compat: Get rid of (get|put)_compat_time(val|spec)

We have two APIs for compatiblity timespec/val, with confusingly
similar names.  compat_(get|put)_time(val|spec) *do* handle the case
where COMPAT_USE_64BIT_TIME is set, whereas
(get|put)_compat_time(val|spec) do not.  This is an accident waiting
to happen.

Clean it up by favoring the full-service version; the limited version
is replaced with double-underscore versions static to kernel/compat.c.

A common pattern is to convert a struct timespec to kernel format in
an allocation on the user stack.  Unfortunately it is open-coded in
several places.  Since this allocation isn't actually needed if
COMPAT_USE_64BIT_TIME is true (since user format == kernel format)
encapsulate that whole pattern into the function
compat_convert_timespec().  An equivalent function should be written
for struct timeval if it is needed in the future.

Finally, get rid of compat_(get|put)_timeval_convert(): each was only
used once, and the latter was not even doing what the function said
(no conversion actually was being done.)  Moving the conversion into
compat_sys_settimeofday() itself makes the code much more similar to
sys_settimeofday() itself.

v3: Remove unused compat_convert_timeval().

v2: Drop bogus "const" in the destination argument for
    compat_convert_time*().

Cc: Mauro Carvalho Chehab <m.chehab@samsung.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Hans Verkuil <hans.verkuil@cisco.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Mateusz Guzik <mguzik@redhat.com>
Cc: Rafael Aquini <aquini@redhat.com>
Cc: Davidlohr Bueso <davidlohr@hp.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Tested-by: H.J. Lu <hjl.tools@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
This commit is contained in:
H. Peter Anvin 2014-02-01 18:54:11 -08:00
parent 5cb480f6b4
commit 81993e81a9
7 changed files with 75 additions and 97 deletions

View File

@ -733,7 +733,7 @@ static int put_v4l2_event32(struct v4l2_event *kp, struct v4l2_event32 __user *u
copy_to_user(&up->u, &kp->u, sizeof(kp->u)) ||
put_user(kp->pending, &up->pending) ||
put_user(kp->sequence, &up->sequence) ||
put_compat_timespec(&kp->timestamp, &up->timestamp) ||
compat_put_timespec(&kp->timestamp, &up->timestamp) ||
put_user(kp->id, &up->id) ||
copy_to_user(up->reserved, kp->reserved, 8 * sizeof(__u32)))
return -EFAULT;

View File

@ -92,8 +92,8 @@ asmlinkage long compat_sys_utimensat(unsigned int dfd, const char __user *filena
struct timespec tv[2];
if (t) {
if (get_compat_timespec(&tv[0], &t[0]) ||
get_compat_timespec(&tv[1], &t[1]))
if (compat_get_timespec(&tv[0], &t[0]) ||
compat_get_timespec(&tv[1], &t[1]))
return -EFAULT;
if (tv[0].tv_nsec == UTIME_OMIT && tv[1].tv_nsec == UTIME_OMIT)
@ -512,7 +512,7 @@ compat_sys_io_getevents(aio_context_t ctx_id,
nr * sizeof(struct io_event))))
goto out;
if (timeout) {
if (get_compat_timespec(&t, timeout))
if (compat_get_timespec(&t, timeout))
goto out;
ut = compat_alloc_user_space(sizeof(*ut));

View File

@ -140,27 +140,24 @@ struct compat_sigaction {
compat_sigset_t sa_mask __packed;
};
/*
* These functions operate strictly on struct compat_time*
*/
extern int get_compat_timespec(struct timespec *,
const struct compat_timespec __user *);
extern int put_compat_timespec(const struct timespec *,
struct compat_timespec __user *);
extern int get_compat_timeval(struct timeval *,
const struct compat_timeval __user *);
extern int put_compat_timeval(const struct timeval *,
struct compat_timeval __user *);
/*
* These functions operate on 32- or 64-bit specs depending on
* COMPAT_USE_64BIT_TIME, hence the void user pointer arguments and the
* naming as compat_get/put_ rather than get/put_compat_.
* COMPAT_USE_64BIT_TIME, hence the void user pointer arguments.
*/
extern int compat_get_timespec(struct timespec *, const void __user *);
extern int compat_put_timespec(const struct timespec *, void __user *);
extern int compat_get_timeval(struct timeval *, const void __user *);
extern int compat_put_timeval(const struct timeval *, void __user *);
/*
* This function convert a timespec if necessary and returns a *user
* space* pointer. If no conversion is necessary, it returns the
* initial pointer. NULL is a legitimate argument and will always
* output NULL.
*/
extern int compat_convert_timespec(struct timespec __user **,
const void __user *);
struct compat_iovec {
compat_uptr_t iov_base;
compat_size_t iov_len;

