Subversion Repositories or1k

/*

 *  linux/fs/binfmt_aout.c

 *

 *  Copyright (C) 1991, 1992, 1996  Linus Torvalds

 */

#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>

static int load_aout_binary(struct linux_binprm *, struct pt_regs * regs);

static int load_aout_library(struct file*);

static int aout_core_dump(long signr, struct pt_regs * regs, struct file *file);

extern void dump_thread(struct pt_regs *, struct user *);

static struct linux_binfmt aout_format = {

        NULL, THIS_MODULE, load_aout_binary, load_aout_library, aout_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;

        do_brk(start, end - start);

}

/*

 * 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 aout_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;

#if defined(__alpha__)

#       define START_DATA(u)    (u.start_data)

#elif defined(__arm__)

#       define START_DATA(u)    ((u.u_tsize << PAGE_SHIFT) + u.start_code)

#elif defined(__sparc__)

#       define START_DATA(u)    (u.u_tsize)

#elif defined(__i386__) || defined(__mc68000__) || defined(__arch_um__)

#       define START_DATA(u)    (u.u_tsize << PAGE_SHIFT)

#endif

#ifdef __sparc__

#       define START_STACK(u)   ((regs->u_regs[UREG_FP]) & ~(PAGE_SIZE - 1))

#else

#       define START_STACK(u)   (u.start_stack)

#endif

        fs = get_fs();

        set_fs(KERNEL_DS);

        has_dumped = 1;

        current->flags |= PF_DUMPCORE;

        strncpy(dump.u_comm, current->comm, sizeof(current->comm));

#ifndef __sparc__

        dump.u_ar0 = (void *)(((unsigned long)(&dump.regs)) - ((unsigned long)(&dump)));

#endif

        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.  */

#ifdef __sparc__

        if ((dump.u_dsize+dump.u_ssize) >

            current->rlim[RLIMIT_CORE].rlim_cur)

                dump.u_dsize = 0;

#else

        if ((dump.u_dsize+dump.u_ssize+1) * PAGE_SIZE >

            current->rlim[RLIMIT_CORE].rlim_cur)

                dump.u_dsize = 0;

#endif

/* Make sure we have enough room to write the stack and data areas. */

#ifdef __sparc__

        if ((dump.u_ssize) >

            current->rlim[RLIMIT_CORE].rlim_cur)

                dump.u_ssize = 0;

#else

        if ((dump.u_ssize+1) * PAGE_SIZE >

            current->rlim[RLIMIT_CORE].rlim_cur)

                dump.u_ssize = 0;

#endif

/* make sure we actually have a data and stack area to dump */

        set_fs(USER_DS);

#ifdef __sparc__

        if (verify_area(VERIFY_READ, (void *) START_DATA(dump), dump.u_dsize))

                dump.u_dsize = 0;

        if (verify_area(VERIFY_READ, (void *) START_STACK(dump), dump.u_ssize))

                dump.u_ssize = 0;

#else

        if (verify_area(VERIFY_READ, (void *) START_DATA(dump), dump.u_dsize << PAGE_SHIFT))

                dump.u_dsize = 0;

        if (verify_area(VERIFY_READ, (void *) START_STACK(dump), dump.u_ssize << PAGE_SHIFT))

                dump.u_ssize = 0;

#endif

        set_fs(KERNEL_DS);

/* struct user */

        DUMP_WRITE(&dump,sizeof(dump));

/* Now dump all of the user data.  Include malloced stuff as well */

#ifndef __sparc__

        DUMP_SEEK(PAGE_SIZE);

#endif

/* 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);

#ifdef __sparc__

                dump_size = dump.u_dsize;

#else

                dump_size = dump.u_dsize << PAGE_SHIFT;

#endif

                DUMP_WRITE(dump_start,dump_size);

        }

/* Now prepare to dump the stack area */

        if (dump.u_ssize != 0) {

                dump_start = START_STACK(dump);

#ifdef __sparc__

                dump_size = dump.u_ssize;

