1
0
mirror of https://github.com/torvalds/linux.git synced 2024-12-14 23:25:54 +00:00
linux/fs/compat.c
David Howells a6f76f23d2 CRED: Make execve() take advantage of copy-on-write credentials
Make execve() take advantage of copy-on-write credentials, allowing it to set
up the credentials in advance, and then commit the whole lot after the point
of no return.

This patch and the preceding patches have been tested with the LTP SELinux
testsuite.

This patch makes several logical sets of alteration:

 (1) execve().

     The credential bits from struct linux_binprm are, for the most part,
     replaced with a single credentials pointer (bprm->cred).  This means that
     all the creds can be calculated in advance and then applied at the point
     of no return with no possibility of failure.

     I would like to replace bprm->cap_effective with:

	cap_isclear(bprm->cap_effective)

     but this seems impossible due to special behaviour for processes of pid 1
     (they always retain their parent's capability masks where normally they'd
     be changed - see cap_bprm_set_creds()).

     The following sequence of events now happens:

     (a) At the start of do_execve, the current task's cred_exec_mutex is
     	 locked to prevent PTRACE_ATTACH from obsoleting the calculation of
     	 creds that we make.

     (a) prepare_exec_creds() is then called to make a copy of the current
     	 task's credentials and prepare it.  This copy is then assigned to
     	 bprm->cred.

  	 This renders security_bprm_alloc() and security_bprm_free()
     	 unnecessary, and so they've been removed.

     (b) The determination of unsafe execution is now performed immediately
     	 after (a) rather than later on in the code.  The result is stored in
     	 bprm->unsafe for future reference.

     (c) prepare_binprm() is called, possibly multiple times.

     	 (i) This applies the result of set[ug]id binaries to the new creds
     	     attached to bprm->cred.  Personality bit clearance is recorded,
     	     but now deferred on the basis that the exec procedure may yet
     	     fail.

         (ii) This then calls the new security_bprm_set_creds().  This should
	     calculate the new LSM and capability credentials into *bprm->cred.

	     This folds together security_bprm_set() and parts of
	     security_bprm_apply_creds() (these two have been removed).
	     Anything that might fail must be done at this point.

         (iii) bprm->cred_prepared is set to 1.

	     bprm->cred_prepared is 0 on the first pass of the security
	     calculations, and 1 on all subsequent passes.  This allows SELinux
	     in (ii) to base its calculations only on the initial script and
	     not on the interpreter.

     (d) flush_old_exec() is called to commit the task to execution.  This
     	 performs the following steps with regard to credentials:

	 (i) Clear pdeath_signal and set dumpable on certain circumstances that
	     may not be covered by commit_creds().

         (ii) Clear any bits in current->personality that were deferred from
             (c.i).

     (e) install_exec_creds() [compute_creds() as was] is called to install the
     	 new credentials.  This performs the following steps with regard to
     	 credentials:

         (i) Calls security_bprm_committing_creds() to apply any security
             requirements, such as flushing unauthorised files in SELinux, that
             must be done before the credentials are changed.

	     This is made up of bits of security_bprm_apply_creds() and
	     security_bprm_post_apply_creds(), both of which have been removed.
	     This function is not allowed to fail; anything that might fail
	     must have been done in (c.ii).

         (ii) Calls commit_creds() to apply the new credentials in a single
             assignment (more or less).  Possibly pdeath_signal and dumpable
             should be part of struct creds.

	 (iii) Unlocks the task's cred_replace_mutex, thus allowing
	     PTRACE_ATTACH to take place.

         (iv) Clears The bprm->cred pointer as the credentials it was holding
             are now immutable.

         (v) Calls security_bprm_committed_creds() to apply any security
             alterations that must be done after the creds have been changed.
             SELinux uses this to flush signals and signal handlers.

     (f) If an error occurs before (d.i), bprm_free() will call abort_creds()
     	 to destroy the proposed new credentials and will then unlock
     	 cred_replace_mutex.  No changes to the credentials will have been
     	 made.

 (2) LSM interface.

     A number of functions have been changed, added or removed:

     (*) security_bprm_alloc(), ->bprm_alloc_security()
     (*) security_bprm_free(), ->bprm_free_security()

     	 Removed in favour of preparing new credentials and modifying those.

     (*) security_bprm_apply_creds(), ->bprm_apply_creds()
     (*) security_bprm_post_apply_creds(), ->bprm_post_apply_creds()

     	 Removed; split between security_bprm_set_creds(),
     	 security_bprm_committing_creds() and security_bprm_committed_creds().

     (*) security_bprm_set(), ->bprm_set_security()

     	 Removed; folded into security_bprm_set_creds().

     (*) security_bprm_set_creds(), ->bprm_set_creds()

     	 New.  The new credentials in bprm->creds should be checked and set up
     	 as appropriate.  bprm->cred_prepared is 0 on the first call, 1 on the
     	 second and subsequent calls.

     (*) security_bprm_committing_creds(), ->bprm_committing_creds()
     (*) security_bprm_committed_creds(), ->bprm_committed_creds()

     	 New.  Apply the security effects of the new credentials.  This
     	 includes closing unauthorised files in SELinux.  This function may not
     	 fail.  When the former is called, the creds haven't yet been applied
     	 to the process; when the latter is called, they have.

 	 The former may access bprm->cred, the latter may not.

 (3) SELinux.

     SELinux has a number of changes, in addition to those to support the LSM
     interface changes mentioned above:

     (a) The bprm_security_struct struct has been removed in favour of using
     	 the credentials-under-construction approach.

     (c) flush_unauthorized_files() now takes a cred pointer and passes it on
     	 to inode_has_perm(), file_has_perm() and dentry_open().

