sys_ia32.c

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/*
 * sys_ia32.c: Conversion between 32bit and 64bit native syscalls. Based on
 *             sys_sparc32
 *
 * Copyright (C) 2000       VA Linux Co
 * Copyright (C) 2000       Don Dugger <[email protected]>
 * Copyright (C) 1999       Arun Sharma <[email protected]>
 * Copyright (C) 1997,1998  Jakub Jelinek ([email protected])
 * Copyright (C) 1997       David S. Miller ([email protected])
 * Copyright (C) 2000       Hewlett-Packard Co.
 * Copyright (C) 2000       David Mosberger-Tang <[email protected]>
 * Copyright (C) 2000,2001,2002 Andi Kleen, SuSE Labs (x86-64 port)
 *
 * These routines maintain argument size conversion between 32bit and 64bit
 * environment. In 2.5 most of this should be moved to a generic directory.
 *
 * This file assumes that there is a hole at the end of user address space.
 *
 * Some of the functions are LE specific currently. These are
 * hopefully all marked.  This should be fixed.
 */

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/signal.h>
#include <linux/syscalls.h>
#include <linux/times.h>
#include <linux/utsname.h>
#include <linux/mm.h>
#include <linux/uio.h>
#include <linux/poll.h>
#include <linux/personality.h>
#include <linux/stat.h>
#include <linux/rwsem.h>
#include <linux/compat.h>
#include <linux/vfs.h>
#include <linux/ptrace.h>
#include <linux/highuid.h>
#include <linux/sysctl.h>
#include <linux/slab.h>
#include <asm/mman.h>
#include <asm/types.h>
#include <asm/uaccess.h>
#include <linux/atomic.h>
#include <asm/vgtod.h>
#include <asm/sys_ia32.h>

#define AA(__x)     ((unsigned long)(__x))


asmlinkage long sys32_truncate64(const char __user *filename,
                 unsigned long offset_low,
                 unsigned long offset_high)
{
       return sys_truncate(filename, ((loff_t) offset_high << 32) | offset_low);
}

asmlinkage long sys32_ftruncate64(unsigned int fd, unsigned long offset_low,
                  unsigned long offset_high)
{
       return sys_ftruncate(fd, ((loff_t) offset_high << 32) | offset_low);
}

/*
 * Another set for IA32/LFS -- x86_64 struct stat is different due to
 * support for 64bit inode numbers.
 */
static int cp_stat64(struct stat64 __user *ubuf, struct kstat *stat)
{
    typeof(ubuf->st_uid) uid = 0;
    typeof(ubuf->st_gid) gid = 0;
    SET_UID(uid, from_kuid_munged(current_user_ns(), stat->uid));
    SET_GID(gid, from_kgid_munged(current_user_ns(), stat->gid));
    if (!access_ok(VERIFY_WRITE, ubuf, sizeof(struct stat64)) ||
        __put_user(huge_encode_dev(stat->dev), &ubuf->st_dev) ||
        __put_user(stat->ino, &ubuf->__st_ino) ||
        __put_user(stat->ino, &ubuf->st_ino) ||
        __put_user(stat->mode, &ubuf->st_mode) ||
        __put_user(stat->nlink, &ubuf->st_nlink) ||
        __put_user(uid, &ubuf->st_uid) ||
        __put_user(gid, &ubuf->st_gid) ||
        __put_user(huge_encode_dev(stat->rdev), &ubuf->st_rdev) ||
        __put_user(stat->size, &ubuf->st_size) ||
        __put_user(stat->atime.tv_sec, &ubuf->st_atime) ||
        __put_user(stat->atime.tv_nsec, &ubuf->st_atime_nsec) ||
        __put_user(stat->mtime.tv_sec, &ubuf->st_mtime) ||
        __put_user(stat->mtime.tv_nsec, &ubuf->st_mtime_nsec) ||
        __put_user(stat->ctime.tv_sec, &ubuf->st_ctime) ||
        __put_user(stat->ctime.tv_nsec, &ubuf->st_ctime_nsec) ||
        __put_user(stat->blksize, &ubuf->st_blksize) ||
        __put_user(stat->blocks, &ubuf->st_blocks))
        return -EFAULT;
    return 0;
}