#else

                dump_size = dump.u_ssize << PAGE_SHIFT;

#endif

                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_aout_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 unsigned long * create_aout_tables(char * p, struct linux_binprm * bprm)

{

        char **argv, **envp;

        unsigned long * sp;

        int argc = bprm->argc;

        int envc = bprm->envc;

        sp = (unsigned long *) ((-(unsigned long)sizeof(char *)) & (unsigned long) p);

#ifdef __sparc__

        /* This imposes the proper stack alignment for a new process. */

        sp = (unsigned long *) (((unsigned long) sp) & ~7);

        if ((envc+argc+3)&1) --sp;

#endif

#ifdef __alpha__

/* whee.. test-programs are so much fun. */

        put_user(0, --sp);

        put_user(0, --sp);

        if (bprm->loader) {

                put_user(0, --sp);

                put_user(0x3eb, --sp);

                put_user(bprm->loader, --sp);

                put_user(0x3ea, --sp);

        }

        put_user(bprm->exec, --sp);

        put_user(0x3e9, --sp);

#endif

        sp -= envc+1;

        envp = (char **) sp;

        sp -= argc+1;

        argv = (char **) sp;

#if defined(__i386__) || defined(__mc68000__) || defined(__arm__) || defined(__arch_um__)

        put_user((unsigned long) envp,--sp);

        put_user((unsigned long) argv,--sp);

#endif

        put_user(argc,--sp);

        current->mm->arg_start = (unsigned long) p;

        while (argc-->0) {

                char c;

                put_user(p,argv++);

                do {

                        get_user(c,p++);

                } while (c);

        }

        put_user(NULL,argv);

        current->mm->arg_end = current->mm->env_start = (unsigned long) p;

        while (envc-->0) {

                char c;

                put_user(p,envp++);

                do {

                        get_user(c,p++);

                } while (c);

        }

        put_user(NULL,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_aout_binary(struct linux_binprm * bprm, struct pt_regs * regs)

{

        struct exec ex;

        unsigned long error;

        unsigned long fd_offset;

        unsigned long rlim;

        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_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->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 */

#if defined(__alpha__)

        SET_AOUT_PERSONALITY(bprm, ex);

#elif defined(__sparc__)

        set_personality(PER_SUNOS);

#if !defined(__sparc_v9__)

        memcpy(&current->thread.core_exec, &ex, sizeof(struct exec));

#endif

#else

        set_personality(PER_LINUX);

#endif

        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->rss = 0;

        current->mm->mmap = NULL;

        compute_creds(bprm);

        current->flags &= ~PF_FORKNOEXEC;

#ifdef __sparc__

        if (N_MAGIC(ex) == NMAGIC) {

                loff_t pos = fd_offset;

                /* Fuck me plenty... */

                /* <AOL></AOL> */

                error = do_brk(N_TXTADDR(ex), ex.a_text);

                bprm->file->f_op->read(bprm->file, (char *) N_TXTADDR(ex),

                          ex.a_text, &pos);

                error = do_brk(N_DATADDR(ex), ex.a_data);

                bprm->file->f_op->read(bprm->file, (char *) N_DATADDR(ex),

                          ex.a_data, &pos);

                goto beyond_if;

        }

#endif

        if (N_MAGIC(ex) == OMAGIC) {

                unsigned long text_addr, map_size;

                loff_t pos;

                text_addr = N_TXTADDR(ex);

#if defined(__alpha__) || defined(__sparc__)

                pos = fd_offset;

                map_size = ex.a_text+ex.a_data + PAGE_SIZE - 1;

#else

                pos = 32;

                map_size = ex.a_text+ex.a_data;

#endif

                error = do_brk(text_addr & PAGE_MASK, map_size);

                if (error != (text_addr & PAGE_MASK)) {

                        send_sig(SIGKILL, current, 0);

                        return error;

                }

                error = bprm->file->f_op->read(bprm->file, (char *)text_addr,

                          ex.a_text+ex.a_data, &pos);

                if ((signed long)error < 0) {

                        send_sig(SIGKILL, current, 0);