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-11-14 10:39:24 +11:00

2201 lines
53 KiB
C

/*
* linux/fs/compat.c
*
* Kernel compatibililty routines for e.g. 32 bit syscall support
* on 64 bit kernels.
*
* Copyright (C) 2002 Stephen Rothwell, IBM Corporation
* Copyright (C) 1997-2000 Jakub Jelinek (jakub@redhat.com)
* Copyright (C) 1998 Eddie C. Dost (ecd@skynet.be)
* Copyright (C) 2001,2002 Andi Kleen, SuSE Labs
* Copyright (C) 2003 Pavel Machek (pavel@suse.cz)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/linkage.h>
#include <linux/compat.h>
#include <linux/errno.h>
#include <linux/time.h>
#include <linux/fs.h>
#include <linux/fcntl.h>
#include <linux/namei.h>
#include <linux/file.h>
#include <linux/fdtable.h>
#include <linux/vfs.h>
#include <linux/ioctl.h>
#include <linux/init.h>
#include <linux/smb.h>
#include <linux/smb_mount.h>
#include <linux/ncp_mount.h>
#include <linux/nfs4_mount.h>
#include <linux/smp_lock.h>
#include <linux/syscalls.h>
#include <linux/ctype.h>
#include <linux/module.h>
#include <linux/dirent.h>
#include <linux/fsnotify.h>
#include <linux/highuid.h>
#include <linux/sunrpc/svc.h>
#include <linux/nfsd/nfsd.h>
#include <linux/nfsd/syscall.h>
#include <linux/personality.h>
#include <linux/rwsem.h>
#include <linux/tsacct_kern.h>
#include <linux/security.h>
#include <linux/highmem.h>
#include <linux/signal.h>
#include <linux/poll.h>
#include <linux/mm.h>
#include <linux/eventpoll.h>
#include <asm/uaccess.h>
#include <asm/mmu_context.h>
#include <asm/ioctls.h>
#include "internal.h"
int compat_log = 1;
int compat_printk(const char *fmt, ...)
{
va_list ap;
int ret;
if (!compat_log)
return 0;
va_start(ap, fmt);
ret = vprintk(fmt, ap);
va_end(ap);
return ret;
}
#include "read_write.h"
/*
* Not all architectures have sys_utime, so implement this in terms
* of sys_utimes.
*/
asmlinkage long compat_sys_utime(char __user *filename, struct compat_utimbuf __user *t)
{
struct timespec tv[2];
if (t) {
if (get_user(tv[0].tv_sec, &t->actime) ||
get_user(tv[1].tv_sec, &t->modtime))
return -EFAULT;
tv[0].tv_nsec = 0;
tv[1].tv_nsec = 0;
}
return do_utimes(AT_FDCWD, filename, t ? tv : NULL, 0);
}
asmlinkage long compat_sys_utimensat(unsigned int dfd, char __user *filename, struct compat_timespec __user *t, int flags)
{
struct timespec tv[2];
if (t) {
if (get_compat_timespec(&tv[0], &t[0]) ||
get_compat_timespec(&tv[1], &t[1]))
return -EFAULT;
if ((tv[0].tv_nsec == UTIME_OMIT || tv[0].tv_nsec == UTIME_NOW)
&& tv[0].tv_sec != 0)
return -EINVAL;
if ((tv[1].tv_nsec == UTIME_OMIT || tv[1].tv_nsec == UTIME_NOW)
&& tv[1].tv_sec != 0)
return -EINVAL;
if (tv[0].tv_nsec == UTIME_OMIT && tv[1].tv_nsec == UTIME_OMIT)
return 0;
}
return do_utimes(dfd, filename, t ? tv : NULL, flags);
}
asmlinkage long compat_sys_futimesat(unsigned int dfd, char __user *filename, struct compat_timeval __user *t)
{
struct timespec tv[2];
if (t) {
if (get_user(tv[0].tv_sec, &t[0].tv_sec) ||
get_user(tv[0].tv_nsec, &t[0].tv_usec) ||
get_user(tv[1].tv_sec, &t[1].tv_sec) ||
get_user(tv[1].tv_nsec, &t[1].tv_usec))
return -EFAULT;
if (tv[0].tv_nsec >= 1000000 || tv[0].tv_nsec < 0 ||
tv[1].tv_nsec >= 1000000 || tv[1].tv_nsec < 0)
return -EINVAL;
tv[0].tv_nsec *= 1000;
tv[1].tv_nsec *= 1000;
}
return do_utimes(dfd, filename, t ? tv : NULL, 0);
}
asmlinkage long compat_sys_utimes(char __user *filename, struct compat_timeval __user *t)
{
return compat_sys_futimesat(AT_FDCWD, filename, t);
}
static int cp_compat_stat(struct kstat *stat, struct compat_stat __user *ubuf)
{
compat_ino_t ino = stat->ino;
typeof(ubuf->st_uid) uid = 0;
typeof(ubuf->st_gid) gid = 0;
int err;
SET_UID(uid, stat->uid);
SET_GID(gid, stat->gid);
if ((u64) stat->size > MAX_NON_LFS ||
!old_valid_dev(stat->dev) ||
!old_valid_dev(stat->rdev))
return -EOVERFLOW;
if (sizeof(ino) < sizeof(stat->ino) && ino != stat->ino)
return -EOVERFLOW;
if (clear_user(ubuf, sizeof(*ubuf)))
return -EFAULT;
err = __put_user(old_encode_dev(stat->dev), &ubuf->st_dev);
err |= __put_user(ino, &ubuf->st_ino);
err |= __put_user(stat->mode, &ubuf->st_mode);
err |= __put_user(stat->nlink, &ubuf->st_nlink);
err |= __put_user(uid, &ubuf->st_uid);
err |= __put_user(gid, &ubuf->st_gid);
err |= __put_user(old_encode_dev(stat->rdev), &ubuf->st_rdev);
err |= __put_user(stat->size, &ubuf->st_size);
err |= __put_user(stat->atime.tv_sec, &ubuf->st_atime);
err |= __put_user(stat->atime.tv_nsec, &ubuf->st_atime_nsec);
err |= __put_user(stat->mtime.tv_sec, &ubuf->st_mtime);
err |= __put_user(stat->mtime.tv_nsec, &ubuf->st_mtime_nsec);
err |= __put_user(stat->ctime.tv_sec, &ubuf->st_ctime);
err |= __put_user(stat->ctime.tv_nsec, &ubuf->st_ctime_nsec);
err |= __put_user(stat->blksize, &ubuf->st_blksize);
err |= __put_user(stat->blocks, &ubuf->st_blocks);
return err;
}
asmlinkage long compat_sys_newstat(char __user * filename,
struct compat_stat __user *statbuf)
{
struct kstat stat;
int error = vfs_stat_fd(AT_FDCWD, filename, &stat);
if (!error)
error = cp_compat_stat(&stat, statbuf);
return error;
}
asmlinkage long compat_sys_newlstat(char __user * filename,
struct compat_stat __user *statbuf)
{
struct kstat stat;
int error = vfs_lstat_fd(AT_FDCWD, filename, &stat);
if (!error)
error = cp_compat_stat(&stat, statbuf);
return error;
}
#ifndef __ARCH_WANT_STAT64
asmlinkage long compat_sys_newfstatat(unsigned int dfd, char __user *filename,
struct compat_stat __user *statbuf, int flag)
{
struct kstat stat;
int error = -EINVAL;
if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0)
goto out;
if (flag & AT_SYMLINK_NOFOLLOW)
error = vfs_lstat_fd(dfd, filename, &stat);
else
error = vfs_stat_fd(dfd, filename, &stat);
if (!error)
error = cp_compat_stat(&stat, statbuf);
out:
return error;
}
#endif
asmlinkage long compat_sys_newfstat(unsigned int fd,
struct compat_stat __user * statbuf)
{
struct kstat stat;
int error = vfs_fstat(fd, &stat);
if (!error)
error = cp_compat_stat(&stat, statbuf);
return error;
}
static int put_compat_statfs(struct compat_statfs __user *ubuf, struct kstatfs *kbuf)
{
if (sizeof ubuf->f_blocks == 4) {
if ((kbuf->f_blocks | kbuf->f_bfree | kbuf->f_bavail |
kbuf->f_bsize | kbuf->f_frsize) & 0xffffffff00000000ULL)
return -EOVERFLOW;
/* f_files and f_ffree may be -1; it's okay
* to stuff that into 32 bits */
if (kbuf->f_files != 0xffffffffffffffffULL
&& (kbuf->f_files & 0xffffffff00000000ULL))
return -EOVERFLOW;
if (kbuf->f_ffree != 0xffffffffffffffffULL
&& (kbuf->f_ffree & 0xffffffff00000000ULL))
return -EOVERFLOW;
}
if (!access_ok(VERIFY_WRITE, ubuf, sizeof(*ubuf)) ||
__put_user(kbuf->f_type, &ubuf->f_type) ||
__put_user(kbuf->f_bsize, &ubuf->f_bsize) ||
__put_user(kbuf->f_blocks, &ubuf->f_blocks) ||
__put_user(kbuf->f_bfree, &ubuf->f_bfree) ||
__put_user(kbuf->f_bavail, &ubuf->f_bavail) ||
__put_user(kbuf->f_files, &ubuf->f_files) ||
__put_user(kbuf->f_ffree, &ubuf->f_ffree) ||
__put_user(kbuf->f_namelen, &ubuf->f_namelen) ||
__put_user(kbuf->f_fsid.val[0], &ubuf->f_fsid.val[0]) ||
__put_user(kbuf->f_fsid.val[1], &ubuf->f_fsid.val[1]) ||
__put_user(kbuf->f_frsize, &ubuf->f_frsize) ||
__put_user(0, &ubuf->f_spare[0]) ||
__put_user(0, &ubuf->f_spare[1]) ||
__put_user(0, &ubuf->f_spare[2]) ||
__put_user(0, &ubuf->f_spare[3]) ||
__put_user(0, &ubuf->f_spare[4]))
return -EFAULT;
return 0;
}
/*
* The following statfs calls are copies of code from fs/open.c and
