From: Yangbo Lu <yangbo.lu@nxp.com>
Date: Mon, 5 Jul 2021 08:53:06 +0000 (+0800)
Subject: ptp: fix NULL pointer dereference in ptp_clock_register
X-Git-Tag: v5.15~716^2~46
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=55eac20617ca84129273ab248f4d7bfe456967de;p=platform%2Fkernel%2Flinux-starfive.git

ptp: fix NULL pointer dereference in ptp_clock_register

Fix NULL pointer dereference in ptp_clock_register. The argument
"parent" of ptp_clock_register may be NULL pointer.

Fixes: 73f37068d540 ("ptp: support ptp physical/virtual clocks conversion")
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c
index f012fa5..ce6d9fc 100644
--- a/drivers/ptp/ptp_clock.c
+++ b/drivers/ptp/ptp_clock.c
@@ -236,7 +236,7 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
 	}
 
 	/* PTP virtual clock is being registered under physical clock */
-	if (parent->class && parent->class->name &&
+	if (parent && parent->class && parent->class->name &&
 	    strcmp(parent->class->name, "ptp") == 0)
 		ptp->is_virtual_clock = true;