| /* |
| * linux/fs/binfmt_aout.c |
| * |
| * Copyright (C) 1991, 1992, 1996 Linus Torvalds |
| * |
| * Hacked a bit by DaveM to make it work with 32-bit SunOS |
| * binaries on the sparc64 port. |
| */ |
| |
| #include <linux/module.h> |
| |
| #include <linux/sched.h> |
| #include <linux/kernel.h> |
| #include <linux/mm.h> |
| #include <linux/mman.h> |
| #include <linux/a.out.h> |
| #include <linux/errno.h> |
| #include <linux/signal.h> |
| #include <linux/string.h> |
| #include <linux/fs.h> |
| #include <linux/file.h> |
| #include <linux/stat.h> |
| #include <linux/fcntl.h> |
| #include <linux/ptrace.h> |
| #include <linux/user.h> |
| #include <linux/slab.h> |
| #include <linux/binfmts.h> |
| #include <linux/personality.h> |
| #include <linux/init.h> |
| |
| #include <asm/system.h> |
| #include <asm/uaccess.h> |
| #include <asm/pgalloc.h> |
| #include <asm/mmu_context.h> |
| |
| static int load_aout32_binary(struct linux_binprm *, struct pt_regs * regs); |
| static int load_aout32_library(struct file*); |
| static int aout32_core_dump(long signr, struct pt_regs * regs, struct file *file); |
| |
| static struct linux_binfmt aout32_format = { |
| NULL, THIS_MODULE, load_aout32_binary, load_aout32_library, aout32_core_dump, |
| PAGE_SIZE |
| }; |
| |
| static void set_brk(unsigned long start, unsigned long end) |
| { |
| start = PAGE_ALIGN(start); |
| end = PAGE_ALIGN(end); |
| if (end <= start) |
| return; |
| down_write(¤t->mm->mmap_sem); |
| do_brk(start, end - start); |
| up_write(¤t->mm->mmap_sem); |
| } |
| |
| /* |
| * These are the only things you should do on a core-file: use only these |
| * macros to write out all the necessary info. |
| */ |
| |
| static int dump_write(struct file *file, const void *addr, int nr) |
| { |
| return file->f_op->write(file, addr, nr, &file->f_pos) == nr; |
| } |
| |
| #define DUMP_WRITE(addr, nr) \ |
| if (!dump_write(file, (void *)(addr), (nr))) \ |
| goto end_coredump; |
| |
| #define DUMP_SEEK(offset) \ |
| if (file->f_op->llseek) { \ |
| if (file->f_op->llseek(file,(offset),0) != (offset)) \ |
| goto end_coredump; \ |
| } else file->f_pos = (offset) |
| |
| /* |
| * Routine writes a core dump image in the current directory. |
| * Currently only a stub-function. |
| * |
| * Note that setuid/setgid files won't make a core-dump if the uid/gid |
| * changed due to the set[u|g]id. It's enforced by the "current->mm->dumpable" |
| * field, which also makes sure the core-dumps won't be recursive if the |
| * dumping of the process results in another error.. |
| */ |
| |
| static int aout32_core_dump(long signr, struct pt_regs *regs, struct file *file) |
| { |
| mm_segment_t fs; |
| int has_dumped = 0; |
| unsigned long dump_start, dump_size; |
| struct user dump; |
| # define START_DATA(u) (u.u_tsize) |
| # define START_STACK(u) ((regs->u_regs[UREG_FP]) & ~(PAGE_SIZE - 1)) |
| |
| fs = get_fs(); |
| set_fs(KERNEL_DS); |
| has_dumped = 1; |
| current->flags |= PF_DUMPCORE; |
| strncpy(dump.u_comm, current->comm, sizeof(dump.u_comm)); |
| dump.signal = signr; |
| dump_thread(regs, &dump); |
| |
| /* If the size of the dump file exceeds the rlimit, then see what would happen |