* should be checked against those from time to time
*/
asmlinkage long compat_sys_statfs(const char __user *pathname, struct compat_statfs __user *buf)
{
struct path path;
int error;
error = user_path(pathname, &path);
if (!error) {
struct kstatfs tmp;
error = vfs_statfs(path.dentry, &tmp);
if (!error)
error = put_compat_statfs(buf, &tmp);
path_put(&path);
}
return error;
}
asmlinkage long compat_sys_fstatfs(unsigned int fd, struct compat_statfs __user *buf)
{
struct file * file;
struct kstatfs tmp;
int error;
error = -EBADF;
file = fget(fd);
if (!file)
goto out;
error = vfs_statfs(file->f_path.dentry, &tmp);
if (!error)
error = put_compat_statfs(buf, &tmp);
fput(file);
out:
return error;
}
static int put_compat_statfs64(struct compat_statfs64 __user *ubuf, struct kstatfs *kbuf)
{
if (sizeof ubuf->f_blocks == 4) {
if ((kbuf->f_blocks | kbuf->f_bfree | kbuf->f_bavail |
kbuf->f_bsize | kbuf->f_frsize) & 0xffffffff00000000ULL)
return -EOVERFLOW;
/* f_files and f_ffree may be -1; it's okay
* to stuff that into 32 bits */
if (kbuf->f_files != 0xffffffffffffffffULL
&& (kbuf->f_files & 0xffffffff00000000ULL))
return -EOVERFLOW;
if (kbuf->f_ffree != 0xffffffffffffffffULL
&& (kbuf->f_ffree & 0xffffffff00000000ULL))
return -EOVERFLOW;
}
if (!access_ok(VERIFY_WRITE, ubuf, sizeof(*ubuf)) ||
__put_user(kbuf->f_type, &ubuf->f_type) ||
__put_user(kbuf->f_bsize, &ubuf->f_bsize) ||
__put_user(kbuf->f_blocks, &ubuf->f_blocks) ||
__put_user(kbuf->f_bfree, &ubuf->f_bfree) ||
__put_user(kbuf->f_bavail, &ubuf->f_bavail) ||
__put_user(kbuf->f_files, &ubuf->f_files) ||
__put_user(kbuf->f_ffree, &ubuf->f_ffree) ||
__put_user(kbuf->f_namelen, &ubuf->f_namelen) ||
__put_user(kbuf->f_fsid.val[0], &ubuf->f_fsid.val[0]) ||
__put_user(kbuf->f_fsid.val[1], &ubuf->f_fsid.val[1]) ||
__put_user(kbuf->f_frsize, &ubuf->f_frsize))
return -EFAULT;
return 0;
}
asmlinkage long compat_sys_statfs64(const char __user *pathname, compat_size_t sz, struct compat_statfs64 __user *buf)
{
struct path path;
int error;
if (sz != sizeof(*buf))
return -EINVAL;
error = user_path(pathname, &path);
if (!error) {
struct kstatfs tmp;
error = vfs_statfs(path.dentry, &tmp);
if (!error)
error = put_compat_statfs64(buf, &tmp);
path_put(&path);
}
return error;
}
asmlinkage long compat_sys_fstatfs64(unsigned int fd, compat_size_t sz, struct compat_statfs64 __user *buf)
{
struct file * file;
struct kstatfs tmp;
int error;
if (sz != sizeof(*buf))
return -EINVAL;
error = -EBADF;
file = fget(fd);
if (!file)
goto out;
error = vfs_statfs(file->f_path.dentry, &tmp);
if (!error)
error = put_compat_statfs64(buf, &tmp);
fput(file);
out:
return error;
}
static int get_compat_flock(struct flock *kfl, struct compat_flock __user *ufl)
{
if (!access_ok(VERIFY_READ, ufl, sizeof(*ufl)) ||
__get_user(kfl->l_type, &ufl->l_type) ||
__get_user(kfl->l_whence, &ufl->l_whence) ||
__get_user(kfl->l_start, &ufl->l_start) ||
__get_user(kfl->l_len, &ufl->l_len) ||
__get_user(kfl->l_pid, &ufl->l_pid))
return -EFAULT;
return 0;
}
static int put_compat_flock(struct flock *kfl, struct compat_flock __user *ufl)
{
if (!access_ok(VERIFY_WRITE, ufl, sizeof(*ufl)) ||
__put_user(kfl->l_type, &ufl->l_type) ||
__put_user(kfl->l_whence, &ufl->l_whence) ||
__put_user(kfl->l_start, &ufl->l_start) ||
__put_user(kfl->l_len, &ufl->l_len) ||
__put_user(kfl->l_pid, &ufl->l_pid))
return -EFAULT;
return 0;
}
#ifndef HAVE_ARCH_GET_COMPAT_FLOCK64
static int get_compat_flock64(struct flock *kfl, struct compat_flock64 __user *ufl)
{
if (!access_ok(VERIFY_READ, ufl, sizeof(*ufl)) ||
__get_user(kfl->l_type, &ufl->l_type) ||
__get_user(kfl->l_whence, &ufl->l_whence) ||
__get_user(kfl->l_start, &ufl->l_start) ||
__get_user(kfl->l_len, &ufl->l_len) ||
__get_user(kfl->l_pid, &ufl->l_pid))
return -EFAULT;
return 0;
}
#endif
#ifndef HAVE_ARCH_PUT_COMPAT_FLOCK64
static int put_compat_flock64(struct flock *kfl, struct compat_flock64 __user *ufl)
{
if (!access_ok(VERIFY_WRITE, ufl, sizeof(*ufl)) ||
__put_user(kfl->l_type, &ufl->l_type) ||
__put_user(kfl->l_whence, &ufl->l_whence) ||
__put_user(kfl->l_start, &ufl->l_start) ||
__put_user(kfl->l_len, &ufl->l_len) ||
__put_user(kfl->l_pid, &ufl->l_pid))
return -EFAULT;
return 0;
}
#endif
asmlinkage long compat_sys_fcntl64(unsigned int fd, unsigned int cmd,
unsigned long arg)
{
mm_segment_t old_fs;
struct flock f;
long ret;
switch (cmd) {
case F_GETLK:
case F_SETLK:
case F_SETLKW:
ret = get_compat_flock(&f, compat_ptr(arg));
if (ret != 0)
break;
old_fs = get_fs();
set_fs(KERNEL_DS);
ret = sys_fcntl(fd, cmd, (unsigned long)&f);
set_fs(old_fs);
if (cmd == F_GETLK && ret == 0) {
/* GETLK was successfule and we need to return the data...
* but it needs to fit in the compat structure.
* l_start shouldn't be too big, unless the original
* start + end is greater than COMPAT_OFF_T_MAX, in which
* case the app was asking for trouble, so we return
* -EOVERFLOW in that case.
* l_len could be too big, in which case we just truncate it,
* and only allow the app to see that part of the conflicting
* lock that might make sense to it anyway
*/
if (f.l_start > COMPAT_OFF_T_MAX)
ret = -EOVERFLOW;
if (f.l_len > COMPAT_OFF_T_MAX)
f.l_len = COMPAT_OFF_T_MAX;
if (ret == 0)
ret = put_compat_flock(&f, compat_ptr(arg));
}
break;
case F_GETLK64:
case F_SETLK64:
case F_SETLKW64:
ret = get_compat_flock64(&f, compat_ptr(arg));
if (ret != 0)
break;
old_fs = get_fs();
set_fs(KERNEL_DS);
ret = sys_fcntl(fd, (cmd == F_GETLK64) ? F_GETLK :
((cmd == F_SETLK64) ? F_SETLK : F_SETLKW),
(unsigned long)&f);
set_fs(old_fs);
if (cmd == F_GETLK64 && ret == 0) {
/* need to return lock information - see above for commentary */
if (f.l_start > COMPAT_LOFF_T_MAX)
ret = -EOVERFLOW;
if (f.l_len > COMPAT_LOFF_T_MAX)
f.l_len = COMPAT_LOFF_T_MAX;
if (ret == 0)
ret = put_compat_flock64(&f, compat_ptr(arg));
}
break;
default:
ret = sys_fcntl(fd, cmd, arg);
break;
}
return ret;
}
asmlinkage long compat_sys_fcntl(unsigned int fd, unsigned int cmd,
unsigned long arg)
{
if ((cmd == F_GETLK64) || (cmd == F_SETLK64) || (cmd == F_SETLKW64))
return -EINVAL;
return compat_sys_fcntl64(fd, cmd, arg);
}
asmlinkage long
compat_sys_io_setup(unsigned nr_reqs, u32 __user *ctx32p)
{
long ret;
aio_context_t ctx64;
mm_segment_t oldfs = get_fs();
if (unlikely(get_user(ctx64, ctx32p)))
return -EFAULT;
set_fs(KERNEL_DS);
/* The __user pointer cast is valid because of the set_fs() */
ret = sys_io_setup(nr_reqs, (aio_context_t __user *) &ctx64);
set_fs(oldfs);
/* truncating is ok because it's a user address */
if (!ret)
ret = put_user((u32) ctx64, ctx32p);
return ret;
}
asmlinkage long
compat_sys_io_getevents(aio_context_t ctx_id,
unsigned long min_nr,
unsigned long nr,
struct io_event __user *events,
struct compat_timespec __user *timeout)
{
long ret;
struct timespec t;
struct timespec __user *ut = NULL;
ret = -EFAULT;
if (unlikely(!access_ok(VERIFY_WRITE, events,
nr * sizeof(struct io_event))))
goto out;
if (timeout) {
if (get_compat_timespec(&t, timeout))
goto out;
ut = compat_alloc_user_space(sizeof(*ut));
if (copy_to_user(ut, &t, sizeof(t)) )
goto out;
}
ret = sys_io_getevents(ctx_id, min_nr, nr, events, ut);
out:
return ret;
}
static inline long
copy_iocb(long nr, u32 __user *ptr32, struct iocb __user * __user *ptr64)
{
compat_uptr_t uptr;
int i;
for (i = 0; i < nr; ++i) {
if (get_user(uptr, ptr32 + i))
return -EFAULT;