asmlinkage long sys32_stat64(const char __user *filename,
                 struct stat64 __user *statbuf)
{
    struct kstat stat;
    int ret = vfs_stat(filename, &stat);

    if (!ret)
        ret = cp_stat64(statbuf, &stat);
    return ret;
}

asmlinkage long sys32_lstat64(const char __user *filename,
                  struct stat64 __user *statbuf)
{
    struct kstat stat;
    int ret = vfs_lstat(filename, &stat);
    if (!ret)
        ret = cp_stat64(statbuf, &stat);
    return ret;
}

asmlinkage long sys32_fstat64(unsigned int fd, struct stat64 __user *statbuf)
{
    struct kstat stat;
    int ret = vfs_fstat(fd, &stat);
    if (!ret)
        ret = cp_stat64(statbuf, &stat);
    return ret;
}

asmlinkage long sys32_fstatat(unsigned int dfd, const char __user *filename,
                  struct stat64 __user *statbuf, int flag)
{
    struct kstat stat;
    int error;

    error = vfs_fstatat(dfd, filename, &stat, flag);
    if (error)
        return error;
    return cp_stat64(statbuf, &stat);
}

/*
 * Linux/i386 didn't use to be able to handle more than
 * 4 system call parameters, so these system calls used a memory
 * block for parameter passing..
 */

struct mmap_arg_struct32 {
    unsigned int addr;
    unsigned int len;
    unsigned int prot;
    unsigned int flags;
    unsigned int fd;
    unsigned int offset;
};

asmlinkage long sys32_mmap(struct mmap_arg_struct32 __user *arg)
{
    struct mmap_arg_struct32 a;

    if (copy_from_user(&a, arg, sizeof(a)))
        return -EFAULT;

    if (a.offset & ~PAGE_MASK)
        return -EINVAL;

    return sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
                   a.offset>>PAGE_SHIFT);
}

asmlinkage long sys32_mprotect(unsigned long start, size_t len,
                   unsigned long prot)
{
    return sys_mprotect(start, len, prot);
}

asmlinkage long sys32_rt_sigaction(int sig, struct sigaction32 __user *act,
                   struct sigaction32 __user *oact,
                   unsigned int sigsetsize)
{
    struct k_sigaction new_ka, old_ka;
    int ret;
    compat_sigset_t set32;

    /* XXX: Don't preclude handling different sized sigset_t's.  */
    if (sigsetsize != sizeof(compat_sigset_t))
        return -EINVAL;

    if (act) {
        compat_uptr_t handler, restorer;

        if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
            __get_user(handler, &act->sa_handler) ||
            __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
            __get_user(restorer, &act->sa_restorer) ||
            __copy_from_user(&set32, &act->sa_mask,
                     sizeof(compat_sigset_t)))
            return -EFAULT;
        new_ka.sa.sa_handler = compat_ptr(handler);
        new_ka.sa.sa_restorer = compat_ptr(restorer);

        /*
         * FIXME: here we rely on _COMPAT_NSIG_WORS to be >=
         * than _NSIG_WORDS << 1
         */
        switch (_NSIG_WORDS) {
        case 4: new_ka.sa.sa_mask.sig[3] = set32.sig[6]
                | (((long)set32.sig[7]) << 32);
        case 3: new_ka.sa.sa_mask.sig[2] = set32.sig[4]
                | (((long)set32.sig[5]) << 32);
        case 2: new_ka.sa.sa_mask.sig[1] = set32.sig[2]
                | (((long)set32.sig[3]) << 32);
        case 1: new_ka.sa.sa_mask.sig[0] = set32.sig[0]
                | (((long)set32.sig[1]) << 32);
        }
    }

    ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);

    if (!ret && oact) {
        /*
         * FIXME: here we rely on _COMPAT_NSIG_WORS to be >=
         * than _NSIG_WORDS << 1
         */
        switch (_NSIG_WORDS) {
        case 4:
            set32.sig[7] = (old_ka.sa.sa_mask.sig[3] >> 32);
            set32.sig[6] = old_ka.sa.sa_mask.sig[3];
        case 3:
            set32.sig[5] = (old_ka.sa.sa_mask.sig[2] >> 32);
            set32.sig[4] = old_ka.sa.sa_mask.sig[2];
        case 2:
            set32.sig[3] = (old_ka.sa.sa_mask.sig[1] >> 32);
            set32.sig[2] = old_ka.sa.sa_mask.sig[1];
        case 1:
            set32.sig[1] = (old_ka.sa.sa_mask.sig[0] >> 32);
            set32.sig[0] = old_ka.sa.sa_mask.sig[0];
        }
        if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
            __put_user(ptr_to_compat(old_ka.sa.sa_handler),
                   &oact->sa_handler) ||
            __put_user(ptr_to_compat(old_ka.sa.sa_restorer),
                   &oact->sa_restorer) ||
            __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
            __copy_to_user(&oact->sa_mask, &set32,
                   sizeof(compat_sigset_t)))
            return -EFAULT;
    }

    return ret;
}

asmlinkage long sys32_sigaction(int sig, struct old_sigaction32 __user *act,
                struct old_sigaction32 __user *oact)
{
    struct k_sigaction new_ka, old_ka;
    int ret;

    if (act) {
        compat_old_sigset_t mask;
        compat_uptr_t handler, restorer;

        if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
            __get_user(handler, &act->sa_handler) ||
            __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
            __get_user(restorer, &act->sa_restorer) ||
            __get_user(mask, &act->sa_mask))
            return -EFAULT;

        new_ka.sa.sa_handler = compat_ptr(handler);
        new_ka.sa.sa_restorer = compat_ptr(restorer);

        siginitset(&new_ka.sa.sa_mask, mask);
    }

    ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);

    if (!ret && oact) {
        if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
            __put_user(ptr_to_compat(old_ka.sa.sa_handler),
                   &oact->sa_handler) ||
            __put_user(ptr_to_compat(old_ka.sa.sa_restorer),
                   &oact->sa_restorer) ||
            __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
            __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
            return -EFAULT;
    }

    return ret;
}

asmlinkage long sys32_waitpid(compat_pid_t pid, unsigned int __user *stat_addr,
                  int options)
{
    return compat_sys_wait4(pid, stat_addr, options, NULL);
}

/* 32-bit timeval and related flotsam.  */

asmlinkage long sys32_sched_rr_get_interval(compat_pid_t pid,
                    struct compat_timespec __user *interval)
{
    struct timespec t;
    int ret;
    mm_segment_t old_fs = get_fs();

    set_fs(KERNEL_DS);
    ret = sys_sched_rr_get_interval(pid, (struct timespec __user *)&t);
    set_fs(old_fs);
    if (put_compat_timespec(&t, interval))
        return -EFAULT;
    return ret;
}

asmlinkage long sys32_rt_sigpending(compat_sigset_t __user *set,
                    compat_size_t sigsetsize)
{
    sigset_t s;
    compat_sigset_t s32;
    int ret;
    mm_segment_t old_fs = get_fs();

    set_fs(KERNEL_DS);
    ret = sys_rt_sigpending((sigset_t __user *)&s, sigsetsize);
    set_fs(old_fs);
    if (!ret) {
        switch (_NSIG_WORDS) {
        case 4: s32.sig[7] = (s.sig[3] >> 32); s32.sig[6] = s.sig[3];
        case 3: s32.sig[5] = (s.sig[2] >> 32); s32.sig[4] = s.sig[2];
        case 2: s32.sig[3] = (s.sig[1] >> 32); s32.sig[2] = s.sig[1];
        case 1: s32.sig[1] = (s.sig[0] >> 32); s32.sig[0] = s.sig[0];
        }
        if (copy_to_user(set, &s32, sizeof(compat_sigset_t)))
            return -EFAULT;
    }
    return ret;
}

asmlinkage long sys32_rt_sigqueueinfo(int pid, int sig,
                      compat_siginfo_t __user *uinfo)
{
    siginfo_t info;
    int ret;
    mm_segment_t old_fs = get_fs();

    if (copy_siginfo_from_user32(&info, uinfo))
        return -EFAULT;
    set_fs(KERNEL_DS);
    ret = sys_rt_sigqueueinfo(pid, sig, (siginfo_t __user *)&info);
    set_fs(old_fs);
    return ret;
}

