Merge tag 'y2038-cleanups-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground

Pull y2038 cleanups from Arnd Bergmann:
 "y2038 syscall implementation cleanups

  This is a series of cleanups for the y2038 work, mostly intended for
  namespace cleaning: the kernel defines the traditional time_t, timeval
  and timespec types that often lead to y2038-unsafe code. Even though
  the unsafe usage is mostly gone from the kernel, having the types and
  associated functions around means that we can still grow new users,
  and that we may be missing conversions to safe types that actually
  matter.

  There are still a number of driver specific patches needed to get the
  last users of these types removed, those have been submitted to the
  respective maintainers"

Link: https://lore.kernel.org/lkml/20191108210236.1296047-1-arnd@arndb.de/

* tag 'y2038-cleanups-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground: (26 commits)
  y2038: alarm: fix half-second cut-off
  y2038: ipc: fix x32 ABI breakage
  y2038: fix typo in powerpc vdso "LOPART"
  y2038: allow disabling time32 system calls
  y2038: itimer: change implementation to timespec64
  y2038: move itimer reset into itimer.c
  y2038: use compat_{get,set}_itimer on alpha
  y2038: itimer: compat handling to itimer.c
  y2038: time: avoid timespec usage in settimeofday()
  y2038: timerfd: Use timespec64 internally
  y2038: elfcore: Use __kernel_old_timeval for process times
  y2038: make ns_to_compat_timeval use __kernel_old_timeval
  y2038: socket: use __kernel_old_timespec instead of timespec
  y2038: socket: remove timespec reference in timestamping
  y2038: syscalls: change remaining timeval to __kernel_old_timeval
  y2038: rusage: use __kernel_old_timeval
  y2038: uapi: change __kernel_time_t to __kernel_old_time_t
  y2038: stat: avoid 'time_t' in 'struct stat'
  y2038: ipc: remove __kernel_time_t reference from headers
  y2038: vdso: powerpc: avoid timespec references
  ...

1 files changed, 15 insertions, 17 deletions

diff --git a/kernel/time/time.c b/kernel/time/time.c
index 5c54ca632d08..58e312e7380f 100644
--- a/kernel/time/time.c
+++ b/kernel/time/time.c
@@ -59,9 +59,9 @@ EXPORT_SYMBOL(sys_tz);
  * why not move it into the appropriate arch directory (for those
  * architectures that need it).
  */
-SYSCALL_DEFINE1(time, time_t __user *, tloc)
+SYSCALL_DEFINE1(time, __kernel_old_time_t __user *, tloc)
 {
-	time_t i = (time_t)ktime_get_real_seconds();
+	__kernel_old_time_t i = (__kernel_old_time_t)ktime_get_real_seconds();
 
 	if (tloc) {
 		if (put_user(i,tloc))
@@ -78,7 +78,7 @@ SYSCALL_DEFINE1(time, time_t __user *, tloc)
  * architectures that need it).
  */
 
-SYSCALL_DEFINE1(stime, time_t __user *, tptr)
+SYSCALL_DEFINE1(stime, __kernel_old_time_t __user *, tptr)
 {
 	struct timespec64 tv;
 	int err;
@@ -137,7 +137,7 @@ SYSCALL_DEFINE1(stime32, old_time32_t __user *, tptr)
 #endif /* __ARCH_WANT_SYS_TIME32 */
 #endif
 
-SYSCALL_DEFINE2(gettimeofday, struct timeval __user *, tv,
+SYSCALL_DEFINE2(gettimeofday, struct __kernel_old_timeval __user *, tv,
 		struct timezone __user *, tz)
 {
 	if (likely(tv != NULL)) {
@@ -196,22 +196,21 @@ int do_sys_settimeofday64(const struct timespec64 *tv, const struct timezone *tz
 	return 0;
 }
 
-SYSCALL_DEFINE2(settimeofday, struct timeval __user *, tv,
+SYSCALL_DEFINE2(settimeofday, struct __kernel_old_timeval __user *, tv,
 		struct timezone __user *, tz)
 {
 	struct timespec64 new_ts;
-	struct timeval user_tv;
 	struct timezone new_tz;
 
 	if (tv) {
-		if (copy_from_user(&user_tv, tv, sizeof(*tv)))
+		if (get_user(new_ts.tv_sec, &tv->tv_sec) ||
+		    get_user(new_ts.tv_nsec, &tv->tv_usec))
 			return -EFAULT;
 
-		if (!timeval_valid(&user_tv))
+		if (new_ts.tv_nsec > USEC_PER_SEC || new_ts.tv_nsec < 0)
 			return -EINVAL;
 
-		new_ts.tv_sec = user_tv.tv_sec;
-		new_ts.tv_nsec = user_tv.tv_usec * NSEC_PER_USEC;
+		new_ts.tv_nsec *= NSEC_PER_USEC;
 	}
 	if (tz) {
 		if (copy_from_user(&new_tz, tz, sizeof(*tz)))
@@ -245,18 +244,17 @@ COMPAT_SYSCALL_DEFINE2(settimeofday, struct old_timeval32 __user *, tv,
 		       struct timezone __user *, tz)
 {
 	struct timespec64 new_ts;
-	struct timeval user_tv;
 	struct timezone new_tz;
 
 	if (tv) {
-		if (compat_get_timeval(&user_tv, tv))
+		if (get_user(new_ts.tv_sec, &tv->tv_sec) ||
+		    get_user(new_ts.tv_nsec, &tv->tv_usec))
 			return -EFAULT;
 
-		if (!timeval_valid(&user_tv))
+		if (new_ts.tv_nsec > USEC_PER_SEC || new_ts.tv_nsec < 0)
 			return -EINVAL;
 
-		new_ts.tv_sec = user_tv.tv_sec;
-		new_ts.tv_nsec = user_tv.tv_usec * NSEC_PER_USEC;
+		new_ts.tv_nsec *= NSEC_PER_USEC;
 	}
 	if (tz) {
 		if (copy_from_user(&new_tz, tz, sizeof(*tz)))
@@ -267,7 +265,7 @@ COMPAT_SYSCALL_DEFINE2(settimeofday, struct old_timeval32 __user *, tv,
 }
 #endif
 
-#if !defined(CONFIG_64BIT_TIME) || defined(CONFIG_64BIT)
+#ifdef CONFIG_64BIT
 SYSCALL_DEFINE1(adjtimex, struct __kernel_timex __user *, txc_p)
 {
 	struct __kernel_timex txc;		/* Local copy of parameter */
@@ -881,7 +879,7 @@ int get_timespec64(struct timespec64 *ts,
 	ts->tv_sec = kts.tv_sec;
 
 	/* Zero out the padding for 32 bit systems or in compat mode */
-	if (IS_ENABLED(CONFIG_64BIT_TIME) && in_compat_syscall())
+	if (in_compat_syscall())
 		kts.tv_nsec &= 0xFFFFFFFFUL;
 
 	ts->tv_nsec = kts.tv_nsec;