[PATCH 17/23] y2038: time: avoid timespec usage in settimeofday()

From: Arnd Bergmann
Date: Fri Nov 08 2019 - 16:17:10 EST


The compat_get_timeval() and timeval_valid() interfaces
are deprecated and getting removed along with the definition
of struct timeval itself.

Change the two implementations of the settimeofday()
system call to open-code these helpers and completely
avoid references to timeval.

Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
include/linux/syscalls.h | 2 +-
kernel/time/time.c | 20 +++++++++-----------
2 files changed, 10 insertions(+), 12 deletions(-)

diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index e665920fa359..d0391cc2dae9 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -734,7 +734,7 @@ asmlinkage long sys_getcpu(unsigned __user *cpu, unsigned __user *node, struct g
/* kernel/time.c */
asmlinkage long sys_gettimeofday(struct __kernel_old_timeval __user *tv,
struct timezone __user *tz);
-asmlinkage long sys_settimeofday(struct timeval __user *tv,
+asmlinkage long sys_settimeofday(struct __kernel_old_timeval __user *tv,
struct timezone __user *tz);
asmlinkage long sys_adjtimex(struct __kernel_timex __user *txc_p);
asmlinkage long sys_adjtimex_time32(struct old_timex32 __user *txc_p);
diff --git a/kernel/time/time.c b/kernel/time/time.c
index bc114f0be8f1..6bfbe640fd3b 100644
--- a/kernel/time/time.c
+++ b/kernel/time/time.c
@@ -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 (tv->tv_usec > USEC_PER_SEC)
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)
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)))
--
2.20.0