/* warning: next two assume little endian */
asmlinkage long sys32_pread(unsigned int fd, char __user *ubuf, u32 count,
                u32 poslo, u32 poshi)
{
    return sys_pread64(fd, ubuf, count,
             ((loff_t)AA(poshi) << 32) | AA(poslo));
}

asmlinkage long sys32_pwrite(unsigned int fd, const char __user *ubuf,
                 u32 count, u32 poslo, u32 poshi)
{
    return sys_pwrite64(fd, ubuf, count,
              ((loff_t)AA(poshi) << 32) | AA(poslo));
}


asmlinkage long sys32_sendfile(int out_fd, int in_fd,
                   compat_off_t __user *offset, s32 count)
{
    mm_segment_t old_fs = get_fs();
    int ret;
    off_t of;

    if (offset && get_user(of, offset))
        return -EFAULT;

    set_fs(KERNEL_DS);
    ret = sys_sendfile(out_fd, in_fd, offset ? (off_t __user *)&of : NULL,
               count);
    set_fs(old_fs);

    if (offset && put_user(of, offset))
        return -EFAULT;
    return ret;
}

asmlinkage long sys32_clone(unsigned int clone_flags, unsigned int newsp,
                struct pt_regs *regs)
{
    void __user *parent_tid = (void __user *)regs->dx;
    void __user *child_tid = (void __user *)regs->di;

    if (!newsp)
        newsp = regs->sp;
    return do_fork(clone_flags, newsp, regs, 0, parent_tid, child_tid);
}

/*
 * Some system calls that need sign extended arguments. This could be
 * done by a generic wrapper.
 */
long sys32_lseek(unsigned int fd, int offset, unsigned int whence)
{
    return sys_lseek(fd, offset, whence);
}

long sys32_kill(int pid, int sig)
{
    return sys_kill(pid, sig);
}

long sys32_fadvise64_64(int fd, __u32 offset_low, __u32 offset_high,
            __u32 len_low, __u32 len_high, int advice)
{
    return sys_fadvise64_64(fd,
                   (((u64)offset_high)<<32) | offset_low,
                   (((u64)len_high)<<32) | len_low,
                advice);
}

long sys32_vm86_warning(void)
{
    struct task_struct *me = current;
    static char lastcomm[sizeof(me->comm)];

    if (strncmp(lastcomm, me->comm, sizeof(lastcomm))) {
        compat_printk(KERN_INFO
                  "%s: vm86 mode not supported on 64 bit kernel\n",
                  me->comm);
        strncpy(lastcomm, me->comm, sizeof(lastcomm));
    }
    return -ENOSYS;
}

long sys32_lookup_dcookie(u32 addr_low, u32 addr_high,
              char __user *buf, size_t len)
{
    return sys_lookup_dcookie(((u64)addr_high << 32) | addr_low, buf, len);
}

asmlinkage ssize_t sys32_readahead(int fd, unsigned off_lo, unsigned off_hi,
                   size_t count)
{
    return sys_readahead(fd, ((u64)off_hi << 32) | off_lo, count);
}

asmlinkage long sys32_sync_file_range(int fd, unsigned off_low, unsigned off_hi,
                      unsigned n_low, unsigned n_hi,  int flags)
{
    return sys_sync_file_range(fd,
                   ((u64)off_hi << 32) | off_low,
                   ((u64)n_hi << 32) | n_low, flags);
}

asmlinkage long sys32_fadvise64(int fd, unsigned offset_lo, unsigned offset_hi,
                size_t len, int advice)
{
    return sys_fadvise64_64(fd, ((u64)offset_hi << 32) | offset_lo,
                len, advice);
}

asmlinkage long sys32_fallocate(int fd, int mode, unsigned offset_lo,
                unsigned offset_hi, unsigned len_lo,
                unsigned len_hi)
{
    return sys_fallocate(fd, mode, ((u64)offset_hi << 32) | offset_lo,
                 ((u64)len_hi << 32) | len_lo);
}

asmlinkage long sys32_fanotify_mark(int fanotify_fd, unsigned int flags,
                    u32 mask_lo, u32 mask_hi,
                    int fd, const char  __user *pathname)
{
    return sys_fanotify_mark(fanotify_fd, flags,
                 ((u64)mask_hi << 32) | mask_lo,
                 fd, pathname);
}