if (put_user(compat_ptr(uptr), ptr64 + i))
return -EFAULT;
}
return 0;
}
#define MAX_AIO_SUBMITS (PAGE_SIZE/sizeof(struct iocb *))
asmlinkage long
compat_sys_io_submit(aio_context_t ctx_id, int nr, u32 __user *iocb)
{
struct iocb __user * __user *iocb64;
long ret;
if (unlikely(nr < 0))
return -EINVAL;
if (nr > MAX_AIO_SUBMITS)
nr = MAX_AIO_SUBMITS;
iocb64 = compat_alloc_user_space(nr * sizeof(*iocb64));
ret = copy_iocb(nr, iocb, iocb64);
if (!ret)
ret = sys_io_submit(ctx_id, nr, iocb64);
return ret;
}
struct compat_ncp_mount_data {
compat_int_t version;
compat_uint_t ncp_fd;
__compat_uid_t mounted_uid;
compat_pid_t wdog_pid;
unsigned char mounted_vol[NCP_VOLNAME_LEN + 1];
compat_uint_t time_out;
compat_uint_t retry_count;
compat_uint_t flags;
__compat_uid_t uid;
__compat_gid_t gid;
compat_mode_t file_mode;
compat_mode_t dir_mode;
};
struct compat_ncp_mount_data_v4 {
compat_int_t version;
compat_ulong_t flags;
compat_ulong_t mounted_uid;
compat_long_t wdog_pid;
compat_uint_t ncp_fd;
compat_uint_t time_out;
compat_uint_t retry_count;
compat_ulong_t uid;
compat_ulong_t gid;
compat_ulong_t file_mode;
compat_ulong_t dir_mode;
};
static void *do_ncp_super_data_conv(void *raw_data)
{
int version = *(unsigned int *)raw_data;
if (version == 3) {
struct compat_ncp_mount_data *c_n = raw_data;
struct ncp_mount_data *n = raw_data;
n->dir_mode = c_n->dir_mode;
n->file_mode = c_n->file_mode;
n->gid = c_n->gid;
n->uid = c_n->uid;
memmove (n->mounted_vol, c_n->mounted_vol, (sizeof (c_n->mounted_vol) + 3 * sizeof (unsigned int)));
n->wdog_pid = c_n->wdog_pid;
n->mounted_uid = c_n->mounted_uid;
} else if (version == 4) {
struct compat_ncp_mount_data_v4 *c_n = raw_data;
struct ncp_mount_data_v4 *n = raw_data;
n->dir_mode = c_n->dir_mode;
n->file_mode = c_n->file_mode;
n->gid = c_n->gid;
n->uid = c_n->uid;
n->retry_count = c_n->retry_count;
n->time_out = c_n->time_out;
n->ncp_fd = c_n->ncp_fd;
n->wdog_pid = c_n->wdog_pid;
n->mounted_uid = c_n->mounted_uid;
n->flags = c_n->flags;
} else if (version != 5) {
return NULL;
}
return raw_data;
}
struct compat_smb_mount_data {
compat_int_t version;
__compat_uid_t mounted_uid;
__compat_uid_t uid;
__compat_gid_t gid;
compat_mode_t file_mode;
compat_mode_t dir_mode;
};
static void *do_smb_super_data_conv(void *raw_data)
{
struct smb_mount_data *s = raw_data;
struct compat_smb_mount_data *c_s = raw_data;
if (c_s->version != SMB_MOUNT_OLDVERSION)
goto out;
s->dir_mode = c_s->dir_mode;
s->file_mode = c_s->file_mode;
s->gid = c_s->gid;
s->uid = c_s->uid;
s->mounted_uid = c_s->mounted_uid;
out:
return raw_data;
}
struct compat_nfs_string {
compat_uint_t len;
compat_uptr_t data;
};
static inline void compat_nfs_string(struct nfs_string *dst,
struct compat_nfs_string *src)
{
dst->data = compat_ptr(src->data);
dst->len = src->len;
}
struct compat_nfs4_mount_data_v1 {
compat_int_t version;
compat_int_t flags;
compat_int_t rsize;
compat_int_t wsize;
compat_int_t timeo;
compat_int_t retrans;
compat_int_t acregmin;
compat_int_t acregmax;
compat_int_t acdirmin;
compat_int_t acdirmax;
struct compat_nfs_string client_addr;
struct compat_nfs_string mnt_path;
struct compat_nfs_string hostname;
compat_uint_t host_addrlen;
compat_uptr_t host_addr;
compat_int_t proto;
compat_int_t auth_flavourlen;
compat_uptr_t auth_flavours;
};
static int do_nfs4_super_data_conv(void *raw_data)
{
int version = *(compat_uint_t *) raw_data;
if (version == 1) {
struct compat_nfs4_mount_data_v1 *raw = raw_data;
struct nfs4_mount_data *real = raw_data;
/* copy the fields backwards */
real->auth_flavours = compat_ptr(raw->auth_flavours);
real->auth_flavourlen = raw->auth_flavourlen;
real->proto = raw->proto;
real->host_addr = compat_ptr(raw->host_addr);
real->host_addrlen = raw->host_addrlen;
compat_nfs_string(&real->hostname, &raw->hostname);
compat_nfs_string(&real->mnt_path, &raw->mnt_path);
compat_nfs_string(&real->client_addr, &raw->client_addr);
real->acdirmax = raw->acdirmax;
real->acdirmin = raw->acdirmin;
real->acregmax = raw->acregmax;
real->acregmin = raw->acregmin;
real->retrans = raw->retrans;
real->timeo = raw->timeo;
real->wsize = raw->wsize;
real->rsize = raw->rsize;
real->flags = raw->flags;
real->version = raw->version;
}
return 0;
}
#define SMBFS_NAME "smbfs"
#define NCPFS_NAME "ncpfs"
#define NFS4_NAME "nfs4"
asmlinkage long compat_sys_mount(char __user * dev_name, char __user * dir_name,
char __user * type, unsigned long flags,
void __user * data)
{
unsigned long type_page;
unsigned long data_page;
unsigned long dev_page;
char *dir_page;
int retval;
retval = copy_mount_options (type, &type_page);
if (retval < 0)
goto out;
dir_page = getname(dir_name);
retval = PTR_ERR(dir_page);
if (IS_ERR(dir_page))
goto out1;
retval = copy_mount_options (dev_name, &dev_page);
if (retval < 0)
goto out2;
retval = copy_mount_options (data, &data_page);
if (retval < 0)
goto out3;
retval = -EINVAL;
if (type_page && data_page) {
if (!strcmp((char *)type_page, SMBFS_NAME)) {
do_smb_super_data_conv((void *)data_page);
} else if (!strcmp((char *)type_page, NCPFS_NAME)) {
do_ncp_super_data_conv((void *)data_page);
} else if (!strcmp((char *)type_page, NFS4_NAME)) {
if (do_nfs4_super_data_conv((void *) data_page))
goto out4;
}
}
lock_kernel();
retval = do_mount((char*)dev_page, dir_page, (char*)type_page,
flags, (void*)data_page);
unlock_kernel();
out4:
free_page(data_page);
out3:
free_page(dev_page);
out2:
putname(dir_page);
out1:
free_page(type_page);
out:
return retval;
}
#define NAME_OFFSET(de) ((int) ((de)->d_name - (char __user *) (de)))
struct compat_old_linux_dirent {
compat_ulong_t d_ino;
compat_ulong_t d_offset;
unsigned short d_namlen;
char d_name[1];
};
struct compat_readdir_callback {
struct compat_old_linux_dirent __user *dirent;
int result;
};
static int compat_fillonedir(void *__buf, const char *name, int namlen,
loff_t offset, u64 ino, unsigned int d_type)
{
struct compat_readdir_callback *buf = __buf;
struct compat_old_linux_dirent __user *dirent;
compat_ulong_t d_ino;
if (buf->result)
return -EINVAL;
d_ino = ino;
if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
buf->result = -EOVERFLOW;
return -EOVERFLOW;
}
buf->result++;
dirent = buf->dirent;
if (!access_ok(VERIFY_WRITE, dirent,
(unsigned long)(dirent->d_name + namlen + 1) -
(unsigned long)dirent))
goto efault;
if ( __put_user(d_ino, &dirent->d_ino) ||
__put_user(offset, &dirent->d_offset) ||
__put_user(namlen, &dirent->d_namlen) ||
__copy_to_user(dirent->d_name, name, namlen) ||
__put_user(0, dirent->d_name + namlen))
goto efault;
return 0;
efault:
buf->result = -EFAULT;
return -EFAULT;
}
asmlinkage long compat_sys_old_readdir(unsigned int fd,
struct compat_old_linux_dirent __user *dirent, unsigned int count)
{
int error;
struct file *file;
struct compat_readdir_callback buf;
error = -EBADF;
file = fget(fd);
if (!file)
goto out;
buf.result = 0;
buf.dirent = dirent;
error = vfs_readdir(file, compat_fillonedir, &buf);
if (buf.result)
error = buf.result;
fput(file);
out:
return error;
}
struct compat_linux_dirent {
compat_ulong_t d_ino;
compat_ulong_t d_off;
unsigned short d_reclen;
char d_name[1];
};
struct compat_getdents_callback {
struct compat_linux_dirent __user *current_dir;
struct compat_linux_dirent __user *previous;
int count;
int error;
};
static int compat_filldir(void *__buf, const char *name, int namlen,
