diff options
| author |   Sasha Levin <levinsasha928@gmail.com> | 2012-03-15 12:36:14 -0400 |
|---|---|---|
| committer |   Thomas Gleixner <tglx@linutronix.de> | 2012-03-15 21:41:34 +0100 |
| commit | a078c6d0e6288fad6d83fb6d5edd91ddb7b6ab33 (patch) | |
| tree | 473eb7484d966e65c51487c72d47502096ab7b99 /kernel/time | |
| parent | math: Introduce div64_long (diff) | |
| download | linux-dev-a078c6d0e6288fad6d83fb6d5edd91ddb7b6ab33.tar.xz linux-dev-a078c6d0e6288fad6d83fb6d5edd91ddb7b6ab33.zip | |
ntp: Fix integer overflow when setting time
'long secs' is passed as divisor to div_s64, which accepts a 32bit
divisor. On 64bit machines that value is trimmed back from 8 bytes
back to 4, causing a divide by zero when the number is bigger than
(1 << 32) - 1 and all 32 lower bits are 0.
Use div64_long() instead.
Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Cc: johnstul@us.ibm.com
Link: http://lkml.kernel.org/r/1331829374-31543-2-git-send-email-levinsasha928@gmail.com
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'kernel/time')
| -rw-r--r-- | kernel/time/ntp.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index 17fb1b9807d0..6e039b144daf 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -289,7 +289,7 @@ static inline s64 ntp_update_offset_fll(s64 offset64, long secs) time_status |= STA_MODE; - return div_s64(offset64 << (NTP_SCALE_SHIFT - SHIFT_FLL), secs); + return div64_long(offset64 << (NTP_SCALE_SHIFT - SHIFT_FLL), secs); } static void ntp_update_offset(long offset) |