| if we wrote the stack, but not the data area. */ |
| if ((dump.u_dsize+dump.u_ssize) > |
| current->signal->rlim[RLIMIT_CORE].rlim_cur) |
| dump.u_dsize = 0; |
| |
| /* Make sure we have enough room to write the stack and data areas. */ |
| if ((dump.u_ssize) > |
| current->signal->rlim[RLIMIT_CORE].rlim_cur) |
| dump.u_ssize = 0; |
| |
| /* make sure we actually have a data and stack area to dump */ |
| set_fs(USER_DS); |
| if (!access_ok(VERIFY_READ, (void __user *) START_DATA(dump), dump.u_dsize)) |
| dump.u_dsize = 0; |
| if (!access_ok(VERIFY_READ, (void __user *) START_STACK(dump), dump.u_ssize)) |
| dump.u_ssize = 0; |
| |
| set_fs(KERNEL_DS); |
| /* struct user */ |
| DUMP_WRITE(&dump,sizeof(dump)); |
| /* now we start writing out the user space info */ |
| set_fs(USER_DS); |
| /* Dump the data area */ |
| if (dump.u_dsize != 0) { |
| dump_start = START_DATA(dump); |
| dump_size = dump.u_dsize; |
| DUMP_WRITE(dump_start,dump_size); |
| } |
| /* Now prepare to dump the stack area */ |
| if (dump.u_ssize != 0) { |
| dump_start = START_STACK(dump); |
| dump_size = dump.u_ssize; |
| DUMP_WRITE(dump_start,dump_size); |
| } |
| /* Finally dump the task struct. Not be used by gdb, but could be useful */ |
| set_fs(KERNEL_DS); |
| DUMP_WRITE(current,sizeof(*current)); |
| end_coredump: |
| set_fs(fs); |
| return has_dumped; |
| } |
| |
| /* |
| * create_aout32_tables() parses the env- and arg-strings in new user |
| * memory and creates the pointer tables from them, and puts their |
| * addresses on the "stack", returning the new stack pointer value. |
| */ |
| |
| static u32 __user *create_aout32_tables(char __user *p, struct linux_binprm *bprm) |
| { |
| u32 __user *argv; |
| u32 __user *envp; |
| u32 __user *sp; |
| int argc = bprm->argc; |
| int envc = bprm->envc; |
| |
| sp = (u32 __user *)((-(unsigned long)sizeof(char *))&(unsigned long)p); |
| |
| /* This imposes the proper stack alignment for a new process. */ |
| sp = (u32 __user *) (((unsigned long) sp) & ~7); |
| if ((envc+argc+3)&1) |
| --sp; |
| |
| sp -= envc+1; |
| envp = sp; |
| sp -= argc+1; |
| argv = sp; |
| put_user(argc,--sp); |
| current->mm->arg_start = (unsigned long) p; |
| while (argc-->0) { |
| char c; |
| put_user(((u32)(unsigned long)(p)),argv++); |
| do { |
| get_user(c,p++); |
| } while (c); |
| } |
| put_user(0,argv); |
| current->mm->arg_end = current->mm->env_start = (unsigned long) p; |
| while (envc-->0) { |
| char c; |
| put_user(((u32)(unsigned long)(p)),envp++); |
| do { |
| get_user(c,p++); |
| } while (c); |
| } |
| put_user(0,envp); |
| current->mm->env_end = (unsigned long) p; |
| return sp; |
| } |
| |
| /* |
| * These are the functions used to load a.out style executables and shared |
| * libraries. There is no binary dependent code anywhere else. |
| */ |
| |
| static int load_aout32_binary(struct linux_binprm * bprm, struct pt_regs * regs) |
| { |
| struct exec ex; |
| unsigned long error; |
| unsigned long fd_offset; |
| unsigned long rlim; |
| unsigned long orig_thr_flags; |
| int retval; |
| |
| ex = *((struct exec *) bprm->buf); /* exec-header */ |
| if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != OMAGIC && |