loff_t offset, u64 ino, unsigned int d_type)
{
struct compat_linux_dirent __user * dirent;
struct compat_getdents_callback *buf = __buf;
compat_ulong_t d_ino;
int reclen = ALIGN(NAME_OFFSET(dirent) + namlen + 2, sizeof(compat_long_t));
buf->error = -EINVAL; /* only used if we fail.. */
if (reclen > buf->count)
return -EINVAL;
d_ino = ino;
if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
buf->error = -EOVERFLOW;
return -EOVERFLOW;
}
dirent = buf->previous;
if (dirent) {
if (__put_user(offset, &dirent->d_off))
goto efault;
}
dirent = buf->current_dir;
if (__put_user(d_ino, &dirent->d_ino))
goto efault;
if (__put_user(reclen, &dirent->d_reclen))
goto efault;
if (copy_to_user(dirent->d_name, name, namlen))
goto efault;
if (__put_user(0, dirent->d_name + namlen))
goto efault;
if (__put_user(d_type, (char __user *) dirent + reclen - 1))
goto efault;
buf->previous = dirent;
dirent = (void __user *)dirent + reclen;
buf->current_dir = dirent;
buf->count -= reclen;
return 0;
efault:
buf->error = -EFAULT;
return -EFAULT;
}
asmlinkage long compat_sys_getdents(unsigned int fd,
struct compat_linux_dirent __user *dirent, unsigned int count)
{
struct file * file;
struct compat_linux_dirent __user * lastdirent;
struct compat_getdents_callback buf;
int error;
error = -EFAULT;
if (!access_ok(VERIFY_WRITE, dirent, count))
goto out;
error = -EBADF;
file = fget(fd);
if (!file)
goto out;
buf.current_dir = dirent;
buf.previous = NULL;
buf.count = count;
buf.error = 0;
error = vfs_readdir(file, compat_filldir, &buf);
if (error >= 0)
error = buf.error;
lastdirent = buf.previous;
if (lastdirent) {
if (put_user(file->f_pos, &lastdirent->d_off))
error = -EFAULT;
else
error = count - buf.count;
}
fput(file);
out:
return error;
}
#ifndef __ARCH_OMIT_COMPAT_SYS_GETDENTS64
struct compat_getdents_callback64 {
struct linux_dirent64 __user *current_dir;
struct linux_dirent64 __user *previous;
int count;
int error;
};
static int compat_filldir64(void * __buf, const char * name, int namlen, loff_t offset,
u64 ino, unsigned int d_type)
{
struct linux_dirent64 __user *dirent;
struct compat_getdents_callback64 *buf = __buf;
int jj = NAME_OFFSET(dirent);
int reclen = ALIGN(jj + namlen + 1, sizeof(u64));
u64 off;
buf->error = -EINVAL; /* only used if we fail.. */
if (reclen > buf->count)
return -EINVAL;
dirent = buf->previous;
if (dirent) {
if (__put_user_unaligned(offset, &dirent->d_off))
goto efault;
}
dirent = buf->current_dir;
if (__put_user_unaligned(ino, &dirent->d_ino))
goto efault;
off = 0;
if (__put_user_unaligned(off, &dirent->d_off))
goto efault;
if (__put_user(reclen, &dirent->d_reclen))
goto efault;
if (__put_user(d_type, &dirent->d_type))
goto efault;
if (copy_to_user(dirent->d_name, name, namlen))
goto efault;
if (__put_user(0, dirent->d_name + namlen))
goto efault;
buf->previous = dirent;
dirent = (void __user *)dirent + reclen;
buf->current_dir = dirent;
buf->count -= reclen;
return 0;
efault:
buf->error = -EFAULT;
return -EFAULT;
}
asmlinkage long compat_sys_getdents64(unsigned int fd,
struct linux_dirent64 __user * dirent, unsigned int count)
{
struct file * file;
struct linux_dirent64 __user * lastdirent;
struct compat_getdents_callback64 buf;
int error;
error = -EFAULT;
if (!access_ok(VERIFY_WRITE, dirent, count))
goto out;
error = -EBADF;
file = fget(fd);
if (!file)
goto out;
buf.current_dir = dirent;
buf.previous = NULL;
buf.count = count;
buf.error = 0;
error = vfs_readdir(file, compat_filldir64, &buf);
if (error >= 0)
error = buf.error;
lastdirent = buf.previous;
if (lastdirent) {
typeof(lastdirent->d_off) d_off = file->f_pos;
if (__put_user_unaligned(d_off, &lastdirent->d_off))
error = -EFAULT;
else
error = count - buf.count;
}
fput(file);
out:
return error;
}
#endif /* ! __ARCH_OMIT_COMPAT_SYS_GETDENTS64 */
static ssize_t compat_do_readv_writev(int type, struct file *file,
const struct compat_iovec __user *uvector,
unsigned long nr_segs, loff_t *pos)
{
compat_ssize_t tot_len;
struct iovec iovstack[UIO_FASTIOV];
struct iovec *iov=iovstack, *vector;
ssize_t ret;
int seg;
io_fn_t fn;
iov_fn_t fnv;
/*
* SuS says "The readv() function *may* fail if the iovcnt argument
* was less than or equal to 0, or greater than {IOV_MAX}. Linux has
* traditionally returned zero for zero segments, so...
*/
ret = 0;
if (nr_segs == 0)
goto out;
/*
* First get the "struct iovec" from user memory and
* verify all the pointers
*/
ret = -EINVAL;
if ((nr_segs > UIO_MAXIOV) || (nr_segs <= 0))
goto out;
if (!file->f_op)
goto out;
if (nr_segs > UIO_FASTIOV) {
ret = -ENOMEM;
iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL);
if (!iov)
goto out;
}
ret = -EFAULT;
if (!access_ok(VERIFY_READ, uvector, nr_segs*sizeof(*uvector)))
goto out;
/*
* Single unix specification:
* We should -EINVAL if an element length is not >= 0 and fitting an
* ssize_t. The total length is fitting an ssize_t
*
* Be careful here because iov_len is a size_t not an ssize_t
*/
tot_len = 0;
vector = iov;
ret = -EINVAL;
for (seg = 0 ; seg < nr_segs; seg++) {
compat_ssize_t tmp = tot_len;
compat_ssize_t len;
compat_uptr_t buf;
if (__get_user(len, &uvector->iov_len) ||
__get_user(buf, &uvector->iov_base)) {
ret = -EFAULT;
goto out;
}
if (len < 0) /* size_t not fitting an compat_ssize_t .. */
goto out;
tot_len += len;
if (tot_len < tmp) /* maths overflow on the compat_ssize_t */
goto out;
vector->iov_base = compat_ptr(buf);
vector->iov_len = (compat_size_t) len;
uvector++;
vector++;
}
if (tot_len == 0) {
ret = 0;
goto out;
}
ret = rw_verify_area(type, file, pos, tot_len);
if (ret < 0)
goto out;
fnv = NULL;
if (type == READ) {
fn = file->f_op->read;
fnv = file->f_op->aio_read;
} else {
fn = (io_fn_t)file->f_op->write;
fnv = file->f_op->aio_write;
}
if (fnv)
ret = do_sync_readv_writev(file, iov, nr_segs, tot_len,
pos, fnv);
else
ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn);
out:
if (iov != iovstack)
kfree(iov);
if ((ret + (type == READ)) > 0) {
struct dentry *dentry = file->f_path.dentry;
if (type == READ)
fsnotify_access(dentry);
else
fsnotify_modify(dentry);
}
return ret;
}
asmlinkage ssize_t
compat_sys_readv(unsigned long fd, const struct compat_iovec __user *vec, unsigned long vlen)
{
struct file *file;
ssize_t ret = -EBADF;
file = fget(fd);
if (!file)
return -EBADF;
if (!(file->f_mode & FMODE_READ))
goto out;
ret = -EINVAL;
if (!file->f_op || (!file->f_op->aio_read && !file->f_op->read))
goto out;
ret = compat_do_readv_writev(READ, file, vec, vlen, &file->f_pos);
out:
fput(file);
return ret;
}
asmlinkage ssize_t
compat_sys_writev(unsigned long fd, const struct compat_iovec __user *vec, unsigned long vlen)
{
struct file *file;
ssize_t ret = -EBADF;
file = fget(fd);
if (!file)
return -EBADF;
if (!(file->f_mode & FMODE_WRITE))
goto out;
ret = -EINVAL;
if (!file->f_op || (!file->f_op->aio_write && !file->f_op->write))
goto out;
ret = compat_do_readv_writev(WRITE, file, vec, vlen, &file->f_pos);
out:
fput(file);
return ret;
}
asmlinkage long
compat_sys_vmsplice(int fd, const struct compat_iovec __user *iov32,
unsigned int nr_segs, unsigned int flags)
{
unsigned i;
struct iovec __user *iov;
if (nr_segs > UIO_MAXIOV)
return -EINVAL;
iov = compat_alloc_user_space(nr_segs * sizeof(struct iovec));
for (i = 0; i < nr_segs; i++) {
struct compat_iovec v;
if (get_user(v.iov_base, &iov32[i].iov_base) ||
get_user(v.iov_len, &iov32[i].iov_len) ||