View File

@ -752,14 +752,8 @@ long compat_sys_shmctl(int first, int second, void __user *uptr)
long compat_sys_semtimedop(int semid, struct sembuf __user *tsems,
unsigned nsops, const struct compat_timespec __user *timeout)
{
struct timespec __user *ts64 = NULL;
if (timeout) {
struct timespec ts;
ts64 = compat_alloc_user_space(sizeof(*ts64));
if (get_compat_timespec(&ts, timeout))
return -EFAULT;
if (copy_to_user(ts64, &ts, sizeof(ts)))
return -EFAULT;
}
struct timespec __user *ts64;
if (compat_convert_timespec(&ts64, timeout))
return -EFAULT;
return sys_semtimedop(semid, tsems, nsops, ts64);
}

View File

@ -64,20 +64,6 @@ asmlinkage long compat_sys_mq_open(const char __user *u_name,
return sys_mq_open(u_name, oflag, mode, p);
}
static int compat_prepare_timeout(struct timespec __user **p,
const struct compat_timespec __user *u)
{
struct timespec ts;
if (!u) {
*p = NULL;
return 0;
}
*p = compat_alloc_user_space(sizeof(ts));
if (get_compat_timespec(&ts, u) || copy_to_user(*p, &ts, sizeof(ts)))
return -EFAULT;
return 0;
}
asmlinkage long compat_sys_mq_timedsend(mqd_t mqdes,
const char __user *u_msg_ptr,
size_t msg_len, unsigned int msg_prio,
@ -85,7 +71,7 @@ asmlinkage long compat_sys_mq_timedsend(mqd_t mqdes,
{
struct timespec __user *u_ts;
if (compat_prepare_timeout(&u_ts, u_abs_timeout))
if (compat_convert_timespec(&u_ts, u_abs_timeout))
return -EFAULT;
return sys_mq_timedsend(mqdes, u_msg_ptr, msg_len,
@ -98,7 +84,8 @@ asmlinkage ssize_t compat_sys_mq_timedreceive(mqd_t mqdes,
const struct compat_timespec __user *u_abs_timeout)
{
struct timespec __user *u_ts;
if (compat_prepare_timeout(&u_ts, u_abs_timeout))
if (compat_convert_timespec(&u_ts, u_abs_timeout))
return -EFAULT;
return sys_mq_timedreceive(mqdes, u_msg_ptr, msg_len,