| N_MAGIC(ex) != QMAGIC && N_MAGIC(ex) != NMAGIC) || |
| N_TRSIZE(ex) || N_DRSIZE(ex) || |
| bprm->file->f_path.dentry->d_inode->i_size < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) { |
| return -ENOEXEC; |
| } |
| |
| fd_offset = N_TXTOFF(ex); |
| |
| /* Check initial limits. This avoids letting people circumvent |
| * size limits imposed on them by creating programs with large |
| * arrays in the data or bss. |
| */ |
| rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur; |
| if (rlim >= RLIM_INFINITY) |
| rlim = ~0; |
| if (ex.a_data + ex.a_bss > rlim) |
| return -ENOMEM; |
| |
| /* Flush all traces of the currently running executable */ |
| retval = flush_old_exec(bprm); |
| if (retval) |
| return retval; |
| |
| /* OK, This is the point of no return */ |
| set_personality(PER_SUNOS); |
| |
| current->mm->end_code = ex.a_text + |
| (current->mm->start_code = N_TXTADDR(ex)); |
| current->mm->end_data = ex.a_data + |
| (current->mm->start_data = N_DATADDR(ex)); |
| current->mm->brk = ex.a_bss + |
| (current->mm->start_brk = N_BSSADDR(ex)); |
| current->mm->free_area_cache = current->mm->mmap_base; |
| current->mm->cached_hole_size = 0; |
| |
| current->mm->mmap = NULL; |
| compute_creds(bprm); |
| current->flags &= ~PF_FORKNOEXEC; |
| if (N_MAGIC(ex) == NMAGIC) { |
| loff_t pos = fd_offset; |
| /* Fuck me plenty... */ |
| down_write(¤t->mm->mmap_sem); |
| error = do_brk(N_TXTADDR(ex), ex.a_text); |
| up_write(¤t->mm->mmap_sem); |
| bprm->file->f_op->read(bprm->file, (char __user *)N_TXTADDR(ex), |
| ex.a_text, &pos); |
| down_write(¤t->mm->mmap_sem); |
| error = do_brk(N_DATADDR(ex), ex.a_data); |
| up_write(¤t->mm->mmap_sem); |
| bprm->file->f_op->read(bprm->file, (char __user *)N_DATADDR(ex), |
| ex.a_data, &pos); |
| goto beyond_if; |
| } |
| |
| if (N_MAGIC(ex) == OMAGIC) { |
| loff_t pos = fd_offset; |
| down_write(¤t->mm->mmap_sem); |
| do_brk(N_TXTADDR(ex) & PAGE_MASK, |
| ex.a_text+ex.a_data + PAGE_SIZE - 1); |
| up_write(¤t->mm->mmap_sem); |
| bprm->file->f_op->read(bprm->file, (char __user *)N_TXTADDR(ex), |
| ex.a_text+ex.a_data, &pos); |
| } else { |
| static unsigned long error_time; |
| if ((ex.a_text & 0xfff || ex.a_data & 0xfff) && |
| (N_MAGIC(ex) != NMAGIC) && (jiffies-error_time) > 5*HZ) |
| { |
| printk(KERN_NOTICE "executable not page aligned\n"); |
| error_time = jiffies; |
| } |
| |
| if (!bprm->file->f_op->mmap) { |
| loff_t pos = fd_offset; |
| down_write(¤t->mm->mmap_sem); |
| do_brk(0, ex.a_text+ex.a_data); |
| up_write(¤t->mm->mmap_sem); |
| bprm->file->f_op->read(bprm->file, |
| (char __user *)N_TXTADDR(ex), |
| ex.a_text+ex.a_data, &pos); |
| goto beyond_if; |
| } |
| |
| down_write(¤t->mm->mmap_sem); |
| error = do_mmap(bprm->file, N_TXTADDR(ex), ex.a_text, |
| PROT_READ | PROT_EXEC, |
| MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE, |
| fd_offset); |
| up_write(¤t->mm->mmap_sem); |
| |
| if (error != N_TXTADDR(ex)) { |
| send_sig(SIGKILL, current, 0); |
| return error; |
| } |
| |
| down_write(¤t->mm->mmap_sem); |
| error = do_mmap(bprm->file, N_DATADDR(ex), ex.a_data, |
| PROT_READ | PROT_WRITE | PROT_EXEC, |
| MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE, |