put_user(compat_ptr(v.iov_base), &iov[i].iov_base) ||
put_user(v.iov_len, &iov[i].iov_len))
return -EFAULT;
}
return sys_vmsplice(fd, iov, nr_segs, flags);
}
/*
* Exactly like fs/open.c:sys_open(), except that it doesn't set the
* O_LARGEFILE flag.
*/
asmlinkage long
compat_sys_open(const char __user *filename, int flags, int mode)
{
return do_sys_open(AT_FDCWD, filename, flags, mode);
}
/*
* Exactly like fs/open.c:sys_openat(), except that it doesn't set the
* O_LARGEFILE flag.
*/
asmlinkage long
compat_sys_openat(unsigned int dfd, const char __user *filename, int flags, int mode)
{
return do_sys_open(dfd, filename, flags, mode);
}
/*
* compat_count() counts the number of arguments/envelopes. It is basically
* a copy of count() from fs/exec.c, except that it works with 32 bit argv
* and envp pointers.
*/
static int compat_count(compat_uptr_t __user *argv, int max)
{
int i = 0;
if (argv != NULL) {
for (;;) {
compat_uptr_t p;
if (get_user(p, argv))
return -EFAULT;
if (!p)
break;
argv++;
if (i++ >= max)
return -E2BIG;
}
}
return i;
}
/*
* compat_copy_strings() is basically a copy of copy_strings() from fs/exec.c
* except that it works with 32 bit argv and envp pointers.
*/
static int compat_copy_strings(int argc, compat_uptr_t __user *argv,
struct linux_binprm *bprm)
{
struct page *kmapped_page = NULL;
char *kaddr = NULL;
unsigned long kpos = 0;
int ret;
while (argc-- > 0) {
compat_uptr_t str;
int len;
unsigned long pos;
if (get_user(str, argv+argc) ||
!(len = strnlen_user(compat_ptr(str), MAX_ARG_STRLEN))) {
ret = -EFAULT;
goto out;
}
if (len > MAX_ARG_STRLEN) {
ret = -E2BIG;
goto out;
}
/* We're going to work our way backwords. */
pos = bprm->p;
str += len;
bprm->p -= len;
while (len > 0) {
int offset, bytes_to_copy;
offset = pos % PAGE_SIZE;
if (offset == 0)
offset = PAGE_SIZE;
bytes_to_copy = offset;
if (bytes_to_copy > len)
bytes_to_copy = len;
offset -= bytes_to_copy;
pos -= bytes_to_copy;
str -= bytes_to_copy;
len -= bytes_to_copy;
if (!kmapped_page || kpos != (pos & PAGE_MASK)) {
struct page *page;
#ifdef CONFIG_STACK_GROWSUP
ret = expand_stack_downwards(bprm->vma, pos);
if (ret < 0) {
/* We've exceed the stack rlimit. */
ret = -E2BIG;
goto out;
}
#endif
ret = get_user_pages(current, bprm->mm, pos,
1, 1, 1, &page, NULL);
if (ret <= 0) {
/* We've exceed the stack rlimit. */
ret = -E2BIG;
goto out;
}
if (kmapped_page) {
flush_kernel_dcache_page(kmapped_page);
kunmap(kmapped_page);
put_page(kmapped_page);
}
kmapped_page = page;
kaddr = kmap(kmapped_page);
kpos = pos & PAGE_MASK;
flush_cache_page(bprm->vma, kpos,
page_to_pfn(kmapped_page));
}
if (copy_from_user(kaddr+offset, compat_ptr(str),
bytes_to_copy)) {
ret = -EFAULT;
goto out;
}
}
}
ret = 0;
out:
if (kmapped_page) {
flush_kernel_dcache_page(kmapped_page);
kunmap(kmapped_page);
put_page(kmapped_page);
}
return ret;
}
/*
* compat_do_execve() is mostly a copy of do_execve(), with the exception
* that it processes 32 bit argv and envp pointers.
*/
int compat_do_execve(char * filename,
compat_uptr_t __user *argv,
compat_uptr_t __user *envp,
struct pt_regs * regs)
{
struct linux_binprm *bprm;
struct file *file;
int retval;
retval = -ENOMEM;
bprm = kzalloc(sizeof(*bprm), GFP_KERNEL);
if (!bprm)
goto out_ret;
retval = mutex_lock_interruptible(&current->cred_exec_mutex);
if (retval < 0)
goto out_free;
retval = -ENOMEM;
bprm->cred = prepare_exec_creds();
if (!bprm->cred)
goto out_unlock;
check_unsafe_exec(bprm);
file = open_exec(filename);
retval = PTR_ERR(file);
if (IS_ERR(file))
goto out_unlock;
sched_exec();
bprm->file = file;
bprm->filename = filename;
bprm->interp = filename;
retval = bprm_mm_init(bprm);
if (retval)
goto out_file;
bprm->argc = compat_count(argv, MAX_ARG_STRINGS);
if ((retval = bprm->argc) < 0)
goto out;
bprm->envc = compat_count(envp, MAX_ARG_STRINGS);
if ((retval = bprm->envc) < 0)
goto out;
retval = prepare_binprm(bprm);
if (retval < 0)
goto out;
retval = copy_strings_kernel(1, &bprm->filename, bprm);
if (retval < 0)
goto out;
bprm->exec = bprm->p;
retval = compat_copy_strings(bprm->envc, envp, bprm);
if (retval < 0)
goto out;
retval = compat_copy_strings(bprm->argc, argv, bprm);
if (retval < 0)
goto out;
retval = search_binary_handler(bprm, regs);
if (retval < 0)
goto out;
/* execve succeeded */
mutex_unlock(&current->cred_exec_mutex);
acct_update_integrals(current);
free_bprm(bprm);
return retval;
out:
if (bprm->mm)
mmput(bprm->mm);
out_file:
if (bprm->file) {
allow_write_access(bprm->file);
fput(bprm->file);
}
out_unlock:
mutex_unlock(&current->cred_exec_mutex);
out_free:
free_bprm(bprm);
out_ret:
return retval;
}
#define __COMPAT_NFDBITS (8 * sizeof(compat_ulong_t))
static int poll_select_copy_remaining(struct timespec *end_time, void __user *p,
int timeval, int ret)
{
struct timespec ts;
if (!p)
return ret;
if (current->personality & STICKY_TIMEOUTS)
goto sticky;
/* No update for zero timeout */
if (!end_time->tv_sec && !end_time->tv_nsec)
return ret;
ktime_get_ts(&ts);
ts = timespec_sub(*end_time, ts);
if (ts.tv_sec < 0)
ts.tv_sec = ts.tv_nsec = 0;
if (timeval) {
struct compat_timeval rtv;
rtv.tv_sec = ts.tv_sec;
rtv.tv_usec = ts.tv_nsec / NSEC_PER_USEC;
if (!copy_to_user(p, &rtv, sizeof(rtv)))
return ret;
} else {
struct compat_timespec rts;
rts.tv_sec = ts.tv_sec;
rts.tv_nsec = ts.tv_nsec;
if (!copy_to_user(p, &rts, sizeof(rts)))
return ret;
}
/*
* If an application puts its timeval in read-only memory, we
* don't want the Linux-specific update to the timeval to
* cause a fault after the select has completed
* successfully. However, because we're not updating the
* timeval, we can't restart the system call.
*/
sticky:
if (ret == -ERESTARTNOHAND)
ret = -EINTR;
return ret;
}
/*
* Ooo, nasty. We need here to frob 32-bit unsigned longs to
* 64-bit unsigned longs.
*/
static
int compat_get_fd_set(unsigned long nr, compat_ulong_t __user *ufdset,
unsigned long *fdset)
{
nr = DIV_ROUND_UP(nr, __COMPAT_NFDBITS);
if (ufdset) {
unsigned long odd;
if (!access_ok(VERIFY_WRITE, ufdset, nr*sizeof(compat_ulong_t)))
return -EFAULT;
odd = nr & 1UL;
nr &= ~1UL;
while (nr) {
unsigned long h, l;
if (__get_user(l, ufdset) || __get_user(h, ufdset+1))
return -EFAULT;
ufdset += 2;
*fdset++ = h << 32 | l;
nr -= 2;
}
if (odd && __get_user(*fdset, ufdset))
return -EFAULT;
} else {
/* Tricky, must clear full unsigned long in the
* kernel fdset at the end, this makes sure that
* actually happens.
*/
memset(fdset, 0, ((nr + 1) & ~1)*sizeof(compat_ulong_t));
}
return 0;
}
static
int compat_set_fd_set(unsigned long nr, compat_ulong_t __user *ufdset,
unsigned long *fdset)
{
unsigned long odd;
nr = DIV_ROUND_UP(nr, __COMPAT_NFDBITS);
if (!ufdset)
return 0;
odd = nr & 1UL;
nr &= ~1UL;
while (nr) {
unsigned long h, l;
l = *fdset++;
h = l >> 32;
if (__put_user(l, ufdset) || __put_user(h, ufdset+1))
return -EFAULT;
ufdset += 2;
nr -= 2;
}
if (odd && __put_user(*fdset, ufdset))
return -EFAULT;
return 0;
}
/*
* This is a virtual copy of sys_select from fs/select.c and probably
* should be compared to it from time to time
*/
/*
* We can actually return ERESTARTSYS instead of EINTR, but I'd
* like to be certain this leads to no problems. So I return
* EINTR just for safety.
*
* Update: ERESTARTSYS breaks at least the xview clock binary, so
* I'm trying ERESTARTNOHAND which restart only when you want to.
*/
#define MAX_SELECT_SECONDS \
