From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dong Zhu Subject: [PATCH] ptp: add range check on n_samples Date: Tue, 24 Sep 2013 15:05:57 +0800 Message-ID: <20130924070557.GA28795@zhudong.nay.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org To: Richard Cochran , David Miller Return-path: Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org >>From d4eb97e8d5def76d46167c91059147e2c7d33433 Mon Sep 17 00:00:00 2001 When using PTP_SYS_OFFSET ioctl to measure the time offset between the PHC and system clock, we need to specify the number of measurements, the valid value of n_samples is between 1 to 25. If n_samples <= 0 or > 25 it makes no sense, so this patch intends to add a range check. Signed-off-by: Dong Zhu --- drivers/ptp/ptp_chardev.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/ptp/ptp_chardev.c b/drivers/ptp/ptp_chardev.c index 34a0c60..4e85b23 100644 --- a/drivers/ptp/ptp_chardev.c +++ b/drivers/ptp/ptp_chardev.c @@ -104,7 +104,8 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg) err = -EFAULT; break; } - if (sysoff->n_samples > PTP_MAX_SAMPLES) { + if (sysoff->n_samples <= 0 || + sysoff->n_samples > PTP_MAX_SAMPLES) { err = -EINVAL; break; } -- 1.7.11.7 -- Best Regards, Dong Zhu