Revert "time: Handle negative seconds correctly in timespec64_to_ns()"

This reverts commit 656f343d72 which is
commit 39ff83f2f6 upstream.

Arnd reports that this needs more review before being merged into all of
the trees.

Link: https://lore.kernel.org/r/CAK8P3a0z5jE=Z3Ps5bFTCFT7CHZR1JQ8VhdntDJAfsUxSPCcEw@mail.gmail.com
Reported-by: Arnd Bergmann <arnd@kernel.org>
Cc: Lukas Hannen <lukas.hannen@opensource.tttech-industrial.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Greg Kroah-Hartman 2021-09-16 11:12:30 +02:00
parent f49fd9882f
commit 1de280adb2

View file

@ -25,9 +25,7 @@ struct itimerspec64 {
#define TIME64_MIN (-TIME64_MAX - 1) #define TIME64_MIN (-TIME64_MAX - 1)
#define KTIME_MAX ((s64)~((u64)1 << 63)) #define KTIME_MAX ((s64)~((u64)1 << 63))
#define KTIME_MIN (-KTIME_MAX - 1)
#define KTIME_SEC_MAX (KTIME_MAX / NSEC_PER_SEC) #define KTIME_SEC_MAX (KTIME_MAX / NSEC_PER_SEC)
#define KTIME_SEC_MIN (KTIME_MIN / NSEC_PER_SEC)
/* /*
* Limits for settimeofday(): * Limits for settimeofday():
@ -126,13 +124,10 @@ static inline bool timespec64_valid_settod(const struct timespec64 *ts)
*/ */
static inline s64 timespec64_to_ns(const struct timespec64 *ts) static inline s64 timespec64_to_ns(const struct timespec64 *ts)
{ {
/* Prevent multiplication overflow / underflow */ /* Prevent multiplication overflow */
if (ts->tv_sec >= KTIME_SEC_MAX) if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX)
return KTIME_MAX; return KTIME_MAX;
if (ts->tv_sec <= KTIME_SEC_MIN)
return KTIME_MIN;
return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec; return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
} }