((unsigned long) (MAX_SCHEDULE_TIMEOUT / HZ)-1)
int compat_core_sys_select(int n, compat_ulong_t __user *inp,
compat_ulong_t __user *outp, compat_ulong_t __user *exp,
struct timespec *end_time)
{
fd_set_bits fds;
void *bits;
int size, max_fds, ret = -EINVAL;
struct fdtable *fdt;
long stack_fds[SELECT_STACK_ALLOC/sizeof(long)];
if (n < 0)
goto out_nofds;
/* max_fds can increase, so grab it once to avoid race */
rcu_read_lock();
fdt = files_fdtable(current->files);
max_fds = fdt->max_fds;
rcu_read_unlock();
if (n > max_fds)
n = max_fds;
/*
* We need 6 bitmaps (in/out/ex for both incoming and outgoing),
* since we used fdset we need to allocate memory in units of
* long-words.
*/
size = FDS_BYTES(n);
bits = stack_fds;
if (size > sizeof(stack_fds) / 6) {
bits = kmalloc(6 * size, GFP_KERNEL);
ret = -ENOMEM;
if (!bits)
goto out_nofds;
}
fds.in = (unsigned long *) bits;
fds.out = (unsigned long *) (bits + size);
fds.ex = (unsigned long *) (bits + 2*size);
fds.res_in = (unsigned long *) (bits + 3*size);
fds.res_out = (unsigned long *) (bits + 4*size);
fds.res_ex = (unsigned long *) (bits + 5*size);
if ((ret = compat_get_fd_set(n, inp, fds.in)) ||
(ret = compat_get_fd_set(n, outp, fds.out)) ||
(ret = compat_get_fd_set(n, exp, fds.ex)))
goto out;
zero_fd_set(n, fds.res_in);
zero_fd_set(n, fds.res_out);
zero_fd_set(n, fds.res_ex);
ret = do_select(n, &fds, end_time);
if (ret < 0)
goto out;
if (!ret) {
ret = -ERESTARTNOHAND;
if (signal_pending(current))
goto out;
ret = 0;
}
if (compat_set_fd_set(n, inp, fds.res_in) ||
compat_set_fd_set(n, outp, fds.res_out) ||
compat_set_fd_set(n, exp, fds.res_ex))
ret = -EFAULT;
out:
if (bits != stack_fds)
kfree(bits);
out_nofds:
return ret;
}
asmlinkage long compat_sys_select(int n, compat_ulong_t __user *inp,
compat_ulong_t __user *outp, compat_ulong_t __user *exp,
struct compat_timeval __user *tvp)
{
struct timespec end_time, *to = NULL;
struct compat_timeval tv;
int ret;
if (tvp) {
if (copy_from_user(&tv, tvp, sizeof(tv)))
return -EFAULT;
to = &end_time;
if (poll_select_set_timeout(to,
tv.tv_sec + (tv.tv_usec / USEC_PER_SEC),
(tv.tv_usec % USEC_PER_SEC) * NSEC_PER_USEC))
return -EINVAL;
}
ret = compat_core_sys_select(n, inp, outp, exp, to);
ret = poll_select_copy_remaining(&end_time, tvp, 1, ret);
return ret;
}
#ifdef HAVE_SET_RESTORE_SIGMASK
asmlinkage long compat_sys_pselect7(int n, compat_ulong_t __user *inp,
compat_ulong_t __user *outp, compat_ulong_t __user *exp,
struct compat_timespec __user *tsp, compat_sigset_t __user *sigmask,
compat_size_t sigsetsize)
{
compat_sigset_t ss32;
sigset_t ksigmask, sigsaved;
struct compat_timespec ts;
struct timespec end_time, *to = NULL;
int ret;
if (tsp) {
if (copy_from_user(&ts, tsp, sizeof(ts)))
return -EFAULT;
to = &end_time;
if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))
return -EINVAL;
}
if (sigmask) {
if (sigsetsize != sizeof(compat_sigset_t))
return -EINVAL;
if (copy_from_user(&ss32, sigmask, sizeof(ss32)))
return -EFAULT;
sigset_from_compat(&ksigmask, &ss32);
sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP));
sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
}
ret = compat_core_sys_select(n, inp, outp, exp, to);
ret = poll_select_copy_remaining(&end_time, tsp, 0, ret);
if (ret == -ERESTARTNOHAND) {
/*
* Don't restore the signal mask yet. Let do_signal() deliver
* the signal on the way back to userspace, before the signal
* mask is restored.
*/
if (sigmask) {
memcpy(&current->saved_sigmask, &sigsaved,
sizeof(sigsaved));
set_restore_sigmask();
}
} else if (sigmask)
sigprocmask(SIG_SETMASK, &sigsaved, NULL);
return ret;
}
asmlinkage long compat_sys_pselect6(int n, compat_ulong_t __user *inp,
compat_ulong_t __user *outp, compat_ulong_t __user *exp,
struct compat_timespec __user *tsp, void __user *sig)
{
compat_size_t sigsetsize = 0;
compat_uptr_t up = 0;
if (sig) {
if (!access_ok(VERIFY_READ, sig,
sizeof(compat_uptr_t)+sizeof(compat_size_t)) ||
__get_user(up, (compat_uptr_t __user *)sig) ||
__get_user(sigsetsize,
(compat_size_t __user *)(sig+sizeof(up))))
return -EFAULT;
}
return compat_sys_pselect7(n, inp, outp, exp, tsp, compat_ptr(up),
sigsetsize);
}
asmlinkage long compat_sys_ppoll(struct pollfd __user *ufds,
unsigned int nfds, struct compat_timespec __user *tsp,
const compat_sigset_t __user *sigmask, compat_size_t sigsetsize)
{
compat_sigset_t ss32;
sigset_t ksigmask, sigsaved;
struct compat_timespec ts;
struct timespec end_time, *to = NULL;
int ret;
if (tsp) {
if (copy_from_user(&ts, tsp, sizeof(ts)))
return -EFAULT;
to = &end_time;
if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))
return -EINVAL;
}
if (sigmask) {
if (sigsetsize != sizeof(compat_sigset_t))
return -EINVAL;
if (copy_from_user(&ss32, sigmask, sizeof(ss32)))
return -EFAULT;
sigset_from_compat(&ksigmask, &ss32);
sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP));
sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
}
ret = do_sys_poll(ufds, nfds, to);
/* We can restart this syscall, usually */
if (ret == -EINTR) {
/*
* Don't restore the signal mask yet. Let do_signal() deliver
* the signal on the way back to userspace, before the signal
* mask is restored.
*/
if (sigmask) {
memcpy(&current->saved_sigmask, &sigsaved,
sizeof(sigsaved));
set_restore_sigmask();
}
ret = -ERESTARTNOHAND;
} else if (sigmask)
sigprocmask(SIG_SETMASK, &sigsaved, NULL);
ret = poll_select_copy_remaining(&end_time, tsp, 0, ret);
return ret;
}
#endif /* HAVE_SET_RESTORE_SIGMASK */
#if defined(CONFIG_NFSD) || defined(CONFIG_NFSD_MODULE)
/* Stuff for NFS server syscalls... */
struct compat_nfsctl_svc {
u16 svc32_port;
s32 svc32_nthreads;
};
struct compat_nfsctl_client {
s8 cl32_ident[NFSCLNT_IDMAX+1];
s32 cl32_naddr;
struct in_addr cl32_addrlist[NFSCLNT_ADDRMAX];
s32 cl32_fhkeytype;
s32 cl32_fhkeylen;
u8 cl32_fhkey[NFSCLNT_KEYMAX];
};
struct compat_nfsctl_export {
char ex32_client[NFSCLNT_IDMAX+1];
char ex32_path[NFS_MAXPATHLEN+1];
compat_dev_t ex32_dev;
compat_ino_t ex32_ino;
compat_int_t ex32_flags;
__compat_uid_t ex32_anon_uid;
__compat_gid_t ex32_anon_gid;
};
struct compat_nfsctl_fdparm {
struct sockaddr gd32_addr;
s8 gd32_path[NFS_MAXPATHLEN+1];
compat_int_t gd32_version;
};
struct compat_nfsctl_fsparm {
struct sockaddr gd32_addr;
s8 gd32_path[NFS_MAXPATHLEN+1];
compat_int_t gd32_maxlen;
};
struct compat_nfsctl_arg {
compat_int_t ca32_version; /* safeguard */
union {
struct compat_nfsctl_svc u32_svc;
struct compat_nfsctl_client u32_client;
struct compat_nfsctl_export u32_export;
struct compat_nfsctl_fdparm u32_getfd;
struct compat_nfsctl_fsparm u32_getfs;
} u;
#define ca32_svc u.u32_svc
#define ca32_client u.u32_client
#define ca32_export u.u32_export
#define ca32_getfd u.u32_getfd
#define ca32_getfs u.u32_getfs
};
union compat_nfsctl_res {
__u8 cr32_getfh[NFS_FHSIZE];
struct knfsd_fh cr32_getfs;
};
static int compat_nfs_svc_trans(struct nfsctl_arg *karg,
struct compat_nfsctl_arg __user *arg)
{
if (!access_ok(VERIFY_READ, &arg->ca32_svc, sizeof(arg->ca32_svc)) ||
get_user(karg->ca_version, &arg->ca32_version) ||
__get_user(karg->ca_svc.svc_port, &arg->ca32_svc.svc32_port) ||
__get_user(karg->ca_svc.svc_nthreads,
&arg->ca32_svc.svc32_nthreads))
return -EFAULT;
return 0;
}
static int compat_nfs_clnt_trans(struct nfsctl_arg *karg,
struct compat_nfsctl_arg __user *arg)
{
if (!access_ok(VERIFY_READ, &arg->ca32_client,
