From 2ece068e1b1d6e76ecd07e04b027013e931287ff Mon Sep 17 00:00:00 2001 From: Muhammad Falak R Wani Date: Fri, 20 May 2016 17:51:02 +0530 Subject: [PATCH] ptp: use memdup_user(). Use memdup_user to duplicate a memory region from user-space to kernel-space, instead of open coding using kmalloc & copy_from_user. Signed-off-by: Muhammad Falak R Wani Acked-by: Richard Cochran Signed-off-by: David S. Miller --- drivers/ptp/ptp_chardev.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) diff --git a/drivers/ptp/ptp_chardev.c b/drivers/ptp/ptp_chardev.c index 579fd65299a0..0b1ac6be69ce 100644 --- a/drivers/ptp/ptp_chardev.c +++ b/drivers/ptp/ptp_chardev.c @@ -208,14 +208,9 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg) break; case PTP_SYS_OFFSET: - sysoff = kmalloc(sizeof(*sysoff), GFP_KERNEL); - if (!sysoff) { - err = -ENOMEM; - break; - } - if (copy_from_user(sysoff, (void __user *)arg, - sizeof(*sysoff))) { - err = -EFAULT; + sysoff = memdup_user((void __user *)arg, sizeof(*sysoff)); + if (IS_ERR(sysoff)) { + err = PTR_ERR(sysoff); break; } if (sysoff->n_samples > PTP_MAX_SAMPLES) { -- 2.30.2