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>
diff --git a/kernel/compat.c b/kernel/compat.c
index 0a09e48..3afc524 100644
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -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 @@
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_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 @@
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 @@
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 @@
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 @@
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 @@
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 @@
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 @@
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 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 @@
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 @@
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 @@
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 @@
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 @@
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 @@
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 @@
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;
}