sizeof(arg->ca32_client)) ||
get_user(karg->ca_version, &arg->ca32_version) ||
__copy_from_user(&karg->ca_client.cl_ident[0],
&arg->ca32_client.cl32_ident[0],
NFSCLNT_IDMAX) ||
__get_user(karg->ca_client.cl_naddr,
&arg->ca32_client.cl32_naddr) ||
__copy_from_user(&karg->ca_client.cl_addrlist[0],
&arg->ca32_client.cl32_addrlist[0],
(sizeof(struct in_addr) * NFSCLNT_ADDRMAX)) ||
__get_user(karg->ca_client.cl_fhkeytype,
&arg->ca32_client.cl32_fhkeytype) ||
__get_user(karg->ca_client.cl_fhkeylen,
&arg->ca32_client.cl32_fhkeylen) ||
__copy_from_user(&karg->ca_client.cl_fhkey[0],
&arg->ca32_client.cl32_fhkey[0],
NFSCLNT_KEYMAX))
return -EFAULT;
return 0;
}
static int compat_nfs_exp_trans(struct nfsctl_arg *karg,
struct compat_nfsctl_arg __user *arg)
{
if (!access_ok(VERIFY_READ, &arg->ca32_export,
sizeof(arg->ca32_export)) ||
get_user(karg->ca_version, &arg->ca32_version) ||
__copy_from_user(&karg->ca_export.ex_client[0],
&arg->ca32_export.ex32_client[0],
NFSCLNT_IDMAX) ||
__copy_from_user(&karg->ca_export.ex_path[0],
&arg->ca32_export.ex32_path[0],
NFS_MAXPATHLEN) ||
__get_user(karg->ca_export.ex_dev,
&arg->ca32_export.ex32_dev) ||
__get_user(karg->ca_export.ex_ino,
&arg->ca32_export.ex32_ino) ||
__get_user(karg->ca_export.ex_flags,
&arg->ca32_export.ex32_flags) ||
__get_user(karg->ca_export.ex_anon_uid,
&arg->ca32_export.ex32_anon_uid) ||
__get_user(karg->ca_export.ex_anon_gid,
&arg->ca32_export.ex32_anon_gid))
return -EFAULT;
SET_UID(karg->ca_export.ex_anon_uid, karg->ca_export.ex_anon_uid);
SET_GID(karg->ca_export.ex_anon_gid, karg->ca_export.ex_anon_gid);
return 0;
}
static int compat_nfs_getfd_trans(struct nfsctl_arg *karg,
struct compat_nfsctl_arg __user *arg)
{
if (!access_ok(VERIFY_READ, &arg->ca32_getfd,
sizeof(arg->ca32_getfd)) ||
get_user(karg->ca_version, &arg->ca32_version) ||
__copy_from_user(&karg->ca_getfd.gd_addr,
&arg->ca32_getfd.gd32_addr,
(sizeof(struct sockaddr))) ||
__copy_from_user(&karg->ca_getfd.gd_path,
&arg->ca32_getfd.gd32_path,
(NFS_MAXPATHLEN+1)) ||
__get_user(karg->ca_getfd.gd_version,
&arg->ca32_getfd.gd32_version))
return -EFAULT;
return 0;
}
static int compat_nfs_getfs_trans(struct nfsctl_arg *karg,
struct compat_nfsctl_arg __user *arg)
{
if (!access_ok(VERIFY_READ,&arg->ca32_getfs,sizeof(arg->ca32_getfs)) ||
get_user(karg->ca_version, &arg->ca32_version) ||
__copy_from_user(&karg->ca_getfs.gd_addr,
&arg->ca32_getfs.gd32_addr,
(sizeof(struct sockaddr))) ||
__copy_from_user(&karg->ca_getfs.gd_path,
&arg->ca32_getfs.gd32_path,
(NFS_MAXPATHLEN+1)) ||
__get_user(karg->ca_getfs.gd_maxlen,
&arg->ca32_getfs.gd32_maxlen))
return -EFAULT;
return 0;
}
/* This really doesn't need translations, we are only passing
* back a union which contains opaque nfs file handle data.
*/
static int compat_nfs_getfh_res_trans(union nfsctl_res *kres,
union compat_nfsctl_res __user *res)
{
int err;
err = copy_to_user(res, kres, sizeof(*res));
return (err) ? -EFAULT : 0;
}
asmlinkage long compat_sys_nfsservctl(int cmd,
struct compat_nfsctl_arg __user *arg,
union compat_nfsctl_res __user *res)
{
struct nfsctl_arg *karg;
union nfsctl_res *kres;
mm_segment_t oldfs;
int err;
karg = kmalloc(sizeof(*karg), GFP_USER);
kres = kmalloc(sizeof(*kres), GFP_USER);
if(!karg || !kres) {
err = -ENOMEM;
goto done;
}
switch(cmd) {
case NFSCTL_SVC:
err = compat_nfs_svc_trans(karg, arg);
break;
case NFSCTL_ADDCLIENT:
err = compat_nfs_clnt_trans(karg, arg);
break;
case NFSCTL_DELCLIENT:
err = compat_nfs_clnt_trans(karg, arg);
break;
case NFSCTL_EXPORT:
case NFSCTL_UNEXPORT:
err = compat_nfs_exp_trans(karg, arg);
break;
case NFSCTL_GETFD:
err = compat_nfs_getfd_trans(karg, arg);
break;
case NFSCTL_GETFS:
err = compat_nfs_getfs_trans(karg, arg);
break;
default:
err = -EINVAL;
break;
}
if (err)
goto done;
oldfs = get_fs();
set_fs(KERNEL_DS);
/* The __user pointer casts are valid because of the set_fs() */
err = sys_nfsservctl(cmd, (void __user *) karg, (void __user *) kres);
set_fs(oldfs);
if (err)
goto done;
if((cmd == NFSCTL_GETFD) ||
(cmd == NFSCTL_GETFS))
err = compat_nfs_getfh_res_trans(kres, res);
done:
kfree(karg);
kfree(kres);
return err;
}
#else /* !NFSD */
long asmlinkage compat_sys_nfsservctl(int cmd, void *notused, void *notused2)
{
return sys_ni_syscall();
}
#endif
#ifdef CONFIG_EPOLL
#ifdef HAVE_SET_RESTORE_SIGMASK
asmlinkage long compat_sys_epoll_pwait(int epfd,
struct compat_epoll_event __user *events,
int maxevents, int timeout,
const compat_sigset_t __user *sigmask,
compat_size_t sigsetsize)
{
long err;
compat_sigset_t csigmask;
sigset_t ksigmask, sigsaved;
/*
* If the caller wants a certain signal mask to be set during the wait,
* we apply it here.
*/
if (sigmask) {
if (sigsetsize != sizeof(compat_sigset_t))
return -EINVAL;
if (copy_from_user(&csigmask, sigmask, sizeof(csigmask)))
return -EFAULT;
sigset_from_compat(&ksigmask, &csigmask);
sigdelsetmask(&ksigmask, sigmask(SIGKILL) | sigmask(SIGSTOP));
sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
}
err = sys_epoll_wait(epfd, events, maxevents, timeout);
/*
* If we changed the signal mask, we need to restore the original one.
* In case we've got a signal while waiting, we do not restore the
* signal mask yet, and we allow do_signal() to deliver the signal on
* the way back to userspace, before the signal mask is restored.
*/
if (sigmask) {
if (err == -EINTR) {
memcpy(&current->saved_sigmask, &sigsaved,
sizeof(sigsaved));
set_restore_sigmask();
} else
sigprocmask(SIG_SETMASK, &sigsaved, NULL);
}
return err;
}
#endif /* HAVE_SET_RESTORE_SIGMASK */
#endif /* CONFIG_EPOLL */
#ifdef CONFIG_SIGNALFD
asmlinkage long compat_sys_signalfd4(int ufd,
const compat_sigset_t __user *sigmask,
compat_size_t sigsetsize, int flags)
{
compat_sigset_t ss32;
sigset_t tmp;
sigset_t __user *ksigmask;
if (sigsetsize != sizeof(compat_sigset_t))
return -EINVAL;
if (copy_from_user(&ss32, sigmask, sizeof(ss32)))
return -EFAULT;
sigset_from_compat(&tmp, &ss32);
ksigmask = compat_alloc_user_space(sizeof(sigset_t));
if (copy_to_user(ksigmask, &tmp, sizeof(sigset_t)))
return -EFAULT;
return sys_signalfd4(ufd, ksigmask, sizeof(sigset_t), flags);
}
asmlinkage long compat_sys_signalfd(int ufd,
const compat_sigset_t __user *sigmask,
compat_size_t sigsetsize)
{
return compat_sys_signalfd4(ufd, sigmask, sigsetsize, 0);
}
#endif /* CONFIG_SIGNALFD */
#ifdef CONFIG_TIMERFD
asmlinkage long compat_sys_timerfd_settime(int ufd, int flags,
const struct compat_itimerspec __user *utmr,
struct compat_itimerspec __user *otmr)
{
int error;
struct itimerspec t;
struct itimerspec __user *ut;
if (get_compat_itimerspec(&t, utmr))
return -EFAULT;
ut = compat_alloc_user_space(2 * sizeof(struct itimerspec));
if (copy_to_user(&ut[0], &t, sizeof(t)))
return -EFAULT;
error = sys_timerfd_settime(ufd, flags, &ut[0], &ut[1]);
if (!error && otmr)
error = (copy_from_user(&t, &ut[1], sizeof(struct itimerspec)) ||
put_compat_itimerspec(otmr, &t)) ? -EFAULT: 0;
return error;
}
asmlinkage long compat_sys_timerfd_gettime(int ufd,
struct compat_itimerspec __user *otmr)
{
int error;
struct itimerspec t;
struct itimerspec __user *ut;
ut = compat_alloc_user_space(sizeof(struct itimerspec));
error = sys_timerfd_gettime(ufd, ut);
if (!error)
error = (copy_from_user(&t, ut, sizeof(struct itimerspec)) ||
put_compat_itimerspec(otmr, &t)) ? -EFAULT: 0;
return error;
}
#endif /* CONFIG_TIMERFD */