current->mm->start_data = N_DATADDR(ex));
242 current->mm->brk = ex.a_bss +
243 (current->mm->start_brk = N_BSSADDR(ex));
244 current->mm->free_area_cache = current->mm->mmap_base;
245 current->mm->cached_hole_size = 0;
247 current->mm->mmap = NULL;
249 current->flags &= ~PF_FORKNOEXEC;
250 if (N_MAGIC(ex) == NMAGIC) {
251 loff_t pos = fd_offset;
252 /* Fuck me plenty... */
253 down_write(¤t->mm->mmap_sem);
254 error = do_brk(N_TXTADDR(ex), ex.a_text);
255 up_write(¤t->mm->mmap_sem);
256 bprm->file->f_op->read(bprm->file, (char __user *)N_TXTADDR(ex),
258 down_write(¤t->mm->mmap_sem);
259 error = do_brk(N_DATADDR(ex), ex.a_data);
260 up_write(¤t->mm->mmap_sem);
261 bprm->file->f_op->read(bprm->file, (char __user *)N_DATADDR(ex),
266 if (N_MAGIC(ex) == OMAGIC) {
267 loff_t pos = fd_offset;
268 down_write(¤t->mm->mmap_sem);
269 do_brk(N_TXTADDR(ex) & PAGE_MASK,
270 ex.a_text+ex.a_data + PAGE_SIZE - 1);
271 up_write(¤t->mm->mmap_sem);
272 bprm->file->f_op->read(bprm->file, (char __user *)N_TXTADDR(ex),
273 ex.a_text+ex.a_data, &pos);
275 static unsigned long error_time;
276 if ((ex.a_text & 0xfff || ex.a_data & 0xfff) &&
277 (N_MAGIC(ex) != NMAGIC) && (jiffies-error_time) > 5*HZ)
279 printk(KERN_NOTICE "executable not page aligned\n");
280 error_time = jiffies;
283 if (!bprm->file->f_op->mmap) {
284 loff_t pos = fd_offset;
285 down_write(¤t->mm->mmap_sem);
286 do_brk(0, ex.a_text+ex.a_data);
287 up_write(¤t->mm->mmap_sem);
288 bprm->file->f_op->read(bprm->file,
289 (char __user *)N_TXTADDR(ex),
290 ex.a_text+ex.a_data, &pos);
294 down_write(¤t->mm->mmap_sem);
295 error = do_mmap(bprm->file, N_TXTADDR(ex), ex.a_text,
296 PROT_READ | PROT_EXEC,
297 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE,
299 up_write(¤t->mm->mmap_sem);
301 if (error != N_TXTADDR(ex)) {
302 send_sig(SIGKILL, current, 0);
306 down_write(¤t->mm->mmap_sem);
307 error = do_mmap(bprm->file, N_DATADDR(ex), ex.a_data,
308 PROT_READ | PROT_WRITE | PROT_EXEC,
309 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE,
310 fd_offset + ex.a_text);
311 up_write(¤t->mm->mmap_sem);
312 if (error != N_DATADDR(ex)) {
313 send_sig(SIGKILL, current, 0);
318 set_binfmt(&aout32_format);
320 set_brk(current->mm->start_brk, current->mm->brk);
322 /* Make sure STACK_TOP returns the right thing. */
323 orig_thr_flags = current_thread_info()->flags;
324 current_thread_info()->flags |= _TIF_32BIT;
326 retval = setup_arg_pages(bprm, STACK_TOP, EXSTACK_DEFAULT);
328 current_thread_info()->flags = orig_thr_flags;
330 /* Someone check-me: is this error path enough? */
331 send_sig(SIGKILL, current, 0);
335 current->mm->start_stack =
336 (unsigned long) create_aout32_tables((char __user *)bprm->p, bprm);
337 tsb_context_switch(current->mm);
339 start_thread32(regs, ex.a_entry, current->mm->start_stack);
340 if (current->ptrace & PT_PTRACED)
341 send_sig(SIGTRAP, current, 0);
345 /* N.B. Move to .h file and use code in fs/binfmt_aout.c? */
346 static int load_aout32_library(struct file *file)
348 struct inode * inode;
349 unsigned long bss, start_addr, len;
354 inode = file->f_path.dentry->d_inode;
357 error = kernel_read(file, 0, (char *) &ex, sizeof(ex));
358 if (error != sizeof(ex))
361 /* We come in here for the regular a.out style of shared libraries */
362 if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != QMAGIC) || N_TRSIZE(ex) ||
363 N_DRSIZE(ex) || ((ex.a_entry & 0xfff) && N_MAGIC(ex) == ZMAGIC) ||
364 inode->i_size < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
368 if (N_MAGIC(ex) == ZMAGIC && N_TXTOFF(ex) &&
369 (N_TXTOFF(ex) < inode->i_sb->s_blocksize)) {
370 printk("N_TXTOFF < BLOCK_SIZE. Please convert library\n");
377 /* For QMAGIC, the starting address is 0x20 into the page. We mask
378 this off to get the starting address for the page */
380 start_addr = ex.a_entry & 0xfffff000;
382 /* Now use mmap to map the library into memory. */
383 down_write(¤t->mm->mmap_sem);
384 error = do_mmap(file, start_addr, ex.a_text + ex.a_data,
385 PROT_READ | PROT_WRITE | PROT_EXEC,
386 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE,
388 up_write(¤t->mm->mmap_sem);
390 if (error != start_addr)
393 len = PAGE_ALIGN(ex.a_text + ex.a_data);
394 bss = ex.a_text + ex.a_data + ex.a_bss;
396 down_write(¤t->mm->mmap_sem);
397 error = do_brk(start_addr + len, bss - len);
398 up_write(¤t->mm->mmap_sem);
400 if (error != start_addr + len)
408 static int __init init_aout32_binfmt(void)
410 return register_binfmt(&aout32_format);
413 static void __exit exit_aout32_binfmt(void)
415 unregister_binfmt(&aout32_format);
418 module_init(init_aout32_binfmt);
419 module_exit(exit_aout32_binfmt);