                        return error;

                }

                flush_icache_range(text_addr, text_addr+ex.a_text+ex.a_data);

        } else {

                static unsigned long error_time, error_time2;

                if ((ex.a_text & 0xfff || ex.a_data & 0xfff) &&

                    (N_MAGIC(ex) != NMAGIC) && (jiffies-error_time2) > 5*HZ)

                {

                        printk(KERN_NOTICE "executable not page aligned\n");

                        error_time2 = jiffies;

                }

                if ((fd_offset & ~PAGE_MASK) != 0 &&

                    (jiffies-error_time) > 5*HZ)

                {

                        printk(KERN_WARNING

                               "fd_offset is not page aligned. Please convert program: %s\n",

                               bprm->file->f_dentry->d_name.name);

                        error_time = jiffies;

                }

                if (!bprm->file->f_op->mmap||((fd_offset & ~PAGE_MASK) != 0)) {

                        loff_t pos = fd_offset;

                        do_brk(N_TXTADDR(ex), ex.a_text+ex.a_data);

                        bprm->file->f_op->read(bprm->file,(char *)N_TXTADDR(ex),

                                        ex.a_text+ex.a_data, &pos);

                        flush_icache_range((unsigned long) N_TXTADDR(ex),

                                           (unsigned long) N_TXTADDR(ex) +

                                           ex.a_text+ex.a_data);

                        goto beyond_if;

                }

                down_write(&current->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(&current->mm->mmap_sem);

                if (error != N_TXTADDR(ex)) {

                        send_sig(SIGKILL, current, 0);

                        return error;

                }

                down_write(&current->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(&current->mm->mmap_sem);

                if (error != N_DATADDR(ex)) {

                        send_sig(SIGKILL, current, 0);

                        return error;

                }

        }

beyond_if:

        set_binfmt(&aout_format);

        set_brk(current->mm->start_brk, current->mm->brk);

        retval = setup_arg_pages(bprm);

        if (retval < 0) {

                /* Someone check-me: is this error path enough? */

                send_sig(SIGKILL, current, 0);

                return retval;

        }

        current->mm->start_stack =

                (unsigned long) create_aout_tables((char *) bprm->p, bprm);

#ifdef __alpha__

        regs->gp = ex.a_gpvalue;

#endif

        start_thread(regs, ex.a_entry, current->mm->start_stack);

        if (current->ptrace & PT_PTRACED)

                send_sig(SIGTRAP, current, 0);

        return 0;

}

static int load_aout_library(struct file *file)

{

        struct inode * inode;

        unsigned long bss, start_addr, len;

        unsigned long error;

        int retval;

        struct exec ex;

        inode = file->f_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_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;

        if ((N_TXTOFF(ex) & ~PAGE_MASK) != 0) {

                static unsigned long error_time;

                loff_t pos = N_TXTOFF(ex);

                if ((jiffies-error_time) > 5*HZ)

                {

                        printk(KERN_WARNING

                               "N_TXTOFF is not page aligned. Please convert library: %s\n",

                               file->f_dentry->d_name.name);

                        error_time = jiffies;

                }

                do_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);

                file->f_op->read(file, (char *)start_addr,

                        ex.a_text + ex.a_data, &pos);

                flush_icache_range((unsigned long) start_addr,

                                   (unsigned long) start_addr + ex.a_text + ex.a_data);

                retval = 0;

                goto out;

        }

        /* Now use mmap to map the library into memory. */

        down_write(&current->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(&current->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) {

                error = do_brk(start_addr + len, bss - len);

                retval = error;

                if (error != start_addr + len)

                        goto out;

        }

        retval = 0;

out:

        return retval;

}

static int __init init_aout_binfmt(void)

{

        return register_binfmt(&aout_format);

}

static void __exit exit_aout_binfmt(void)

{

        unregister_binfmt(&aout_format);

}

EXPORT_NO_SYMBOLS;

module_init(init_aout_binfmt);

module_exit(exit_aout_binfmt);

MODULE_LICENSE("GPL");