View File

@ -30,28 +30,6 @@
#include <asm/uaccess.h>
/*
* Get/set struct timeval with struct timespec on the native side
*/
static int compat_get_timeval_convert(struct timespec *o,
struct compat_timeval __user *i)
{
long usec;
if (get_user(o->tv_sec, &i->tv_sec) ||
get_user(usec, &i->tv_usec))
return -EFAULT;
o->tv_nsec = usec * 1000;
return 0;
}
static int compat_put_timeval_convert(struct compat_timeval __user *o,
struct timeval *i)
{
return (put_user(i->tv_sec, &o->tv_sec) ||
put_user(i->tv_usec, &o->tv_usec)) ? -EFAULT : 0;
}
static int compat_get_timex(struct timex *txc, struct compat_timex __user *utp)
{
memset(txc, 0, sizeof(struct timex));
@ -116,7 +94,7 @@ asmlinkage long compat_sys_gettimeofday(struct compat_timeval __user *tv,
if (tv) {
struct timeval ktv;
do_gettimeofday(&ktv);
if (compat_put_timeval_convert(tv, &ktv))
if (compat_put_timeval(&ktv, tv))
return -EFAULT;
}
if (tz) {
@ -130,59 +108,58 @@ asmlinkage long compat_sys_gettimeofday(struct compat_timeval __user *tv,
asmlinkage long compat_sys_settimeofday(struct compat_timeval __user *tv,
struct timezone __user *tz)
{
struct timespec kts;
struct timezone ktz;
struct timeval user_tv;
struct timespec new_ts;
struct timezone new_tz;
if (tv) {
if (compat_get_timeval_convert(&kts, tv))
if (compat_get_timeval(&user_tv, tv))
return -EFAULT;
new_ts.tv_sec = user_tv.tv_sec;
new_ts.tv_nsec = user_tv.tv_usec * NSEC_PER_USEC;
}
if (tz) {
if (copy_from_user(&ktz, tz, sizeof(ktz)))
if (copy_from_user(&new_tz, tz, sizeof(*tz)))
return -EFAULT;
}
return do_sys_settimeofday(tv ? &kts : NULL, tz ? &ktz : NULL);
return do_sys_settimeofday(tv ? &new_ts : NULL, tz ? &new_tz : NULL);
}
int get_compat_timeval(struct timeval *tv, const struct compat_timeval __user *ctv)
static int __compat_get_timeval(struct timeval *tv, const struct compat_timeval __user *ctv)
{
return (!access_ok(VERIFY_READ, ctv, sizeof(*ctv)) ||
__get_user(tv->tv_sec, &ctv->tv_sec) ||
__get_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0;
}
EXPORT_SYMBOL_GPL(get_compat_timeval);
int put_compat_timeval(const struct timeval *tv, struct compat_timeval __user *ctv)
static int __compat_put_timeval(const struct timeval *tv, struct compat_timeval __user *ctv)
{
return (!access_ok(VERIFY_WRITE, ctv, sizeof(*ctv)) ||
__put_user(tv->tv_sec, &ctv->tv_sec) ||
__put_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0;
}
EXPORT_SYMBOL_GPL(put_compat_timeval);
int get_compat_timespec(struct timespec *ts, const struct compat_timespec __user *cts)
static int __compat_get_timespec(struct timespec *ts, const struct compat_timespec __user *cts)
{
return (!access_ok(VERIFY_READ, cts, sizeof(*cts)) ||
__get_user(ts->tv_sec, &cts->tv_sec) ||
__get_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
}
EXPORT_SYMBOL_GPL(get_compat_timespec);
int put_compat_timespec(const struct timespec *ts, struct compat_timespec __user *cts)
static int __compat_put_timespec(const struct timespec *ts, struct compat_timespec __user *cts)
{
return (!access_ok(VERIFY_WRITE, cts, sizeof(*cts)) ||
__put_user(ts->tv_sec, &cts->tv_sec) ||
__put_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
}
EXPORT_SYMBOL_GPL(put_compat_timespec);
int compat_get_timeval(struct timeval *tv, const void __user *utv)
{
if (COMPAT_USE_64BIT_TIME)
return copy_from_user(tv, utv, sizeof *tv) ? -EFAULT : 0;
else
return get_compat_timeval(tv, utv);
return __compat_get_timeval(tv, utv);
}
EXPORT_SYMBOL_GPL(compat_get_timeval);
@ -191,7 +168,7 @@ int compat_put_timeval(const struct timeval *tv, void __user *utv)
if (COMPAT_USE_64BIT_TIME)
return copy_to_user(utv, tv, sizeof *tv) ? -EFAULT : 0;
else
return put_compat_timeval(tv, utv);
return __compat_put_timeval(tv, utv);
}
EXPORT_SYMBOL_GPL(compat_put_timeval);
@ -200,7 +177,7 @@ int compat_get_timespec(struct timespec *ts, const void __user *uts)
if (COMPAT_USE_64BIT_TIME)
return copy_from_user(ts, uts, sizeof *ts) ? -EFAULT : 0;
else
return get_compat_timespec(ts, uts);
return __compat_get_timespec(ts, uts);
}
EXPORT_SYMBOL_GPL(compat_get_timespec);
@ -209,10 +186,33 @@ int compat_put_timespec(const struct timespec *ts, void __user *uts)
if (COMPAT_USE_64BIT_TIME)
return copy_to_user(uts, ts, sizeof *ts) ? -EFAULT : 0;
else
return put_compat_timespec(ts, uts);
return __compat_put_timespec(ts, uts);
}
EXPORT_SYMBOL_GPL(compat_put_timespec);
