linux-stable/arch/x86/kernel/sys_ia32.c
Christian Brauner c723523bf3
x86: switch to kernel_clone()
The old _do_fork() helper is removed in favor of the new kernel_clone() helper.
The latter adheres to naming conventions for kernel internal syscall helpers.

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: x86@kernel.org
Link: https://lore.kernel.org/r/20200819104655.436656-8-christian.brauner@ubuntu.com
2020-08-20 13:12:58 +02:00

256 lines
7.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* 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 <n0ano@valinux.com>
* Copyright (C) 1999 Arun Sharma <arun.sharma@intel.com>
* Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
* Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
* Copyright (C) 2000 Hewlett-Packard Co.
* Copyright (C) 2000 David Mosberger-Tang <davidm@hpl.hp.com>
* 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 <linux/sched/task.h>
#include <asm/mman.h>
#include <asm/types.h>
#include <linux/uaccess.h>
#include <linux/atomic.h>
#include <asm/vgtod.h>
#include <asm/ia32.h>
#define AA(__x) ((unsigned long)(__x))
SYSCALL_DEFINE3(ia32_truncate64, const char __user *, filename,
unsigned long, offset_low, unsigned long, offset_high)
{
return ksys_truncate(filename,
((loff_t) offset_high << 32) | offset_low);
}
SYSCALL_DEFINE3(ia32_ftruncate64, unsigned int, fd,
unsigned long, offset_low, unsigned long, offset_high)
{
return ksys_ftruncate(fd, ((loff_t) offset_high << 32) | offset_low);
}
/* warning: next two assume little endian */
SYSCALL_DEFINE5(ia32_pread64, unsigned int, fd, char __user *, ubuf,
u32, count, u32, poslo, u32, poshi)
{
return ksys_pread64(fd, ubuf, count,
((loff_t)AA(poshi) << 32) | AA(poslo));
}
SYSCALL_DEFINE5(ia32_pwrite64, unsigned int, fd, const char __user *, ubuf,
u32, count, u32, poslo, u32, poshi)
{
return ksys_pwrite64(fd, ubuf, count,
((loff_t)AA(poshi) << 32) | AA(poslo));
}
/*
* Some system calls that need sign extended arguments. This could be
* done by a generic wrapper.
*/
SYSCALL_DEFINE6(ia32_fadvise64_64, int, fd, __u32, offset_low,
__u32, offset_high, __u32, len_low, __u32, len_high,
int, advice)
{
return ksys_fadvise64_64(fd,
(((u64)offset_high)<<32) | offset_low,
(((u64)len_high)<<32) | len_low,
advice);
}
SYSCALL_DEFINE4(ia32_readahead, int, fd, unsigned int, off_lo,
unsigned int, off_hi, size_t, count)
{
return ksys_readahead(fd, ((u64)off_hi << 32) | off_lo, count);
}
SYSCALL_DEFINE6(ia32_sync_file_range, int, fd, unsigned int, off_low,
unsigned int, off_hi, unsigned int, n_low,
unsigned int, n_hi, int, flags)
{
return ksys_sync_file_range(fd,
((u64)off_hi << 32) | off_low,
((u64)n_hi << 32) | n_low, flags);
}
SYSCALL_DEFINE5(ia32_fadvise64, int, fd, unsigned int, offset_lo,
unsigned int, offset_hi, size_t, len, int, advice)
{
return ksys_fadvise64_64(fd, ((u64)offset_hi << 32) | offset_lo,
len, advice);
}
SYSCALL_DEFINE6(ia32_fallocate, int, fd, int, mode,
unsigned int, offset_lo, unsigned int, offset_hi,
unsigned int, len_lo, unsigned int, len_hi)
{
return ksys_fallocate(fd, mode, ((u64)offset_hi << 32) | offset_lo,
((u64)len_hi << 32) | len_lo);
}
#ifdef CONFIG_IA32_EMULATION
/*
* 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 (!user_write_access_begin(ubuf, sizeof(struct stat64)))
return -EFAULT;
unsafe_put_user(huge_encode_dev(stat->dev), &ubuf->st_dev, Efault);
unsafe_put_user(stat->ino, &ubuf->__st_ino, Efault);
unsafe_put_user(stat->ino, &ubuf->st_ino, Efault);
unsafe_put_user(stat->mode, &ubuf->st_mode, Efault);
unsafe_put_user(stat->nlink, &ubuf->st_nlink, Efault);
unsafe_put_user(uid, &ubuf->st_uid, Efault);
unsafe_put_user(gid, &ubuf->st_gid, Efault);
unsafe_put_user(huge_encode_dev(stat->rdev), &ubuf->st_rdev, Efault);
unsafe_put_user(stat->size, &ubuf->st_size, Efault);
unsafe_put_user(stat->atime.tv_sec, &ubuf->st_atime, Efault);
unsafe_put_user(stat->atime.tv_nsec, &ubuf->st_atime_nsec, Efault);
unsafe_put_user(stat->mtime.tv_sec, &ubuf->st_mtime, Efault);
unsafe_put_user(stat->mtime.tv_nsec, &ubuf->st_mtime_nsec, Efault);
unsafe_put_user(stat->ctime.tv_sec, &ubuf->st_ctime, Efault);
unsafe_put_user(stat->ctime.tv_nsec, &ubuf->st_ctime_nsec, Efault);
unsafe_put_user(stat->blksize, &ubuf->st_blksize, Efault);
unsafe_put_user(stat->blocks, &ubuf->st_blocks, Efault);
user_access_end();
return 0;
Efault:
user_write_access_end();
return -EFAULT;
}
COMPAT_SYSCALL_DEFINE2(ia32_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;
}
COMPAT_SYSCALL_DEFINE2(ia32_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;
}
COMPAT_SYSCALL_DEFINE2(ia32_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;
}
COMPAT_SYSCALL_DEFINE4(ia32_fstatat64, 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;
};
COMPAT_SYSCALL_DEFINE1(ia32_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 ksys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
a.offset>>PAGE_SHIFT);
}
/*
* The 32-bit clone ABI is CONFIG_CLONE_BACKWARDS
*/
COMPAT_SYSCALL_DEFINE5(ia32_clone, unsigned long, clone_flags,
unsigned long, newsp, int __user *, parent_tidptr,
unsigned long, tls_val, int __user *, child_tidptr)
{
struct kernel_clone_args args = {
.flags = (clone_flags & ~CSIGNAL),
.pidfd = parent_tidptr,
.child_tid = child_tidptr,
.parent_tid = parent_tidptr,
.exit_signal = (clone_flags & CSIGNAL),
.stack = newsp,
.tls = tls_val,
};
return kernel_clone(&args);
}
#endif /* CONFIG_IA32_EMULATION */