| fd_offset + ex.a_text); |
| up_write(¤t->mm->mmap_sem); |
| if (error != N_DATADDR(ex)) { |
| send_sig(SIGKILL, current, 0); |
| return error; |
| } |
| } |
| beyond_if: |
| set_binfmt(&aout32_format); |
| |
| set_brk(current->mm->start_brk, current->mm->brk); |
| |
| /* Make sure STACK_TOP returns the right thing. */ |
| orig_thr_flags = current_thread_info()->flags; |
| current_thread_info()->flags |= _TIF_32BIT; |
| |
| retval = setup_arg_pages(bprm, STACK_TOP, EXSTACK_DEFAULT); |
| if (retval < 0) { |
| current_thread_info()->flags = orig_thr_flags; |
| |
| /* Someone check-me: is this error path enough? */ |
| send_sig(SIGKILL, current, 0); |
| return retval; |
| } |
| |
| current->mm->start_stack = |
| (unsigned long) create_aout32_tables((char __user *)bprm->p, bprm); |
| tsb_context_switch(current->mm); |
| |
| start_thread32(regs, ex.a_entry, current->mm->start_stack); |
| if (current->ptrace & PT_PTRACED) |
| send_sig(SIGTRAP, current, 0); |
| return 0; |
| } |
| |
| /* N.B. Move to .h file and use code in fs/binfmt_aout.c? */ |
| static int load_aout32_library(struct file *file) |
| { |
| struct inode * inode; |
| unsigned long bss, start_addr, len; |
| unsigned long error; |
| int retval; |
| struct exec ex; |
| |
| inode = file->f_path.dentry->d_inode; |
| |
| retval = -ENOEXEC; |
| error = kernel_read(file, 0, (char *) &ex, sizeof(ex)); |
| if (error != sizeof(ex)) |
| goto out; |
| |
| /* We come in here for the regular a.out style of shared libraries */ |
| if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != QMAGIC) || N_TRSIZE(ex) || |
| N_DRSIZE(ex) || ((ex.a_entry & 0xfff) && N_MAGIC(ex) == ZMAGIC) || |
| inode->i_size < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) { |
| goto out; |
| } |
| |
| if (N_MAGIC(ex) == ZMAGIC && N_TXTOFF(ex) && |
| (N_TXTOFF(ex) < inode->i_sb->s_blocksize)) { |
| printk("N_TXTOFF < BLOCK_SIZE. Please convert library\n"); |
| goto out; |
| } |
| |
| if (N_FLAGS(ex)) |
| goto out; |
| |
| /* For QMAGIC, the starting address is 0x20 into the page. We mask |
| this off to get the starting address for the page */ |
| |
| start_addr = ex.a_entry & 0xfffff000; |
| |
| /* Now use mmap to map the library into memory. */ |
| down_write(¤t->mm->mmap_sem); |
| error = do_mmap(file, start_addr, ex.a_text + ex.a_data, |
| PROT_READ | PROT_WRITE | PROT_EXEC, |
| MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE, |
| N_TXTOFF(ex)); |
| up_write(¤t->mm->mmap_sem); |
| retval = error; |
| if (error != start_addr) |
| goto out; |
| |
| len = PAGE_ALIGN(ex.a_text + ex.a_data); |
| bss = ex.a_text + ex.a_data + ex.a_bss; |
| if (bss > len) { |
| down_write(¤t->mm->mmap_sem); |
| error = do_brk(start_addr + len, bss - len); |
| up_write(¤t->mm->mmap_sem); |
| retval = error; |
| if (error != start_addr + len) |
| goto out; |
| } |
| retval = 0; |
| out: |
| return retval; |
| } |
| |
| static int __init init_aout32_binfmt(void) |
| { |
| return register_binfmt(&aout32_format); |
| } |
| |
| static void __exit exit_aout32_binfmt(void) |
| { |
| unregister_binfmt(&aout32_format); |
| } |
| |
| module_init(init_aout32_binfmt); |
| module_exit(exit_aout32_binfmt); |