int compat_convert_timespec(struct timespec __user **kts,
const void __user *cts)
{
struct timespec ts;
struct timespec __user *uts;
if (!cts || COMPAT_USE_64BIT_TIME) {
*kts = (struct timespec __user *)cts;
return 0;
}
uts = compat_alloc_user_space(sizeof(ts));
if (!uts)
return -EFAULT;
if (compat_get_timespec(&ts, cts))
return -EFAULT;
if (copy_to_user(uts, &ts, sizeof(ts)))
return -EFAULT;
*kts = uts;
return 0;
}
static long compat_nanosleep_restart(struct restart_block *restart)
{
struct compat_timespec __user *rmtp;
@ -229,7 +229,7 @@ static long compat_nanosleep_restart(struct restart_block *restart)
if (ret) {
rmtp = restart->nanosleep.compat_rmtp;
if (rmtp && put_compat_timespec(&rmt, rmtp))
if (rmtp && compat_put_timespec(&rmt, rmtp))
return -EFAULT;
}
@ -243,7 +243,7 @@ asmlinkage long compat_sys_nanosleep(struct compat_timespec __user *rqtp,
mm_segment_t oldfs;
long ret;
if (get_compat_timespec(&tu, rqtp))
if (compat_get_timespec(&tu, rqtp))
return -EFAULT;
if (!timespec_valid(&tu))
@ -263,7 +263,7 @@ asmlinkage long compat_sys_nanosleep(struct compat_timespec __user *rqtp,
restart->fn = compat_nanosleep_restart;
restart->nanosleep.compat_rmtp = rmtp;
if (rmtp && put_compat_timespec(&rmt, rmtp))
if (rmtp && compat_put_timespec(&rmt, rmtp))
return -EFAULT;
}
@ -647,8 +647,8 @@ asmlinkage long compat_sys_sched_getaffinity(compat_pid_t pid, unsigned int len,
int get_compat_itimerspec(struct itimerspec *dst,
const struct compat_itimerspec __user *src)
{
if (get_compat_timespec(&dst->it_interval, &src->it_interval) ||
get_compat_timespec(&dst->it_value, &src->it_value))
if (__compat_get_timespec(&dst->it_interval, &src->it_interval) ||
__compat_get_timespec(&dst->it_value, &src->it_value))
return -EFAULT;
return 0;
}
@ -656,8 +656,8 @@ int get_compat_itimerspec(struct itimerspec *dst,
int put_compat_itimerspec(struct compat_itimerspec __user *dst,
const struct itimerspec *src)
{
if (put_compat_timespec(&src->it_interval, &dst->it_interval) ||
put_compat_timespec(&src->it_value, &dst->it_value))
if (__compat_put_timespec(&src->it_interval, &dst->it_interval) ||
__compat_put_timespec(&src->it_value, &dst->it_value))
return -EFAULT;
return 0;
}
@ -727,7 +727,7 @@ long compat_sys_clock_settime(clockid_t which_clock,
mm_segment_t oldfs;
struct timespec ts;
if (get_compat_timespec(&ts, tp))
if (compat_get_timespec(&ts, tp))
return -EFAULT;
oldfs = get_fs();
set_fs(KERNEL_DS);
@ -749,7 +749,7 @@ long compat_sys_clock_gettime(clockid_t which_clock,
err = sys_clock_gettime(which_clock,
(struct timespec __user *) &ts);
set_fs(oldfs);
if (!err && put_compat_timespec(&ts, tp))
if (!err && compat_put_timespec(&ts, tp))
return -EFAULT;
return err;
}
@ -789,7 +789,7 @@ long compat_sys_clock_getres(clockid_t which_clock,
err = sys_clock_getres(which_clock,
(struct timespec __user *) &ts);
set_fs(oldfs);
if (!err && tp && put_compat_timespec(&ts, tp))
if (!err && tp && compat_put_timespec(&ts, tp))
return -EFAULT;
return err;
}
@ -808,7 +808,7 @@ static long compat_clock_nanosleep_restart(struct restart_block *restart)
set_fs(oldfs);
if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
put_compat_timespec(&tu, rmtp))
compat_put_timespec(&tu, rmtp))
return -EFAULT;
if (err == -ERESTART_RESTARTBLOCK) {
@ -827,7 +827,7 @@ long compat_sys_clock_nanosleep(clockid_t which_clock, int flags,
struct timespec in, out;
struct restart_block *restart;
if (get_compat_timespec(&in, rqtp))
if (compat_get_timespec(&in, rqtp))
return -EFAULT;
oldfs = get_fs();
@ -838,7 +838,7 @@ long compat_sys_clock_nanosleep(clockid_t which_clock, int flags,
set_fs(oldfs);
if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
put_compat_timespec(&out, rmtp))
compat_put_timespec(&out, rmtp))
return -EFAULT;
if (err == -ERESTART_RESTARTBLOCK) {
@ -1130,7 +1130,7 @@ COMPAT_SYSCALL_DEFINE2(sched_rr_get_interval,
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))
if (compat_put_timespec(&t, interval))
return -EFAULT;
return ret;
}

View File

@ -183,7 +183,7 @@ COMPAT_SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val,
if (utime && (cmd == FUTEX_WAIT || cmd == FUTEX_LOCK_PI ||
cmd == FUTEX_WAIT_BITSET ||
cmd == FUTEX_WAIT_REQUEUE_PI)) {
if (get_compat_timespec(&ts, utime))
if (compat_get_timespec(&ts, utime))
return -EFAULT;
if (!timespec_valid(&ts))
return -EINVAL;