[PATCH net 2/2] gve: Implement settime64 with -EOPNOTSUPP

[Joshua Washington]

From: Tim Hostetler <thostet@xxxxxxxxxx>

ptp_clock_settime() assumes every ptp_clock has implemented settime64().
Stub it with -EOPNOTSUPP to prevent a NULL dereference.

Fixes: acd16380523b ("gve: Add initial PTP device support")
Reported-by: syzbot+a546141ca6d53b90aba3@xxxxxxxxxxxxxxxxxxxxxxxxx
Closes: https://syzkaller.appspot.com/bug?extid=a546141ca6d53b90aba3
Signed-off-by: Tim Hostetler <thostet@xxxxxxxxxx>
Reviewed-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>
Signed-off-by: Joshua Washington <joshwash@xxxxxxxxxx>
---
 drivers/net/ethernet/google/gve/gve_ptp.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/net/ethernet/google/gve/gve_ptp.c b/drivers/net/ethernet/google/gve/gve_ptp.c
index 19ae699d4b18..a384a9ed4914 100644
--- a/drivers/net/ethernet/google/gve/gve_ptp.c
+++ b/drivers/net/ethernet/google/gve/gve_ptp.c
@@ -33,6 +33,12 @@ static int gve_ptp_gettimex64(struct ptp_clock_info *info,
 	return -EOPNOTSUPP;
 }
 
+static int gve_ptp_settime64(struct ptp_clock_info *info,
+			     const struct timespec64 *ts)
+{
+	return -EOPNOTSUPP;
+}
+
 static long gve_ptp_do_aux_work(struct ptp_clock_info *info)
 {
 	const struct gve_ptp *ptp = container_of(info, struct gve_ptp, info);
@@ -55,6 +61,7 @@ static const struct ptp_clock_info gve_ptp_caps = {
 	.owner          = THIS_MODULE,
 	.name		= "gve clock",
 	.gettimex64	= gve_ptp_gettimex64,
+	.settime64	= gve_ptp_settime64,
 	.do_aux_work	= gve_ptp_do_aux_work,
 };
 
-- 
2.51.2.997.g839fc31de9-goog